WO2021247488A1 - Seal systems for bipole frames and bipolar batteries including the same - Google Patents

Abstract

A bipole frame assembly for a bipolar battery includes: a bipole frame including first and second opposite surfaces; a negative bipole lead sheet on the first surface of the bipole frame; a positive bipole lead sheet on the second surface of the bipole frame; a continuous first track of sealant on each of the first and second surfaces; and a plurality of continuous second tracks of sealant on each of the first and second surfaces. The first track of sealant and the plurality of second tracks of sealant on the first surface are between the bipole frame and the negative bipole lead sheet, and the first track of sealant and the plurality of second tracks of sealant on the second surface are between the bipole frame and the positive bipole lead sheet.

Description

Seal Systems for Bipole Frames and Bipolar Batteries Including the Same

Related Applications

[0001] This application claims priority from U.S. Provisional Application No. 63/033,567, filed June 2, 2020, the disclosure of which is incorporated by reference in its entirety.

Background

[0002] In some known bipolar batteries, multiple solder joints are used between positive and negative lead foil on adjacent half cells. These solder joints perform two functions: 1) provide electrical connection between adjacent half cells, and 2) provide a hermetic seal between adjacent half cells. If the solder joints are not completely formed or if the solder joints corrode over time, then the risk of electrochemical leakage that will destroy the battery increases dramatically.

Summary

[0003] Some embodiments of the present invention are directed to a bipole frame assembly for a bipolar battery, the bipole frame assembly including: a bipole frame including first and second opposite surfaces; a negative bipole lead sheet on the first surface of the bipole frame; a positive bipole lead sheet on the second surface of the bipole frame; a continuous first track of sealant on each of the first and second surfaces; and a plurality of continuous second tracks of sealant on each of the first and second surfaces. The first track of sealant and the plurality of second tracks of sealant on the first surface may be between the bipole frame and the negative bipole lead sheet, and the first track of sealant and the plurality of second tracks of sealant on the second surface may be between the bipole frame and the positive bipole lead sheet.

[0004] In some embodiments, the bipole frame assembly further includes: a well on the first surface adjacent a perimeter of the bipole frame and including first and second sidewalls that extend outwardly from the first surface; and a well on the second surface adjacent the perimeter of the bipole frame and including first and second sidewalls that extend outwardly from the second surface. The first track of sealant on the first surface may be in the well on the first surface and the first track of sealant on the second surface may be in the well on the second surface. [0005] In some embodiments, first track of sealant on the first surface extends over the first and second sidewalls of the well on the first surface and contacts the first surface on opposite sides of the well, and the first track of sealant on the second surface extends over the first and second sidewalls of the well on the second surface and contacts the second surface on opposite sides of the first well.

[0006] In some embodiments, the negative bipole lead sheet includes a substantially rectangular raised portion where the first track of sealant on the first surface contacts the negative bipole lead sheet, and the positive bipole lead sheet includes a substantially rectangular raised portion where the first track of sealant on the second surface contacts the positive bipole lead sheet.

[0007] In some embodiments, a plurality of through holes are defined in the bipole frame, one of the plurality of second tracks of sealant on the first surface surrounds each of the through holes on the first surface, and one of the plurality of second tracks of sealant on the second surface surrounds each of the through holes on the second surface.

[0008] In some embodiments, the bipole frame assembly further includes: a plurality of second wells on the first surface each including first and second sidewalls, with one of the plurality of second wells on the first surface surrounding each of the through holes and with one of the second tracks of sealant on the first surface in each first well; and a plurality of second wells on the second surface and including first and second sidewalls, with one of the plurality of second wells on the second surface surrounding each of the through holes and with one of the second tracks of sealant on the second surface in each second well.

[0009] In some embodiments, each of the second wells on the first surface is circular and each of the second wells on the second surface is circular.

