Power storage cell

Abstract

To improve an impregnation speed of an electrolyte.SOLUTION: A power storage cell includes a case, an electrode body, an insulator film, and an electrolyte. The case stores the electrode body, the insulator film and the electrolyte therein. The electrode body includes a top face, a bottom face and a peripheral face. In the case, a liquid injection hole is provided on a face opposed to the top face. The peripheral face connects the top face and the bottom face. The peripheral face includes a first region and a second region. The first region is covered by the insulator film. The second region is not covered by the insulator film. The second region extends from the top face to the bottom face. The second region has a smaller area in relative to the first region.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to an energy storage cell. [Background technology]

[0002] Japanese Patent Application Laid-Open Publication No. 2016-100270 discloses an insulating tape that is joined to the outermost periphery of an electrode body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-100270 A Summary of the Invention [Problem to be solved by the invention]

[0004] The energy storage cell includes a case and an electrode assembly. The case houses the electrode assembly. After the electrode assembly is housed, an electrolyte is injected into the case. From the viewpoint of the energy density of the energy storage cell, it is required to reduce the clearance between the case and the electrode assembly. The smaller the clearance, the less the electrolyte flow path around the electrode assembly. Therefore, it tends to take a long time for the electrolyte to spread throughout the electrode assembly. In other words, there is room for improvement in the impregnation speed of the electrolyte.

[0005] The objective of the present disclosure is to increase the impregnation rate of the electrolyte. [Means for solving the problem]

[0006] The technical configuration and the effects of the present disclosure will be described below. However, the mechanism of action includes assumptions. The mechanism of action does not limit the technical scope of the present disclosure.

[0007] 1. The energy storage cell includes a case, an electrode body, an insulating film, and an electrolyte. The case houses the electrode body, the insulating film, and the electrolyte. The electrode body has an upper surface, a lower surface, and a peripheral surface. The case has a liquid injection hole on the surface opposite the upper surface. The peripheral surface connects the upper surface and the lower surface. The peripheral surface includes a first region and a second region. The first region is covered by an insulating film. The second region is not covered by the insulating film. The second region extends from the upper surface to the lower surface. The second region has a smaller area than the first region.

[0008] The electrolyte injected through the injection hole is supplied to the upper surface of the electrode body. Depending on the thickness of the insulating film, a gap may be formed between the second region and the case. This gap serves as a flow path for the electrolyte, allowing the electrolyte to be rapidly supplied from the upper surface to the lower surface. This is expected to improve the impregnation speed.

[0009] 2. The storage cell of "1" above may include, for example, the following configuration. The energy storage cell further includes an insulating member. The insulating member is disposed in the case at a position facing the second region.

[0010] The insulating member may electrically insulate the second region from the case.

[0011] 3. The storage cell of "1" or "2" above may include, for example, the following configuration. The second region is disposed below the liquid injection hole.

[0012] By disposing the second region below the injection hole, it is expected that the impregnation speed will be improved.

[0013] 4. The storage cell according to any one of the above items "1" to "3" may include, for example, the following configuration. The energy storage cell further includes an insulating tape, the second region being sandwiched between the first regions in the circumferential direction of the circumferential surface, and the insulating tape extending across the second regions to bridge the first regions.

[0014] The insulating tape may electrically insulate the second region from the case.

[0015] 5. The storage cell according to any one of the above items "1" to "4" may include, for example, the following configuration. The insulating film is in the form of a strip.

[0016] The belt-shaped insulating film is suitable for application to a peripheral surface. By using the belt-shaped insulating film, for example, improvement in productivity can be expected.

[0017] 6. The storage cell according to any one of the above items "1" to "5" may include, for example, the following configuration. The insulating film is wrapped around the periphery.

[0018] 7. The storage cell according to any one of the above items "1" to "6" may include, for example, the following configuration. The insulating film has a length direction and a width direction. The width direction is perpendicular to the length direction. The length direction is shorter than the perimeter of the peripheral surface.

