This invention relates to a portable electricity-generating apparatus comprising a reactor for producing hydrogen at low pressures, and a hydrogen fuel cell to generate electricity.

Background of the Invention As of 2017, up to one third of homes in the USA lose electrical power each year due to outages in electricity supplied by the electricity grid. In such outages, backup auxiliary sources of electricity are required to enable users to continue to use electrically powered items.

In recent years, fuel cells have become increasingly popular as a means of generating electricity in situations where there is no mains power available. Fuel cells which make use of alternative energy sources have a number of advantages over petrol- or diesel-fuelled internal combustion engines traditionally used in stand-alone power generators. The waste product of the operation of a fuel cell run on hydrogen is solely water, and no carbon dioxide or carbon monoxide is produced. Fuel cells are also more efficient than petrol- or diesel-fuelled internal combustion engines. A further advantage of a fuel cell compared to a conventional petroleum burning generator is that fuel cells can be miniaturised, thereby making them more portable.

Solar powered energy sources are a common type of auxiliary power supply used in domestic situations. However, these suffer from the disadvantage that they are less effective (or even fail to work at all) on cloudy days or at night.

An apparatus for generating electricity from hydrogen gas would be beneficial and would overcome problems associated with electricity generated from fossil fuels and solar energy. Although, at present, there are a number of apparatuses and systems for generating hydrogen gas, these are not suitable for domestic use. The generation of hydrogen by the reaction of aluminium with sodium hydroxide is described in US2009/0252671 (Fullerton). The hydrogen generating apparatuses of the type described above are relatively large scale fixed installations that are not readily suited for domestic use. There therefore remains the need for auxiliary, preferably portable, power supplies which make use of alternative energy sources (such as hydrogen). An advantage of a portable power supply is that this could be taken to remote locations where grid electricity is not available as a source of electricity. The Invention

The present invention provides an apparatus for generating electricity by converting hydrogen generated in situ within the apparatus into electricity. The apparatus is portable and is safe to use in domestic environments.

The apparatus comprises a housing inside which are mounted a reactor for producing hydrogen and a hydrogen fuel cell that consumes the hydrogen to produce electricity.

The apparatus comprises a chemical reactor in which a reaction takes place to generate hydrogen gas. The hydrogen gas can then exit the chemical reactor through a hydrogen gas outlet and can be delivered to other components of the apparatus for conversion into electricity. The chemical reactor comprises upper and lower body sections that are connected together to form a gas-tight seal but can be separated to allow the introduction of reactants into the chemical reactor. Typically, separation of the upper and lower sections constitutes the sole means by which reactants other than a liquid reactant or liquid reaction medium can be introduced into the chemical reactor. The upper and lower body sections are typically made from a suitable metal material, e.g. a corrosion-resistant metal material such as stainless steel. Alternatively, either or both of the upper and lower body sections can be made from a suitably tough, chemically resistant (to the reactants) and thermally resistant plastics material.

The upper and lower body sections are tightly connected together so that a substantially gas-tight seal is formed between them. A sealing element such as an elastomeric sealing gasket may be located between the upper and lower body sections to provide the substantially gas-tight seal. The upper and lower body sections can be secured to one another by means of a clamp or a threaded connection. Inside the chemical reactor is located a removable liner which is constructed so as to be able to contain reactants for the hydrogen-producing reaction. The reaction between the reactants takes place within the removable liner thereby avoiding or minimising the need for reactants to come into contact with the inner surfaces of the upper and lower body sections. The liner can be pre-filled with one or more reactants (typically solid reactants) and provided as a sealed liner with a removable lid that can be removed prior to placing the liner in the reactor. The liner may be formed (e.g. by moulding) from a suitable plastics material.

The reaction within the reactor is initiated by introducing a liquid reactant or liquid reaction medium (which in each case can be water) through one or more closable openings in a wall separating the upper body section from the lower body section. The liquid reactant or liquid reaction medium is therefore brought into contact with one or more reactants in the removable liner to produce hydrogen gas.

The reactor has a gas outlet through which hydrogen gas can exit the reaction chamber for onward flow to the fuel cell. Accordingly, in a first aspect of the invention (Embodiment 1.1 ) there is provided an apparatus for generating electricity, the apparatus comprising:

a housing and, mounted in the housing, a hydrogen fuel cell and a chemical reactor for producing hydrogen to supply the fuel cell to enable the fuel cell to generate electricity; and

a power output to which an electrical power-consuming device can be attached; wherein the chemical reactor comprises:

upper and lower body sections connected together so as to enclose a reaction chamber, the upper and lower body sections being separable to allow the introduction of one or more chemical reactants and reconnectable to form a gas-tight seal therebetween; the upper body section being capable of containing a liquid reactant or a liquid reaction medium;

a gas outlet through which hydrogen gas can exit the reactor;

a removable liner disposed inside the reaction chamber and being supported within the lower body section, the removable liner being constructed so as to be able to contain a liquid reaction medium and hold one or more chemical reactants therein; the removable liner being removable from the reaction chamber when the upper and lower body sections are separated; and

one or more closable openings being provided in a wall separating the upper and lower body sections (e.g. in a lower wall of the upper body section) for permitting communication between the upper and lower body sections, through which the liquid reactant or liquid reaction medium can pass from the upper body section into the removable liner in the lower body section such that a chemical reaction can take place between chemical reactants in the removable liner to produce hydrogen.

Further embodiments of the apparatus of the invention are set out in the following embodiments 1.2 to 1.6.

1.2 An apparatus according to Embodiment 1.1 wherein the upper and lower body sections are formed from a metal, such as stainless steel.

1 .3 An apparatus according to Embodiment 1.1 or Embodiment 1.2 wherein the reactor is substantially cylindrical in form. 1.4 An apparatus according to any one of Embodiments 1.1 to 1 .3 wherein the upper body section of the chemical reactor is in the form of a liquid reservoir.

1 .5 An apparatus according to any one of Embodiments .1 to .4 wherein the upper and lower body sections of the chemical reactor are removably connected together by means of a clamp or a threaded connection. 1.6 An apparatus according to any one of Embodiments 1.1 to 1 .5 wherein a sealing ring or gasket (e.g. an elastomeric seal) is provided between the upper and lower body sections of the chemical reactor to form a gas-tight seal when the upper and lower body sections are connected together.

The gas outlet may comprise an upwardly extending gas outlet conduit located in the lower body section of the reactor, the gas outlet conduit having one or more openings through which hydrogen gas produced in the reaction chamber can exit the chamber for onward flow to the hydrogen fuel cell. The upwardly extending gas outlet conduit can be, for example, a tube (a gas outlet tube) which is upstanding from and connected to a base or floor of the lower body section. Thus, gas produced in the reactor can exit the reaction chamber through one or more openings in the gas outlet conduit and then down and out through the base of the reactor.

The removable liner can be configured so as to surround the gas outlet conduit. Thus, the upwardly extending gas outlet conduit may be arranged centrally within the lower body section and the removable liner may be annular in form.

The gas outlet of the reactor may comprise a gas outlet valve which is actuable to permit hydrogen gas to exit the reaction chamber. Thus, when the gas outlet comprises a gas outlet conduit, the gas outlet conduit may be provided with a gas outlet valve.

The housing of the apparatus may comprise a docking base unit to which the chemical reactor can be removable connected.

The docking base unit may comprise a valve-engaging element which engages the gas outlet valve so as to open the valve to allow hydrogen to be drawn off.

The valve-engaging element may engage the gas outlet valve of the chemical reactor when the chemical reactor is attached to the docking body so as to open the valved outlet to allow hydrogen to be drawn off.

Alternatively, the valve engaging element may be connected via a length of tubing or hose to the docking body.

The valve-engaging element may be upwardly protruding in relation to the docking base unit. The docking base unit may also have a recess into which the chemical reactor may be placed, in a plug and socket type arrangement.

Accordingly, in further embodiments (Embodiments 1.7 to 1.18), the invention provides:

1.7 An apparatus according to any one of Embodiments 1.1 to 1.6 wherein the gas outlet comprises an upwardly extending gas outlet conduit located within the lower body section, the upwardly extending gas conduit serving to connect the reaction chamber to the gas outlet to enable hydrogen gas produced in the reaction chamber to exit the reaction chamber for onward flow to the fuel cell. 1.8 An apparatus according to Embodiment 1.7 wherein the gas outlet conduit is upstanding from and connected to a base or floor of the lower body section.

1.9 An apparatus according to Embodiment 1.7 or Embodiment 1.8 wherein the gas outlet conduit takes the form of a gas outlet tube. 1.10 An apparatus according to Embodiment 1.9 wherein the gas outlet tube is disposed centrally within the reaction chamber.

1.1 1 An apparatus according to any one of Embodiments 1.7 to 1.10 wherein the removable liner is configured so as to surround the gas outlet conduit.

1.12 An apparatus according to Embodiment 1.11 wherein the gas outlet conduit is arranged centrally within the lower body section and the removable liner is annular in form.

1.13 An apparatus according to any one of Embodiments 1.1 to 1.12 wherein the apparatus comprises a docking base unit to which the reactor can be removably connected.

1.14 An apparatus according to any one of Embodiments 1.1 to 1.13 wherein the gas outlet comprises a gas outlet valve which is actuable to permit hydrogen gas to exit the reaction chamber.

1. 5 An apparatus according to Embodiment 1 ,14 wherein the docking base unit comprises a valve-engaging element which engages the gas outlet valve to actuate the valve.

1.16 An apparatus according to Embodiment 1.15 wherein the valve-engaging element engages the gas outlet valve when the reactor is attached to the docking base unit so as to open the valve.

1.17 An apparatus according to Embodiment 1.15 or Embodiment 1.16 wherein the valve-engaging element is upwardly protruding in relation to the docking base unit.

1.18 An apparatus according to any one of Embodiments 1.13 to 1.17 wherein the docking base unit has a recess into which the reactor may be placed (for example, in a plug and socket type arrangement). When the gas outlet comprises an upwardly extending gas outlet conduit located within the lower body section, the gas outlet conduit may be provided with a gas outlet valve. The gas outlet valve reversibly blocks one or more openings in the gas outlet conduit that allow hydrogen gas to exit the reaction chamber. The gas outlet valve may comprise a valve stem and a valve member (which may also be referred to herein as an obturating member) and the gas outlet conduit may be configured to provide a passage therethrough in which the valve stem is located, the valve stem being reciprocally movable in the passage between a closed position in which the valve member blocks the one or more openings in the gas outlet conduit so that hydrogen cannot pass out through the passage, and an open position in which hydrogen can pass out through the passage.

A spring or other resilient restoring means is typically provided for biasing the valve member towards the closed position. The spring may be located in the passage through the gas outlet conduit.