[0010] In some embodiments, the bipole frame assembly further includes: a plurality of first bosses extending outwardly from the first surface with one of the first bosses surrounding one of the through holes; and a plurality of second bosses extending outwardly from the second surface with one of the second bosses surrounding one of the through holes. One of the plurality of second wells on the first surface may surround one or each of the first bosses, and wherein one of the plurality of second wells on the second surface may surround one or each of the second bosses.

[0011] In some embodiments, the bipole frame assembly further includes an electrolyte fill through hole defined in the bipole frame. One of the plurality of second wells on the first surface may surround the electrolyte fill through hole on the first surface, and one of the plurality of second wells on the second surface may surround the electrolyte fill through hole on the second surface.

[0012] In some embodiments, the negative bipole lead sheet includes a circular raised portion where each second track of sealant on the first surface contacts the negative bipole lead sheet, and the positive bipole lead sheet includes a circular raised portion where each second track of sealant on the second surface contacts the positive bipole lead sheet.

[0013] In some embodiments, the first track of sealant and the plurality of second tracks of sealant include RTV silicone.

[0014] Some other embodiments of the present invention are directed to a method for assembling a bipole frame assembly for a bipolar battery, the method including: providing a bipole frame including first and second opposite surfaces, a plurality of through holes, a first well on each of the first and second surfaces, and a plurality of second wells on each of the first and second surfaces, wherein the first well is adjacent and extends along a perimeter of the bipole frame, and wherein one of the plurality of second wells surrounds each of the through holes; dispensing a first continuous track of sealant in the first well on the first surface and dispensing a second continuous track of sealant in each of the plurality of second wells on the first surface; placing the bipole frame on a first bipole lead sheet with the first surface facing the first bipole lead sheet; dispensing a first continuous track of sealant in the first well on the second surface and dispensing a second continuous track of sealant in each of the plurality of second wells on the second surface; placing a second bipole lead sheet on the bipole frame with the second surface facing the second bipole lead sheet; and compressing the bipole frame and the bipole lead sheets.

[0015] Some other embodiments of the present invention are directed to a bipolar battery including: a positive end frame; a negative end frame; and a plurality of bipole frame assemblies between the positive end frame and the negative end frame. Each biople frame assembly may include: a negative bipole lead sheet on the first surface of the bipole frame; a positive bipole lead sheet on the second surface of the bipole frame; a continuous first track of sealant on each of the first and second surfaces; and/or a plurality of continuous second tracks of sealant on each of the first and second surfaces. The first track of sealant and/or the plurality of second tracks of sealant on the first surface may be between the bipole frame and the negative bipole lead sheet, and the first track of sealant and/or the plurality of second tracks of sealant on the second surface may be between the bipole frame and the positive bipole lead sheet.

[0016] Further features, advantages and details of the present invention will be appreciated by those of ordinary skill in the art from a reading of the figures and the detailed description of the preferred embodiments that follow, such description being merely illustrative of the present invention.

Brief Description of the Drawings

[0017] Figure l is a perspective view of a bipolar battery according to some embodiments of the present invention.

[0018] Figure 2 is another perspective view of the bipolar battery of Figure 1.

[0019] Figure 3 is a schematic sectional view of the bipolar battery of Figure 1.

[0020] Figure 4 is a sectional view of the bipolar battery of Figure 1.

[0021] Figure 5 is a perspective view of a bipole frame according to some embodiments of the present invention.

[0022] Figure 6 is another perspective view of the bipole frame of Figure 5.

[0023] Figure 7 is a fragmentary sectional view taken along line 7-7 of Figure 5.

[0024] Figure 8 is a fragmentary sectional view taken along line 8-8 of Figure 5.

[0025] Figures 9 and 10 are plan views of the bipole frame of Figure 5 with sealant applied to the frame.

[0026] Figure 11 is a fragmentary sectional view of thee bipole frame of Figure 9.

[0027] Figure 12 is a perspective view of a bipole frame assembly according to some embodiments of the present invention.

[0028] Figure 13 is another perspective view of the bipole frame assembly of Figure 12.

[0029] Figures 14A and 14B are fragmentary sectional views of the bipole frame assembly of Figure 12.