[0019] Since the length dimension of the insulating film is shorter than the perimeter of the peripheral surface, gaps may be formed between the insulating film and the starting end and the ending end when the insulating film is wrapped around the peripheral surface, i.e., a second region may be formed.

[0020] 8. The storage cell according to any one of the above items "1" to "7" may include, for example, the following configuration. The electrode body has a cubic outer shape. The electrode body is of a laminated type.

[0021] 9. The storage cell according to any one of the above items "1" to "8" may include, for example, the following configuration. The peripheral surface comprises a first region and a second region.

[0022] Hereinafter, an embodiment of the present disclosure (hereinafter, may be abbreviated as "the present embodiment") will be described. However, the present embodiment does not limit the technical scope of the present disclosure. The present embodiment is illustrative in all respects. The present embodiment is non-restrictive. The technical scope of the present disclosure includes all modifications within the meaning and scope equivalent to the description of the claims. For example, it is also originally intended that any configuration may be extracted from the present embodiment and arbitrarily combined. [Brief description of the drawings]

[0023] [Figure 1] FIG. 2 is a schematic perspective view showing an example of a storage cell according to the present embodiment. [Diagram 2] 1 is a first schematic cross-sectional view showing an example of a storage cell in the present embodiment. [Diagram 3] FIG. 2 is a schematic diagram showing an example of an electrode body in the present embodiment. [Figure 4] 4 is a second schematic cross-sectional view showing an example of a storage cell in the present embodiment. FIG. [Diagram 5] FIG. 2 is a schematic cross-sectional view showing an example of an electrode body in the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] 1. Explanation of terms "Comprise," "include," "have," and variations thereof are open-ended terms. Open-ended terms may or may not include additional elements in addition to the required elements. "Consisting of" is a closed term. However, even a configuration expressed in closed terminology may include additional elements that are normally associated with the impurities or that are unrelated to the disclosed technology. "Consisting essentially of..." is a semi-closed term. Semi-closed terminology allows the addition of elements that do not substantially affect the basic and novel characteristics of the disclosed technology.

[0025] Geometric terms should not be interpreted in a strict sense. Examples of geometric terms include "parallel," "perpendicular," and the like. For example, "parallel" may deviate slightly from the strict meaning of "parallel." Geometric terms may include, for example, tolerances, errors, and the like in design, work, and manufacturing. The dimensional relationships in each figure may not match the actual dimensional relationships. The dimensional relationships in each figure may be changed to help the reader understand. For example, the length, width, thickness, and the like may be changed. Furthermore, some configurations may be omitted.

[0026] Numerical ranges such as "m to n%" include upper and lower limits unless otherwise specified. That is, "m to n%" indicates a numerical range of "m% or more and n% or less". Also, "m% or more and n% or less" includes "more than m% and less than n%". "More than" and "less than" are represented by an inequality sign with an equal sign "≦". "More than" and "less than" are represented by an inequality sign without an equal sign "<". A numerical value arbitrarily selected from within the numerical range may be set as a new upper or lower limit. For example, a new numerical range may be set by arbitrarily combining a numerical value within the numerical range with a numerical value described in another part, table, figure, etc. of this specification.

[0027] All numerical values ​​are modified by the term "about". The term "about" may mean, for example, ±5%, ±3%, ±1%, etc. All numerical values ​​may be approximations that may vary depending on the application of the disclosed technology. All numerical values ​​may be expressed in significant figures. Measurements may be average values ​​of multiple measurements unless otherwise specified. The number of measurements may be three or more, five or more, or ten or more. In general, the more measurements are made, the more reliable the average value is expected to be. Measurements may be rounded off based on the number of significant figures. Measurements may include errors associated with, for example, the detection limit of the measurement device.

[0028] 2. Energy storage cells FIG. 1 is a schematic perspective view showing an example of a storage cell in this embodiment. The storage cell 1 may have, for example, a height direction, a width direction, and a thickness direction. The height direction, width direction, and thickness direction are perpendicular to each other. The "height direction" is the H direction in FIG. 1, etc. The "width direction" is the W direction in FIG. 1, etc. The "thickness direction" is the D direction in FIG. 1, etc. The height direction may be parallel to the vertical direction, for example. The width direction and the thickness direction may be parallel to the horizontal direction, for example. "Height" refers to the dimension in the height direction. "Width" refers to the dimension in the width direction. "Thickness" refers to the dimension in the thickness direction, or the thickness of an object.

