Robert H.J. Miros Keith B. Payea

James A. McCrea Brett W. Selvig

CROSS-REFERENCE TO RELATED APPLICATION

[0001] The present application claims priority to U.S. Provisional Application No. 63/266,399, filed January 4, 2022 which is incorporated by reference herein in its entirety.

BACKGROUND

1. Technical Field

[0002] A portable, thermoelectric refrigerator with attendant temperature monitoring and battery life predicting features for the transport of temperature sensitive materials is disclosed.

2. Description of the Related Art

[0003] Various types of portable cooler boxes and refrigerators are available, but the need for controlled temperature delivery systems is present in many fields of use. One of such fields of use is the transport of life saving vaccines to remote locations in the world. If the temperature of vaccines goes too high or drops below freezing, the vaccines can be can permanently inactivated thus rendering them unsafe and/or useless in inoculation against disease. Thus, the need for refrigerating medicines is a serious problem globally, particularly in lesser developed countries and remote parts of the world without consistent electrical power.

[0004] There is a need to monitor the temperature of vaccines as they are in transit. The World Health Organization stipulates that most vaccines are to be kept in a safe, cool range of 2 degrees Celsius to 8 degrees Celsius. The lack of constant, reliable monitoring systems for cooler boxes used in vaccine delivery programs creates uncertainty in the safety of medicines delivered, makes waste in that medicines that are unknown to have been kept within the safe range must be disposed of, and sometimes requires redundant and ineffective cooling methods to assure the safety range is maintained in absence of better methods to monitor the temperature of the contents of the delivery device. In light of these circumstances there is a need for constant monitoring of both internal temperatures close to the medicines or goods in transit and the ambient temperature the device is experiencing. [0005] Because of the need to have medicines both readily available and maintained at a certain temperature, insulated containers have been available for many years for transporting vaccines and other similar medications in transit to the field site of use. However, most such devices are passive insulated containers filled with blocks of ice or frozen gel packs which rely on a separate freezer system for refreezing. Transportation of such devices with available contents can also be subject to external factors such as weather, ambient temperature, and other unforeseen circumstances during delivery. For example, unforeseen delays during a delivery may jeopardize the cooling capacity of the materials within the system.

[0006] Therefore, there remains a need for a self-contained, compact and portable cooling storage system for transporting items that require temperature control. There also remains a need for a system that can predict the battery lifetime of the system based on external factors during transportation of the materials.

SUMMARY

[0007] A refrigeration unit system is disclosed and can comprise a system housing having a front panel, a back panel, two side panels, a bottom panel, a bezel having an air exhaust. The system can further comprise a plurality of air intake slots and a carrying handle above the air exhaust. The system can further comprise an assembly having a cold chamber central to the assembly. The assembly can comprise a thermoelectric module affixed to the chamber in direct contact. The thermoelectric module can be configured for conduction of a heat away from the cold chamber. The cold chamber can comprise a shelf removable from the cold chamber.

[0008] The system can further comprise an insulation surrounding the cold chamber and arrayed so as to create a sealed and insulated environment. The system can further comprise a heat flow system comprising a heat exchanger, a cold plate, and a heat conducting plate. The heat exchanger can comprise fins to cool the refrigeration unit system. The heat conducting plate and the heat exchanger can be connected via heat pipes configured to conduct the heat away from the heat conducting plate to the heat exchanger. The heat exchanger can release air through the air exhaust. The thermoelectric module can be in mechanical contact with the heat conducting plate and the cold plate. The thermoelectric module can be mounted to the cold plate by a mounting frame. The thermoelectric module can be compressed against the cold plate. The heat conducting plate can be between the cold plate and the heat exchanger. The cold plate can be between the cold chamber and the thermoelectric module.

[0009] The system can further comprise a fan. The heat exchanger can be coupled to the fan. The fan can be configured to circulate cooling air over the fins of the heat exchanger. The system can further comprise thermal probes attached to the cold chamber and the heat exchanger. The thermal probes can be exposed to an ambient environment having an ambient temperature. The probes can be configured to determine a temperature in the middle of the cold chamber and monitor system temperature states of the system.

[0010] The system can further comprise a user interface screen located on the housing. A printed circuit board can be located behind the user interface screen. The system can further comprise a system microprocessor within the printed circuit board. The system microprocessor can monitor the system temperature states and performs a cooling algorithm based on the system temperature states when the refrigeration unit system is powered by a rechargeable battery in the system housing. The system microprocessor can set a target temperature near an upper end of a selected temperature range when a mains power is not connected to a mains power connector. The system microprocessor can set the target temperature near a lower end of the selected temperature range when the mains power is connected to the mains power connector.

[0011] The system can further comprise a computer in satellite data communication with the refrigeration unit. The computer can receive data of a location of the refrigeration unit, a battery charge level of the refrigeration unit, the selected temperature range, an internal temperature inside of the refrigerator unit, and the ambient temperature outside of the refrigerator unit. The system microprocessor can calculate a remaining time of operable life of the refrigerator unit using the data of the internal temperature inside of the refrigeration unit and the ambient temperature outside of the refrigerator unit. The operable life can comprise an amount of time the unit has left wherein the cold chamber will remain below the upper end of the selected temperature range. The refrigeration unit system can be configured so the system microprocessor adjusts settings of the refrigerator unit based on the operable life.

[0012] The cold chamber can comprise a metal. The metal can comprise aluminum sheet metal. The insulation can be comprised of polyurethane foam. The algorithm can run the thermoelectric module by pulsing the refrigeration unit system between on and off states. The system microprocessor can sense a connection of the system to AC mains power and simultaneously charge the battery while running the thermoelectric module in order to cool the cold chamber.

[0013] A method for using a refrigeration unit system is also disclosed. The method can comprise a step of placing contents into a cold chamber within an assembly. The assembly can comprise a plurality of walls and a plurality of sensors on a perimeter of the assembly. The method can further comprise controlling heat flowing into and within the cold chamber using a thermoelectric module coupled to the cold chamber. The method can further comprise maintaining continuous operation of the thermoelectric module. The method can further comprise sensing temperature states at the perimeter of the assembly and at the plurality of sensors. The method can further comprise determining with a microprocessor an estimated temperature at a center of the cold chamber using the temperature states at the perimeter of the assembly and the ambient temperature.