The valve member (which can for example be substantially disc-shaped) may be mounted at an upper end of the valve stem and may be configured to form a seal against an upper surface of the gas outlet conduit. Thus, the upper end of the gas outlet conduit may be configured to provide a valve seat for the valve member. The valve seat may comprise a recess in the upper end of the gas outlet conduit, in which recess the valve member may sit when the valve is closed. Either or both of the valve member and the upper surface or seat of the gas outlet conduit may be provided with an elastomeric sealing member for forming a seal therebetween. In one embodiment, the elastomeric sealing member is mounted on the upper surface of the gas outlet conduit. In another embodiment, the elastomeric sealing member is mounted on the valve member. The elastomeric sealing members are advantageously formed from a fluoroelastomer.

The elastomeric sealing members can take the form of sealing pads or washers but more preferably take the form of an O-ring which may be seated in an appropriately sized annular groove.

The valve-engaging element of the docking body may be arranged to open the gas outlet valve by urging the valve stem upwards so as to move the valve member from the closed position to the open position. For example, where the gas outlet conduit has an opening in an upper end thereof which is closed by the valve member, the gas outlet valve may be opened by virtue of the upward movement of the valve stem lifting the valve member away from the opening (e.g. out of the valve seat). Alternatively, when the gas outlet conduit has lateral openings, the valve member may be arranged to move between (i) a closed position in which either the lateral openings are blocked or the gas outlet conduit is blocked downstream of the lateral openings, and (ii) an open position in which the lateral openings are not blocked and the gas outlet conduit is not blocked downstream of the lateral openings. An advantage of the valve being located on or in the upstanding gas outlet conduit is that the reactants will tend to fall to the floor of the chemical reactor surrounding the gas outlet conduit rather than accreting on the valve.

Accordingly, in further embodiments (Embodiments 1.19 to 1.31 ), the invention provides:

1.19 An apparatus according to any one of Embodiments 1.1 to 1.18 wherein the gas outlet comprises an upwardly extending gas outlet conduit located within the lower body section, and the gas outlet conduit is provided with a gas outlet valve which reversibly blocks one or more openings in the gas outlet conduit that allow hydrogen gas to exit the reaction chamber.

1 .20 An apparatus according to Embodiment 1. 9 wherein the gas outlet valve comprises a valve member which is resiliently biased towards a closed position.

1.21 An apparatus according to Embodiment 1.19 or Embodiment 1.20 wherein the gas outlet valve comprises a valve stem and a valve member and the gas outlet conduit is configured to provide a passage therethrough in which the valve stem is located, the valve stem being reciprocally movable in the passage between a closed position in which the valve member blocks the one or more openings in the gas outlet conduit so that hydrogen cannot pass out through the passage, and an open position in which hydrogen can pass out through the passage.

1.22 An apparatus according to Embodiment 1.21 wherein the apparatus comprises a docking base unit to which the reactor is removably connected and wherein the docking base unit has a valve-engaging element which is arranged to open the gas outlet valve by urging the valve stem upwards so as to move the valve member from the closed position to the open position when the reactor is placed on the docking base unit.

1 .23 An apparatus according to Embodiment 1.21 or Embodiment 1.22 wherein the gas outlet conduit has an opening in an upper end thereof which is closed by the valve member, and wherein the gas outlet valve is opened by virtue of upward movement of the valve stem lifting the valve member away from the opening.

1 .24 An apparatus according to Embodiment 1.20 wherein the gas outlet conduit has lateral openings, and the valve member is arranged to move between a closed position in which the lateral openings are blocked, and an open position in which the lateral openings are not blocked.

1.25 An apparatus according to any one of Embodiments 1 .20 to 1.24 comprising a spring or other resilient restoring means for biasing the valve member towards the closed position. 1 .26 An apparatus according to Embodiment 1.25 wherein the spring or other resilient restoring means is located in the passage through the gas outlet conduit.

1 .27 An apparatus according to any one of Embodiments 1.21 to 1.26 wherein the valve member (which can for example be substantially disc-shaped) is mounted at an upper end of the valve stem and is configured to form a seal against an upper surface of the gas outlet conduit. .28 An apparatus according to Embodiment 1.27 wherein the upper surface of the gas outlet conduit is configured to provide a valve seat for the valve member (for example wherein the valve seat comprises a recess in the upper end of the gas outlet conduit, in which recess the valve member may sit when the valve is closed). 1 .29 An apparatus according to Embodiment 1.27 or Embodiment 1.28 wherein either or both of the valve member and the upper surface of the gas outlet conduit are provided with an elastomeric sealing member for forming a seal therebetween. 1.30 An apparatus according to Embodiment 1.29 wherein the elastomeric sealing member is mounted on the valve member.

1 .31 An apparatus according to Embodiment 1.29 or Embodiment 1.30 wherein the elastomeric sealing member takes the form of a sealing pad or washer. The apparatus generates hydrogen through mixing one or more reactants, typically solid reactants, with a liquid reactant or in a liquid reaction medium. The liquid reactant or reaction medium may be stored within the apparatus in the upper body section (the interior of which may be referred to for convenience as a "liquid storage area" or "reservoir"). In use, the liquid passes from the upper body section through the one or more closable openings into the lower body section (more specifically into the removable liner) where a reaction between the reactants takes place in the removable liner to generate hydrogen gas.

Thus, the liquid entering the lower body section through the closable opening(s) may be a liquid reactant which reacts with reactants (e.g. solid reactants) in the removable liner, or it may be a liquid reaction medium which solubilizes one or more reactants in the removable liner so that reaction can take place between solid reactants that would not react with one another in the dry state. The liquid may serve as both a reactant and a reaction medium.

The liquid preferably comprises or consists of water which reacts with one or more reactants in the removable liner as well as functioning as a reaction medium. Examples of solid reactants that may be present in the removable liner include aluminium and alkali metal hydroxides such as sodium hydroxide.

The reactor is provided with one or more closable openings in a wall separating the upper and lower body sections which allow movement of liquid from the reservoir in the upper body section to the lower body section under the influence of gravity. Once the liquid has been released and moved into the lower body section, it may react with the reactants (e.g. solid reactants) in the lower body section to form hydrogen gas. The openings are typically closable by a moveable physical barrier, which prevents unwanted movement of liquid from the upper body section into the lower body section. The one or more closable openings that allow water to enter the reaction chamber in the lower body section may be referred to herein as "first openings" or "first closable openings". Thus, the upper body section of the reactor is hollow and is capable of containing a liquid reactant or liquid reaction medium. The upper body section may, for example, be substantially cylindrical in form with a lower wall in which are located the closable openings. A lower end of the substantially cylindrical upper body section may have an external thread to enable it to be connected to the lower reactor body section, as described above.

Some or all of the first closable openings in the wall separating the upper and lower body sections may be provided with a flow regulator for restricting the flow of liquid through the opening(s) to provide a controlled release of the liquid reactant from the liquid storage container to the reaction area. Alternatively, or additionally, the flow of liquid may be controlled by the diameter of the opening. For example, one or more of the first openings may have a diameter of 1 mm or less, for example 0.8 mm or less, 0.7 mm or less or 0.5 mm or less.

When the closable openings are provided in a lower wall of the upper body section, the lower wall may also be provided with one or more additional openings that can be used to fill the liquid storage area in the upper body section with the liquid reactant when the upper and lower body sections are disassembled (e.g. unscrewed). Such additional openings, which may be referred to herein for convenience as "second" openings, may optionally be fitted with a valve to allow liquid to enter the reservoir in the upper body section but prevent liquid from leaving the upper body section. The second closable openings are typically larger than the first closable openings.

The apparatus may also be provided with a further additional opening connected to an air- bleed tube which extends into the upper body section to an area above a maximum fill line in the upper body section when full. This further additional opening, which may be referred to herein for convenience as a "third" or "air-bleed" opening, provides an air passage between the lower body section and the upper body section to equilibrate the pressure between the two body sections and thereby allow fluid to continuously pass therebetween.

The first closable openings are located between the upper and lower body sections and are typically located in a lower wall of the upper body section of the chemical reactor.

Alternatively, the first closable openings may be located on an upper surface or upper face of the lower body section of the chemical reactor. The first openings are closable by one or more closure devices. The closure device(s) may comprise one or more moveable, for example rotatable, valve plates which can be moved (e.g. rotated) to cover or uncover the openings. The moveable (e.g. rotatable) valve plates may bear one or more sealing elements to provide a water-tight seal when the plate covers the opening(s).

The closure device may be mounted above or below the wall separating the upper and lower body sections. Thus, for example, the closure device may be mounted on the top side or underside of the lower wall of the upper body section. However, when a third opening is present in the wall, and the third opening is connected to a tube extending up beyond the maximum fill line in the upper body section, the closure device is mounted on the underside of the lower wall of the upper body section.

A single closure device may be provided which is able to close each of the first, second and (where present) third openings, or each opening (or group of openings) may be provided with its own closure device. When the first, second and/or third closable openings are all present in a lower wall of the upper body section, the moveable (e.g. rotatable) valve plate may be configured so as to be moveable to cover or uncover each of the openings in a desired sequence.

For example, the valve plate can be movable between a closed first position whereby at least the first and second openings are covered (and hence closed), a second position where the first and (where present) third opening(s) are uncovered (and hence opened), and a third position wherein the second and optionally the third openings (when present) are uncovered (and hence opened).

In the first position, the valve plate may be positioned such that all openings in the upper body section are covered by the closure device to prevent liquid from entering or leaving the upper body section.

In the second position, the closure device does not cover the first openings and hence liquid (e.g. water) can pass through the openings and into the liner in the lower body section. In this position, the third opening (when present) may be uncovered so as to act as an air bleed allowing air to pass between the upper and lower body sections to equalise the pressures in the two sections and facilitate liquid flow in to the lower body section. In the third configuration, the closure device may be positioned such that none of the first, second or (when present) third openings are covered by the closure device. Alternatively, in the third configuration, the closure device may be positioned such that at least one opening (e.g. the second opening) is covered through which liquid can be filled into the upper body section when the upper and lower body sections have been separated.

The movable closure device may comprise an actuating member that allows the closure device to be actuated from the exterior of the apparatus without impairing the gas-tightness of the reaction chamber. For example, the actuating member may comprise a shaft which extends from the interior or the reactor through a gas-seal to the exterior and which can be moved (e.g. rotated) thereby to move (e.g. rotate) the valve plate(s). The shaft may be fitted with a handle to aid movement (e.g. rotation) of the shaft.

Thus, by rotation of the plate using the handle and shaft, the closure device is rotatable, between first, second and optionally third positions.

Accordingly, in further embodiments (1.32 to 1.52) there are provided: 1 .32 An apparatus according to any one of Embodiments 1.1 to 1.31 wherein a liquid comprising or consisting of water serves as the liquid reactant and/or liquid reaction medium.

1.33 An apparatus according to any one of Embodiments .1 to 1.32 wherein the upper body section is hollow and serves as a reservoir for the liquid. 1 .34 An apparatus according to any one of Embodiments 1.1 to 1.33 wherein the upper body section is substantially cylindrical in form; for example, wherein the upper body section comprises upper and lower circular walls linked by a cylindrical side wall.

1.35 An apparatus according to Embodiment 1.34 wherein a lower end of the upper body section has an external thread to enable it to be connected to the lower reactor body section.