[0030] Figures 15 and 16 are perspective views of the bipolar frame assembly of Figure 12 after compression of the bipole frame and the lead sheets. Detailed Description

[0031] The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which illustrative embodiments of the invention are shown. In the drawings, the relative sizes of regions or features may be exaggerated for clarity. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0032] It will be understood that when an element is referred to as being "coupled" or "connected" to another element, it can be directly coupled or connected to the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly coupled" or "directly connected" to another element, there are no intervening elements present. Like numbers refer to like elements throughout. As used herein the term "and/or" includes any and all combinations of one or more of the associated listed items.

[0033] In addition, spatially relative terms, such as "under," "below," "lower," "over," "upper" and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is inverted, elements described as "under" or "beneath" other elements or features would then be oriented "over" the other elements or features. Thus, the exemplary term "under" can encompass both an orientation of over and under. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0034] Well-known functions or constructions may not be described in detail for brevity and/or clarity.

[0035] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises," "comprising," "includes" and/or "including," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

[0036] It is noted that any one or more aspects or features described with respect to one embodiment may be incorporated in a different embodiment although not specifically described relative thereto. That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination. Applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to be able to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner. These and other objects and/or aspects of the present invention are explained in detail in the specification set forth below.

[0037] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0038] A bipolar battery 10 according to some embodiments is shown in Figures 1-4. The battery 10 includes a positive end frame or plate 12, a negative end frame or plate 14, and a central outer casing 16. The positive end frame 12, the negative end frame 14, and the central outer casing 16 may be referred to herein as the battery casing 18.

[0039] A positive terminal 17 may be at the positive end frame 12 and a negative terminal 19 may be at the negative end frame 14.

[0040] Figure 3 is a simplified schematic of the bipolar battery 10 with some features omitted including the battery casing. The battery 10 includes a stack S of plates, frames, and/or material layers. Starting at the left side of the drawing, the battery includes the positive end frame 12, a positive end frame lead foil or sheet 20, positive active material (PAM) 22, a separator 24, negative active material (NAM) 26, a negative bipole lead foil or sheet 28, and a bipole frame 30. The next cell or module includes a positive bipole lead foil or sheet 32, the PAM 22, the separator 24, the NAM 26, and the negative bipole lead foil or sheet 28. This same sequence is continued in the stack S until, at the right side of the drawing, there is a negative end frame lead foil or sheet 34 and the negative end frame 14.

[0041] Referring to Figures 1 and 4, one or more stabilization channels 36 may extend through the stack S. The stabilization channels 36 may be defined by aligned holes or apertures defined in the positive end frame 12, the positive end frame lead sheet 20, the negative end frame 14, the negative end frame lead sheet 34, the bipole frames 30, the negative bipole lead sheets 28, and/or the positive bipole lead sheets 32.

[0042] A stabilization member 38 may be received in each of the stabilization channels 36. The stabilization members 38 may be a fastener such as a bolt, post, or rod. The stabilization member 38 may be an elongated polymer member that is injected into the stabilization channels 36. The stabilization members 38 may provide mechanical stability and strength for the stack S. [0043] Although eight channels 36 and corresponding stabilization members 38 are illustrated, it is contemplated that a lesser or greater number of channels and corresponding stabilization members may be used.

[0044] An electrolyte channel or manifold 40 extends at least partially through the stack S. The electrolyte channel 40 may be defined by aligned holes or apertures defined in the positive end frame lead sheet 20, the negative end frame lead sheet 34, the bipole frames 30, the negative bipole lead sheets 28, and/or the positive bipole lead sheets 32. An electrolyte fill port 42 in fluid communication with the electrolyte channel 40 may be on the positive end frame 12. In other embodiments, the fill port 42 may be positioned differently (e.g., on the negative end frame 14).

[0045] Each separator 24 may include an electrolyte storage reservoir. The electrolyte channel 40 may supply electrolyte to each electrolyte storage reservoir.

