Folded bipolar battery design

Abstract

A battery includes a positive current collector and a negative current collector and a plurality of bipolar electrodes arranged in a stack between the positive and negative current collectors. The stack of the positive and negative current collectors and the plurality of bipolar electrodes is folded in an S-shape.

Description

TECHNICAL FIELD

[0001] The information provided in this section is for the purpose of generally presenting the context of the disclosure. The work of the presently named inventors, to the extent the work is originally natively described in this section, and aspects of this specification that can be inherent to their making may not be expressly cited and are not admitted to be prior art against the present disclosure.

[0002] The present disclosure relates generally to batteries, and more particularly to a folded bipolar battery design. BACKGROUND

[0003] With the proliferation of electric vehicles, the demand for batteries with compact size and relatively high energy density is increasing. Bipolar batteries are becoming increasingly popular for applications such as electric vehicles. In current designs of bipolar batteries, multiple bipolar electrodes are typically packaged in a battery container by stacking or winding the bipolar electrodes. Stacked bipolar batteries (i.e., where bipolar electrodes are stacked on top of each other in a battery container) suffer from the hazard of high contamination risk, which can be caused by electrode impact used during stacking. Stacked bipolar batteries also suffer from the hazard of internal short circuit issues, which can be caused by failure of a blocking piece used to isolate adjacent bipolar electrodes. Wound bipolar batteries (i.e., where a stack of bipolar electrodes is wound like a bundle of hay or like a roll of carpet in a battery container) suffer from the hazard of uneven pressure on the electrodes and inefficient container space utilization. Therefore, it is very challenging to package the stack of bipolar electrodes in a battery container. SUMMARY

[0004] A battery includes a positive current collector and a negative current collector and a plurality of bipolar electrodes arranged in a stack between the positive and negative current collectors. The positive and negative current collectors and the stack of the plurality of bipolar electrodes are folded in an S-shape.

[0005] In another feature, the battery further includes a plurality of layers of flexible ionically conductive film arranged between the positive and negative current collectors and between the bipolar electrodes.

[0006] In other features, each of the bipolar electrodes includes a plurality of cathodes and anodes and a bipolar current collector extending along a length of the positive and negative current collectors. The cathodes and the anodes are arranged on opposite sides of the bipolar current collector. A spacing between the cathodes and between the anodes increases from a first to a last of the bipolar electrodes in a first fold of the S-shaped stack and decreases from the last to the first of the bipolar electrodes in a second fold of the S-shaped stack.

[0007] In another feature, the battery further includes a plurality of layers of flexible ionically conductive film disposed between the positive and negative current collectors and the bipolar electrodes. The positive and negative current collectors include a plurality of cathodes and anodes, respectively. The cathodes and anodes of the plurality of bipolar electrodes and the plurality of cathodes and anodes of the positive and negative current collectors are vertically aligned with one another across the fold of the S-shaped stack. Only portions of the positive and negative current collectors, the layers of the flexible ionically conductive film, and the bipolar current collectors of the bipolar electrodes extend through the fold of the S-shaped stack.

[0008] In another feature, the battery further includes a blocking member disposed along an edge of the bipolar electrodes, between the cathodes and the anodes of the bipolar electrodes, in the spacing between the cathodes and the anodes, or both.

[0009] In other features, the positive and negative current collectors include a plurality of first and second tabs, respectively. In the S-shaped stack, the plurality of first tabs are offset relative to the plurality of second tabs.

[0010] In other features, the battery further includes an additional current collector and a plurality of second bipolar electrodes arranged in a second stack between the additional current collector and one of the positive and negative current collectors. The additional current collector and the plurality of second bipolar electrodes are S-folded with the stack of the positive and negative current collectors and the plurality of bipolar electrodes.

[0011] In another feature, the bipolar electrodes are coated with a solid state electrolyte.

[0012] In another feature, the bipolar electrodes are coated with a solid state electrolyte, the battery further including a blocking member disposed in a spacing between individual electrodes of the bipolar electrodes.

[0013] In other features, the bipolar electrodes are coated with a solid state electrolyte. Each of the bipolar electrodes includes a plurality of cathodes and anodes disposed on opposite sides of a bipolar current collector. The positive and negative current collectors include a plurality of cathodes and anodes, respectively. The cathodes and anodes of the plurality of bipolar electrodes and the plurality of cathodes and anodes of the positive and negative current collectors are vertically aligned with one another across the fold of the S-shaped stack. Only portions of the positive and negative current collectors and bipolar current collectors of the bipolar electrodes extend through the fold of the S-shaped stack.

[0014] In another feature, the battery further includes a blocking member disposed in a spacing between the cathodes and the anodes of the bipolar electrodes.

[0015] In other features, the flexible ionically conductive film includes a material that conducts ions, but not electrons. The material includes one or more of: a standalone gel, a combination of a polymer and a lithium salt, a combination of a polymer and a solid-state electrolyte, a separator and a liquid electrolyte.