1.36 An apparatus according to any one of Embodiments 1.1 to 1 .35 comprising one or more closable first openings in a wall separating the upper and lower body sections, which closable first openings when open allow liquid to flow from the upper body section to the lower body section.

1.37 An apparatus according to Embodiment 1.36 wherein each of the one or more closable first openings have a diameter of 1 mm or less, for example 0.8 mm or less, 0.7 mm or less or 0.5 mm or less.

1.38 An apparatus according to Embodiment 1.36 or Embodiment 1.37 wherein the one or more first openings are located in a lower wall of the upper body section.

1 .39 An apparatus according to any one of Embodiments 1.36 to 1.38 wherein the lower wall of the upper body section is provided with one or more second closable openings that can be used to fill the upper body section with liquid when the upper and lower body sections are disassembled.

1 .40 An apparatus according to Embodiment .39 wherein the second closable openings are larger than the first closable openings.

1 .41 An apparatus according to any one of Embodiments 1.1 to 1.40 wherein one or more movable closure devices are provided for preventing or allowing passage of liquid through the first and (where present) second closable openings.

1.42 An apparatus according to any one of Embodiments 1.36 to 1.41 wherein the lower wall of the upper body section is provided with one or more third closable openings, each third opening being connected to a pressure equalisation tube which extends into the upper body section to an area above a fluid line in the upper body section when full.

1.43 An apparatus according to Embodiment 1.42 wherein one or more movable closure members is provided for closing the third closable openings.

1.44 An apparatus according to Embodiment 1.43 wherein the movable closure member is mounted on an underside of the lower wall of the upper body section. 1.45 An apparatus according to any one of Embodiments 1.41 to 1.44 wherein a single movable closure device is provided which can open or close each of the first, second and (where present) third closable openings in a desired sequence. 1.46 An apparatus according to Embodiment 1.45 wherein the single movable closure device is mounted on an underside of the lower wall of the upper body section.

1.47 An apparatus according to Embodiment 1.45 or Embodiment 1.46 wherein the single movable closure device is movable (e.g. rotatable) between a closed first position whereby at least the first and second openings are covered (and hence closed), a second position where the first and (where present) third opening(s) are uncovered (and hence opened), and a third position wherein the second and optionally the third openings (when present) are uncovered (and hence opened).

1.48 An apparatus according to Embodiment 1.46 or Embodiment 1.47 wherein the single movable closure device comprises a movable valve plate.

1.49 An apparatus according to Embodiment 1.48 wherein the movable valve plate is rotatable between the first, second and third positions.

1.50 An apparatus according to any one of Embodiments 1.41 to 1.49 wherein the movable closure device is provided with one or more seals (e.g. elastomeric sealing elements) for providing a liquid-tight seal at the one or more first and second and optionally the third (when present) openings.

1 .51 An apparatus according to any one of Embodiments 1.41 to 1.50 wherein the movable closure device comprises an actuating member that allows the closure device to be actuated from the exterior of the apparatus without impairing the gas-tightness of the reaction chamber.

1.52 An apparatus according to Embodiment 1.51 wherein the actuating member is a rotatable shaft which extends through a gas-tight seal to the reactor exterior

As described above, the apparatus comprises a removable liner which contains one or more reactants which can react to generate hydrogen gas. The removable liner, which is located inside the reaction chamber and is typically supported within the lower body section, is removable from the reaction chamber when the upper and lower body sections are separated. The removable liner is typically shaped to conform to the inner contours of a lower part of the reaction chamber. Thus, for example, when the reaction chamber is cylindrical and the gas conduit is a tube which is upstanding from a base of the lower body section, the removable liner may be configured so as to conform to the shape of the gas conduit. Thus, for example, the removable liner may surround the gas conduit. More particularly, the removable liner can be annular in shape. The annular removable liner may have a ring- shaped base portion and (typically concentric) cylindrical inner and outer walls, the space between the inner and outer walls serving to hold the reactants during reaction to form hydrogen. The inner wall typically surrounds a central passage within which the upstanding gas conduit is located.

The removable liner may have an interior (e.g. the space between the inner and outer walls when present) which is partitioned into a plurality of individual compartments, each of which can contain a dose of reactants that can react together with or in the presence of the liquid reactant or liquid reaction medium to form hydrogen. By providing a plurality of separate compartments each containing a set of reactants, the generation of hydrogen can be controlled more closely. For example, the compartments can be configured so that the liquid from the first opening(s) falls into one or a selected number of (but not all)

compartments so that reaction is initiated in the one compartment or selected number of compartments in question, and then flows to other compartments thereby bringing about reaction in those compartments. The compartments can be configured so that liquid from one compartment will only flow to another (e.g. adjacent) compartment when liquid in the one compartment has reached a particular level. Thus, for example, partition walls between the compartments can be configured so that when the liquid in one compartment has reached a particular level, it will overflow into only a single or selected small number of (e.g. one, two or three) adjacent compartments, and preferably only a single adjacent compartment. In this way, the extent of reaction in the reaction chamber can be controlled by controlling the rate of flow of water into the reaction chamber.

When the removable liner has concentric inner and outer walls, the space between the concentric inner and outer walls may be divided into a plurality of compartments by one or more partition walls extending in a radially outward direction from the inner circular wall.

One or more further concentric intermediate cylindrical walls may also be provided between the inner and outer walls thereby increasing the number of compartments. When there are two or more radially extending partition walls, one of the radially extending partition walls may have a height greater than the other radially extending partition walls and the liquid inlet may be positioned so that liquid is initially deposited in a compartment bounded on one side by the higher radially extending partition wall. As liquid is introduced into the compartment, it will eventually overflow in a direction away from the higher radially extending partition wall. Depending on which side of the higher radially extending partition wall the liquid is introduced into a compartment, the liquid flow around the liner may be either clockwise or anticlockwise.

Where there are one or more further concentric intermediate cylindrical walls between the inner and outer walls, a more convoluted flow path may be provided by configuring the partition walls between adjacent compartments so that a first compartment (where the liquid is initially received) has a single partition wall of reduced height and all except one of the remaining compartments have two partition walls of reduced height so that liquid can pass from the first compartment sequentially through the other compartments to a final compartment in the flow path, which has only a single partition wall of reduced height.

Alternatively (or additionally), the partition walls separating the compartments can be provided with openings that are arranged to direct the flow of liquid around the liner in a predetermined manner. For example, a first compartment (where the liquid is initially received) and the final compartment in the flow path may each have a single opening and the remaining compartments may have two or more (typically only two) openings through which liquid may pass. The term "opening" in the context of the openings in the partition walls can mean either a hole or a notch or cut away region in a wall.

When the liner has one or more further concentric intermediate cylindrical walls between the inner and outer walls, each cylindrical intermediate wall may have a height of less than the inner and outer walls (for example, a height of less than half of the height of the outer wall.)

It will be appreciated from the foregoing that by virtue of the radially extending partition wall(s) and, when present, the concentric intermediate wall(s), the interior of the removable liner is configured to provide a discrete number of compartments into which measured weights or volumes of reactant can be added. Each compartment may, for example, contain the same weight of reactant. Alternatively, but less usually, different amounts of reactants can be provided in each compartment.

The liquid is introduced into the removable liner through the open top of the liner.

The removable liner is typically integrally formed (e.g. by a moulding technique such as injection moulding) from a mouldable plastics material, and more preferably a

biodegradable plastics material.

The plastics material is chosen so that it is impervious to water and any other liquids that may be used as a reactant or reaction medium, and is resistant to the both the reactants and the reaction products. Examples of suitable plastics materials include polyamides such as nylon, biodegradable polymers such as polylactic acid/polylactide and mixtures thereof.

The removable liner and/or each compartment thereof, contains one or more reactants that react with or in the presence of the liquid to produce hydrogen. There may, for example, be only a single reactant which reacts with water (when water is the liquid introduced through the liquid inlet) or there may be two or more reactants that react with or in the presence of the liquid (e.g. water) to give hydrogen.

The reactants may, for example, comprise aluminium and an alkali metal hydroxide such as sodium hydroxide. Both the alkali metal hydroxide and the aluminium will typically be in particulate (e.g. powder) form. As an alternative, a metal borohydride such as sodium borohydride may be used as the reactant. Sodium borohydride reacts with water to produced hydrogen.

The removable liner may be provided with an alignment guide which engages a complementary guide element in the interior of the reactor so that the removable liner can only be placed in the reactor in a predetermined orientation. The alignment guide can be, for example, selected from one or more of grooves, recesses, ribs, ridges, protrusions or groups of protrusion that engage one or more complementary grooves, recesses, ribs, ridges, protrusions or groups of protrusions in or from an internal wall of the reactor. More particularly, the alignment guide can be, for example, a groove extending down an outer face of the removable liner, wherein the groove engages a protrusion extending inwardly from the internal wall of the reactor (for example an internal wall of the lower body section). Thus, in further embodiments (Embodiments 1 .53 to 1 .77), the invention provides:

1 .53 An apparatus according to any one of Embodiments 1 .1 to 1 .52 wherein the removable liner is shaped to conform to the inner contours of a lower part of the reaction chamber. 1.54 An apparatus according to any one of Embodiments 1 .1 to 1 .53 wherein the reaction chamber is cylindrical, the gas conduit is a tube which is upstanding from a base of the lower body section, and the removable liner is configured so as to conform to the shape of (e.g. surround) the gas conduit.

1 .55 An apparatus according to Embodiment 1 .54 wherein the removable liner is annular in shape.

1 .56 An apparatus according to Embodiment 1 .55 wherein the annular removable liner has a ring-shaped base portion and cylindrical (typically concentric) inner and outer walls, the space between the inner and outer walls serving to hold the reactants during reaction to form hydrogen. 1.57 An apparatus according to Embodiment 1 .56 wherein the inner wall surrounds a central passage within which the upstanding gas conduit is located.

1 .58 An apparatus according to Embodiment 1 .56 or Embodiment 1.57 wherein one or more further concentric intermediate cylindrical walls are provided between the inner and outer walls. 1 .59 An apparatus according to any one of Embodiments 1.1 to 1 .58 wherein the removable liner has an interior (e.g. the space between the inner and outer walls and any intermediate cylindrical walls when present) which is partitioned into a plurality of individual compartments, each of which can contain a dose of reactants that can react together with or in the presence of the liquid reactant or liquid reaction medium to form hydrogen. 1 .60 An apparatus according to Embodiment 1 .59 wherein the compartments are configured so that liquid from the upper body section falls into one or a selected number, but not all, of the compartments so that reaction is initiated in the one compartment or selected number of compartments, and then flows to other compartments thereby bringing about reaction in the said other compartments.

1.61 An apparatus according to Embodiment 1.60 wherein the compartments are configured so that liquid from one compartment will only flow to another (e.g. adjacent) compartment when liquid in the one compartment has reached a particular level.