[0014] The method can further comprise powering the system with one or more batteries coupled to the assembly. The method can further comprise predicting a battery lifetime of the one or more batteries based on at least one parameter selected from the group of: ambient temperature, battery capacity, the number of batteries, and a state of charge for each of the one or more batteries. The method can further comprise planning a route for the assembly to reach a desired location while maintaining the one or more of contents within a desired temperature range. Planning the route can be based on weather or ambient temperature in real time.

[0015] The method can further comprise swapping power between the one or more batteries. The method can further comprise charging the system by sending power directly to the assembly when the one or more batteries are fully charged. Maintaining continuous operation of the thermoelectric module can comprise applying constant voltage to the thermoelectric module.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figures la through le are isometric perspective, front, right, rear, and top views, respectively, of a variation of the portable refrigerator unit in open (Figure la) and closed configurations (Figures lb through Id).

[0017] Figure la’ is a photographic image of a variation of the refrigerator.

[0018] Figure la” is a close-up of a photographic image of the internal space and surrounding components of a variation of the refrigerator in a configuration with the door open. [0019] Figure 2 is an isometric view with the top bezel and photovoltaic panel shown in a removed configuration.

[0020] Figure 3 a shows the insulated container without the insulating panels surrounding it, including the power pack which contains the rechargeable battery, the charge controller, and other power electronics.

[0021] Figure 3b shows the vacuum insulated panel assembly which surrounds the insulated container.

[0022] Figure 3c shows the attachment of the insulated door to the insulated container.

[0023] Figures 3d and 3e illustrate views of various parts of the refrigerator unit that remove heat from the system.

[0024] Figure 4a is an exploded view of a variation of the portable refrigerator unit having the assembly of the heat exchanger on the insulated container with the TE module in mechanical contact with both the surface of the insulated container and the heat exchanger assembly.

[0025] Figure 4b shows the detail of the heat exchanger assembly including the cold plate, the thermoelectric module, the module mounting frame, the module mounting posts, the module mounting brackets, the hot plate, the heat pipes, the heat exchanger and the exhaust fan. At the bottom of the assembly is shown the battery pack and charging elements of the assembly.

[0026] Figures 5a, 5b are cropped front and isometric views, respectively, of a variation of the refrigerator without the front door for illustrative purposes.

[0027] Figure 5c is a cropped isometric view of the refrigerator of Figures 5a and 5b without the enclosure shown for illustrative purposes.

[0028] Figures 5d and 5e are cropped isometric and front section views, respectively, of the refrigerator of Figures 5a and 5b.

[0029] Figures 6a illustrates a variation of the refrigerator unit having a back door for access to swappable batteries.

[0030] Figure 6b illustrates a variation of a method for removing a battery from the refrigerator unit of Figure 6a.

[0031] Figure 6c illustrates the variation of the refrigerator unit of Figure 6a with a battery removed.

[0032] Figure 6d illustrates a front perspective view of the refrigerator unit of Figure 6a. [0033] Figure 6e illustrates a perspective view of a variation of a battery of the refrigerator unit. [0034] Figure 6f illustrates an exploded view of a variation of a battery.

[0035] Figures 7a to 7c illustrate various views of a variation of the refrigerator unit having two shelves within the container.

[0036] Figure 7d is a schematic cross-section view of a variation of the refrigerator showing heat flow from an ambient environment to a center of the chamber.

[0037] Figure 7e is a graph illustrating an analysis for determining an estimated temperature at various points from the outside of the chamber to the center of the chamber. [0038] Figure 8 is a graph illustrating the temperature measured by the temperature sensor during changings in ambient temperature.

[0039] Figures 9a illustrates an electrical schematic representative of the various electrical components in the system, their relation to each other, the connections between the components, and their relative functional roles in the system.

[0040] Figure 9b illustrates a schematic of a variation of a power source subsystem for the unit.

[0041] Figure 9c illustrates a schematic of yet another variation of a power source subsystem for the unit.

[0042] Figure 10 is a schematic network diagram of a variation of the refrigeration unit management system overlaid on a map illustrating approximate exemplary geographical locations of the components of the system.

[0043] Figure 11 is a schematic drawing of a variation of a networked refrigeration unit management system.

[0044] Figure 12 illustrates a variation of a summary display for the unit interface screen, remote computer, runner computer, or variations thereof.

[0045] Figures 13a through 13c illustrate variations of a map display for the unit interface screen, remote computer, runner computer, or variations thereof.

[0046] Figures 14a through 14c illustrate variations of temperature control displays for the unit interface screen, remote computer, runner computer, or variations thereof.

[0047] Figures 15a and 15b illustrate perspective views of the refrigerator unit.

[0048] Figure 15c illustrates a back view of the refrigerator unit.

[0049] Figure 15d illustrates a back view of the refrigerator unit.

[0050] Figure 15e illustrates a top view of the refrigerator unit.

[0051] Figures 15f and 15g illustrate side views of the refrigerator unit.

[0052] Figures 16a to 16d illustrates perspective and exploded views of various parts of the refrigerator unit that remove heat from the system. DETAILED DESCRIPTION

[0053] Figures la, la’ and la” show a portable refrigeration assembly or unit 10 (also referred to herein as a refrigerator) of approximately 30 inches in height, 10 inches in width, and 14 inches in depth, or less in dimensions. The portable refrigeration unit 10 can contain an insulated container 12 internal to the assembly that can have an approximate 4- 12 liter volume, for example an 8 liter volume, cold chamber or internal space. The insulated container 12 can be held within an enclosure assembly and has an insulated door 14 to allow access to the contents of the insulated container 12. The insulated door 14 can rotate about door hinges 18 at both top and bottom of the door. The insulated door 14 when pressed against the enclosure assembly can create a seal 16 that keeps the cold internal temperature stable compared to the higher outside ambient temperature of the air. The refrigerator unit 10 can have a detachable photovoltaic panel assembly 26 comprised of photovoltaic cells 24. This photovoltaic panel assembly 26 can be used in the generation of electricity from incident sunlight falling on the photovoltaic cells 24. The photovoltaic panel assembly 26 can be retained on the side of the portable refrigerator 10 during transport through the use of panel mounting tabs 28 that capture the top and bottom edge of the photovoltaic panel 26. The unit can have an AC outlet and/or plug and cord 32, for example for unit operation and on-grid charging. A bezel 22 can be located on top of the assembly and can allow for the graphical user interface screen 20 to be placed and accessed.