[0016] In other features, the bipolar current collector provides electronic conductivity, but not ionic conductivity. The bipolar current collector includes a metal foil, a combination of a clad foil, a polymer and carbon, or a combination of a polymer and metal particles.

[0017] In other features, each of the bipolar electrodes includes a plurality of cathodes and anodes. The cathodes and the anodes include an active material that provides electronic conductivity and an ionically conductive agent that provides ionic conductivity.

[0018] In other features, the cathodes and the anodes further include carbon that provides electronic conductivity. The ionically conductive agent includes one or more of a solid-state electrolyte, a gel, a combination of a polymer and a lithium salt, or a liquid electrolyte.

[0019] In other features, each of the bipolar electrodes includes a plurality of cathodes and anodes arranged on opposite sides of a bipolar current collector. A spacing between the cathodes and between the anodes increases from a first to a last of the bipolar electrodes in a first fold of the S-shaped stack and decreases from the last to the first of the bipolar electrodes in a second fold of the S-shaped stack.

[0020] In another feature, the first and second folds are located after consecutive ones of the cathodes.

[0021] In another feature, the first and second folds are located after alternating ones of the cathodes.

[0022] In other features, each of the bipolar electrodes includes a plurality of cathodes and anodes arranged on opposite sides of a bipolar current collector. A spacing between the cathodes and between the anodes increases from a first to a last of the bipolar electrodes in a first fold of the S-shaped stack and decreases from the last to the first of the bipolar electrodes in a second fold of the S-shaped stack.

[0023] In another feature, the first and second folds are located after consecutive ones or alternating ones of the cathodes.

[0024] Other suitable applications of the disclosure will become apparent to one of ordinary skill in the art from the detailed description, claims, and drawings. The detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0025] The disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein:

[0026] Figure 1 Displaying a stack-type bipolar battery;

[0027] Figure 2 Displaying a wound-type bipolar battery;

[0028] Figure 3 Displaying an S-folded stack-type battery according to the disclosure;

[0029] Figure 4 And Figure 5 Displaying examples of bipolar electrodes used in an S-folded stack-type battery according to the disclosure;

[0030] Figures 6A-6C Displaying a folding process for manufacturing an S-folded stack-type battery according to the disclosure;

[0031] Figure 7 Displaying an exemplary layout of electrodes for manufacturing an S-folded stack-type battery according to the disclosure;

[0032] Figure 8 Displaying examples of folding schemes and layouts of tabs on current collectors of an S-folded stack-type battery according to the disclosure;

[0033] Figures 9A-10B Displaying examples of using a blocking member with an S-folded stack-type battery according to the disclosure;

[0034] Figure 11A And Figure 11B Displaying additional examples of folding and stacking schemes for manufacturing an S-folded stack-type battery according to the disclosure; and

[0035] Figures 12A-12C Displaying additional designs of bipolar electrodes according to the disclosure.

[0036] In the drawings, reference numerals can be repeated among the figures for like and / or identical elements. DETAILED DESCRIPTION

[0037] Bipolar batteries improve the energy density of a battery pack by reducing the number of connecting tabs, cell packaging, and cooling systems. However, it is challenging to package bipolar electrodes stacks inside a conventional cell container by stacking or winding. Stack-type bipolar batteries suffer from the hazards of contamination risk from electrode impact and internal short circuit risk due to blocking member failure. Wound-type bipolar batteries suffer from the hazards of uneven pressure on the electrodes and low or inefficient space utilization in the cell container.

[0038] This disclosure provides a bipolar battery design in which stacked bipolar electrodes of a certain length are folded in an S-shape, which improves space utilization in the battery container and provides significant scalability as explained below. Other features of the design include intermittent coating of the electrodes, electrode gelation, etc. These and other features of this disclosure are described in detail below.

[0039] This disclosure is organized as follows. (Reference) Figure 1 Display and description of a stacked bipolar cell. Reference Figure 2 Display and description of a wound bipolar battery. Reference Figure 3 This invention shows and describes an S-shaped folded stacked battery according to the present disclosure. References Figure 4 and Figure 5 Examples showing and describing bipolar electrodes. References. Figures 6A-6C This document shows and describes the folding process used to manufacture S-shaped foldable stacked batteries. (Reference) Figure 7 An exemplary layout of electrodes for manufacturing an S-shaped folded stacked battery is shown and described. References Figure 8 Examples showing and describing the folding schemes and layouts of the tabs on the current collector. References Figures 9A-10B This document shows and describes an example of using a blocking element with an S-shaped folded stacked battery. References Figure 11A and Figure 11B Show and describe additional examples of folding and stacking schemes. References Figures 12A-12C Show and describe additional designs for the bipolar electrodes.

