INCLUDING THE SAME

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of United States Provisional Patent Application No. 63/136,535, filed January 12, 2021 , entitled “ELECTRODE FOR LEAD ACID STORAGE BATTERY”, the entire content of which is hereby incorporated by reference herein in its entirety.

FIELD

[0002] The disclosure relates to the field of batteries (e.g., lead-acid storage batteries including batteries for vehicle starting, lighting, and ignition applications; marine batteries; commercial batteries; industrial batteries; batteries for use w'ith electric vehicles, hybrid-electric vehicles, micro-hybrid vehicles, etc.).

BACKGROUND

[0003] Lead-acid batteries are widely known. A typical lead-acid battery may include several electrodes substantially submerged in an electrolyte (e.g., an aqueous sulfuric acid). The electrodes include anodes, which may be made of an active material such as lead or a lead alloy, and cathodes, which may be made of an active material such as lead dioxide or another lead alloy. The electrodes chemically interact with the electrolyte to convert chemical energy into electrical energy and in some cases convert electrical energy into chemical energy. The electrodes typically include collection lugs.

[0004] Often, the electrodes are manufactured as pasted grids. The pattern of the grid can affect the current density or current flow on the electrode. Such electrodes may include a lead or lead alloy grid and a paste that includes red lead, dilute sulfuric acid, and/or other additives, such as, for example, expanders. Paste may be provided on the grids and/or pressed into apertures defined by the grids and may then be dried or allowed to dry. [0005] Traditional batteries may also include separators provided between the electrodes. The separators may be made from, for example, wood, rubber, glass fiber, cellulose, sintered PVC/poly ethylene, and/or any other known or later-developed insulating or nonelectrically- conductive material.

[0006] It has been found that not fully utilizing available material of the electrodes causes uneven current density and reduces cycling performance of the electrodes (and the lead-acid battery). Creating an uneven current density between two or more electrodes of a lead-acid battery may contribute to acid stratification and/or sulfation within the lead-acid battery, which further exacerbates the issue. As a result, the battery may be maintained at a partial charge for an extended period of time, thereby reducing the performance of the battery and may eventually lead to a premature failure of the battery.

SUMMARY

[0007] Accordingly, an electrode for a lead-acid battery is provided. The electrode has a grid with a pattern that is configured to provide substantially uniform current density throughout the electrode.

[0008] In embodiments, the pattern is substantially symmetrical about a central axis of the grid. In further embodiments, the pattern includes a primary current path member extending from a collector lug of the grid. The collector lug is offset from the central axis. The primary current path member includes increased material from the general pattern of the grid, is continuous from the collector lug to the central axis, and is substantially symmetrical about the central axis.

[0009] Inclusion of the primary’ current path member helps to force current down into deeper parts of the electrode, which utilizes more material of the electrode, thereby improving cycle life of the electrode. Further, forcing the current deeper into the electrode and utilizing more material promotes a more uniform current density. Inclusion of a substantially symmetrical pattern helps lower resistance of the electrodes and helps reinforce current flow post-to-post among positive and negative electrodes. [0010] A lead-acid batery is further provided. The lead-acid battery includes a plurality of electrodes. Each electrode has a grid with a pattern that is arranged to provide substantially uniform current density throughout the electrodes.

[0011] A method for manufacturing a battery electrode is also provided. The method includes, in embodiments, stamping a grid pattern so as to provide uniform current density,

[0012] These and other features and advantages of various embodiments of systems and methods according to this invention are described in, or are apparent from, the following detailed description of various exemplary embodiments of various devices, structures, and/or methods according to this invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Various examples of embodiments of the systems, devices, and methods according to this invention will be described in detail with reference to the following figures.

[0014] FIG. 1 is an isometric view of a vehicle including a battery according to one or more examples of embodiments.

[0015] FIG. 2 is an isometric cut-away, progressive, partially exploded view of a battery that may be used with the vehicle of FIG. 1.

[0016] FIG. 3 is a front plan partially cut-away view of a batery plate or electrode (e.g., a positive battery plate) comprising a stamped grid and active material that may be used with the battery of FIG. 2.