[0054] As shown in Figure la’, the unit 10 can have a touch screen user interface screen 20. The unit 10 can have intake vents, such as a cooling intake 30. The internal space 74 of chamber can have shelves 72, as shown in Figures 5a through 5e, and/or custom sections. The unit can have a carrying handle 34 (obscured by the case in Figure la’) that can be foldable to lay flush against the top surface of the unit when the handle is not in use. The case of the unit 10 can have a photovoltaic panel assembly 26 or solar panel, for example hingedly attached to the remainder of the case so the solar panel can be rotated upward to be more directly facing the sun when a stronger charge is desired.

[0055] The unit can have an electrical power plug 32 (e.g., an AC plug for attaching to an AC main power source). The plug 32 can be on an extendable power cord and can retract and be obstructed by the solar panel when not extended.

[0056] Figure la” illustrates that the insulated door 14 of the unit can rotate open, accessing the insulated container 12 or internal space 74 of the unit 10. [0057] Figure lb shows the front of the portable refrigeration unit 10 with the air intake 38 or cooling intake 30 slots for which the heat exchanger can exhaust circuit visible near the top of the system. The system shown in Figure lb can have the insulated door 14 closed and the door latches 36 shown in the locked position, thus holding the door closed under compression for transport.

[0058] Figure 1c shows the right side of the enclosure for the portable refrigeration unit 10 where the side material of the enclosure 40 can be made from sheet metal. This material can be aluminum, steel or another lightweight alloy suitable for durable, exterior use devices.

[0059] Figure Id shows the back of the portable refrigeration unit 10 with the air intake slots 38 disposed near the top of the assembly. On the back panel of the unit can also be found the AC power inlet 42 for connection of a power cord. Next to the inlet 42 for the power cord can be a fuse holder and a power switch for safety and operation of the unit during energizing.

[0060] Figure le shows the top of the portable refrigeration unit 10 which has a ventilated air exhaust 44 in the top of the bezel 22. Alternatively, the air exhaust 44 can be on the back of the refrigeration unit 10. This exhaust area allows for hot air to be released from the heat exchanger assembly 50 during operation and more specifically for the exhaust fan 54 to vent the hot system as it operates. The exhaust area can be on the back of the unit 10. Above the heat exhaust area is a carrying handle 34 integrated into the bezel 22 at the top of the unit. This handle 34 allows for the portable unit to be carried in a fashion similar to that of a suitcase. The portable refrigeration unit 10 can weigh about 22 kg, for example from about 6 kg to about 22 kilograms depending on component selection, size of battery and insulated container volume. The unit can be used in the field for the delivery of cool items.

[0061] Figure 2 shows the photovoltaic panel 26 unmounted from the side of the unit 10 assembly thus allowing for the panel to be placed at a distance from the unit to collect the sun’s rays and generate electricity to charge the on board battery system. The distance this panel can be separated from the unit is determined by the length of hook up cable used between the photovoltaic panel 26 and the unit. A typical hook up cable length can range from 5-15 meters, thus allowing for placement of the panel outside of a clinic area where the cables could be run through an open window to the portable refrigeration unit 10. The bezel 22 can also be unattached as it would need to be for initial assembly and possibly for servicing of the exhaust fan 54 or to allow access to the microcontroller printed circuit board housed behind the user interface screen. The bezel 22 would be removed to allow access to wiring, or to switch a sim card on the communications printed circuit board attached to the microcontroller PCB.

[0062] Figure 3a represents the internal elements of the portable refrigeration unit 10. The insulated container 12 is shown without the surrounding walls. The heat exchanger assembly 50 can be located on top of the insulated container assembly. Disposed below the insulated container 12 component of the assembly can be the power pack 46 assembly. The power pack 46 contains the rechargeable batteries which may be of a lithium-ion type (LiON) or a lithium iron (LiFE) material or of the more traditional lead acid variety. The batteries sit next to the charge controller and the system power supply that determines the proper charge levels for the batteries and converts incoming AC power to the appropriate DC power for use in the system.

[0063] When the refrigerator is powered by mains power, the internal battery can be charged at a high rate that can recharge the battery in approximately 4 hours. If the only external power available is solar power, the CPU can control the battery charge rate by reducing it from the rate during mains power connection to a level which the solar panel can support. The battery charge rate can depend on environmental charge efficiency factors. The environmental charge efficiency factors can include the orientation of the photovoltaic panel assembly 26 relative to the sun, the season, the time of day, the atmospheric transparency, and combinations thereof. The environmental charge efficiency factors can be detected by environmental charge efficiency factor sensors on, in, or away from but in data communication with the CPU. The environmental charge efficiency factor sensors can deliver environmental charge efficiency data corresponding to any or all of the respective environmental charge efficiency factors to the CPU. The CPU can measure part or all of the available environmental charge efficiency data by measuring input voltage from photovoltaic panel assembly 26. For example, the chamber temperature set-point can be set by the CPU as though the refrigerator is running on battery power. The power conditions can be checked by the CPU, for example at least once per second, and the internal settings can be adjusted accordingly. The mains power supply can be an on-board switching power supply usable from around 110V (60Hz) to around 240V (50Hz).

[0064] Figure 3b shows the vacuum insulated panel assembly 48 of individual panels, both of a flat nature and in a bent configuration. These panels can be made from expanded foam, metallized film and/or aluminum foil which has been bonded and then sealed under vacuum thus creating highly effective insulation board materials. This vacuum insulated panel assembly 48 can be used as a jacket for the insulated container 12 portion of the device and keeps the internal portion of the system very cold as required to maintain the appropriate level of cooling to the contents of the portable refrigeration unit 10.

[0065] Figure 3c shows the insulated door 14 separate from the portable refrigeration system and demonstrates how the door can be mounted on the hinges 18 and made to swing into place and close tight as is represented in the previous figures. The user interface screen 20 located in the bezel 22 part of the device can have both touch screen capabilities and soft-key functionality that allows for changing input screens depending on user intention and stage of use. Behind the user interface screen 20 can be a printed circuit board (PCB) containing the microcontroller for system level operation, monitoring, power adjustment and feedback in the form of temperature readings to the on board communication module that can execute tracking algorithms (including receiving satellite location data) for the unit and communication to the internet cloud.