[0040] Figure 1 This diagram shows a cross-section of a stack 100 of bipolar electrodes used to manufacture a stacked bipolar battery. The stack 100 comprises multiple bipolar electrodes vertically stacked one on top of the other along a vertical axis (e.g., the Z-axis of a Cartesian coordinate system). The length of the stack 100 extends along a horizontal axis (e.g., the X-axis of a Cartesian coordinate system). A continuous length of the vertically stacked bipolar electrodes (N times the length of the stack 100, where N is an integer greater than 1) is vertically sliced ​​along the Z-axis at predetermined intervals along the X-axis (i.e., along the length of the stack 100). Each slice represents a stack 100. The predetermined intervals (the length of the stack 100 along the X-axis) depend on the dimensions (e.g., length) of the bipolar battery measured along the X-axis. The multiple slices (i.e., the stack 100) are arranged vertically (i.e., stacked) one on top of the other along the Z-axis according to their dimensions (e.g., height) and the power requirements of the bipolar battery used in a particular application. The width of the stack 100 depends on the width of the bipolar battery measured along the Y-axis of a Cartesian coordinate system.

[0041] exist Figure 1In the stack 100, multiple bipolar electrodes are vertically stacked together along the Z-axis. Each bipolar electrode includes a cathode 112 and an anode 114 separated by a bipolar current collector 116. The bipolar current collector 116 conducts electrons but not lithium ions. Specifically, the bipolar current collector 116 transports electron charge carriers from the cathode to the anode (or from the anode to the cathode) in the bipolar electrode but does not transport ionic charges. The bipolar current collector 116 may be a metal foil, a foil coating (e.g., Al-Cu foil), a combination of polymer and carbon, or a combination of polymer and metal particles. A layer of gel 118 is disposed between each bipolar electrode. Specifically, the gel 118 is disposed between the cathode 112 of the bipolar electrode and the anode 114 of the adjacent bipolar electrode. A blocking element 120 is disposed on either side of the stack 100. The bipolar current collector 116 extends to the blocking element 120. Multiple stacks 100, including blocking elements 120 extending along the Z-axis on either side of multiple stacks 100, are arranged in a battery container (shown in the diagram). Figure 2 middle).

[0042] Figure 2 The diagram shows a cross-section of a wound bipolar battery, in which a continuous length of vertically stacked bipolar electrodes and several layers of gel 118 are wound in a battery container 102 like a bundle of hay or a roll of carpet (wherein the continuous length is N times the length of the stack 100, and where N is an integer greater than 1). For the sake of simplicity, the individual bipolar electrodes and the several layers of gel 118 are not shown.

[0043] The pressure on the winding stacks in regions 130-1 and 130-2 is uneven. At the bends of the winding stacks, the outer regions of 130-1 and 130-2, which are closer to the sidewalls of the battery container 102, experience greater pressure than the portions of the winding stacks farther from the sidewalls and closer to the center of the battery container 102. Furthermore, space within the battery container 102 is not being used efficiently. For example, inefficient spaces 132-1, 132-2, 132-3, and 132-4 remain unused within the battery container 102 due to the winding stacks.

[0044] Figure 3 The cross-section of an S-shaped stack 200 of bipolar electrodes is shown, wherein N vertically stacked bipolar electrodes of a certain length are folded in an S-shape along the Z-axis, where N is an integer greater than 1. Initially, the vertically stacked bipolar electrodes of a certain length are cut along the Z-axis at predetermined distances, said predetermined distances being greater than the length of the battery container measured along the X-axis. For example, the length of the vertically stacked bipolar electrodes is... Figure 1 The length of the stack 100 shown is N times the length of the stack, where N is an integer greater than 1. The vertically stacked bipolar electrodes of the length are then folded in an S-shape, and encapsulation is performed by applying pressure along the Z-axis on the folded stack to assemble the folded stack into a battery container.

[0045] Bipolar cells using an S-shaped stack design with bipolar electrodes are not susceptible to contamination caused by electrode impacts in stacked bipolar cells. S-shaped stack designs also utilize space within the battery container more efficiently than wound bipolar cells. Compared to wound bipolar cells, S-shaped stack designs have significantly less wasted space within the battery container. Furthermore, the S-shaped stack provides scalability, as the bipolar electrode stack can be folded in an S-shape along the Z-axis to any height to match the height of the battery container. Various stacking and folding schemes described below further enhance scalability.

[0046] exist Figure 3 In this structure, the S-shaped stack 200 of bipolar electrodes includes multiple bipolar electrodes vertically stacked together along the Z-axis. Each bipolar electrode includes multiple cathodes 204 and multiple anodes 206 separated by a bipolar current collector 208. The cathodes 204 and anodes are arranged on opposite sides of the bipolar current collector 208 along its length. The bipolar current collector 208 extends through the length of the S-shaped stack 200. The anodes 206 are slightly longer than the cathodes 204.

[0047] Cathodes 204 are separated from each other (i.e., spaced apart) by a first predetermined distance. Anodes 206 are separated from each other (i.e., spaced apart) by a second predetermined distance. The first and second predetermined distances are selected to allow for a vertically stacked bipolar electrode of the length between the cathodes 204 and anodes 206 to be folded as shown. Reference Figure 7 The first and second predetermined distances are shown and described in detail.