[0017] FIG. 4 is a front plan view of one example of a stamped grid (e.g., a positive grid) that may be used with the battery of FIG. 2.

[0018] FIG. 5 is an isometric cut-away view of a battery plate or electrode (e.g., negative battery plate) and separator that may be used with the batery of FIG. 2.

[0019] FIG. 6 is a schematic representation of the relative current density passing between two electrodes (e.g., an anode and a cathode) of a conventional battery. [0020] FIG. 7 is a schematic representation of the relative current flow passing between two electrodes (e.g., an anode and a cathode) of a battery’ with the improved grid pattern described herein according to one or more examples of constructions, an example of which is shown in FIG. 8.

[0021] FIG. 8A is a front plan view of an electrode having a first polarity, the electrode including a stamped grid pattern that reduces stratification of a lead-acid battery’, such as the battery of FIG. 2, and increase material usage of the electrode in accordance with an example construction described herein.

[0022] FIG. 8B is a front plan view of an electrode having a second polarity, the electrode including a stamped grid pattern that reduces stratification of a lead-acid battery, such as the battery' of FIG. 2, and increase material usage of the electrode in accordance with an example construction described herein.

[0023] FIG. 9A is a front plan view of an electrode having a first polarity, the electrode including a stamped grid pattern that reduces stratification of a lead-acid battery, such as the battery of FIG. 2, and increase material usage of the electrode in accordance with an example construction described herein.

[0024] FIG. 9B is a front plan view of an electrode having a second polarity, the electrode including a stamped grid pattern that reduces stratification of a lead-acid battery, such as the battery' of FIG. 2, and increase material usage of the electrode in accordance with an example construction described herein.

[0025] FIG. 10A is a front plan view of an electrode having a first polarity, the electrode including a stamped grid pattern that reduces stratification of a lead-acid battery, such as the battery of FIG. 2, and increase material usage of the electrode in accordance with an example construction described herein.

[0026] FIG. 10B is a front plan view of electrode having a second polarity, the electrode including a stamped grid pattern that reduces stratification of a lead-acid battery, such as the battery of FIG. 2, and increase material usage of the electrode in accordance with an example construction described herein. [0027] It should be understood that the drawings are not necessarily to scale. In certain instances, details that are not necessary to the understanding to the invention or render other details difficult to perceive may have been omitted. It should be understood, of course, that the invention is not necessarily limited to the apparatus or processes illustrated herein.

DETAILED DESCRIPTION

[0028] Referring to FIG. 1 , a vehicle 20 is shown that includes a battery 22 according to one or more examples of embodiments. The size, shape, configuration, and location of the battery 22 and the type of vehicle may vary according to various examples of embodiments. For example, while the vehicle 20 shown is an automobile, according to various examples of embodiments, the vehicle may comprise a wide variety of different types of vehicles, including, among others, motorcycles, buses, recreational vehicles, boats, and the like. The battery 22 may supply power for various vehicles, including, for example electric powered vehicles, hybrid electric vehicles, and gasoline powered vehicles.

[0029] According to one or more examples of embodiments, the vehicle 20 uses an internal combustion engine or a hybrid or other drive for locomotive purposes.

[0030] The battery 22 shown in FIG. 1 is configured to provide at least a portion of the power required to start or operate the vehicle 20 and/or various vehicle systems (e.g., starting, lighting and ignition systems). Further, it should be understood that the battery 22 may be utilized in a variety of applications not involving a vehicle, and all such applications are intended to be within the scope of the present disclosure.