1.62 An apparatus according to Embodiment 1.61 wherein partition walls between the compartments are configured so that when the liquid in one compartment has reached a particular level, it will overflow into only a single or selected small number of (e.g. one, two or three) adjacent compartments, and preferably only a single adjacent compartment. 1.63 An apparatus according to any one of Embodiments 1.1 to 1.62 wherein the removable liner has concentric inner and outer walls, and the space between the concentric inner and outer walls is divided into a plurality of compartments by one or more partition walls extending in a radially outward direction from the inner wall.

1 .64 An apparatus according to Embodiment 1 .63 wherein one of the radially extending partition walls has a height greater than the other radially extending partition walls and the liquid inlet is positioned so that liquid is initially deposited in a compartment bounded on one side by the higher radially extending partition wall.

1.65 An apparatus according to Embodiment .64 wherein the partition walls between adjacent compartments are configured so that a first compartment (where the liquid is initially received) has a single partition wall of reduced height and all except one of the remaining compartments have two partition walls of reduced height so that liquid can pass from the first compartment sequentially through the other compartments along a flow path to a final compartment in the flow path, which has only a single partition wall of reduced height. 1 .66 An apparatus according to any one of Embodiments .59 to 1.65 wherein partition walls separating the compartments are provided with openings that are arranged to direct the flow of liquid around the liner along a predetermined flow path. 1.67 An apparatus according to Embodiment 1.66 wherein a first compartment (where the liquid is initially received) and a final compartment in the flow path each have a single opening and the remaining compartments have two or more.

1.68 An apparatus according to Embodiment 1.67 wherein the said remaining compartments have only two openings through which liquid may pass.

1.69 An apparatus according to Embodiment 1.58 and any Embodiment dependent thereon wherein each intermediate wall has a height of less than the inner and outer walls.

1.70 An apparatus according to Embodiment 1.69 wherein each intermediate wall has a height of less than half of the height of the outer wall. 1.71 An apparatus according to any one of Embodiments 1.1 to 1.70 wherein the removable liner is integrally formed from a mouldable plastics material.

1.72 An apparatus according to Embodiment 1 .71 wherein the plastics material is a biodegradable plastics material.

1.73 An apparatus according to Embodiment 1.72 wherein the plastics material is selected from polyamides such as nylon, biodegradable polymers such as polylactic acid/polylactide and mixtures thereof.

1.74 An apparatus according to any one of Embodiments 1.1 to 1.73 wherein the reactants comprise aluminium and an alkali metal hydroxide such as sodium hydroxide.

1.75 An apparatus according to any one of Embodiments 1.1 to 1.74 wherein the removable liner is provided with an alignment guide which engages a complementary guide element in the interior of the reactor so that the removable liner can only be placed in the reactor in a predetermined orientation.

1.76 An apparatus according to Embodiment 1.75 wherein the alignment guide comprises one or more elements selected from grooves, recesses, ribs, ridges, protrusions or mixtures thereof that engage one or more complementary elements selected from grooves, recesses, ribs, ridges, protrusions or mixtures thereof in or from an internal wall of the reactor. 1.77 An apparatus according to Embodiment 1 .76 wherein the alignment guide comprises a groove extending down an outer face of the removable liner, wherein the groove engages a protrusion extending inwardly from the internal wall of the reactor (for example an internal wall of the lower body section). Hydrogen generated in the reaction chamber exits the reaction chamber through the gas outlet whence it typically passes through tubing to a water-removing device (for example a water trap and/or desiccator) and then a pressure-reducing device to the fuel cell. The pressure reducing device reduces the gas pressure to a pressure suitable for the particular type of fuel cell. The fuel cell is preferably a proton exchange membrane (PEM) fuel cell. The pressure-reducing device can be selected so as to limit the pressure of hydrogen entering the fuel cell to a pressure of no more than 1 bar, e.g. no more than 0.7 bar, or no more than 0.5 bar. When the fuel cell is a PEM cell, the pressure-reducing device may be one which limits the pressure to no more than 0.5 bar.

Accordingly, in further embodiments of the invention (Embodiments 1.78 to 1 .82) there are also provided:

1.78 An apparatus according to any one of Embodiments 1.1 to 1 .11 comprising a water- removing device located downstream of the gas outlet of the reactor and upstream of the hydrogen fuel cell.

1.79 An apparatus according to Embodiment 1.78 wherein the water removing device comprises a water trap.

1 .80 An apparatus according to any one of Embodiments 1.1 to 1.79 comprising a pressure reducing device located upstream of the fuel cell (e.g. between the water- removing device (when present) and the fuel cell) for limiting the pressure of hydrogen gas entering the fuel cell. 1 .81 An apparatus according to Embodiment 1.80 wherein the pressure reducing device limits the pressure of hydrogen entering the fuel cell to a pressure of no more than 1 bar, more typically no more than 0.7 bar, and preferably no more than 0.5 bar.

1.82 An apparatus according to any one of Embodiments 1.1 to .81 wherein the hydrogen fuel cell is a proton-exchange membrane (PEM) fuel cell. PEM fuel cells comprise an anode and a cathode, between which are sandwiched a polymeric electrolyte membrane which is capable of conducting hydrogen ions between the anode and cathode. Hydrogen gas is channelled to the anode where it is catalytically split to form hydrogen atoms which then give up an electron to form hydrogen ions. The electrons flow along an electrical connection to the cathode thereby giving rise to an electric current (which provides the power output for the fuel cell) while the hydrogen ions migrate through the membrane to the cathode. At the cathode, oxygen gas is catalytically split to form oxygen atoms which each acquire two electrons (via the electrical connection to the anode) and then combine with two protons to form water as the electrochemical reaction product. The anode and cathode may each be formed from, for example, a carbon support, catalyst (e.g. platinum) particles, an ionomer (e.g. Nafion ionomer) and a binder (e.g. PTFE - Teflon®). The catalyst facilitates the electrochemical reactions at the anode and cathode by splitting the hydrogen (H ₂ ) and oxygen (0 ₂ ) molecules. The ionomer provides paths for hydrogen ion conduction. The polymeric electrolyte membrane (also known as a proton- exchange membrane or PEM) is a semipermeable membrane which is typically formed from ionomers and is intended to conduct protons while also acting as an electronic insulator and a barrier to oxygen and hydrogen gas. Thus, the PEM serves to separate the reactants hydrogen and oxygen and facilitate the transport of protons while blocking a direct electronic pathway through the membrane. A feature of some PEM fuel cells is that the PEM cell purges (expels hydrogen) at regular intervals (e.g. every 7 seconds). At each point where purging takes place, the generation of electricity is interrupted for a period which is typically less than a second (for example up to about 150 milliseconds). As a consequence, production of electricity is not continuous. This gives rise to a problem in that, without a continuous supply of electricity, at least some of the electronic components of the apparatus will cease to work thereby resulting in the apparatus shutting down. In addition, the electrical output of the apparatus will also be discontinuous.

The present invention overcomes this problem by using one or more (typically a plurality) of charge storage devices which rapidly release charge at each interruption in the power generation and thereby smooth or reduce the magnitude of fluctuations in the electrical output of the apparatus. The charge storage devices can be rechargeable batteries but, more usually, are capacitors and in particular are supercapacitors (also known as double layer capacitors or ultracapacitors). Supercapacitors have very rapid rates of charge and discharge. Supercapacitors are able to store much greater amounts of charge than conventional capacitors. For example, individual capacitors for use in the apparatus of the invention may each have a capacitance of 250pF or greater, more usually 300pF or greater, for example 350pF or greater. Each individual supercapacitor may operate at a voltage of, for example 2-5 volts. A bank of supercapacitors (for example 8-12

supercapacitors) may therefore be used to increase the total voltage to a level

corresponding to that of the output of the PEM cell, for example to 30 volts. Examples of commercially available supercapacitors that may be used in the apparatus of the present invention are the supercapacitors produced by Maxwell Technologies of San Diego, USA and Eaton Corporation.

Accordingly, in further embodiments (Embodiments 1.83 to 1.90), the invention provides:

1.83 An apparatus according to Embodiment 1.82 further comprising one or more charge storage devices which release charge when there is an interruption of power output from the PEM cell.

1 .84 An apparatus according to Embodiment 1.83 wherein the charge storage device is connected in parallel to the fuel cell.

1.85 An apparatus according to Embodiment 1.83 or 1.84 wherein the charge storage device is a rechargeable battery. 1 .86 An apparatus according to Embodiment 1.83 or 1.84 wherein the charge storage device is a capacitor.

1 .87 An apparatus according to any one of Embodiments 1.83 to 1.86 comprising a plurality of charge storage devices. .88 An apparatus according to Embodiment 1.87 wherein the plurality of charge storage devices comprises a plurality of supercapacitors.

1 .89 An apparatus according to Embodiment 1.86 or Embodiment 1.87 wherein the plurality of charge storage devices comprises a plurality of capacitors (e.g. supercapacitors) and the total voltage produced by the plurality of capacitors (e.g. supercapacitors) corresponds (or corresponds substantially) to the voltage output of the PEM cell.

1.90 An apparatus according to Embodiment 1.89 wherein the plurality of charge storage devices comprises a plurality of capacitors (e.g. supercapacitors) and the total voltage output of the plurality of capacitors (e.g. supercapacitors) is approximately 30 volts.

The apparatus of the invention is provided with one or more power outlets. The power outlets may take the form of one or more plug sockets. Alternatively, or additionally, the power outlets may take the form of an induction charger outlet.

The power output from the apparatus may be either DC or AC or a combination of DC and AC. Thus the apparatus may be provided with DC and/or AC plug sockets and preferably both DC and AC sockets. One or more DC sockets may take the form of USB sockets.

As the power generated by the PEM cell is DC power, the apparatus may comprise an AC/DC power inverter. The output of the PEM cell may be below the levels (e.g. 1 15V in the USA or 240V in the UK) provided by mains electricity and required to run most electrical devices. Therefore, the apparatus may comprise a voltage-boosting device to increase the voltage available from the power outlets to the level of a mains supply. The voltage boosting device may, for example, comprise one or more capacitors.

Accordingly, in further embodiments (Embodiments 1.91 to 1.97) there is provided:

1.91 An apparatus according to any one of Embodiments 1.1 to 1.90 wherein the apparatus comprises a DC/AC power inverter.

1.92 An apparatus according to Embodiment 1.91 wherein the power outlets comprise one or more AC power outlets providing power at a mains level voltage (for example, 115V or 240V).

1.93 An apparatus according to any one of Embodiments 1.1 to 1.92 wherein the power outlets comprise one or more DC power outlets.

1.94 An apparatus according to any one of Embodiments 1.1 to 1.93 wherein the power outlets comprise one or more USB power outlets. 1.95 An apparatus according to Embodiment 1.92 wherein a portion of the power output from the PEM cell is converted via a DC/AC power inverter to provide an AC output to one or more of the power outlets and a further portion of the power output from the PEM cell is provided to a DC power outlet. 1.96 An apparatus according to any one of Embodiments 1.1 to 1.95 which comprises a voltage increasing device to increase the voltage of the power output from the hydrogen fuel cell to a power output suitable for an AC mains power outlet (e.g. 115V or 240V).