[0029] Fig. 2 is a first schematic cross-sectional view showing an example of a storage cell in this embodiment. Fig. 2 shows a cross section perpendicular to the thickness direction. The storage cell 1 includes a case 200, an electrode body 100, an insulating film 101, and an electrolyte solution (not shown). The electrolyte solution is a liquid electrolyte. The electrolyte solution may include, for example, an organic solvent and a lithium salt.

[0030] 3. Electrode body, insulating film The electrode body 100 may have, for example, a cubic outer shape. The electrode body 100 may have, for example, a rectangular parallelepiped outer shape. The electrode body 100 may have, for example, a flattened rectangular parallelepiped shape.

[0031] The "first aspect ratio" refers to the ratio of the width to the height in the electrode body 100. The first aspect ratio may be, for example, 1 or more, 1.5 or more, 2 or more, 2.5 or more, 3 or more, 5 or more, or 10 or more. The first aspect ratio may be, for example, 10 or less, 5 or less, 3 or less, 2.5 or less, 2 or less, or 1.5 or less. The "second aspect ratio" refers to the ratio of the thickness to the height in the electrode body 100. The second aspect ratio may be, for example, 0.1 or more, 0.2 or more, 0.3 or more, 0.5 or more, or 1 or more. The second aspect ratio may be, for example, 1 or less, 0.5 or less, 0.3 or less, or 0.2 or less.

[0032] FIG. 3 is a schematic diagram showing an example of an electrode body in this embodiment. The electrode body 100 has an upper surface 100a, a lower surface 100b, and a peripheral surface 100c. The upper surface 100a, the lower surface 100b, and the peripheral surface 100c may be flat surfaces or may be uneven surfaces. The upper surface 100a may be parallel to the lower surface 100b. The peripheral surface 100c connects the upper surface 100a and the lower surface 100b. The peripheral surface 100c may include four planes. Each plane may be rectangular.

[0033] Fig. 4 is a second schematic cross-sectional view showing an example of a storage cell in this embodiment. Fig. 4 shows a cross section perpendicular to the height direction. The peripheral surface 100c includes a first region R1 and a second region R2. The peripheral surface 100c may be composed of the first region R1 and the second region R2.

[0034] The first region R1 is covered with an insulating film 101. The insulating film 101 may be attached to the first region R1. The insulating film 101 may be adhered to the first region R1. For example, the insulating film 101 may be adhered to the first region R1 by an adhesive. The first region R1 may be a continuous region. The first region R1 may be divided into a plurality of portions.

[0035] The second region R2 is not covered by the insulating film 101. The second region R2 may be a continuous region. The second region R2 may be divided into a plurality of portions. The second region R2 is sandwiched between the first region R1. In the circumferential direction of the peripheral surface 100c, the second region R2 may be sandwiched, for example, between the beginning end of the first region R1 and the end end of the first region R1. The second region R2 extends in the height direction. The second region R2 extends from the upper surface 100a to the lower surface 100b.

[0036] The second region R2 has an area smaller than that of the first region R1. The ratio of the area of ​​the second region R2 to the area of ​​the first region R1 may be, for example, 0.5 or less, 0.4 or less, 0.3 or less, 0.2 or less, 0.1 or less, 0.05 or less, 0.03 or less, or 0.01 or less. The ratio of the area of ​​the second region R2 to the area of ​​the first region R1 may be, for example, 0.001 or more, 0.005 or more, 0.01 or more, 0.05 or more, or 0.1 or more.

[0037] In addition, when the first region R1 is divided into a plurality of parts, the total area of ​​all the parts is regarded as the area of ​​the first region R1. The same applies to the second region R2.