[0031] Tire battery 22 shown in FIG. 1 may include any type of secondary' battery (e.g., rechargeable battery). According to one or more examples of embodiments, the battery includes a lead-acid storage battery. Various embodiments of lead-acid storage batteries may be either sealed (e.g., non-maintenance) or unsealed (e.g., wet). For ease of explanation, the lead-acid storage battery described herein is an unsealed lead-acid battery and periodically requires the addition of electrolyte and/or water to maintain a desired volume and/or concentration of either or both. [0032] A lead-acid storage battery 22 according to one or more examples of embodiments is illustrated in FIG. 2. FIG. 2 depicts a cutaway, progressive exploded, isometric view' of the lead- acid storage battery 22. The lead-acid storage battery 22 includes a plurality of electrochemical electrodes or plates 24, 26 and plate sets, generally designated 28 (e.g., lead-acid). Other configurations may be used in accordance with various other examples of embodiments. In various embodiments, the lead-acid storage battery 22 includes several cell elements 'which are provided in separate compartments of a container or housing containing electrolyte. The illustrations provided herein relate to automotive applications, wherein groups of 12-16 plates are used in each of six stacks for producing a standard automotive 12- volt batten'. It wall be obvious to those skilled in the art after reading this specification that the size and number of the indivi dual grids, the size and number of pl ates in any particular stack, and the number of stacks used to construct the battery may vary widely depending upon the desired end use.

[0033] In various embodiments, the battery housing 30 includes a box-like base or container and is made of a moldable resin. A plurality of plate blocks are connected in series according to the capacity of the lead storage battery and are accommodated in the battery container or housing together with the electrolyte, which is most commonly aqueous sulfuric acid.

[0034] In various embodiments, the battery 22 includes a compartment 30 having a front wall, end walls, a rear wall, and a bottom wall. In various embodiments, five cell partitions or dividers are provided between the end walls, resulting in the formation of six compartments, as typically would be present in a twelve-volt automotive battery. In various embodiments, a plate block is located in each compartment, each plate block including one or more positive and negative plates 24, 26, each having at least one lug 60, 68, and optionally a separator material 32 placed between each positive and negative plate 24, 26.

[0035] A cover 34 is provided for the housing 30, and in various embodiments, the cover includes terminal posts (or bushings) and fill tubes to allow electrolyte to be added to the ceils and to permit servicing. To prevent undesirable spillage of electrolyte from the fill tubes, and to permit exhausting of gases generated during the electrochemical reaction, a battery may also include one or more filler hole caps and/or vent cap assemblies. At least one positive and negative terminal post, generally designated 36, may be found on or about the top or front compartments of the battery. Such terminal posts 36 typically include portions which may extend through the cover and/or the front of the battery housing, depending upon the battery design. In various embodiments, the terminal posts 36 also extend through a terminal post seal assembly to help prevent leakage of acid. It will be recognized that a variety of terminal arrangements are possible, including top, side, or comer configurations known in the art.

[0036] FIG. 2 also shows an example of conventional cast-on-strap 38, which includes a rectangular, elongated body portion of a length sufficient to electrically couple each lug in a plate set and an upwardly extending member having a rounded top. FIG. 2 also illustrates a cast-on- strap 38 coupling lugs to a negative terminal 40. As shown in FIG. 2, according to various embodiments, the strap includes a body portion coupling the respective lugs in the end compartments and a post formed therewith to protrude through a cover.

[0037] Each cell element or chapter includes at least one positive plate 24, at least one negative plate 26, and optionally, a separator 32 positioned between each positive and negative plate. Separators 32 are generally provided between the plates to prevent shorting and undesirable electron flow produced during the reaction occurring in the battery.

[0038] Positive and negative electrode plates can be classified into various types according to the method of manufacturing the same. As one example, a paste type electrode is shown in FIGS. 3-5. In various embodiments, the paste type electrode includes a grid substrate 42, 46 and an electrochemically active material or “paste” 48, 50 provided on the substrate.

[0039] hi various embodiments, active materials 48, 50 are deposited in paste form on the positive and negative grid 42, 46 to create the positive plate 24 and negative plate 26, respectively. To prevent the separation of active materials 48, 50 from the plates, and to improve handling of the active materials in the manufacture of electrodes 24, 26, a pasting material or paper may be provided to the active material after deposition on the grids. The pasting paper may be provided in or on an electrode 24, 26 of a lead-acid battery.