1.97 An apparatus according to Embodiment 1.96 wherein the voltage increasing device comprises one or more capacitors. The apparatus typically comprises one or more electronic controllers that control the operation of the apparatus. The electronic controller is operatively linked to an on-off mechanism that controls the start-up of the apparatus and to the various electronic and electro-mechanical devices (e.g. pumps) and sensors (for example, pressure or temperature sensors) that are required for operation of the apparatus. The electronic controller is programmed to control the flow of the liquid reactant to the chemical reactor so that pressure and/or temperature inside the reactor do not exceed pre-determined values and, more particularly, do not exceed safe limits.

The electronic controller is linked to one or more user input devices that allow the user to control the apparatus. For example, the user input device may allow the user to start or stop pumping of the pumps, and therefore start or stop production of hydrogen/electricity. The user input device may also or instead be used to select a desired hydrogen pressure output or electrical power output of the apparatus. Typically, the user input device takes the form of one or more buttons or switches, and/or a touch screen computer interface.

One or more information output devices may be provided for providing feedback regarding the operation of the apparatus to the user. The information output device can take the form of a display screen and/or can comprise one or more light-emitting devices, such as bulbs or light emitting diodes. One or more sound emitting devices may also be provided as an audible information output device (e.g. an alarm signal).

The apparatus typically comprises one or more on-board (typically rechargeable) power sources such as batteries to provide the electrical power needed to start-up the apparatus, and in particular to power the pumps, the electronic controller, the user input devices, the output devices and the sensors. Once the apparatus has started up and the generation of hydrogen and electricity has commenced, a proportion of the electricity generated is used to recharge the batteries, a proportion is used in the operation of the apparatus and the remainder can be made available to users of the apparatus via the power outlets.

The apparatus of the invention comprises a housing, within which are contained the hydrogen fuel cell, chemical reactor, electronic components and control circuitry and other components that enable the chemical reactor and fuel cell to function and provide a supply of electricity. The housing may comprise a base and one or more panels secured to the base. Within the housing, one or more frames or supporting members may be provided to hold the components of the apparatus in place. The one or more panels are typically formed by moulding from a suitable mouldable plastics material such as polypropylene.

Access to the interior of the housing may be restricted by the use of locks or security screws or bolts to fasten elements of the housing that would otherwise be removable to give access to the housing interior. Alternatively, or additionally, openable or removable elements of the housing may be secured by means of tamper evident fastenings that indicate whether the housing has been opened. For example, the tamper evident fastenings can take the form of fastenings (e.g. frangible clips) that are designed to break when an element of the housing (e.g. a panel) is removed or opened. Although access to the interior of the housing may be restricted, access to the interior of the reactor is permitted to allow removal and replacement or refilling of the removable liner. The upper body section of the reactor is therefore typically accessible from the exterior of the housing. This can be accomplished, for example, by means of an opening in the housing (e.g. in an upper surface thereof) through which the upper body section of the reactor protrudes.

Other components of the apparatus that are accessible from the housing exterior include control elements such as switches, touch screens, control pads, visual displays and power outlets. The housing may also be provided with a water inlet through which water can be introduced to replenish the water in the water reservoir. The water inlet is typically provided with a cap or stopper that can be removed to fill the reservoir and then replaced. The operation of the apparatus typically involves the generation of heat and means are therefore provided for removing heat from the interior of the housing and shielding heat- sensitive components of the apparatus from heat. The apparatus may therefore include one or more fans for drawing air through the apparatus and expelling hot air. The housing is therefore typically provided with air vents to allow hot air to be vented to the exterior and cool air drawn into the housing.

The apparatus of the invention comprises a removable liner which is located inside the reaction chamber and is supported within the lower body section. The removable liner is capable of holding liquid and containing one or more reactants that react in the presence of water to form hydrogen gas, and is removable from the reaction chamber when the upper and lower body sections are separated.

The removable liner prevents or minimises the likelihood of reactants coming into contact with the interior surfaces of the reaction chamber. The reactants are introduced into the removable liner, either before or after the liner has been placed inside the reactor, and the reaction takes place in the liner. Once reaction between the reactants has been completed, the upper body section of the reactor can be removed or opened and the removable liner removed. The liner can then either be discarded, or cleaned for subsequent re-use.

The removable liner may be pre-filled with one or more reactants (typically solid reactants) before placing inside the reaction chamber. The solid reactants may be provided in a sealed cartridge comprising a removable liner and a lid. The lid is wholly or partly removed, or the liner (liner wall or lid) is punctured before inserting the liner into the reactor. The lid provides a water-tight seal which prevents the ingress of moisture into the liner. The lid may be take the form of a cap, e.g. formed from a plastics or metal material, which can be secured to the liner by means of a screw thread, friction fit or snap fit. Alternatively, the lid can take the form of a covering foil top or polymeric membrane which can be glued or heat sealed in place. The lid can therefore be easily fully or partly removed by the user before use of the liner.

In use, where the liner has a lid, this is wholly or partially removed before the removable liner is placed inside the reaction chamber. Alternatively, an intact sealed liner may be introduced into the reaction chamber in such a way that the liner is punctured, or an opening in the liner is created, as the liner is placed in the reaction chamber or as the upper and lower body sections are connected together. Once the liner or removable liner has been placed in the reaction chamber, the reactor is sealed by connecting the upper and lower body section together. The apparatus can then be switched on and started up and the closable openings in the wall separating the upper and lower body sections opened to allow the liquid reactant or liquid reaction medium to pass into the removable liner. The reactants react together to generate hydrogen gas which passes through the gas outlet conduit and thence on to a hydrogen fuel cell (PEM cell) which generates electricity from the hydrogen.

The apparatuses of the present invention produce hydrogen at low pressures, and in particular pressures of up to about 12 bar. More particularly, the apparatuses of the invention can generate hydrogen at pressures in the range (i) 0.5 Bar to 12 Bar; or (ii) 0.5 bar to 10 Bar; or (iii) 0.5 Bar to 8 Bar; or (iv) 0.5 Bar to 7 Bar; or (v) 0.5 Bar to 6 Bar; or (vi) 0.5 Bar to 5 Bar; or (vii) 0.5 Bar to 3 Bar. The pressures of hydrogen generated by the apparatus of the can be controlled by, inter alia, the amounts of reactants used in a given reaction and, the manner in which they are presented. The apparatus of the invention is generally portable.

The term "portable" as used herein refers to an apparatus having a weight and dimensions that enable it to be moved (e.g. lifted and carried) comfortably by one or two people of average strength. Thus, for example, a portable apparatus of the invention can weigh up to about 25 kg when empty of reactants. More typically, the portable apparatus will have an empty weight of up to 20 kg, for example up to 15 kg. In one embodiment, the apparatus has an empty weight of 5 kg to 20kg.

The dimensions of portable apparatuses of the invention may be such that it has a maximum width of up to 1 metre, a maximum length of up to 1 metres and a maximum height of up to 1 metres. More usually, the dimensions of the portable apparatus of the invention may be such that it has a maximum width of up to 0.75 metre, a maximum length of up to 0.75 metres and a maximum height of up to 0.75 metre.

In a further aspect of the invention (Embodiment 2.1 ), there is provided a chemical reactor for producing hydrogen, the chemical reactor comprising: upper and lower body sections connected together so as to enclose a reaction chamber, the upper and lower body sections being separable to allow the introduction of one or more chemical reactants and reconnectable to form a gas-tight seal therebetween; the upper body section being capable of containing a liquid reactant or a liquid reaction medium;

a gas outlet through which hydrogen gas can exit the reactor;

an upwardly extending gas conduit located centrally within the lower body section, the upwardly extending gas conduit serving to connect the reaction chamber to the gas outlet;

one or more closable openings being provided in a wall separating the upper and lower body sections (e.g. in a lower wall of the upper body section) for introducing the liquid reactant or liquid reaction medium into the removable liner such that a chemical reaction can take place between chemical reactants in the removable liner to produce hydrogen; wherein an annular space is present in the lower body section between a radially inner wall of the lower body section and a radially outer wall of the upwardly extending gas conduit, in which annular space, a removable liner, for example a removable liner as described in any one of Embodiments 1.53 to 1.77 and 10.2 to 10.6, can be

accommodated.

In particular embodiments (collectively referred to for convenience as Embodiment 2.2), the chemical reactor is as defined in any one of Embodiments 1.1 to 1.52.

In a further aspect of the invention (Embodiment 3.1 ) there is provided an apparatus for generating electricity, the apparatus comprising:

a housing and, mounted in the housing, a hydrogen fuel cell and docking base unit to which a reactor for producing hydrogen to supply the fuel cell to enable the fuel cell to generate electricity can be removably connected; and

a power output to which an electrical power-consuming device can be attached; wherein the chemical reactor comprises:

upper and lower body sections connected together so as to enclose a reaction chamber, the upper and lower body sections being separable to allow the introduction of one or more chemical reactants and reconnectable to form a gas-tight seal therebetween; the upper body section being capable of containing a liquid reactant or a liquid reaction medium; a gas outlet through which hydrogen gas can exit the reactor;

a removable liner disposed inside the reaction chamber and being supported within the lower body section, the removable liner being constructed so as to be able to contain a liquid reaction medium and hold one or more chemical reactants therein; the removable liner being removable from the reaction chamber when the upper and lower body sections are separated; and

one or more closable openings being provided in a wall separating the upper and lower body sections (e.g. in a lower wall of the upper body section) for introducing the liquid reactant or liquid reaction medium into the removable liner such that a chemical reaction can take place between chemical reactants in the removable liner to produce hydrogen.

In particular embodiments (collectively referred to for convenience as Embodiment 3.2), the chemical reactor is as defined in any one of Embodiments 1.1 to 1.52 and/or the removable liner is as defined in any one of Embodiments 1.53 to 1.77 and 10.2 to 10.6.

In a further aspect of the invention (Embodiment 4.1 ) there is provided an apparatus for generating electricity, the apparatus comprising:

a housing and, mounted in the housing, a hydrogen fuel cell and docking base unit to which a chemical reactor for producing hydrogen to supply the fuel cell to enable the fuel cell to generate electricity is removably connected; and

a power output to which an electrical power-consuming device can be attached; wherein the chemical reactor comprises:

upper and lower body sections connected together so as to enclose a reaction chamber, the upper and lower body sections being separable to allow the introduction of one or more chemical reactants and reconnectable to form a gas-tight seal therebetween; the upper body section being capable of containing a liquid reactant or a liquid reaction medium;

a gas outlet through which hydrogen gas can exit the reactor;

and

one or more closable openings being provided in a wall separating the upper and lower body sections (e.g. in a lower wall of the upper body section) for introducing the liquid reactant or liquid reaction medium into the lower body section such that a chemical reaction can take place between chemical reactants in the lower body section to produce hydrogen. In particular embodiments (collectively referred to for convenience as Embodiment 4.2), the chemical reactor is as defined in any one of Embodiments 1.1 to 1.52 and 1.78 to 1.97.