[0066] The walls of the refrigeration unit 10 can be made of a hollow plastic (e.g., High Density Polyethylene (HDPE)) forming the insulated container 12. The walls of the refrigeration unit 10 can comprise an expanding foam material, for example, polyurethane foam. The polyurethane foam can fill the walls of the refrigeration unit, providing insulation for the insulated container 12.

[0067] Figures 3d and 3e respectively show an exploded view and a coupled view of various parts of the refrigerator unit that remove heat from the system. The heat exchanger 50 can be coupled to the TE module 68, which can be stacked on top of a heat spreader 69. A cold chamber assembly 71 can be placed below the heat exchanger 50, TE module 68, heat spreader 69,

[0068] Figure 4a shows the thermoelectric module 68 mounted to the external side of the insulated container 12. The top of the insulated container 12 can be composed of a metallic material such as aluminum to promote good conduction of the cooling effect of the thermoelectric module 68. This portion of the assembly is referred to as the cold plate 52 because it is on the side receiving cold from the thermoelectric module 68. Figure 4b shows the heat exchanger assembly 50 and its attendant parts. The thermoelectric module 68, or TE module, is put in contact with the cold plate 52 of the insulated container 12 through use of a module mounting frame 64, module mounting posts 66, and module mounting brackets 62 for use in compressing the TE module 68 firmly against the cold plate 52 on the top of the insulated container 12. This assembly of the TE module 68 is often performed with a thermal paste to better assist in the conduction of heat energy away from the cold plate 52 and to the side of the hot plate 58 which is disposed in contact with, and on top of, the TE module 68.

[0069] The TE module 68 can be continuously operated (i.e., never shut off). Voltage can be constantly applied to the thermoelectric module to maintain continuous operation of the thermoelectric module. A programmable power supply and/or a fixed power supply with a PWM (on/off) type of control can control the TE module 68. For example, the programmable power supply can have a speed of about 1000 Hz and can use a control loop software that can converge on a setting of the power supply that can provide just enough heat flow through the TE module 68 to equal and counteract the heat flowing into the internal space 74 through the insulation. The heat flow can depend on the ambient temperature and the set-point temperature of the chamber. A power setting can control the heat flow. In one example, the power can be set to about 12 watts when the ambient temperature is about 43°C and the internal space 74 is to be set at 2.5°C. In another example, the power can be set to 1 watt when the ambient temperature is about 20°C and the internal space 74 is to be set at 2.5°C. However, the power setting can be changed according to the geometry of a particular design, the ambient temperature and the set-point temperature of the chamber. Accordingly, the TE module 68 can balance cooling and battery life during use of the device.

[0070] The unit 10 can comprise a system microprocessor which can be configured to monitor the system temperature states and perform a cooling algorithm based on the system temperature states that controls the TE Module Power as described above. The microprocessor can set the temperature of the internal space 74 to be about 6.5 °C when the system is running on battery power, and lower, for example about 2.5 °C, when the system is running on mains power.

[0071] In this state, the voltage applied to the TE module 68 can be relatively constant and never turned off. The voltage applied can be dependent on both the ambient temperature and the set-point temperature of the chamber. For example, at room temperature and a setpoint temperature of 6.5°C, the voltage applied can be about 2 volts. At an ambient temperature of 43 °C and a set-point temperature of 2.5 °C, the voltage applied can be about 15 volts. The control loop can be a standard Proportional/Integral/Derivative (PID) algorithm. The constants for each of the terms can vary by the model used.

[0072] For example, the CPU can direct about 5% or about 10% of the standard voltage (or power level) to the TE module 68 until reverting to the standard voltage (or power level) when the temperature in the chamber is outside of about 0.3 °C or more narrowly within about 0.1 °C of the set-point temperature of the chamber.

[0073] Figure 4b also shows the top side of the TE module 68 in contact with the hot plate 58 that can be connected via heat pipes 60 of highly conductive material to be in contact with the heat exchanger 56 at the top of the system. This heat exchanger assembly 50 can be designed especially suited for conducting large amounts of heat away from a relatively small area in an efficient and solid state manner whereby there is no movement of the hot plate 58 or the heat pipes 60 during normal operation save the possible changing in size of the components due to rapid increases in temperature. The heat exchanger 56 at the top of the assembly can be run through by the heat pipes such that heat conducted away from the hot plate 58 is exhausted into the heat exchanger 56 which is in turn cooled by a top mounted exhaust fan 54 that sucks the heat out of the heat exchanger 56 and sends it away from the portable refrigeration unit 10.

[0074] Figures 5 a through 5e illustrate that the internal space 74 or chamber of the insulated container 12 can have one or more shelves 72. The shelves 72 can oriented parallel with respect to each other and horizontal. The shelves 72 can be slidably extended and removed from the internal space 74. The shelves 72 can be locked into place inside of the internal space 74.

[0075] The refrigerator unit 10 can have cold packs 70 attached to the outside surface of the insulated container 12. The cold packs 70 can each have a reservoir filled with 350 g of phase-change material (e.g., PCM-OM06P from RGEES, LLC of Arden, NC). The phase change material can change phase at 5.5 °C. The cold packs 70 can have high latent heat storage and can be safe to make contact with the temperature-sensitive load.

[0076] The cold packs 70 can be rectangular, and can be attached to the sides, top, bottom, back, or combinations thereof of the insulated container 12. The cold packs 70 can be attached to the insulated door 14. The cold packs 70 can be slidably removed from the refrigerator unit 10. For example, warmer cold packs can be swapped for colder cold packs.