[0046] Figures 5 and 6 are perspective views of the bipole frame 30. The bipole frame 30 includes a body 44 having first and second opposite primary sides or surfaces 46, 48. The body 44 of the bipole frame 30 may be formed of a polymer such as ABS.

[0047] One or more bosses 50A extend outwardly from the first surface 46. One or more bosses 50B extend outwardly from the second surface 48. The bosses 50A, 50B surround stabilization through holes 52 that partially define the stabilization channels 36 described above. [0048] A boss 54A extends outwardly from the first surface 46. A boss 54B extends outwardly from the second surface 48. The bosses 54A, 54B surround an electrolyte through hole 56 that partially defines the electrolyte fill channel 40 described above.

[0049] A plurality of solder through holes 58 extend through the body 44. Solder is dispensed in the solder through holes 58 to form a joint for lead sheets on each of the first and second surfaces 46, 48.

[0050] A first well 60 A may be on the first surface 46 adjacent an outer perimeter 62 of the bipole frame 30. A first well 60B may be on the second surface 48 adjacent the outer perimeter 62 of the bipole frame 30. The wells 60A, 60B may be generally rectangular and may completely surround the stabilization through holes 52, the electrolyte through hole 56, and/or the solder through holes 58.

[0051] Figure 7 is a sectional view taken along line 7-7 in Figure 5. The well 60A includes a first or inner sidewall 64 and a second or outer sidewall 66 that each extend outwardly from the first surface 46 of the bipole frame 30. The first sidewall 64, the second sidewall 66, and the first surface 46 define the well 60A.

[0052] Similarly, the well 60B includes a first or inner sidewall 68 and a second or outer sidewall 70 that each extend outwardly from the second surface 48 of the bipole frame 30. The first sidewall 68, the second sidewall 70, and the second surface 48 define the well 60B.

[0053] In some other embodiments, the wells may be recessed regions in the first surface 46 and/or second surface 48 of the bipole frame 30.

[0054] Referring again to Figures 5 and 6, a plurality of second wells 72A may be on the first surface 46 of the bipole frame 30. The wells 72A may be circular and may surround corresponding ones of the stabilization through holes 52 and the electrolyte through holes 56.

The wells 72A may surround the bosses 50A and 54A. Similarly, a plurality of second wells 72B may be on the second surface 48 of the bipole frame 30. The wells 72B may be circular and may surround corresponding ones of the stabilization through holes 52 and the electrolyte through holes 56. The wells 72B may surround the bosses 50B and 54B.

[0055] Figure 8 is a sectional view taken along line 8-8 in Figure 5. The well 72A includes a first or inner sidewall 76 and a second or outer sidewall 78 that each extend outwardly from the first surface 46 of the bipole frame 30. The first sidewall 76, the second sidewall 78, and the first surface 46 define the well 72A. [0056] Similarly, the well 72B includes a first or inner sidewall 80 and a second or outer sidewall 82 that each extend outwardly from the second surface 48 of the bipole frame 30. The first sidewall 80, the second sidewall 82, and the second surface 48 define the well 72B.

[0057] In some other embodiments, the wells may be recessed regions in the first surface 46 and/or second surface 48 of the bipole frame 30.

[0058] Referring to Figures 5 and 9, a track of sealant 84A may be dispensed in the first well 60A. Tracks of sealant 86A may be dispensed in the second wells 72A.

[0059] Referring to Figures 6 and 10, a track of sealant 84B may be dispensed in the first well 60B. Tracks of sealant 86B may be dispensed in the second wells 72B.

[0060] The sealant may flow freely while being dispensed and cure at room temperature. In some embodiments, the sealant is room temperature vulcanizing (RTV) silicone.