[0040] Referring to FIGS. 3-5, the positive and negative plates 24, 26 each comprise a lead or lead alloy grid 42, 46 that supports an electrochemically active material 48, 50. The grids provide an electrical contact between the positive and negative active materials or paste 48, 50 which serves to conduct current. The grids 48, 50 as indicated also serve as a substrate for helping support electrochemically active material (e.g., paste) deposited or otherwise provided thereon during manufacture to form battery plates.

[0041] As set forth in greater detail below, known arts of lead-acid battery grid making include: (1 ) batch processes such as book mold gravity casting; and (2) continuous processes such as strip expansion, strip stamping, continuous casting, and continuous casting followed by rolling. Grids made from these processes tend to have unique features characteristic of the particular process and behave differently in lead-acid batteries, especially with respect to the pasting process. It should be appreciated that grids formed from any conventional or later- developed grid manufacturing process may be utilized, and it is not the intent to limit the invention to the grid manufacturing process disclosed herein.

[0042] In various embodiments, at least some of the grids are stamped grids. FIG. 3 illustrates one or more examples of embodiments of a stamped grid 42 (e.g., a grid for a positive plate) with active material or paste 48 provided thereon. FIG. 4 illustrates one example of a stamped grid 42 shown in FIG. 3, but without active material. In various embodiments, the stamped grid 42 includes a frame that includes a top frame element 52, first and second side frame elements 54, 56, and a bottom frame element 58. In various embodiments, the stamped grid 42 includes a series of grid wires 44 that define open areas that help hold the active material or paste 48 that helps provide current generation. In various embodiments, a current collection lug 60 is integral with the top frame element 52. While FIGS. 3-4 depict the lug 60 as offset from the center of the top frame element 52, the lug may alternatively be centered or positioned closer to either the first or second side frame elements 54, 56. The top frame element 52 may include an enlarged conductive section at least a portion of which is directly beneath the lug 60 to optimize current conduction to the lug.

[0043] The bottom frame element 58 may be formed with one or more downwardly extending feet (not shown) for spacing the remainder of the grid 42 away from the bottom of the battery container. In various embodiments, at least some of the wires 44 increase in cross- sectional area along their length from bottom to top or have a tapered shape so as to optimize the current carrying capacity of the wires to help cany away increasing current being generated from the bottom to the top. The width and spacing of the wires 44 between side elements 54, 56 may be predetermined so that there are substantially equal potential points across the width of the grid 42. To assist in supporting the electrochemical paste 48 and/or pennit the formation of paste pellets, in various embodiments, the stamped grid 42 also includes horizontal wires 62 which are equally spaced apart and are parallel to the top and/or bottom frame elements 52, 58. As shown in FIGS. 3-4, however, at least some of the horizontal wires 62 may not be equally spread apart or parallel to the top and/or bottom frame elements. The illustrated examples in FIGS. 3-4 depict an example grid pattern that is not intended to be limiting to the invention described herein.

[0044] An example embodiment of an expanded metal grid 46 (e.g., a grid for the negative plate) is illustrated in FIG. 5. In various embodiments, the expanded metal grid 46 has a pattern (e.g., a diamond pattern such as that shown in FIG. 5), which is well known in the art, with a bottom frame element 64, and a top frame element 66 that is integral with a lug 68. In other embodiments or constructions described herein, the negative plate may have a grid pattern substantially identical to the grid pattern of the positive plate.

[0045] Referring to FIGS. 3-5, the cross-section of the grid wires 44 may vary depending upon the grid making process. To help improve adhesion of the battery paste, however, in various embodiments, the grid wires may be mechanically reshaped or refinished. It should be appreciated that any number of grid wire shapes may be utilized as long as the shape provides suitable paste adhesion characteristics. For example, the cross section of wires may be of any cross-section design including substantially oval shaped, substantially rectangular, substantially diamond shape, substantially rhomboid shape, substantially hexagon shape, and/or substantially octagon shape. In the battery grid, each grid wire section may have a different cross-sectional configuration, or each grid wire section may have the same or a similar cross-sectional configuration. However, it is preferred that each grid wire section have the same cross-sectional configuration. Depending on the needs, a grid can be deformed at the vertical wire elements only, the horizontal wire elements only, or at both the vertical and horizontal wire elements.