[0048] exist Figure 6A , Figure 8 , Figure 11A and Figure 11B The image shows the S-shaped stack 200 before it was folded. Figure 6A , Figure 8 , Figure 11A and Figure 11B It also shows the location where the S-shaped stack can be folded up to 200. See below for reference. Figure 4 and Figure 5 The structure of the bipolar electrode is described in further detail.

[0049] A flexible ion-conducting film 210 (hereinafter referred to as gel 210 for convenience) is disposed between each bipolar electrode. Specifically, gel 210 is disposed between the cathode 204 of the first bipolar electrode and the anode 206 of the adjacent bipolar electrode. Gel 210 extends along the X-axis through the length of the S-shaped stack 200. Bipolar current collector 208 and gel 210 extend through each bend of the S-shaped stack 200. Due to the selection of the first and second predetermined distances, the cathode 204 and anode 206 are not present in the bends (i.e., folds) of the S-shaped stack 200.

[0050] Positive current collector 220 and negative current collector 222 are arranged along the length of the S-shaped stack 200 along its first and second sides. Therefore, the positive current collector 220 and negative current collector 222 extend along the X-axis through the length of the S-shaped stack 200, including bends (i.e., folds) along the length of the S-shaped stack 200. A bipolar electrode stack and the plurality of gel layers 210 are sandwiched between the positive current collector 220 and the negative current collector 222 along the length of the S-shaped stack 200.

[0051] A positive current collector 220 is disposed above the top bipolar electrode in the S-shaped stack 200. Specifically, a layer of gel 210 is disposed on the anode 206 of the top bipolar electrode in the S-shaped stack 200, and the positive current collector 220 is disposed on the layer of gel 210 disposed on the anode 206 of the top bipolar electrode. A layer of cathode 204 is disposed on the inner surface of the positive current collector 220, such that the layer of cathode 204 on the inner surface of the positive current collector 220 is sandwiched between the inner surface of the positive current collector 220 and the layer of gel 210 disposed on the anode 206 of the top bipolar electrode.

[0052] Although the positive current collector 220 extends along the length of the S-shaped stack 200, the cathode 204 on the inner surface of the positive current collector 220 does not extend through the bends (i.e., folds) of the S-shaped stack 200 and is not present in the bends (i.e., folds) of the S-shaped stack 200. As shown, the positive current collector 220 and the adjacent layer of gel 210 are folded together with the bipolar electrode and the plurality of layers of gel 210 adjacent to the bipolar electrode. As shown, the cathodes 204 on the inner surface of the positive current collector 220 are separated from each other (i.e., spaced apart) to allow for the folding of the S-shaped stack 200.

[0053] The negative current collector 222 is disposed below the bottom bipolar electrode in the S-shaped stack 200. Specifically, a layer of gel 210 is disposed on the cathode 204 of the bottom bipolar electrode in the S-shaped stack 200, and the negative current collector 222 is disposed on the layer of gel 210 disposed on the cathode 204 of the bottom bipolar electrode. A layer of anode 206 is disposed on the inner surface of the negative current collector 222, such that the layer of anode 206 on the inner surface of the negative current collector 222 is sandwiched between the inner surface of the negative current collector 222 and the layer of gel 210 disposed on the anode 206 of the bottom bipolar electrode.

[0054] Although the negative electrode current collector 222 extends along the length of the S-shaped stack 200, the anode 206 on the inner surface of the negative electrode current collector 222 does not extend through the bend (i.e., fold) of the S-shaped stack 200 and is not present in the bend (i.e., fold) of the S-shaped stack 200. As shown, the negative electrode current collector 222 and the layered gel 210 adjacent to the negative electrode current collector 222 are folded together with the bipolar electrode and the layered gel 210 adjacent to the bipolar electrode. As shown, the anode 206 on the inner surface of the negative electrode current collector 222 are separated from each other (i.e., spaced apart) to allow the folding of the S-shaped stack 200.

[0055] Therefore, generally speaking, the S-shaped stack 200 includes N bipolar electrodes, a positive current collector 220, a negative current collector 222, and N+1 layers of gel 210, which are vertically stacked one above the other along the Z-axis in the order described above, where N is an integer greater than 1. The bipolar electrodes and the positive and negative current collectors 220 and 222 have the above-described structure.

[0056] exist Figure 3 In China (and still) Figure 6C and Figure 7 In the diagram, the N bipolar electrodes, positive current collector 220, negative current collector 222, and N+1 layers of gel 210 are shown as not in contact with each other (i.e., shown as having gaps between them) for illustrative purposes. In reality, these elements are in contact with each other (i.e., there are no gaps between them), as... Figure 6A , Figure 8 , Figure 11A and Figure 11B As shown in the image. Figure 3 The exploded view on the side shows the shading used for the different elements, which is used consistently throughout this disclosure.

[0057] The S-shaped stack 200 is encapsulated in a battery container by applying pressure along the Z-axis from the top and / or bottom. The S-shaped stack 200 is scalable because N vertically stacked bipolar electrodes of the stated length and the N+1 layers of gel 210 are folded in an S-shape along the Z-axis with the positive current collector 220 and the negative current collector 220 M times, where M is an integer greater than 1, where M is selected according to the height of the battery container, and where N and M are selected according to the power requirements of the battery.