[0061] The tracks of sealant may extend out of or above the wells. That is, the sealant may be dispensed such that that the track extends farther from the surface 46, 48 of the bipole frame 30 than do the sidewalls that define the well. The sealant may be dispensed such that that the sealant is proud of the surface 46, 48 of the bipole frame 30. This may help ensure that the sealant is spread over a greater area when the lead sheets are compressed onto the bipole frame. [0062] This is illustrated in Figure 11. The sealant 84A is in the well 60A and extends farther from the first surface 46 of the bipole frame 30 than do the sidewalls 64, 66 of the well 60A. Similarly, the sealant 84B is in the well 60B and extends farther from the second surface 48 of the bipole frame 30 than do the sidewalls 68, 70 of the well 60B. It will be appreciated that the sealant 86A and 86B may be dispensed in the wells 72A and 72B in the same or similar way. [0063] Figures 12 and 13 are perspective views of the bipole frame assembly 60. The bipole frame assembly 60 includes the bipole frame 30, the negative bipole lead sheet 28 on the first surface 46, and the positive bipole lead sheet 32 on the second surface 48. A solder joint 86 is in each of the solder through holes 58 between the negative bipole lead sheet 28 and the positive bipole lead sheet 32.

[0064] Figures 14A and 14B are sectional views showing the wells and sealant after the bipole frame and lead sheets have been compressed. Figure 14A shows that a portion of the sealant 84A has been pressed out of the well 60A such that a portion of the sealant 84A is between the first surface 46 of the bipole frame 30 and the negative bipole lead sheet 28 (e.g., outside or adjacent outer side surfaces of the sidewalls 64, 66). Similarly, a portion of the sealant 84B has been pressed out of the well 60B such that a portion of the sealant 84B is between the second surface 48 of the bipole frame 30 and the positive bipole lead sheet 32 (e.g., outside or adjacent outer side surfaces of the sidewalls 68, 70).

[0065] Figure 14B shows that a portion of the sealant 86A has been pressed out of the well 72A such that a portion of the sealant 86A is between the first surface 46 of the bipole frame 30 and the negative bipole lead sheet 28 (e.g., outside or adjacent outer side surfaces of the sidewalls 76, 78). Similarly, a portion of the sealant 86B has been pressed out of the well 72B such that a portion of the sealant 86B is between the second surface 48 of the bipole frame 30 and the positive bipole lead sheet 32 (e.g., outside or adjacent outer side surfaces of the sidewalls 80,

82).

[0066] Figures 15 and 16 are perspective views of the bipole frame assembly 60 after the bipole frame and lead sheets have been compressed. It can be seen that the negative bipole lead sheet 28 includes raised areas 90A and 92A where the lead foil 28 contacts the sealant 84A and 86A, respectively.

[0067] Similarly, it can be seen that the positive bipole lead sheet 32 includes raised areas 90B and 92B where the lead foil 32 contacts the sealant 84B and 86B, respectively. The raised areas may provide visual confirmation that a robust seal has been formed.

[0068] Referring again to Figures 5 and 6, in some embodiments, a plurality of lead sheet retainer bosses 96A and 96B may be on the first surface 46 and the second surface 48 of the bipole frame 30, respectively. The retainer bosses 96A may be between the first well 60A and the outer perimeter 62 of the bipole frame 30. The retainer bosses 96B may be between the first well 60B and the outer perimeter 62 of the bipole frame 30.

[0069] The retainer bosses 96A may extend outwardly away from the first surface 46 of the bipole frame 30. The retainer bosses 96B may extend outwardly away from the second surface 48 of the bipole frame 30.

[0070] The retainer bosses 96A and 96B may help prevent peeling or pulling of the sealant joints during assembly. The retainer bosses perform multiple functions: 1) they keep the lead sheets “coplanar” with the bipole frame to ensure that the sealant is not disturbed before curing, 2) they allow for immediate manufacturing without requiring the sealant to cure, and 3) they ensure the lead sheets maintain a planar shape in ensuing manufacturing processes. Further, the retainer bosses when heat formed capture the lead sheet and maintain intimate contact between the lead sheet and the bipole frame at the bosses.