[0077] Figures 6a through 6d illustrate that the refrigerator unit 10 can have a rear door 110 for access to swappable batteries 112 in the rear of the unit and a handle 116 for carrying the unit. The swappable batteries 112 configured to swap power between each other. The refrigerator unit 10 can comprise a handle 116 for ease of carrying the unit. [0078] The rear door 110 can be hingedly attached to the container, for example, to allow for a user to access the swappable batteries 112. The swappable batteries 112 can be removed from and/or replaced within the refrigerator unit 10. For example, the swappable batteries 112 can be removed or inserted through the rear door 110. To remove or replace a battery 112, a latching mechanism 114 can be undone to release the battery 112. The latching mechanism can secure the battery 112 in place during transportation of the unit 10. To release the latching mechanism, the user can twist the latch mechanism 114, allowing the battery 112 to be tilted out of the container 12, as seen in Fig. 6b. It should be appreciated that any suitable latching mechanism can be used for securing batteries 112. [0079] The swappable batteries can be smart batteries. The smart batteries can allow for selecting power from one of the batteries depending on a known charge state. The unit 10 can select one of two battery packs can be selected to draw power from, for example, depending on the power level of the batteries. Accordingly, selecting and switching which battery power comes from can extend the range that the refrigeration unit can travel. This range can be indefinite with multiple packs if one battery pack is being charged while another is being discharged. For example, at a high ambient temperature (e.g., 43 °C) each pack can last about 6 hours. With multiple battery packs, the range can be 6 times the number of packs. Power thresholds at which the batteries switch upon discharge can be modified depending on various factors, such as weather, potential distance to be travel, or other factors thereof. Alternatively, as seen in Fig. 6c, the refrigerator unit 10 can comprise of and run on a single battery 112.

[0080] The batteries can be Lithium-Ion batteries (LiOn) can allow for air transit when proper charging cycles and packaging methods are incorporated. LiOn battery packs can include an integrated battery management system (BMS) that outputs more accurate charge cycle information to the algorithm, while maintaining appropriate levels of power. The algorithm and battery system can have a charge life up to 24 hours. The batteries can charge via a standalone charging station. The batteries can each have a total capacity of 610 Wh. The BMS can keep track of current both into and out of the battery using a “Coulomb Counter”. Without this device, the state of charge of the pack can only be estimated to about +/-10% based on the pack voltage. The Coulomb Counter method can improve this estimate to about +/-1%.

[0081] Figure 6e illustrates a perspective view of a variation of a battery 112 of the refrigerator unit. As seen in Fig. 6e, the battery 112 can have a battery pack connector 118 to connect to the refrigeration unit 10. The battery 112 can also have a charge state button 120 and a charge state indicator 122 for reading the battery life. The charge state button 120 can query battery 112 as to its approximate remaining charge level. The charge state indicator 122 can activate lights to show the approximate charge state to a user. A battery connector seal 124 can be provided to couple the battery with the refrigeration unit 10. The battery 112 can be sized to fit within the insulated container 12. The battery 112 can have a shape such that latch mechanism 114 can easily secure the battery 112 when placed within the insulated container 12. In one variation, the battery 112 can have dimensions of 3.7” (94mm) x 10.34” (263mm) x 4.13” (105mm) and can sit in a compartment that measures -8.125” (207mm) x 12” (305mm) x 4.25” (108mm).

[0082] Figure 6f illustrates an exploded view of a variation of a battery 112. The battery 112 can have a top enclosure 126 and a bottom enclosure 134. The top enclosure 126 and the bottom enclosure 134 can have gaskets 130 coupled to the enclosures via screws 128. The battery pack connector 126 and the battery seal connector 124 can be coupled to the top enclosure 126. Foam paddings 132 can be placed adjacent to the gaskets 130 and can protect the components within and adjacent each enclosure.

[0083] An extrusion 136 can be provided around a perimeter of the battery 112. Extrusion 136 can protect battery cells and the BMS board 138, which can be positioned near the top enclosure 126. A foam padding 140 can also be provided around a perimeter of the battery 112, interior and adjacent to the extrusion 136.

[0084] Figures 7a and 7b show another variation of refrigeration unit 10 having two shelves 72 within the internal space. The shelves 72 can be accessed by opening insulated door 14 at a front of the unit 10. The unit 10 can have a rear door 110 and can open from its top. As seen in Figure 7c, a back panel of the internal space 74 can comprise two thermistors 75 attached to, integrated with, or on and/or in an inner surface or wall of the insulated container 12. In this configuration, the thermistors 75 can be placed approximately level with the platforms of shelves 72.

[0085] An estimated temperature at a center of the internal space 74 of the insulated container 12 can be determined via the thermistors 75. The thermistors 75 can be on a back side of the insulated container 12, on the sides of the insulated container 12, or in various combinations thereof. The plurality of sensors 75 can be configured to measure temperature states at the perimeter of the assembly. By determining an estimated temperature at a center of the insulated container 12, the device can compensate for thermistor errors due to thermistor location as measuring the temperature directly at the middle of insulated container 12 can be impractical for various reasons. Accordingly, the thermistors can provide an accurate estimate of the temperature of the contents placed within the center of the insulated container 12. A system microprocessor can then use the temperature states at the perimeter of the unit to determine an estimated temperature at the center of insulated container 12. The estimation can be used to keep vials within the insulated container 12 at a constant temperature, for example, between 2°C and 8°C. [0086] Figure 7d illustrates a cross-section view of an assembly showing heat flow through the assembly in a steady state condition. The heat flow can extend from outside of the container, through the insulation walls, and towards the center of the chamber. A plurality of temperature sensors or thermistors 75 can be attached to, integrated with, or on and/or in an inner surface or wall of the insulation. The insulation can reduce the heat flow from outside of the container to the center of the chamber. The contents to be delivered can be located in the chamber, for example in the center of the chamber.

[0087] The temperature sensors or thermistors 75 attached to the cold chamber as well as the ambient temperature can be used by the system microprocessor to determine the temperature in the middle of the cold chamber and perform a cooling algorithm based on the system temperature states.

[0088] Figure 7e illustrates a graph that shows estimated temperature that can be measured at various points from the outside to the center of the insulated container 12. Because the distances and insulation resistances remain relatively constant, measurements can compensate for the location of the thermistor along the perimeter of the cold chamber. Using a defined factor “K”, calculations of the virtual vial temperature can be completed with the following equation:

T _v = Tt - (K * (Ta - Tt)) where T _v represents the virtual vial temperature, T _a represents the measured ambient temperature, and Tt represents the top chamber thermistor temperature. In one example, based on measurements in the thermal test chamber, a K factor of 0.26 can result in less than 0.2°C error at ambient temperatures of 25°C and 43°C. This analysis can be used when the insulated container 12 is in a steady state where the ambient temperature is not changing. This equation for Tv can be used to estimate the temperature a vial would be experiencing at the center of the chamber. This can allow for the temperature sensors or thermistors 75 to be placed away from the area that will be occupied by the refrigerator contents while maintaining an accurate temperature reading at the center of the chamber. [0089] The K factor can be individually calculated for each individual unit 10 using calibrated temperature sources. This allows for individual characteristics of each unit 10 to be used to determine an accurate temperature calculation. Individual characteristics can include differences from unit to unit in wall thickness of the plastic and in the polyurethane foam that are inherent within the manufacturing processes.