[0046] File active material or paste 48, 50 is typically a lead-based material (e.g., PbO, PbO2, PbSO4 at different charge/discharge stages of the battery) that is pasted, deposited or otherwise provided onto the grids 42, 46. The paste composition may be determined by power requirements, cost and battery environment, as it is known in the art. Dry additives, such as fiber and expander, may also be added to the active material. For example, in various embodiments, expanders such as finely-divided carbons (e.g., lampblack or carbon black), barium sulfate, and various lignins may be included in the active material. In various embodiments, the mixture is then dried and water is re-added to form a paste of the desired consistency.

[0047] The active material 48 provided on the positive grid 42, is typically in micro-particle form, so that the electrolyte is allowed to diffuse and permeate through the lead dioxide microparticles on the positive electrode plate 24. The spongy lead, the active material 50 of the negative electrode plate 26, is typically porous and reactive, so that the electrolyte is allowed to diffuse and permeate through the spongy lead on the negative electrode plate.

[0048] FIG. 6 shows the current density between two plates or electrodes 24, 26 of a typical prior lead-acid battery 22. As shown in FIG. 6, the current (A) may be more dense toward the top 72 of the electrodes, such as for example closer to a collection lug 60, 68 of each electrode 24, 26, and the current (B) may be less dense toward the bottom 74 of the electrodes, such as for example farther from the collection lug of each electrode. The non-uniform nature of the current density in a typical lead-acid battery can result from a non-uniform internal resistance within the battery. There may be less resistance between two electrodes 24, 26 closer to the collection lugs 60, 68 of those electrodes than farther from the lugs. As a result, more current may flow (A) in areas of decreased resistance (e.g., closest to the terminals 36). The decreased current flow (B) towards the bottom 74 of the electrodes (e.g., areas of increased resistance), at least in relation to the areas of decreased resistance shown in FIG. 6, can to less utilization of the electrodes, contribute to acid stratification, and/or an increase in the production of lead sulfates. The resulting acid stratification and/or production of lead sulfates may further reduce the current flow in these regions due to, for example, a reduction in the available active material in the electrode, and may eventually lead to a premature failure of the battery.

[0049] By comparison, FIG. 7 shows a more uniform current density across the electrodes that may result from the use an electrode or electrode having a grid pattern according to one or more examples of embodiments described herein. In various embodiments, the current density (A) closest to the collection lugs 60, 68 of the electrodes 24, 26 may be decreased by increasing the resistance of the electrode in this location, at least relative to the resistance farther from the collection lugs of the electrode, which may also increase current density (B) farther from the collection lugs of the electrode. In various embodiments, the resi stance of the electrodes 24, 26 in regions farther from the collection lugs 60, 68 may be reduced, at least relative to the resistance closer to the collection lugs, to increase the current density in such regions. It should be appreciated that increasing a resistance in a first area may have the same relative effect as decreasing a resistance in a second area and vice-versa.

[0050] FIG. 8A is a front plan view of an electrode 76A having a grid pattern 78 in accordance with an example construction described herein. The electrode 76A is an electrode of a first (e.g., positive) polarity. FIG. 8B is a front plan view of an electrode 76B of a second (e.g., negati ve) polarity different from the first polarity of electrode 76A. The electrode 78B also has the grid pattern 78. The example grid pattern 78 promotes a substantially consistent or equal (e.g., uniform) current density throughout the electrode 76A, such that the current does not have a higher or significantly higher density in one area of the electrode 76 A, such as near the top frame element 80 of the electrode 76A. The grid pattern 78 draws current farther down the plate (e.g., lower in the plate) than existing grid designs, which reduces stratification, increases material utilization, and improves cycle life of the electrode 76A, and thus, the battery 22. Not only does the grid pattern 78 promote substantial uniformity of the current density between the top and bottom frame elements 80, 82 of the electrode 76A, but also promotes substantial uniformity between the first and second side frame elements 84, 86. With reference to FIG. 8A, the grid pattern 78 includes a pattern width W, a pattern length L, and has a thickness T. The patterns shown in the later figures also have pattern widths, lengths, and thicknesses.