[0071] An example process for assembling the bipole frame assembly 60 will now be described. The negative bipole lead sheet 28 may be placed onto a solder paste dispense station fixture. The bipole frame 30 may be placed onto a sealant dispense station with the negative side facing upward. Sealant may be dispensed onto the negative side of the bipole frame 30. The bipole frame 30 with the sealant may be removed from the sealant dispense station, flipped, and placed on top of the negative bipole lead sheet 28 in the solder dispense station with the sealant touching the lead. Solder paste may be dispensed onto the bipole frame and lead assembly (e.g., into the solder through holes 58). The bipole frame and lead assembly may be removed from the solder paste dispense station and placed in the sealant dispense station. Sealant may be applied to the positive side of the bipole frame 30. The bipole frame and lead assembly may be returned to the solder paste dispense station and the positive bipole lead sheet 32 may be placed on top of the bipole frame 30. The assembly may be moved to a solder paste reflow station and the solder paste may be heated and reflowed. The lead sheets 28, 32 may be pressed against the bipole frame 30 to achieve the desired geometry in the sealing areas (e.g., the wells 60, 72). Heat and pressure may be applied to melt and reform (e.g., flatten) the lead sheet retainer bosses 96 A, 96B (see Figures 15 and 16).

[0072] Some known bipole frame designs incorporate multiple solder joints between the positive and negative lead sheets on adjacent half cells. These solder joint perform two functions: 1) provide an electrical connection between adjacent half cells, and 2) provide a hermetic seal between adjacent half cells. If the solder joints are not completely formed or if the solder joint corrode over time, then the risk of electrochemical leakage that will destroy the battery increases dramatically.

[0073] The current state of the art requires a large number of solder dots to be perfectly formed to develop an electrochemical seal and this is not practical to achieve. For example, in a known golf cart bipolar battery design there are 112 solder dots in each bipole frame. If the solder joint manufacturing process is 99.99% reliable, then leak free frame yield would be 98.9%. If frames with this defect rate are introduced into a 48 volt DC battery, the yield would drop to 77.3%.

This is an unacceptable manufacturing yield and the batteries would not support long service life applications. [0074] Embodiments of the present invention eliminate the hermetic sealing function of the solder joint and replace it with a primary seal. The primary seal comprises liquid sealant dispensed in wells that surround the bipole frame’s perimeter as well as any penetration within the bipole frame such as the stabilization through holes or the electrolyte fill port. The wells contain the sealant material after the dispense operation and may also ensure a minimum sealant thickness after lead sheet compression during the assembly process.

[0075] The foregoing is illustrative of the present invention and is not to be construed as limiting thereof. Although a few exemplary embodiments of this invention have been described, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the claims. The invention is defined by the following claims, with equivalents of the claims to be included therein.

Claims

Claims:

1. A bipole frame assembly for a bipolar battery, the bipole frame assembly comprising: a bipole frame comprising first and second opposite surfaces; a negative bipole lead sheet on the first surface of the bipole frame; a positive bipole lead sheet on the second surface of the bipole frame; a continuous first track of sealant on each of the first and second surfaces; and a plurality of continuous second tracks of sealant on each of the first and second surfaces; wherein the first track of sealant and the plurality of second tracks of sealant on the first surface are between the bipole frame and the negative bipole lead sheet, and wherein the first track of sealant and the plurality of second tracks of sealant on the second surface are between the bipole frame and the positive bipole lead sheet.

2. The bipole frame assembly of claim 1 further comprising: a well on the first surface adjacent a perimeter of the bipole frame and comprising first and second sidewalls that extend outwardly from the first surface; and a well on the second surface adjacent the perimeter of the bipole frame and comprising first and second sidewalls that extend outwardly from the second surface, wherein the first track of sealant on the first surface is in the well on the first surface and the first track of sealant on the second surface is in the well on the second surface.

3. The bipole frame assembly of claim 2 wherein the first track of sealant on the first surface extends over the first and second sidewalls of the well on the first surface and contacts the first surface on opposite sides of the well, and wherein the first track of sealant on the second surface extends over the first and second sidewalls of the well on the second surface and contacts the second surface on opposite sides of the first well.