[0058] exist Figure 3 In each fold of the S-shaped stack 200, the total length of the fold, measured along the X-axis (i.e., along the length of the battery), is the sum of the length of the bipolar electrode and the length L of the bend on either side of the bipolar electrode. The first side of the fold of the S-shaped stack 200 has the positive current collector 220 as the outermost layer, forming the first terminal of the battery. The second side of the fold of the S-shaped stack 200 has the negative current collector 222 as the outermost layer, forming the second terminal of the battery.

[0059] exist Figure 3 At the bottom, a top view of the S-shaped stack 200 is shown, where the negative current collector 222 is the last layer on top of the S-shaped stack 200. If the positive current collector 220 were the last layer on top of the S-shaped stack 200, the shading shown in the top view would be reversed.

[0060] Figure 4 The gel 210 is a flexible ion-conducting membrane. This flexible ion-conducting membrane can be a standalone gel, a combination of a polymer and a lithium salt, a combination of a polymer and a solid electrolyte, or a combination of a separator and a liquid electrolyte. This flexible ion-conducting membrane conducts lithium ions 250 (ion conduction is referred to as ionic conductivity) but does not conduct electrons 252 (electron conduction is referred to as electronic conductivity).

[0061] exist Figure 4 In this embodiment, when the flexible ion-conducting membrane comprises a combination of a separator and a liquid electrolyte, the separator includes a polymer membrane 260 forming a microporous layer. The liquid electrolyte 264 within the polymer membrane 260 fills the pores and provides maximum ion conductivity.

[0062] Figure 5 Detailed display Figure 3 The bipolar electrodes. As described above, the cathode 204 and anode 206 are arranged on opposite sides of the bipolar current collector 208. Figure 5 (as well as Figure 12A and Figure 12BThe up-facing and down-facing triangles on the sides indicate the direction of pressure applied when stacking bipolar electrodes. The bipolar electrodes are formed using any of the following methods. In the first method, a slurry is used to fabricate the bipolar electrodes. The slurry is a combination of an active material (e.g., cathode and anode materials), conductive carbon, a polymer, and a solvent for dissolving the polymer. After coating the slurry onto a foil, drying the solvent, and calendering, the bipolar electrodes are formed. The conductive carbon provides electronic conductivity within the cathode 204 or anode 206. Subsequently, a gelation process is performed on the bipolar electrodes. Specifically, the gelation process coats the cathode 204 and anode 206 with a material 270 that provides ionic conductivity. For example, the material 270 may be a gel electrolyte that provides ionic conductivity within the cathode 204 or anode 206. Alternatively, a liquid electrolyte may be used instead of a gel electrolyte.

[0063] In the second method, a slurry is used to fabricate the bipolar electrode. The slurry is a combination of an active material (e.g., cathode and anode materials), conductive carbon and a polymer, a solvent for dissolving the polymer, and a material 270 that provides ionic conductivity. After coating the slurry onto a foil, drying the solvent, and calendering, the bipolar electrode is formed. The conductive carbon provides electronic conductivity within the cathode 204 or anode 206. The material 270 provides ionic conductivity within the cathode 204 or anode 206. For example, a solid electrolyte can be used as the material 270 that provides ionic conductivity in these electrodes. Alternatively, a combination of an ionicly conductive polymer and a lithium salt can be used instead of a solid electrolyte.

[0064] Exploded views 272 and 274 further detail the internal components of these electrodes. As shown in view 272, these electrodes comprise a combination of active material 276 and carbon 278, which provides electronic conduction in these electrodes (indicated by the curved arrow above carbon 278). As shown in view 274, these electrodes comprise a combination of active material 276 and material 270, which provides ionic conduction in these electrodes. For example, material 270 may comprise a combination of a solid electrolyte, a gel, a polymer, and a lithium salt, or a liquid electrolyte. Ions 282 flow through material 270 to reach active material 276.

[0065] Figures 6A-6C This shows how the S-shaped stack 200 is formed. Figure 6A The above references are displayed. Figure 3 The continuously long bipolar electrode stack, the several layers of gel 210, and the positive current collector 220 and the negative current collector 222, as described, are thus formed in an S-shaped stack 200. Figure 6A In the diagram, the arrow points to the location where a fold is performed along the length of the stack. Folding along the length of the stack can be performed in other ways. Examples of other ways to fold along the length of the stack are shown below. Figure 11A and Figure 11B middle.

[0066] Figure 6B The way to fold the stack at the position indicated by the arrow shown in Figure 6A . Specifically, the folding follows the shape of the letter S. Figure 6C Showing the S-shaped stack 200 formed after pressing the folded stack from the top and bottom. Again, as described above with reference to Figure 3 , the S-shaped stack 200 can have any desired height measured along the Z-axis. Therefore, the description thereof is omitted for the sake of brevity.