[0051] The example grid pattern 78 depicted in FIG. 8A can be used for both the positive electrode 76A and the negative electrode (shown in FIG. 8B as 76B). In some example constructions, the negative electrode 76B may be different in thickness (e.g., thinner) than the positive electrode 76A. Additionally, collection lugs 88A, 88B on the positive electrode 76A and the negative electrode 76B, respectively, are on different sides of the electrode (e.g., on different sides of a central axis C that is common between both electrodes) so that the current flows in one side and out the other. For example, if the positive lug 88A is on a right side of the positive electrode 76A, the negative lug 88B will be on the left side of the negative electrode 76B. Positioning the collection lugs 88A, 88B of opposing sides of the central axis C of the electrodes 76A, 76B helps equalize the current density while providing the electrodes at differing locations. Though the collection lug 88A is depicted in FIG. 8 as being nearly aligned with an edge of the electrode 76A, the lug 88A may alternatively be positioned closer to the central axis C of the electrode. While the collection lugs 88A, 88B may be positioned anywhere between the central axis C and an edge of the electrode 76A, 76B, respectively, the collection lugs 88A, 88B on each electrode 76A, 76B is offset from the central axis C in one direction or the other.

[0052] The example electrodes 76A, 76B depicted in FIGS. 8A, 8B are consistent with the construction disclosed herein and has a grid pattern 78 that is mirrored or symmetrical on either side (e.g., the left and right sides) of the central axis C. While the example grid pattern 78 is an “M”-shaped pattern, other pattern styles may be used instead, with the other patterns being symmetrical about the central axis C. This mirrored configuration of grid pattern 78 is one aspect of the example construction of the electrodes 76A, 76B that promotes even current density' in the electrodes 76A, 76B to reduce stratification, increase material utilization, and improve cycle life.

[0053] The width of some of the horizontal grid paths 91 in the depicted grid pattern 78 may have a graduated (e.g., gradient, varied, etc.) thickness. That is, the horizontal grid paths 90 may have a first thickness at the top of the grid wire and a second thickness at the bottom of the grid paths. In the example construction, the horizontal grid path 90 is thicker at the bottom of the pattern 78 than at the top of the patern 78. The thickness of the horizontal grid paths 90 gradually changes (e.g., increases) from the first thickness to the second thickness. Alternatively, the thickness may change (e.g., increase) in a stepped configuration between the first thickness and the second thickness.

[0054] Also shown in FIGS. 8 A and 8B are tapered vertical paths 91. Referring to FIG. 8 A, the vertical paths 91 taper from a first thickness to a second thickness as the path progresses from the top frame element 80 towards the bottom frame element 82. Also the thickness of the vertical paths 91 vary when moving from the right (or left) frame element 86 towards the central axis A. That is, the most exterior vertical paths 91 are the thickest widths, and the most interior vertical paths 91 are the thinnest widths. [0055] The example grid pattern depicted in FIG. 8A is only one example construction of the grid pattern 78A that promotes even current distribution. This example is not intended to be limiting, and instead other grid patterns fitting one or more of the teachings in this specification that reduce stratification and/or improve the life cycle may be used with the example electrodes 76 described herein. It should also be appreciated that the above-outlined examples of embodiments may be used individually or in combination with each other or other embodiments.

[0056] FIGS. 9A-1 IB depict alternative grid patterns 94-98 that may be used with the example battery 22 described herein. The example alternative grid patterns 94-98 depicted in FIGS. 9A-1 IB each promote a substantially consistent or equal (e.g., uniform) current density throughout the electrodes 100A-104B, such that the current density is substantially consistent among the respective electrodes 100A/100B, 102A/102B, and 104A/104B. Similarly, the example grid patterns 94-98 promote movement of the cun ent farther down the grid (e.g., away from the current collection lugs 88A, 88B). For FIGS, 9A-1 IB, the patterns include a primary current path member 106-110 that helps direct current farther down into the electrode to help promote a more uniform current density. The primary current path member 106-110 is symmetrical to the central axis C, is tapered when moving away from the top frame element 80, and is directly coupled to one of the collector lugs (e.g., the positive collector lugs in the “A” drawings and the negative collector lugs in the “B” drawings).