4. The bipole frame assembly of claim 2 wherein the negative bipole lead sheet comprises a substantially rectangular raised portion where the first track of sealant on the first surface contacts the negative bipole lead sheet, and wherein the positive bipole lead sheet comprises a substantially rectangular raised portion where the first track of sealant on the second surface contacts the positive bipole lead sheet.

5. The bipole frame assembly of claim 1 wherein a plurality of through holes are defined in the bipole frame, wherein one of the plurality of second tracks of sealant on the first surface surrounds each of the through holes on the first surface, and wherein one of the plurality of second tracks of sealant on the second surface surrounds each of the through holes on the second surface.

6. The bipole frame assembly of claim 5 further comprising: a plurality of second wells on the first surface each comprising first and second sidewalls, with one of the plurality of second wells on the first surface surrounding each of the through holes and with one of the second tracks of sealant on the first surface in each first well; and a plurality of second wells on the second surface and comprising first and second sidewalls, with one of the plurality of second wells on the second surface surrounding each of the through holes and with one of the second tracks of sealant on the second surface in each second well.

7. The bipole frame assembly of claim 6 wherein each of the second wells on the first surface is circular and each of the second wells on the second surface is circular.

8. The bipole frame assembly of claim 6 further comprising: a plurality of first bosses extending outwardly from the first surface with one of the first bosses surrounding one of the through holes; and a plurality of second bosses extending outwardly from the second surface with one of the second bosses surrounding one of the through holes, wherein one of the plurality of second wells on the first surface surrounds one of the first bosses, and wherein one of the plurality of second wells on the second surface surrounds one of the second bosses.

9. The bipole frame assembly of claim 6 further comprising an electrolyte fill through hole defined in the bipole frame, wherein one of the plurality of second wells on the first surface surrounds the electrolyte fill through hole on the first surface, and wherein one of the plurality of second wells on the second surface surrounds the electrolyte fill through hole on the second surface.

10. The bipole frame assembly of claim 5 wherein the negative bipole lead sheet comprises a circular raised portion where each second track of sealant on the first surface contacts the negative bipole lead sheet, and wherein the positive bipole lead sheet comprises a circular raised portion where each second track of sealant on the second surface contacts the positive bipole lead sheet.

11. The bipole frame assembly of claim 1 wherein the first track of sealant and the plurality of second tracks of sealant comprise RTV silicone.

12. A method for assembling a bipole frame assembly for a bipolar battery, the method comprising: providing a bipole frame comprising first and second opposite surfaces, a plurality of through holes, a first well on each of the first and second surfaces, and a plurality of second wells on each of the first and second surfaces, wherein the first well is adjacent and extends along a perimeter of the bipole frame, and wherein one of the plurality of second wells surrounds each of the through holes; dispensing a first continuous track of sealant in the first well on the first surface and dispensing a second continuous track of sealant in each of the plurality of second wells on the first surface; placing the bipole frame on a first bipole lead sheet with the first surface facing the first bipole lead sheet; dispensing a first continuous track of sealant in the first well on the second surface and dispensing a second continuous track of sealant in each of the plurality of second wells on the second surface; placing a second bipole lead sheet on the bipole frame with the second surface facing the second bipole lead sheet; and compressing the bipole frame and the bipole lead sheets.

13. A bipolar battery comprising: a positive end frame; a negative end frame; and a plurality of bipole frame assemblies between the positive end frame and the negative end frame, wherein each biople frame assembly comprises: a bipole frame comprising first and second opposite surfaces; a negative bipole lead sheet on the first surface of the bipole frame; a positive bipole lead sheet on the second surface of the bipole frame; a continuous first track of sealant on each of the first and second surfaces; and a plurality of continuous second tracks of sealant on each of the first and second surfaces; wherein the first track of sealant and the plurality of second tracks of sealant on the first surface are between the bipole frame and the negative bipole lead sheet, and wherein the first track of sealant and the plurality of second tracks of sealant on the second surface are between the bipole frame and the positive bipole lead sheet.