[0067] Figure 7 Further showing in detail the spacing between the cathodes 204 and between the anodes 206 in the S-shaped stack 200. Figure 7 Showing the bipolar electrode stack of a certain length, the plurality of layers of gel 210, and the positive electrode current collector 220 and the negative electrode current collector 222 described above with reference to Figure 3 , thereby forming the S-shaped stack 200. In Figure 7 , the bipolar electrode, the plurality of layers of gel 210, and the positive electrode current collector 220 and the negative electrode current collector 222 are shown separately for illustrative purposes. In Figure 7 , L1 < L2 < L3 < L4. The values of L1, L2, L3, and L4 depend on the thickness of the electrodes and the gel 210. As described above, the anode 206 is slightly longer than the cathode 204. Therefore, the anode 206 has a larger area than the cathode 204.

[0068] The cathodes 204 on the inner surface of the positive electrode current collector 220 and the cathodes 204 of the bipolar electrodes stacked below the positive electrode current collector 220 can be regarded as arranged in rows and columns as follows. The first cathode 204 on the inner surface of the positive electrode current collector 220 and the cathode 204 of the bipolar electrode directly below the first cathode 204 can be regarded as arranged in the first column. The second cathode 204 adjacent to the first cathode 204 on the inner surface of the positive electrode current collector 220 and the cathode 204 of the bipolar electrode directly below the second cathode 204 can be regarded as arranged in the second column adjacent to the first column and so on. These column cathodes 204 are adjacent to each other along the X-axis.

[0069] The cathodes 204 on the inner surface of the positive electrode current collector 220 can be regarded as arranged in the first row. The cathode 204 of the first bipolar electrode directly below the positive electrode current collector 220 can be regarded as arranged in the second row. The cathode 204 of the second bipolar electrode directly below the first bipolar electrode can be regarded as arranged in the third row and so on. These row cathodes 204 are adjacent to each other along the Z-axis.

[0070] In Figure 7In the example shown, there are six columns and four rows of cathodes 204. In the first and second columns of cathodes 204, the cathodes 204 in the first row are spaced apart by a distance L1, the cathodes 204 in the second row by a distance L2, the cathodes 204 in the third row by a distance L3, and the cathodes 204 in the fourth row by a distance L4. In the second and third columns of cathodes 204, the cathodes 204 in the fourth row are spaced apart by a distance L1, the cathodes 204 in the third row by a distance L2, the cathodes 204 in the second row by a distance L3, and the cathodes 204 in the first row by a distance L4. This pattern of separating (i.e., spacing out) the cathodes 204 is repeated along the X-axis in subsequent columns.

[0071] Therefore, the distance between the cathodes 204 in each row of the first column and the cathodes 204 in each row of the second column increases downward along the Z-axis in the stack; the distance between the cathodes 204 in each row of the second column and the cathodes 204 in each row of the third column increases upward along the Z-axis in the stack; and this pattern is repeated in consecutive columns.

[0072] Due to the above pattern, the bipolar electrode stack, the several layers of gel 210, and the positive current collector 220 and negative current collector 222 can be folded at the positions indicated by the arrows to form... Figure 3 and Figure 6C The S-shaped stack 200 is shown in the diagram. Specifically, the above configuration causes the cathode 204 to be vertically aligned across the folds of the S-shaped stack 200. Furthermore, the above configuration ensures that the bipolar current collector 208, the plurality of gel layers 210, and the positive and negative current collectors 220 and 222 turn at each fold of the S-shaped stack 200, as shown in the diagram. Figure 3 and Figure 6C As shown in the image.

[0073] Figure 8 This shows the alignment of the tabs on the positive current collector 220 and the negative current collector 222. Figure 8 The top of the display Figure 6A The image shows a cross-sectional view of the identical bipolar electrode stack, the plurality of gel layers 210, and the positive current collector 220 and negative current collector 222. Figure 8 In the middle of the stack, in a top view, the positive current collector 220 includes a plurality of tabs 290-1, 290-2, ..., and 290-6 (collectively referred to as tabs 290). Figure 8 At the bottom of the stack, in a bottom view, the negative current collector 222 includes a plurality of tabs 292-1, 292-2, ..., and 292-6 (collectively referred to as tabs 292). When the stack is folded at the location indicated by the arrow, the tabs 290 of the positive current collector 220 are offset relative to the tabs 292 of the negative current collector 222.

[0074] Figures 9A-10BThis shows different ways of using the blocking element 300 (e.g., a polymer) with the S-shaped stack 200. Figure 9A show Figure 5 The bipolar electrodes shown are omitted, except for... Figure 5 Some details shown are focused on Figure 9A The blocking component 300 is located within the device. Figure 9A In this configuration, the blocking element 300 is used at the edge of the bipolar electrode. That is, the blocking element 300 is used on the side surface of the adjacent cathode 204 and the side surface of the adjacent anode 206 of the bipolar electrode. Figure 9B A top view of the S-shaped stack 200 is shown, in which the blocking element 300 is used at the edge of the bipolar electrode. Figure 9B Showing a bottom view of the S-shaped stack 200, where the blocking element 300 is used at the edge of the bipolar electrode. Therefore, the blocking element 300 fills... Figure 3 The area of ​​the bend (i.e., fold) of the S-shaped stack 200 shown.