Inn further embodiments (collectively referred to for convenience as Embodiment 4.3), the apparatus may include a removable liner as defined in any one of Embodiments 1.1 , 1.53 to 1.77 and 10.2 to 10.6.

In a further aspect of the invention (Embodiment 5.1 ) there is provided an apparatus for generating electricity, the apparatus comprising:

a housing and, mounted in the housing, a hydrogen fuel cell and docking base unit to which a reactor for producing hydrogen to supply the fuel cell to enable the fuel cell to generate electricity is removably connected; and

a power output to which an electrical power-consuming device can be attached; wherein the chemical reactor comprises:

upper and lower body sections connected together so as to enclose a reaction chamber, the upper and lower body sections being separable to allow the introduction of one or more chemical reactants and reconnectable to form a gas-tight seal therebetween; a gas outlet through which hydrogen gas can exit the reactor; and

a removable liner disposed inside the reaction chamber and being supported within the lower body section, the removable liner being constructed so as to be able to contain a liquid reaction medium and hold one or more chemical reactants therein; the removable liner being removable from the reaction chamber when the upper and lower body sections are separated.

In particular embodiments (collectively referred to for convenience as Embodiment 5.2), the chemical reactor is as defined in any one of Embodiments 1.1 to 1.52 and/or the removable liner is as defined in any one of Embodiments 1.53 to 1.77 and 10.2 to 10.6.

In a further aspect (Embodiment 6.1 ), the invention provides a combination of (i) a chemical reactor as described herein and as defined in Embodiment 2.1 or Embodiment 2.2 and (ii) a removable liner as described herein and as defined in any one of Embodiments 1.53 to 1.77 and 10.2 to 10.6.

The invention also provides (as Embodiment 6.1 ) a method of producing hydrogen gas using an apparatus as described herein and as defined in any one of Embodiments 1.1 to 1 .97, which method comprises introducing one or more reactants and a liquid reactant or a liquid reaction medium into the chemical reactor to bring about a reaction to generate hydrogen, and drawing off hydrogen thus generated through the hydrogen gas outlet.

The invention also provides (as Embodiment 7.1 ), a method of generating hydrogen gas, the method comprising:

(i) providing a liner (optionally as described herein and as defined in any one of Embodiments 1.53 to 1 .77 and 10.2 to 10.6) containing one or more reactants which react in the presence of water to form hydrogen gas;

(ii) placing the liner into a chemical reactor comprising:

upper and lower body sections connected together so as to enclose a reaction chamber, the upper and lower body sections being separable to allow the introduction of one or more chemical reactants and reconnectable to form a gas-tight seal therebetween;

the upper body section containing a liquid storage area capable of serving as a reservoir for a liquid reactant or a liquid reaction medium;

an upwardly extending gas outlet conduit through which hydrogen gas can exit the reactor; the upwardly extending gas outlet being located centrally within the lower body section;

the liner being placed in the reactor so that it resides into the lower body section of the reactor;

(iii) connecting the upper and lower body sections to form a gas-tight seal therebetween;

(v) facilitating the introduction of an aqueous liquid from the upper body section to the lower body section so that it falls into the opened liner, thereby to react with the aqueous liquid to generate hydrogen gas. In further embodiments (Embodiments 7.2 to 7.4), the invention provides:

7.2 A method as defined in Embodiment 7.1 , wherein the liner is provided as a sealed liner which is opened prior to placing it into the reactor.

7.3 A method as defined in Embodiment 7.2, wherein the liner comprises a removable liner and a lid, which lid is removed prior to placing the removable liner in the reactor and wherein the removable liner is formed so as to be able to contain the reactants and the aqueous liquid and accommodate a reaction between the reactants and aqueous liquid, and be removable after completion of the reaction.

7.4 A method as defined in Embodiment 7.3 wherein the liner comprises a removable liner as defined in any one of Embodiments 1.53 to 1 .77 and 10.2 to 10.6. In a further aspect of the invention (Embodiment 8.1 ), there is a provided an apparatus for generating electricity, the apparatus comprising:

a housing and, mounted in the housing, a PEM hydrogen fuel cell and a chemical reactor for producing hydrogen to supply the fuel cell to enable the fuel cell to generate electricity, the PEM fuel cell being of a type that operates a hydrogen purge at

predetermined (e.g. regular) intervals; and

a power outlet to which an electrical power-consuming device can be attached; wherein the chemical reactor comprises:

upper and lower body sections connected together so as to enclose a reaction chamber, the upper and lower body sections being separable to allow the introduction of one or more chemical reactants into the reaction chamber and being reconnectable to form a gas-tight seal therebetween;

the upper body section being capable of containing a liquid reactant or a liquid reaction medium;

one or more closable openings in a wall separating the upper and lower body sections, the closable openings being located above the removable liner so that liquid reactant or liquid reaction medium can fall through the openings into the removable liner such that a chemical reaction can take place between chemical reactants in the removable liner to produce hydrogen; and

a gas outlet through which hydrogen gas can exit the reaction chamber for onward flow to the hydrogen fuel cell; and

one or more charge storage devices (e.g. as defined in any one of Embodiments 1.83 to 1.90) which release charge when there is an interruption of power output from the PEM cell as a result of the hydrogen purge; the apparatus being programmed to provide a continuous supply of electricity to the power outlet by a combination of electricity supplied by the PEM fuel cell and charge released from the one or more charge storage devices.

In particular embodiments (collectively referred to for convenience as Embodiment 8.2), the chemical reactor is as defined in any one of Embodiments 1.1 to 1.52.

In further embodiments and/or the removable liner is as defined in any one of Embodiments (collectively referred to for convenience as Embodiment 8.3), the apparatus may comprise a removable liner as defined in any one of Embodiments 1.1 , 1.53 to 1.77 and 10.2 to 10.6.

In a further aspect of the invention (Embodiment 9.1 ), there is a provided an apparatus for generating electricity, the apparatus comprising:

a housing and, mounted in the housing, a PEM hydrogen fuel cell and a chemical reactor for producing hydrogen to supply the fuel cell to enable the fuel cell to generate electricity, the PEM fuel cell of a type that operates a hydrogen purge at predetermined (e.g. regular) intervals; and

a power outlet to which an electrical power-consuming device can be attached; wherein the apparatus comprises one or more charge storage devices (e.g. as defined in any one of Embodiments 1 .83 to 1 .90) which release charge when there is an interruption of power output from the PEM cell as a result of the hydrogen purge;

the apparatus being programmed to provide a continuous supply of electricity to the power outlet by a combination of electricity supplied by the PEM fuel cell and charge released from the one or more charge storage devices.

In particular embodiments (collectively referred to for convenience as Embodiment 9.2), the chemical reactor is as defined in any one of Embodiments 1.1 to 1.52. In further embodiments and/or the removable liner is as defined in any one of Embodiments (collectively referred to for convenience as Embodiment 9.3), the apparatus may comprise a removable liner as defined in any one of Embodiments 1.1 , 1.53 to 1.77 and 10.2 to 10.6. Our earlier International patent application (PCT/EP2017/066839) discloses a hydrogen generating apparatus comprising a reactor vessel and a docking base unit upon which the reactor base is supported. The reactor vessel disclosed in PCT/EP2017/066839 may be provided with a gas-permeable (and optionally water permeable) liner, for example in the general form of a sock, may be located inside the lower reactor body portion so that when the reactants drop into the lower reactor body portion, the reaction to produce hydrogen takes place within the liner. It is further disclosed in PCT/EP2017/066839 that the liner can be constructed such that before upper and lower reactor body portions are secured together, the liner or sock can be loosely positioned in and around the inside of the lower reactor body portion and over a central exit tube in the lower reactor body portion.

The combination of reactor vessel, docking base and a liner disclosed in

PCT/EP2017/066839 is not intended to be within the scope of the present invention.

Accordingly, in a further embodiment (Embodiment 10.1 ), there is provided an invention as defined in any one of Embodiments 1.1 to 9.2 wherein the invention is other than one comprising or making use of an apparatus (or reactor) comprising:

(a) a reactor vessel within which a reaction between two or more chemical reactants can take place to generate hydrogen, the reactor vessel having a valved outlet through which hydrogen can be drawn off; and

(b) a docking base unit upon which the reactor vessel is supported and to which the reactor vessel is removably attached, the docking base unit having a valve-engaging element which engages the valved outlet of the reactor vessel so as to open the valved outlet to allow hydrogen to be drawn off when the reactor vessel is placed on the docking base unit.

The liner (e.g. sock) disclosed in PCT/EP2017/066839 is disclosed as being formed so that it can be loosely positioned in and around the inside of the lower reactor body portion and over a central exit tube in the lower reactor body portion.

The liner of the present invention is distinguished from the liner in PCT/EP2017/066839 in that the liner of the invention typically has walls that are sufficiently rigid or stiff that they are self-supporting and maintain the shape of the liner. The liners may therefore be formed from moulded, formed, 3d-printed or machined plastics materials or from a metal (typically one which does not react with the reactants).

Accordingly, in further embodiments (10.2 to 10.6), the invention provides:

10.2 An invention as defined in any one of Embodiments 1.1 to 9.2 wherein the removable liner has walls that are sufficiently rigid or stiff that they are self-supporting and maintain the shape of the liner, for example wherein the liner is other than a sock.

10.3 An invention as defined in any one of Embodiments 1.1 to 9.2 and 10.2 wherein the liner is formed by a method other than knitting or weaving of textile fibres.

10.4 An invention as defined in any one of Embodiments 1.1 to 9.2 and 10.2 wherein the liner is formed from a material other than cloth or a material obtained by knitting or weaving of textile fibres.

10.5 An invention as defined in any one of Embodiments 1.1 to 9.2 wherein the removable liner is formed from moulded, formed, 3d-printed or machined plastics materials or from a metal. 10.6 An invention according to Embodiment 10.5 wherein the removable liner is formed from a mouldable plastics material.

Further aspects and embodiments of the invention will be apparent from the specific description below and the drawings

Brief Description of the Drawings Figure 1 is a perspective view of the reactor according to a first embodiment of the invention.

Figure 2 is a side view of the reactor shown in Figure 1.

Figure 3 is a cross-sectional view of the reactor along line A-A in Figure 2.

Figure 4 is a perspective view of the lower section of the reactor vessel. Figure 5 is a cross-sectional view of the lower body section of the reactor vessel with the liner removed.

Figure 6 is a perspective view of the docking base of the reactor shown in Figures 1 to 3.

Figure 7 is a cross-sectional view of the upper section of the reactor vessel. Figure 8 is a top down view of valve plate forming part of the reactor vessel of Figures 1 to 3.

Figure 9A is a perspective view of one type of liner for use with the apparatus of the invention.

Figure 9B is a top-down view of the liner shown in Figure 9A. Figure 10 is a perspective view of a further type of liner for use with the apparatus of the invention.

Figure 1 1 is a schematic drawing showing an apparatus for generating electricity comprising a reactor of the invention.

Detailed Description of the Invention The invention will now be illustrated but not limited by reference to the specific

embodiments shown in the drawings Figures 1 to 1 1.