[0090] If there is a change in the ambient temperature, the effect on the top chamber thermistor can be delayed and the ambient temperature thermistor can react accordingly. To compensate for this effect, the term used as T _a in the above equation can be processed by a long-time constant filter.

[0091] Figure 8 illustrates a graph showing readings of the temperature sensor of the container 12 during stepped changes in ambient temperature over time. In this example, the ambient temperature (T _a ), shown by the “Ambient” line can be stepped from approximately 16.5 °C to 34°C. Then, the ambient temperature (T _a ) is reduced first to 25 °C and finally back to 16°C. The “Chamber” line shows the response of a thermocouple placed adjacent to the top chamber thermistor during the stepping of the ambient temperature. The “Simulation” line shows the response of a filter designed to imitate the physical results. A new value for Simulation can be calculated once per minute using the following formula:

Next Simulation = Last Simulation + (R * (Ambient - Last Simulation)) where R is a constant chosen to make the two curves match as closely as possible, which can be set to 0.003 for the example in Figure 6c.

[0092] The “Difference” line is the difference between the “Celsius” line and the “Simulation” line. The scale for the “Difference” line is located on the right side of Figure 8. The saw-tooth shape of this line can be due to the 0.5°C resolution of the original temperature measurements. In one example, an error in the filter of 2°C multiplied by the correction factor of 0.26 can result in a net error of about 0.52°C.

[0093] Figure 9a shows the electronic components of the system and their function in a schematic layout representative of their connections and relative functionalities. The block diagram shows the AC mains inlet which can lead to the AC-DC power supply and converter. This component can provide DC power to the system through a relay. The AC mains can also be connected to a battery er that charges the battery pack. The battery can then in turn provide DC power to the system through the relay. When the photovoltaic solar panel is connected and generating electricity, it can feed DC power into the solar charge controller which in turn can charge the battery. The battery then can run DC power to the system through the relay the same as when charged from AC mains.

[0094] The microcontroller central processing unit (CPU) can control the logic of the system and distributes the DC power to the system level components including the thermoelectric module 68, the resistance heater, and the exhaust fan 54. The microcontroller can also send small DC voltages to the thermistors which read the temperature of the interior of the insulated container 12 and the ambient external temperature. The microcontroller can also be connected to the communications module which includes a GPS receiver to determine global position via satellite and the GPRS/GSM modem that provides connectivity to the internet and cloud based servers that support the data acquisition aspects of the devices functionality.

[0095] The electronic system design for the portable refrigeration unit 10 can be based on a PIC24EP processor which can have a 320 x 240 TFT color display with touch panel. This can provide the user interface for the unit and can also monitor and controls the heating or cooling of the chilled chamber. The presence of the TE module 68 can allow for cooling of the insulated container 12. The likely addition of a small resistance heater in the insulated container 12 also means that the system can be used to heat the contents enough to avoid any risk of freezing the contents.

[0096] Power MOSFETS connected to IO pins on the processor provide control for the thermoelectric module 68, a resistive heater, and the fan.

[0097] The temperature of the chilled chamber and the TE module heat sink can be monitored with NTC thermistors connected to analog inputs on the processor. The resulting voltages can be converted with the on-board Analog to Digital Converter (ADC) and the actual temperatures are calculated using the standard Steinhart-Hart algorithm and displayed.

[0098] The temperatures can be sampled routinely and as an example at the rate of once per second and averaged by the firmware over a time range which could be 8 seconds. [0099] The firmware can be based on a periodic interrupt in the range of 1-100 times per second. In the case where it is 20 times per second as an example, this divides each second into 20 time slots. The various processor tasks can be allocated to different time slots to even out the load on the processor and to allow for better power management. On each interrupt, the touch panel can be sampled to determine if the user has made any inputs to the system.

[0100] Temperature control can be done with a simple on/off thermostat type of algorithm with a hysteresis of 0.1 °C. The user can have control of the set-point via a menu selection. The default can be at any temperature, for example, 5 °C. When the temperature is above the set-point minus the hysteresis, the TE module 68 is turned on. When the temperature drops below that point, the TE module 68 can be turned off. When the temperature rises above the set-point plus the hysteresis, the TE module 68 can be turned on again. This cycle can take from 30 seconds to 10 minutes and can keep the chamber temperature within +0.3°C and - 0.1 °C of the set-point as an example.

[0101] The TE module heat exchanger 56 temperature can also be controlled via the fan 54. If the heat exchanger 56 temperature rises above a set maximum, 40°C for example, the fan 54 can be turned on until the temperature drops to a safer level, perhaps below 35°C. This cycle can take a period of time from 10 seconds to several minutes, depending on ambient temperature.

[0102] The CPU can have features to support a GSM (cell-phone type) modem and a GPS receiver. The combination of these two interfaces can allow the portable refrigeration system to determine its location via the GPS receiver and then use the GSM phone interface to report the position and the status of the system to a server. This can allow for the remote management of any number of portable refrigeration systems in the field via the internet and cloud connected computer servers.

[0103] The refrigerator can keep the inside of the chamber below 10°C without going below 0°C, or another desired temperature target or range. The user can select a desired temperature range of approximately 6 °C (2 °C to 8 °C, for example), for example. The temperature measurement by a thermostat in the refrigerator can have a tolerance of about +/- 1°C.

[0104] The CPU can control the set-point of the temperature. The CPU can change the set-point of the temperature in the chamber depending on the power source or sources for the refrigerator and the desired temperature range. For example, if the refrigerator is running on mains power, the CPU can set the chamber temperature set-point at a temperature near the lower end (e.g., at 25% from the bottom of the range) or at the bottom of the selected temperature range. The chamber contents can then be chilled as much as possible so that when mains power is disconnected, the contents of the refrigerator have to warm up farther to exit the top of the desired range. This can result in a longer total run time.