[0057] The example grid 94 (FIGS. 9A, 9B) include a primary current path member 106 that is shaped like an inverted arch and is arcuate. The inverted arch shape (e.g., a parabola) directs the current farther down in the battery to promote a more uniform current density. The example grids 100A, 100B are symmetrical about a central axis C, however some minor variations or imperfections may exist during manufacturing. Accordingly, when referring to grids being symmetrical, they encompass substantially symmetrical designs. Additional grid paths 112 may also extend radially away from the inverted arch grid portion 100B, and grid paths 116, 118 may be thicker than grid paths 112, 114. The grid paths 112-118 can be applied to the patterns 96, 98 and vice-versa. The grid paths 120, 122 shown in FIGS. 10A-1 IB are rectangular in design with the primary current paths members 108 and 110 superimposed on the grid paths 120, 122. [0058] Similarly, the illustrated example grid patterns 96, 98 of FIGS. 10A/B and 11A/B include primary current path members 108 and 110 of other shapes that also promote uniform current density within the grid patterns 96, 98. For example, the grid patern 96 of FIGs. 10A, 10B include an inverted U-shape or truncated horseshoe shape as the primary current path member 108, The example grid pattern 98 of FIGs. HA and 11B includes primary current path member 110 comprising various angled linear segments forming substantially a W-shape. Additionally, each of the grid patterns 96, 98of FIGS. 10A''B and 11 A''B include grid paths 120, 122 extending in a rectangular grid pattern across the entirety of the electrodes. Further, while only a few example configurations are illustrated and described, many other shapes of a thicker grid portion may be implemented to promote uniform current density in an electrode.

[0059] A plate 24, 26 for a lead-acid battery is conventionally made by applying active material or paste to a conductive support such as a lead alloy grid. Plates can be classified according to the method of manufacturing the same. For example, one process for producing battery plates includes an initial step of melting hot lead in a furnace, followed by a step of feeding molten lead alloy to a strip caster. In the strip expansion process, a cast or wrought lead strip is typically pierced, stretched above and below the strip plane, and then pulled or expanded to form a grid 46 with a diamond patern. In various embodiments, the strip is coiled on a winder, and coils of lead alloy strip are stored for later use. In various embodiments, the strip may also be rolled. To form a battery grid, in various embodiments, the strip is fed through an expander that cuts, slits, and stretches a strip ofcoil to form the grids.

[0060] The grids may be produced using other known or later-developed processes. For example, as discussed above, the substrate may be formed by a casting process (e.g., by pouring a melted alloy into a mold), a stamping process, or by continuous rolling. During the manufacture of the grids or the plates, the grid wires may be refinished or reshaped (e.g., to improve adhesion of the paste).

[0061] The active material or paste 48, 50 may then be applied to or otherwise provided (e.g., pasted by a conventional paster) on the expanded strip or wire grid 42, 46. In various embodiments, one or more pasting materials or pasting papers are provided on one or both surfaces of the active material 48, 50. In various embodiments, the pasting materials or paper may be provided in a continuous process.

[0062] In various embodiments, the grids 42, 46, active material 48, 50 and pasting material or paper as described herein are fed to a divider where the strip is cut into plates 24, 26. Plates cut from the strip may be flattened or otherwise modified to help smooth out any uneven regions of paste. In various embodiments, the plates pass (e.g., on a conveyor) through an oven for flashdrying, and may then be stacked for later use. Conventionally, flash-drying may be performed using an open gas flame or an oven. After drying, the battery plates undergo a chemical treatment, well known to those skilled in the art. The pasted plates are next typically cured for many hours under elevated temperature and humidity to help oxidize any free lead and otherwise adjust the crystal structure of the plate.