[0075] Figure 10A The blocking element 300 can also be used between adjacent cathodes 204 of the bipolar electrode and between adjacent anodes 206 of the bipolar electrode. Figure 10B Showing top and bottom views of the S-shaped stack 200, wherein the blocking element 300 is used at the edge of the bipolar electrode and between adjacent cathodes 204 and anodes 206 of the bipolar electrode.

[0076] Depending on the chemical composition used in the battery, the blocking elements 300 at the four edges can be optional. For example, if the flexible ion-conducting membrane (i.e., gel 210) or ion-conducting material 270 used inside the electrodes is a gel or liquid electrolyte, then the blocking elements 300 are as follows: Figure 9A and Figure 9B The four edges shown are for preventing liquid leakage at high temperatures. If material 270 is a solid electrolyte or a combination of polymer and lithium salt, there will be no leakage of liquid material, and the blocking element 300 does not need to (but can) be as shown. Figure 9A and Figure 9B The four edges shown are used for the bipolar electrodes.

[0077] Figure 11A and Figure 11B Show / Collapse the above references Figure 3 Other configurations of continuous-length bipolar electrode stacks, several layers of gel 210, and positive current collector 220 and negative current collector 222 can be used to form S-shaped stacks 200 and other S-shaped stacks. Figure 11A show Figure 6A and Figure 8 The same heap as shown. Figure 11AThe arrows indicate locations where an S-shaped fold can be performed along the length of the stack. For example, the stack can be folded after each column of electrodes, after every other column of electrodes, in combination thereof, or in any other manner.

[0078] Figure 11B Display similar to Figure 11A The first pile is arranged on top of a second pile, which is an inverted version of the first pile, except that only one of the two piles has a negative current collector 222, which is shared by both piles. The combined pile can be folded at the location indicated by the arrow. Reference can be used. Figure 11A Other folding schemes described.

[0079] also, Figure 11B The combination of the two heaps shown can be achieved by... Figure 11A One or more heaps stacked to Figure 11B The combined stack is extended further along the Z-axis by using a shared positive current collector 220 and / or negative current collector 222 between adjacent stacks. Furthermore, with Figure 11A and Figure 11B Any folding scheme used with the S-shaped stack can be used with these extended stacks. Therefore, the S-shaped stack can be stretched not only along the Z-axis but also along the X-axis, or using a combination thereof.

[0080] A reference can be laminated before folding. Figures 3-12C The stack shown and described. The lamination temperature can be above the glass transition temperature and below the melting point of the polymer used in the adhesive used to bond the stack.

[0081] Figures 12A-12B This illustrates an additional design for the bipolar electrode according to this disclosure. Figure 12A Another example of a bipolar electrode is shown. The bipolar electrode includes a cathode 204 and an anode 206 separated by a bipolar current collector 208. The top surface of the cathode 204 is coated with a solid electrolyte 302. A layer of gel 210 is then disposed on the electrode. Subsequently, the resulting structure is stacked and sandwiched between the positive current collector 220 and the negative current collector 222, and referenced above. Figure 3 Folding is performed in the manner described above.

[0082] Figure 12B This shows another example of a bipolar electrode. The bipolar electrode in Figure 12 is different from... Figure 12A The bipolar electrode of Figure 12 does not include the plurality of gel layers 210, and includes a blocking element 304 between the cathode 204 and the anode 206. (Refer to the above text) Figure 3 After being stacked and folded in the aforementioned manner, the resulting S-shaped folded stack is shown in... Figure 12CThe above descriptions of tabs, folding schemes, and the patterns of spaced cathodes and anodes also apply. Figure 12C The S-shaped folded stack shown.

[0083] In an additional implementation, if conventional lithium-ion batteries use robust blocking elements at the edges, then Figure 1 The several layers of gel 118 shown can be extended into a conventional separator used in the battery. The resulting stack can also be folded into an S-shaped stack according to the teachings of this disclosure.

[0084] The foregoing description is illustrative in nature and is not intended to limit this disclosure, its application, or its use. The broad teachings of this disclosure can be implemented in many forms. Therefore, while this disclosure includes specific examples, its true scope should not be so limited, as other modifications will become apparent upon examination of the drawings, description, and the following claims.

[0085] It should be understood that one or more steps within the method may be performed in a different order (or simultaneously) without altering the principles of this disclosure. Furthermore, while each of the described embodiments is described above as having certain features, any one or more of those features described with respect to any embodiment of this disclosure may be implemented in and / or combined with features of any of other embodiments, even if such combination is not explicitly described. In other words, the described embodiments are not mutually exclusive, and substitutions of one or more embodiments for each other remain within the scope of this disclosure.