[0105] If the refrigerator is running on battery power, the CPU can set the chamber temperature set-point to a temperature near the upper end of the selected temperature range (e.g., 75% from the bottom of the range). Battery power usage can be proportional to the difference between the internal and external temperature of the device, so allowing the internal temperature to rise can reduce the power drawn from the battery, extending the battery life. [0106] Figure 9b provides a schematic of a power source subsystem for the unit. The power source subsystem can be controlled by and send and receive data to and from a power source algorithm or scheme. The power source algorithm can be executed by the CPU. The power source algorithm can send real time reporting data to a display and/or remote devices regarding the remaining device battery life based on factors such as external ambient temperature, travel speed, location, number of door openings for the refrigerated compartment, or combinations thereof. The reporting data can be delivered immediately (i.e., on a display) and/or stored in a cloud. The system can use the battery as the primary source of power regardless of whether or not the unit is plugged into mains power. While the refrigeration unit 10 is plugged into mains power, it can draw power from the battery as it is charging.

[0107] Figure 9c shows a schematic of a power source subsystem for providing power to the unit and charging the components. The power source subsystem can select the power source dynamically based on stability. The power source algorithm can prioritize mains power to the refrigeration unit, followed by a DC power connection, followed by the battery or batteries. The power source algorithm can control the power source subsystem to use any available stable power source to concurrently charge the battery.

[0108] The power source algorithm can charge the battery that is closer to full while about 50% of mains power goes directly to the cooler bypassing both batteries. When the first battery is fully charged, the second battery can begin charging. When both batteries are fully charged, the charger can send all power directly to the cooler, bypassing the batteries. The power source algorithm can cool the cooler to the lower end of the acceptable temperature range to for the purpose of efficiency and to generate less overall heat.

[0109] Figure 10 illustrates that a refrigeration unit management system 76 can have the portable refrigeration unit 10, a remote computer 80, a runner computer 86, or combinations thereof. The remote computer and/or runner computer can each be one or more servers, desktop or laptop computers, mobile devices such as smartphones, tablets, PDAs, barcode scanners, or combinations thereof.

[0110] The portable refrigeration unit 10 can be in data communication with the remote computer over a remote-to-refrigerator connection 78. The runner computer 86 can be carried by a runner 90 or in a vehicle 88 carrying the portable refrigeration unit 10. The runner computer 86 can be in data communication with the remote computer 80 over a remote-to-runner connection 82. The portable refrigeration unit 10 can be in data communication with the runner computer 86 over a runner-to-refrigerator connection 84. Any of the connections can be through local area networks, wide area networks, wifi, Bluetooth, cell-phone type connections (e.g., GSM), infrared, optical (e.g., bar code scanning), or combinations thereof.

[0111] The remote computer 80 and/or runner computer 86 can receive and/or request data from the portable refrigeration unit 10 including the current and/or historical temperatures of the internal space of the unit and/or the ambient temperature outside of the unit (e.g., the unit can have digital thermometers inside and/or outside of the unit communicating with the CPU in the unit that can send out the temperatures to the remote and/or runner computers), the location of the unit, the items and their sizes stored in the unit (e.g., this can be entered manually into the unit’s memory and/or determined by an optical scanner inside of the internal space, scanning the internal space and using image recognition software, and/or merely sending the image itself as a visual log of the contents of the internal space), or combinations thereof. The remote computer 80 can have features such as GPS locatability and tracking, cellular connectivity, real time temperature feedback and run reporting, and on-board temperature monitoring.

[0112] The remote computer 80 and/or runner computer 86 can send data to the refrigeration unit 10 to adjust the unit settings (e.g., to extend battery life by increasing the temperature inside of the internal space, and/or reducing the duty cycling frequency of the unit).

[0113] The remote computer 80 and/or runner computer 86 can send a message to the runner computer 86 to ask the runner to stop delivery to plug in the unit to a power source or expose the solar panels to the sun or another light source, for example, when the remaining power in the batteries is below a level needed to reach the expected destination based on the current power load, speed of travel of the unit (based on the GPS readings), and length of travel remaining to destination, and also to alert the runner computer if there is a malfunction with the unit (e.g., from an unexpectedly high or low internal space temperature).

[0114] Figure 11 illustrates that the portable refrigerator unit 10 can be in a networked refrigeration system. The system can have nodes such as remote nodes, such as a server (e.g., a cloud server), supply manager terminal 92, healthcare technician terminal 100, and the local nodes such as the refrigerator unit 10, or combinations thereof. The nodes can all be in data communication with each other directly or indirectly, for example over the internet through the cloud server 94. The terminals can be desktop computers, laptop computers, handheld devices (e.g., tablets, smartphones), or combinations thereof.

[0115] The refrigerator unit 10 can communicate (e.g., via satellite and/or the GPRS/GSM modem, and/or a direct, wired Ethernet connection) with the cloud server 94. The unit can upload unit upload data to the cloud server 94. The unit upload data 98 can include, for example, location data including the present location and previous locations or path, battery charge level, internal temperature, external temperature, desired route, serial information to identify the unit and/or the driver/courier, manually entered notes (e.g., information entered by the driver regarding local environmental conditions), desired/preset internal temperature maximum, minimum, and/or temperature range, or combinations thereof.

[0116] An algorithm executing on a processor of the unit and/or cloud server, and/or another node in the system, can calculate the remaining distance range of the unit based on the location, desired route, battery charge, internal temperature, external temperature, and desired internal temperature maximum, minimum, and/or temperature range, or combinations thereof. This calculation can also be performed by the algorithm on the unit itself. The algorithm will calculate the estimated time the remaining battery charge can keep the internal temperature of the unit within the desired temperature range (e.g., including below the maximum temperature or above the minimum temperature), and then can estimate a distance range for the unit based on the projected speed of the unit. The cloud server 94 can download unit download data 96 to the unit including the distance range, and whether or not the unit is expected to arrive at a desired target location or endpoint before the internal temperature of the unit is no longer within the desired range, maximum, or minimum.