[0063] After curing, the plates 24, 26 are assembled into batteries 22. Groupings of individual battery plates may be assembled, enveloped, interleaved or otherwise separated with separator material, and provided together to form plate sets 28. For example, in one common battery design, every other plate (e.g., each negative plate) in the battery set is inserted into a battery separator in the form of an envelope. The envelope acts as a separator between the plate in the envelope and the adjoining plates in the battery set. The plate sets are assembled in a container to help form a battery.

[0064] During assembly, the positive lugs 60 of the battery plates 24 are coupled together and the negative lugs 68 of the battery plates 26 are coupled together. This is typically accomplished using cast-on straps 38 formed by taking assembled battery stacks, inverting them, and dipping the lugs into molten lead provided in a mold. To permit current to follow throughout the battery, cast-on straps 38 of stacks are joined or coupled. Moreover, terminal electrodes 36 are provided which extend through the cover or casing to permit electrical contact with a vehicle’s electrical system or other system requiring or intended to use battery power.

[0065] In various embodiments, the battery housing 30, including the cover 34, is provided containing the battery cells. In various embodiments, the battery housing 30 is submerged in acidic electrolyte fluid in order to fill the battery housing with electrolyte fluid through the fill tube holes in the battery’ cover 34. After filling the battery housing 30 with electrolyte fluid, the battery 22 is removed from the electrolyte fluid. Any residual electrolyte fluid coating, dust, and other debris may be washed away to prepare the battery for shipment. Before washing the battery housing external surfaces, the fill tube holes may be plugged to prevent washing fluid from entering the battery housing.

[0066] The electrode, lead-acid battery, and method of forming the electrode and/or battery provide various advantages over existing battery designs. For example, an electrode having the grid pattern described herein provides for even current density between electrodes. As a result, the electrode and grid patern reduce, or at the least, do not contribute to acid stratification and/or sulfation within the lead-acid batery. These and other objects and advantages will be apparent from the foregoing description and appended claims.

[0067] As utilized herein, the terms “approximately,” “about,” “substantially”, and similar terms are intended to have a broad meaning in harmony with the common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. It should be understood by those of skill in the art who review this disclosure that these terms are intended to allow a description of certain features described and claimed without restricting the scope of these features to the precise numerical ranges provided. Accordingly, these terms should be interpreted as indicating that insubstantial or inconsequential modifications or alterations of the subject matter described and claimed are considered to be within the scope of the invention as recited in the appended claims.

[0068] It should be noted that references to relative positions (e.g., “top” and “bottom”) in this description are merely used to identify various elements as are oriented in the Figures. It should be recognized that the orientation of particular components may vary greatly depending on the application in which they are used.

[0069] For the purpose of this disclosure, the term “coupled” means the joining of two members directly or indirectly to one another. Such joining may be stationary in nature or moveable in nature. Such joining may be achieved with the two members or the two members and any additional intermediate members being integrally formed as a single unitary body with one another or with the two members or the two members and any additional intermediate members being attached to one another. Such joining may be permanent in na ture or may be removable or releasable in nature.

[0070] It is also important to note that the construction and arrangement of the battery or electrodes as shown in the various examples of embodiments is illustrative only. Although only a few embodiments have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited. For example, elements shown as integrally formed may be constructed of multiple parts or elements show as multiple parts may be integrally formed, the operation of the interfaces may be reversed or otherwise varied, the length or width of the structures and/or members or connector or other elements of the system may be varied, the nature or number of adjustment positions provided between the elements may be varied (e.g., by variations in the number of engagement slots or size of the engagement slots or type of engagement). The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the various examples of embodiments without departing from the spirit or scope of the present inventions.

[0071] While this invention has been described in conjunction with the examples of embodiments outlined above, various alternatives, modifications, variations, improvements and/or substantial equivalents, whether known or that are or may be presently foreseen, may become apparent to those having at least ordinary skill in the art. Accordingly, the examples of embodiments of the invention, as set forth above, are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit or scope of the invention. Therefore, the invention is intended to embrace all known or earlier developed alternatives, modifications, variations, improvements and/or substantial equivalents.