[0086] Various terms, including “connection,” “joint,” “coupled,” “adjacent,” “next to,” “on top of,” “above,” “below,” and “placed,” are used to describe spatial and functional relationships between elements (e.g., between modules, circuit elements, semiconductor layers, etc.). Unless explicitly described as “direct,” when describing the relationship between the first and second elements in the above disclosure, the relationship can be a direct relationship in which no other intermediate elements exist between the first and second elements, but it can also be an indirect relationship in which one or more intermediate elements exist between the first and second elements (spatially or functionally). As used herein, at least one of the phrases A, B, and C should be interpreted using the non-exclusive logic “OR” to mean logical (A or B or C) and should not be interpreted as meaning “at least one of A, at least one of B, and at least one of C.”

[0087] In the accompanying drawings, the direction of the arrows (as indicated by the arrows) generally represents the flow of information (e.g., data or instruction flow) of interest in the illustration. For example, when components A and B exchange various types of information, but the information transmitted from component A to component B is relevant to the illustration, the arrow may point from component A to component B. This unidirectional arrow does not imply that no other information is transmitted from component B to component A. Furthermore, for information sent from component A to component B, component B may send a request for said information to component A or receive confirmation of said information.

Claims

1. A battery comprising: Positive current collector and negative current collector; as well as Multiple bipolar electrodes are arranged in a stack between the positive and negative current collectors. The positive current collector, the negative current collector, and the stack of the plurality of bipolar electrodes are folded in an S-shape. Wherein, neither the first nor the second electrode of the bipolar electrode extends into the fold of the S-shaped stack; and Multiple bipolar electrodes are stacked along a vertical axis; The stack includes rows of first electrodes and rows of second electrodes of bipolar electrodes, with the first and second electrodes arranged in corresponding rows along a horizontal axis. The rows of first electrodes and rows of second electrodes are alternately arranged along a vertical axis, thereby forming columns of first and second electrodes along the vertical axis, including columns of first and second electrodes arranged alternately along the vertical axis. In each pair of adjacent columns, the distance between the first electrode in the first column row and the first electrode in the second column row increases downward along the vertical axis in the stack.

2. The battery according to claim 1, further comprising a multilayer flexible ion-conducting film disposed between the positive electrode current collector and the negative electrode current collector and disposed between the bipolar electrodes.

3. The battery according to claim 1, wherein, Each of the bipolar electrodes includes: A bipolar current collector extending along the length of the positive and negative current collectors. The first electrode and the second electrode are arranged on opposite sides of the bipolar current collector. Furthermore, the spacing between the first electrodes and between the second electrodes increases from the first to the last of the bipolar electrodes in the first fold of the S-shaped stack, and decreases from the last to the first of the bipolar electrodes in the second fold of the S-shaped stack.

4. The battery according to claim 3, further comprising: A multilayer flexible ion-conducting film is arranged between the positive electrode current collector and the negative electrode current collector, and between the bipolar electrodes; The positive current collector and the negative current collector each include multiple cathodes and anodes; In this configuration, the first and second electrodes of the plurality of bipolar electrodes, as well as the plurality of cathodes and anodes of the positive and negative current collectors, are vertically aligned with each other across the folds of the S-shaped stack; and Specifically, only certain portions of the positive and negative current collectors, the layer of the flexible ion-conducting film, and the bipolar current collector of the bipolar electrode extend through the fold of the S-shaped stack.

5. The battery of claim 3, further comprising a blocking element arranged along the edge of the bipolar electrode, in the spacing between the first electrode and the second electrode of the bipolar electrode, or both.

6. The battery according to claim 1, wherein, The positive current collector and the negative current collector each include a plurality of first and second tabs, wherein, in the S-shaped stack, the plurality of first tabs are offset relative to the plurality of second tabs.

7. The battery according to claim 1, further comprising: Additional current collectors; as well as A plurality of second bipolar electrodes are arranged in a second stack between the additional current collector and one of the positive current collector and the negative current collector. The additional current collector and the plurality of second bipolar electrodes are folded together in an S-shape with the positive current collector, the negative current collector, and the stack of the plurality of bipolar electrodes.

8. The battery according to claim 1, wherein, The bipolar electrode is coated with a solid electrolyte.

9. The battery according to claim 1, wherein, The bipolar electrodes are coated with a solid electrolyte, and the battery further includes a blocking element disposed in the spacing between the individual electrodes of the bipolar electrodes.

10. The battery according to claim 1, wherein: The bipolar electrode is coated with a solid electrolyte; Each of the bipolar electrodes includes a plurality of cathodes and anodes arranged on opposite sides of the bipolar current collector; The positive current collector and the negative current collector each include multiple cathodes and anodes; The first and second electrodes of the plurality of bipolar electrodes, as well as the plurality of cathodes and anodes of the positive and negative current collectors, are vertically aligned with each other across the folds of the S-shaped stack; and Specifically, only a portion of the positive current collector and the negative current collector, and the bipolar current collector of the bipolar electrode, extend through the fold of the S-shaped stack.

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