The apparatus of the invention comprises an outer casing within which are contained a reactor for generating hydrogen and a PEM fuel cell that consumes the hydrogen to produce electricity. Also contained within the outer casing are a water trap for removing water from the hydrogen gas produced by the reactor before the hydrogen enters the fuel cell, a number of fans for cooling the interior of the casing, and various printed circuit boards and associated electronic components and devices that control the operation of the apparatus.

Figures 1 to 8 are views of the reactor or individual components of the reactor, Figures 9A, 9B and 10 show removable liners for containing reactants that react in water to form hydrogen, and Figure 1 1 is a schematic diagram showing the internal components of the apparatus.

Figures 1 to 3 show a reactor (10) according to a first embodiment of the invention. When assembled, the reactor (10) comprises upper (16) and lower (12) reactor body sections formed from a suitable material such as stainless steel. Figures 1 to 3 also show the reactor fitted into a docking base (14).

The reactor comprises a generally cylindrical lower body section (12) and an upper body section (16), both formed from a suitable metal such as stainless steel. The upper (16) and lower (12) body portions can each be formed, for example, by welding a stainless steel cylinder (which can be cut from a length of stainless steel tubing) to a machined stainless steel base and/or top piece. Alternatively, the body portions can be machined from a block of stainless steel. In a further alternative, the body portions can be formed by deep drawing from a blank of stainless steel sheet. As an alternative to a metal such as steel, the body portions can be formed from a suitably tough and chemically resistant (to the reactants) plastics material, for example by injection moulding.

The lower body section (12) has an internal thread at its upper end which engages a complementary external thread extending around the lower end of the upper body section (16). A gasket (22) formed from a suitable gas-tight sealing material is disposed between confronting surfaces of the upper and lower body sections so that a gas-tight connection can be formed by screwing the upper and lower body sections together.

Located centrally within lower body section (12) is a central exit tube (26) which extends upwardly from the base of the body section (12). The central exit tube (26) functions as a gas outlet conduit and provides an outlet for gas produced within the reactor vessel. The upper end of central exit tube (26) is provided with a valve assembly which can be opened or closed to allow or prevent gas escape from the reactor vessel. The valve assembly comprises a spring-loaded plunger (30) which is located inside the central exit tube (26). The spring-loaded plunger (30) has a valve member (28) formed from steel mounted on its upper end. In the closed condition, the valve member (28) engages a fluoroelastomer (Viton®) O-ring seal (29) located in a groove on an upper surface of the central exit tube (26) to create a gas tight seal. When the reactor vessel (12) is fitted onto the docking base (14), an upstanding rod (38) (which constitutes a valve-engaging element) in the docking base (14) enters the lower end of the central exit tube and is urged against the plunger (30), thereby pushing the plunger upwards against the restoring force of the spring (31 ) and displacing the valve member (28) from its sealing position on the top of the central exit to provide fluid communication between the interior of the reactor vessel and the central exit tube. Hydrogen generated by the reaction of the reactants in the reactor vessel (12) can then pass out of the vessel through the exit tube (30). When the reactor vessel (12) is removed from the docking base (14), the spring-loaded plunger (30) springs back into place thereby restoring the seal between the valve member (28) and the top of the exit tube (26).

A removable liner (200) containing solid reactants (not shown) is located inside the lower reactor body section (12). The structure of the liner is described in more detail below.

The liner (200) fits in the lower body section of the reactor such that the central exit tube (26) extends up through a central tubular structure (200b) in the liner, as shown in Figure 3. The inner surface of the cylindrical wall of the lower body section (12) is provided with a guide protrusion (40) which slots into channel (200d) in the liner (200) and thereby ensures that the liner is placed into the lower body section in the correct orientation.

With reference to Figure 6, the docking base (14) has a circular floor and a cylindrical side wall (32), which together with the base of the lower body section (12), defines a lower gas exit chamber (37). The cylindrical side wall (32) has an enlarged diameter region (34) which forms a seat for the lower body section (12) of the reactor vessel. The docking base floor has a central shaft (38) extending from the centre point thereof. When the lower body section (12) of the reactor vessel is placed in the docking base (14), the central shaft (38) aligns with an opening in the base of the reactor vessel which leads to the central exit tube (30) in the reactor vessel.

The lower body section (12) and the docking base can be secured together by means of four bosses (36) which protrude inwardly from the enlarged diameter region (34) of the side wall (32) and which engage recessed tracks (24) in the lower rim (12a) of the upper body section (12). The tracks (24) are angled for most of their length but have a horizontal or very slightly downturned end region (24a) which is delimited from the angled section of the track by a high point (24b). To attach the reactor to the docking body, the reactor is placed in the docking base so that the central shaft (38) aligns with the hole in the base of the reactor vessel and the bosses (36) locate in the open ends of the angled tracks (24). The reactor vessel is then rotated so that the bosses (36) move along the tracks thereby drawing the reactor and docking base together. As the bosses (36) approach the end of the angled regions of the tracks (24), further movement is opposed by the resilience of an elastomeric fluoroelastomer (Viton®) O-ring (35) which sits in an annular groove at the foot of the enlarged diameter region (34) of the docking base. Further rotation of the reactor urges bosses (36) over the high point (24b) and into the horizontal or slightly downturned end region (24a) against the resistance of the O-ring, so that the lugs click into place and hold the reactor vessel tightly against the docking body. By virtue of the O-ring (35), the union between the reactor and the docking base is substantially gas-tight.

The docking base is provided with an opening in which an elbow connector (20) is secured, e.g. by means of a threaded attachment. The elbow connector (20), which thus functions as an exit port, is connected via tubing (not shown) to a water removing device (not shown) and pressure reducer (also not shown) and then to a hydrogen consuming device such as a fuel cell. Thus, hydrogen generated within the reactor can exit the reactor through the central exit tube (26) and into the lower gas exit chamber (37) and thence on towards the fuel cell.

The upper body section (16) of the reactor vessel is of generally cylindrical drum form and has circular upper (16a) and lower (16b) walls linked by a cylindrical side wall (16c). A rotatable shaft (56) extends between the upper (16a) and lower (16b) walls and is rotatably mounted at the two ends thereof in gland seals (17) and (19) formed in the upper (16a) and lower (16b) walls. The gland seals contain O-rings formed from an elastomeric

fluoroelastomer (Viton®) which provide substantially gas tight seals whilst allowing rotation of the shaft (56). A knob (18) is secured to the upper end of the shaft (56) by means of a screw (58). The knob (18) facilitates rotation of the shaft (56). A stopper plate (46) is attached to the lower end of the shaft (56) by means of a screw (60). The upper body section (16) is also provided with a carry handle (62) which is connected to the upper body section by a pair of screws (63) at diametrically opposed positions on the upper body section. The lower wall of the upper reactor body section has a water filling-hole (66), a water- release hole (68) and a breather hole (70). The water filling hole (66) is larger in diameter than the water release hole (68). In the illustrated embodiment, the water filling hole and water-release hole are diametrically opposite one another, with respect to the central shaft (56). The diameter of the water-release hole is selected so as to limit the flow of liquid (e.g. water) into the lower body section to a desired maximum flow rate. For example, the water- release hole (68) may have a diameter of 0.0197 inches (0.5 mm). In this way, water from the reservoir in the upper body section can be introduced into the liner in the lower body section in a dropwise controlled manner.

The opening and closing of the holes in the lower wall of the upper body section is controlled by the stopper plate (46). As shown in Figure 8, the stopper plate (46) has a central hole (46c) which receives central shaft (56). The stopper plate has a pair of arms (46a, 46b) extending in opposite directions from the central hole (46c). Attached to the stopper plate (46) is a sealing gasket (48) having a pair of sealing regions (48a) and (48b) linked by webs to a central sealing region (48c). The smaller sealing region (48a) has an oval shape whereas the larger sealing region (448b) has a distorted oval or "jelly-bean" shape.

The stopper plate (46) can be rotated, by rotation of knob (18), through a number of different orientations. In a first orientation, the larger sealing region (48b) covers the water filling hole and the smaller sealing region (48a) covers the water release hole. In this configuration, liquid cannot enter or leave the upper reactor body portion as both holes are sealed by the gasket seals on the stopper plate.

From the first orientation, the stopper plate can be rotated through about 30° to a second orientation in which the larger sealing region (48b) still covers the water filling-hole, but the water release hole is uncovered to allow liquid to flow from the upper reactor body section into the lower reactor body section and to react with the reactants in the liner. The stopper plate can be rotated to a third orientation in which both the water filling hole and the water release hole are opened. This allows the upper reactor body section to be refilled with liquid via the water filling hole when the upper and lower reactor body sections are separated.

The upper body section (16) is also provided with a breather tube (72), which extends from the breather hole (70) in the lower wall of the upper body section to the top of the interior of the upper body section, above the fluid level when the upper body section is filled with the liquid reactant. The breather tube (72) serves to equalise the pressure between the upper and lower body sections to allow the liquid to flow freely from the upper body section to the lower body section. The opening (70) is positioned adjacent the release hole (68), such that when the stopper plate (46) is oriented to prevent liquid from exiting the upper body section through the release hole (68), the hole (70) is also covered.

The top of the lid contains markings (which may be letters, words, numbers or symbols), which align with the various positions of the knob to indicate the orientation of the stopper plate (46) and for example whether the water-filling hole or water-release hole are open or closed.

When assembled, the reactor is sealed as described above to prevent the escape of generated hydrogen from the reactor. In addition, also as described above, the docking base (14) is provided with a fluoroelastomer (Viton®) O-ring (35) to form a sealed connection between the reactor vessel and the docking base. Therefore, the hydrogen generated in the reactor can only exit the reactor through the central exit tube (26) and the exit port (20).

In use, the upper and lower reactor body sections are unscrewed and separated and a liner (200) loaded with one or more reactants suitable for generating hydrogen is placed into the lower body section (12). The reactant may be added to the liner as a powder or in a sachet which degrades when contacted with water.

The reactants can be any of a number of different pairs of reactants that react together to form hydrogen as described above but, in a particular embodiment, the reactants are aluminium powder and sodium hydroxide.

An aqueous reaction medium (which could be plain water or another aqueous medium) is introduced so that it partly fills the upper reactor body section through water filling hole (66). The upper and lower body sections are then screwed together to form a sealed reactor vessel in which the only exit for hydrogen gas is the valved opening. No other inlets or outlets for reactants or reaction products are provided.

Once the upper and lower reactor body sections have been screwed together, the knob (18) can be rotated thereby rotating the stopper plate so that the stopper plate still obscures the water filling hole (66), but uncovers the water-release hole (68) allowing the liquid to drip into the lower body section of the reactor and react with the reactant in the liner (200). The mixing of the reactants and liquid and hence the rate of reaction can be assisted by shaking the reactor vessel. As the reaction takes places in the liner, contact between the reactants and the body of the reactor vessel itself is minimised thereby reducing or avoiding the need to clean the interior of the body of the reactor vessel after use.