[0117] A battery lifetime algorithm can predict the battery lifetime. The battery lifetime algorithm can be run by a microprocessor (e.g., the CPU). The battery lifetime algorithm can first estimate the current battery charge in Amp-hours based on the known battery capacity, the number of batteries, and the state of charge (in percent) for each battery. Then the algorithm can calculate the duration, or cooling time, to bring the chamber down to a setpoint from the current temperature using a first testing factor derived from testing of the system. The thermoelectric module can be driven at full or standard power during the cooling time. The cooling time multiplied by the required power is subtracted from the current battery charge. [0118] The battery lifetime algorithm can then calculate a hold bum rate based on the ambient temperature and a second testing factor also derived from testing of the system. By dividing the charge remaining after reaching the setpoint by the hold bum rate, the CPU can be determined how long the battery will last in steady state (holding time). Finally, to calculate the estimated battery life, the cooling time and the holding time can be added together.

[0119] A routing algorithm can be configured to plan a route for the assembly to reach a desired location while maintaining the one or more contents within a desired temperature range. The routing algorithm can also be configured to plan the route based on weather or ambient temperature in real time.

[0120] The cloud server 94 (or the other nodes) can distribute any of the data disclosed herein to any of the nodes through a web interface, via e-mail, via text or SMS message (as shown for the healthcare technician interface), via automated voice messages as attachments with the aforementioned methods or via voice lines, or combinations thereof. [0121] Figures 12, 13a through 13c, and 14a through 14c illustrate that the user interface screen 20, remote computer 80, mnner computer 86, or combinations thereof, can display information provided by the unit and/or calculated by any of the nodes. The user interface screen 20 can be accessed and viewed on the unit and/or on any of the nodes.

[0122] Figure 12 illustrates that the display can be or have a summary display, screen or page. The summary page can show of the internal unit temperature with respect to time. The summary page can show the expected remaining operable time of the batteries. The operable time can be the remaining time for which the batteries can power the unit to keep the internal space below a desired temperature based on the remaining charge of the batteries. The summary page can show an expected time remaining to the delivery destination 106 for the unit.

[0123] Figure 13a illustrates that the display can be or have a map display 102, screen or page. The map display 102 can illustrate a map showing the current location 104 of the unit, the path including the starting location of the unit, the desired destinations 106 for the unit, the estimated allowable range for the unit, and a projected path to a desired destination 106 (e.g., a desired destination within the allowable estimated unit range). The allowable range can be the distance that the system calculates that the unit can travel based on the battery charge, desired internal temperature, external temperature, projected speed, and combinations thereof. [0124] Figure 13b illustrates that the map display 102 can display various estimated allowable ranges based on different levels of battery charges. For example, a first allowable range 108a can be shown if the battery has five hours of charge remaining based on the other data available. A second allowable range 108b can be shown if the battery has eight hours of charge remaining based on the other data available. A third allowable range 108c can be shown if the battery has twelve hours of charge remaining based on the other data available. The projected ranges can inform the runner or other users on the possible desire for additional charging of the battery to extend the range to a particular desired destination.

[0125] Figures 13a and 13b illustrate that the allowable range can be estimated as circles defining constant radii away from the current location of the unit. Figure 13c illustrates that the system can calculate the allowable ranges 108a-c based on expected speed and distance along particular routes, rather than as a constant radius. The system can calculate which desired destinations 106 are within the allowable range (e.g., with check marks), and which desired destinations are not within the allowable range (e.g., with crosses or “X”s) based on the current battery charge and other data.

[0126] Figure 14a illustrates that the display can be or have a first temperature control display, screen or page. The first temperature control page can show the current internal (inside of the internal space) and/or ambient temperature (around the outside) of the unit, the desired temperature range of the internal space, the strength of the network communication connection, the percent of battery charge remaining, or combinations thereof. The first temperature control page can have a button (e.g., “SETTINGS”) to advance to the second temperature control page.

[0127] Figure 14b illustrates that the display can be or have a second temperature control display, screen or page. The second temperature control page can show the hours of operation of the unit thus far in the trip (e.g., “HRS OPS”) which can be manually or automatically reset before each trip begins, the currently set temperature range, controls for adjusting the temperature range (e.g., “+” and for increasing and decreasing, respectively, the temperature by a single degree), the newly set temperature range, the strength of the network communication connection, the percent of battery charge remaining, or combinations thereof. In the second temperate control page, the user can modify the desired temperature range for the internal space. The second temperature control page can have a button (e.g., “CONTINUE”) to advance to the third temperature control page. [0128] Figure 14c illustrates that the display can be or have a third temperature control display, screen or page. The third temperature control page can show the maximum and minimum temperatures experienced by the internal space since the beginning of the trip for the unit (e.g., the maximum and minimum trip temperatures can be manually or automatically reset before departing for each trip), a hold over time (i.e., the expected remaining operable time of the batteries to keep the internal space within the desired temperature range), the strength of the network communication connection, the percent of battery charge remaining, or combinations thereof.

[0129] The display can cycle automatically and/or manually through the first, second, and third temperature control pages.

[0130] Figures 15a to 15g illustrate another variation of the unit 10 with the air exhaust 44 located on the back side of the unit 10, as seen in Fig. 15c.

[0131] Figures 16a to 16d illustrate coupled views and an exploded view of various parts of the refrigerator unit that remove heat from the system. In particular, insulator 142 can be provided to surround parts of the system in order to transfer or remove heat.

[0132] The variations above are for illustrative purposes and it will be apparent to those skilled in this art that various equivalent modifications or changes according to the idea of and without departing from the disclosing and teaching herein shall also fall within technical scope of the appended claims. For example, any of the materials disclosed herein can be used to make any of the elements.

[0133] Systems and methods that have elements that can be used in combination with the disclosure herein include those taught in U.S. Patent Nos. 6,929,061, 7,728,711, 8,026,792, 8,280,550, 9,182,155, U.S. Patent Pub. Nos. 2012/0036869, 2015/0143823, 2019/0003757 (U.S. Application No. 15/573,781, filed May 14, 2016), and U.S. Provisional Application Nos. 62/161,173, filed May 13, 2015, and 62/253,272, filed November 10, 2015, all of which are incorporated by reference herein in their entireties.

[0134] Any elements described herein as singular can be pluralized (i.e., anything described as “one” can be more than one), and plural elements can be used individually. Any species element of a genus element can have the characteristics or elements of any other species element of that genus. The term “comprising” is not meant to be limiting. The above-described configurations, elements or complete assemblies and methods and their elements, and variations of aspects thereof can be combined and modified with each other in any combination.