Once hydrogen formation has been initiated, the reactor vessel can be placed on the docking base so that the rod (38) engages the plunger (30), pushing it upwardly to lift the valve member (28) off its seat on the top edge of the central exit tube (26). Hydrogen can then flow out through the central exit tube (36) and into the lower chamber (37) between the reactor vessel and docking base and then out though exit port (20) to a hydrogen- consuming device such as a fuel cell.

The hydrogen for the PEM fuel cell is generated by reaction of reactants in the liner (200) with or in water entering the lower body section (12) from the upper body section (16). Examples of cartridges for use with the apparatus of the invention can be seen in Figures 9A and 9B and Figure 10. In general, the liners have a cylindrical outer wall and a tubular structure extending upwardly through the centre of the liner to define an annular space between the outer wall and tubular structure for containing reactants. The diameter of the internal bore of the central tubular structure is such that it can fit over and about the central exit tube (26) in the reactor.

The liner shown in Figures 9A and 9B (210) has a cylindrical outer wall (21 1 ) and a concentric inner tubular structure (212), both of which are connected to (e.g. by virtue of being integrally moulded with) a circular base piece. Together, the upper surface of the base piece, the radially outer surface of the tubular structure (212) and the radially inner surface of the outer wall (21 1 ) form an annular reactant-containing space.

The liner (210) has a groove or channel (213) down its side extending from the bottom of the liner up the majority of the height of the liner. The channel can engage with a formation in the reactor body (not shown) to act as a locating means to ensure that the liner (200) can only be placed in the reactor body (12) in a single rotational orientation. The liner (210) is typically formed (e.g. moulded) from a plastics material, for example a biodegradable plastic (e.g. a nylon/polylactic acid mix).

In this embodiment, the liners are filled with a mixed of powdered aluminium and powdered sodium hydroxide. In the presence of water, the aluminium reacts with the water to produce hydrogen gas and aluminium hydroxide, with the sodium hydroxide acting as a catalyst.

A liner (220) according to a further embodiment of the invention is shown in Figure 10. In this embodiment, the liner (220 has a cylindrical outer wall (221 ), an inner wall defined by a concentric central tubular structure (222) and a base (not shown). The central tubular structure is hollow and is open at both upper and lower ends, the open lower end being aligned with an opening in the base of the liner. The inner diameter of the central tubular structure is such that it can fit over and about the central exit tube (26) in the reactor.

In contrast to the liner shown in Figures 9A and 9B, the liner (220) has a plurality of partition walls (223) radiating outwardly from the inner wall (222) to the outer wall (221 ) of the liner. The partition walls (223) partition the annular space between the inner wall (222) and the outer wall (221 ) into a number of discrete reaction compartments, each compartment containing a dose of the solid reactants. When placed in the reactor (10), one of the reaction compartments (the "first compartment") is situated below the water-release hole (68). When water enters the lower body section (16), it falls into the first compartment and, as further water enters the liner, the first compartment fills and the water can overflow into an adjacent compartment. This allows for a controlled reaction between the solid reactants in the liner and the water in a series of steps, as each compartment in turn fills with water and reaction is initiated. In this way, immediate reaction of water with all of the contents of the liner is avoided. As can be seen in Figure 10, one of the partition walls, namely the wall labelled (224), is of a greater height that the others. Thus, partition wall (224) has a height equal to the height of the inner (222) and outer (221 ) walls, whereas the other partition walls (223) have a reduced height. The water-release hole (68) is typically positioned so that it is situated above one of the two compartments that are defined by the higher wall. This means that when the first compartment fills, the water can only overflow in a single direction and therefore the compartments fill one at a time starting from a compartment adjacent the highest wall in either a clockwise or anticlockwise direction.

As with the liner shown in Figures 9A and 9B, the liner of Figure 10 is typically formed (e.g. by moulding) from a plastics material such as a biodegradable plastics material (e.g. a nylon/polylactic acid mix), and is filled with a suitable reactant or mixture of reactants, such as a mixture of powdered aluminium and powdered sodium hydroxide. In the presence of water, the aluminium reacts with the water to produce hydrogen gas and aluminium hydroxide, with the sodium hydroxide acting as a catalyst.

The liner may be provided in the form of a cartridge comprising the liner pre-filled with reactants and sealed with a lid to prevent the ingress of moisture prior to use. A polymeric film membrane may also be heat-sealed over the mouth of the liner to provide further protection against moisture penetration. The lid and polymeric film membrane are removed prior to placing the liner in the reaction chamber.

Although in the embodiment described herein, water is used as a liquid reagent to react with the solid reactants in the liner, it should be understood that other liquids (typically aqueous liquids) can be used provided that they react with the solid reactants to form hydrogen gas.

In addition, the reactants can be any of a number of different pairs of reactants that react (with a liquid reaction medium, e.g. water) to form hydrogen as described above. However, in a particular embodiment, the reactants are aluminium powder and sodium hydroxide.

In addition, although the liners can be provided as sealed pre-filled cartridges, the reactants can instead be provided in the form of sachets that can be opened and the contents poured into an empty liner prior to use. In a further alternative, water-soluble pouches or sachets or other water soluble or disintegratable containment forms containing reactants may be provided for addition to an empty liner prior to use.

The assembled reactor can be used in isolation as a supply of hydrogen or used in conjunction with a hydrogen fuel cell for the generation of electricity.

When the reactor is used in conjunction with a hydrogen fuel cell, the reactor can be placed in a housing, which contains one or more fuel cells, for example, proton-exchange membrane (PEM) fuel cells, in order to allow the hydrogen generated in the reactor to be converted to electrical power.

Figure 1 1 is a schematic drawing showing the components of an apparatus for generating electricity comprising a reactor (10) as described above. In Figure 11 , bold lines show connections which convey hydrogen gas between components and dotted lines show connections which conduct electricity between components.

Hydrogen gas is produced in the reactor (10) through the reaction of the solid reactants in the liner with water or another aqueous liquid. The gas then exits the reactor through central exit tube (26) and exit port (20). A water trap (102) is connected to the exit port (20) via a length of tubing. The water trap removes moisture from the hydrogen gas generated in the reactor (10). Downstream of the water trap (102) is a pressure reducer (104). The pressure reducer (104) limits the pressure of hydrogen to approximately 0.5 - 7 psi (0.035 bar to 0.5 bar).

The reduced pressure gas enters a proton-exchange membrane (PEM) fuel cell (106) via a solenoid valve. The PEM cell consumes the hydrogen gas and uses it to generate electricity. The PEM fuel cell purges every 7 seconds and any hydrogen purged is vented to the atmosphere. As the pressure of hydrogen in the PEM cell is low, hydrogen gas can be vented to the atmosphere without risk of combustion. When the fuel cell purges, this leads to an interruption of the electrical output of the PEM cell. Therefore, the apparatus also comprises a series of high-capacity capacitors (108) which store electricity produced by the PEM cell to provide electricity to the power outlet sockets when the fuel cell is purging. The capacitors are able to store 105W for a period of 1 .5 ms. This prevents/reduces fluctuations in electricity supplied to the power outlet sockets as a result of the purge cycle of the PEM cell. A further PCB (not shown) is provided for control of PEM cell (106).

The apparatus comprises an AC-DC power inverter (1 10) to convert the DC current produced by the fuel cell to provide an AC current output which is delivered to the AC mains power outlet sockets (1 14). The DC USB power outlets (1 16) can use DC current generated by the fuel cell without the need for the current to be inverted with inverter (110).

Further capacitors (112) are provided which boost the power output of the PEM cell from 30V to 115V as required for a US mains power outlet (1 14). The apparatus also comprises several cooling fans to prevent the fuel cell and other electronic components of the apparatus from overheating.

The apparatus comprises an onboard power supply, which may take the form of or comprise one or more rechargeable batteries within the casing. The onboard power supply is used to start the electricity-consuming components of the apparatus before hydrogen generation and production of electricity has commenced. Once the apparatus has started producing electricity, a proportion of the electricity is used to power the electricity consuming components, another proportion is used to recharge the onboard power supply and a further proportion is provided to one or more power outlet sockets (114/1 16).

In use, the apparatus is switched on (switch not shown in Figures) and the knob (18) is rotated to open the release hole (68) so that the aqueous reaction medium can enter the lower part of the reactor and react with the reactants as described above. The two reactants (e.g. powdered sodium hydroxide and aluminium powder) are chosen such that when mixed in water they react to form hydrogen gas. The hydrogen gas generated in the reactor vessel exits the reactor vessel through the central exit tube (26) and exit port (20) and flows to the pressure reducer (104) (via a water trap (102). Hydrogen is then directed into the

PEM fuel cell (106), where it is consumed to generate electricity. Where the output from the PEM fuel cell is DC current, the AC-DC power inverter (1 10) converts the DC power generated by the fuel cell to AC power which can then be used as the power source.

Otherwise it is converted into a 12v supply and/or USB electrical supply (1 16). As stated above, a proportion of the electricity produced by the PEM cell can be used to recharge the batteries (although in some embodiments this is not done), and a further proportion of the electricity can be used to power the electricity-consuming devices such as the PCB. The remainder of the electricity generated can be carried by cable (not shown) to a connector (e.g. a plug socket (1 14) or 12v socket or USB ports (116)) for connection to external electrical devices. Control circuitry that controls the operation of the apparatus is able to regulate the power supply by means of super capacitors. Because PEM fuel cells typically expel (purge) a small amount of hydrogen to atmosphere every 7-30 seconds and, while doing so, the PEM automatically drops electric power for perhaps 100ms, this has the effect of interrupting the electricity supply for the end user with the result that the apparatus would shut down before being reset manually. To provide continuity of supply of electricity to run the apparatus and prevent shutting down at each purge, super capacitors (108) are provided within the PCB to bridge the drop in electrical power for the 100ms when the PEM cell is in purge mode.

During operation of the apparatus, despite the presence of the liner, some solid waste products may accumulate in the reactor vessel. At intervals, the upper (16) and lower (12) reactor body portions can be disconnected (e.g. unscrewed) so that the waste products can be removed from the reactor vessel by removal of the liner.

In a variation of the apparatus a recycling system may be provided for recycling hydrogen gas released by the PEM cell during purging. For example, purged hydrogen can be passed through a pressure multiplier and filter (to capture the water contained within the purged hydrogen) and then reintroduced into the gas flow immediately after the pressure reducer. In one embodiment, the purged hydrogen exits the PEM every few seconds at a pressure which is usually in the range from about 1 psi to about 15 psi (the value can vary from one PEM cell to another) for a purge period of 100ms, and the pressure multiplier holds the purged hydrogen in a storage chamber until the pressure has reached a predetermined value (e.g. 14psi) at which point it directs a pulse of hydrogen (e.g. 7psi of hydrogen) into the gas flow immediately after the pressure reducer. The cycle is typically continuous and results in more efficient use of hydrogen generated by the apparatus.

Equivalents It will readily be apparent that numerous modifications and alterations may be made to the specific embodiments of the invention described above without departing from the principles underlying the invention. All such modifications and alterations are intended to be embraced by this application.