[0038] The insulating film 101 has a length direction and a width direction. The width direction is perpendicular to the length direction. The width direction of the insulating film 101 is parallel to the height direction. The insulating film 101 may be, for example, strip-shaped. The length dimension of the insulating film 101 may be shorter than the perimeter of the peripheral surface 100c. A continuous first region R1 can be formed by wrapping the insulating film 101, which is shorter than the perimeter, around the peripheral surface 100c.

[0039] The thickness of the insulating film 101 may be, for example, 1 μm or more, 5 μm or more, 10 μm or more, 50 μm or more, 100 μm or more, 500 μm or more, or 1 mm or more. The thickness of the insulating film 101 may be, for example, 2 mm or less, 1 mm or less, 500 μm or less, 100 μm or less, 50 μm or less, 10 μm or less, or 5 μm or less. The thickness of the insulating film 101 may be uniform or may vary locally. A single sheet of the insulating film 101 may be used. A plurality of insulating films 101 may be used. For example, a plurality of insulating films 101 may be laminated. For example, a plurality of insulating films 101 may be joined together.

[0040] Insulating film 101 has electrical insulation properties. Insulating film 101 may contain any material as long as it has electrical insulation properties. Insulating film 101 may be made of, for example, a resin. Insulating film 101 may contain, for example, at least one selected from the group consisting of polypropylene (PP), polyimide (PI), polyethylene (PE), polyethylene terephthalate (PET), and polyphenylene sulfide (PPS).

[0041] The energy storage cell 1 may further include a first insulating member 102. The first insulating member 102 may have an area larger than that of the second region R2. The ratio of the area of ​​the first insulating member 102 to the area of ​​the second region R2 may be, for example, any of 1.01 or more, 1.1 or more, 1.2 or more, 1.5 or more, or 2 or more. The ratio of the area of ​​the first insulating member 102 to the area of ​​the second region R2 may be, for example, any of 2.5 or less, 2.0 or less, or 1.5 or less.

[0042] The first insulating member 102 may be disposed on, for example, a surface of the case 200. For example, the first insulating member 102 may be disposed in a position facing the second region R2 in the case 200. The first insulating member 102 may contain, for example, an insulating paint or the like. For example, an insulating paint may be applied to the position facing the second region R2 in the case 200. The insulating paint may contain, for example, a ceramic powder, a resin powder, a resin film, or the like.

[0043] The first insulating member 102 may include, for example, an insulating tape. The insulating tape may extend, for example, across the second region R2 to bridge the first regions R1. The insulating tape may extend, for example, to connect the start end of the first region R1 to the end end of the first region R1. The insulating tape may be attached to the insulating film 101 or to the case 200. The insulating tape may be, for example, thinner than the insulating film 101. The ratio of the thickness of the insulating tape to the thickness of the insulating film 101 may be, for example, 1 or less, 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, or 0.5 or less. The ratio of the thickness of the insulating tape to the thickness of the insulating film 101 may be, for example, 0.1 or more, 0.2 or more, 0.3 or more, 0.4 or more, or 0.5 or more.

[0044] The insulating tape may include, for example, a base layer and an adhesive layer. The adhesive layer is laminated on the base layer. The base layer may include, for example, the same material as the insulating film 101. The base layer may have a thickness of, for example, 1 to 100 μm. The adhesive layer may include, for example, at least one selected from the group consisting of an acrylic adhesive, a silicone adhesive, a urethane adhesive, and a rubber adhesive.

[0045] 4.Laminated structure The electrode body may have any laminated structure. The electrode body may be, for example, a wound type. The electrode body may be, for example, a laminated type.

[0046] FIG. 5 is a schematic cross-sectional view showing an example of an electrode assembly in this embodiment. The electrode assembly 100 in FIG. 5 is a laminated type. The electrode assembly 100 includes one or more first electrodes 110, one or more second electrodes 120, and one or more separators 130. The first electrodes 110 and the second electrodes 120 are alternately laminated in the thickness direction. That is, the thickness direction of the storage cell 1 is parallel to the lamination direction of the first electrodes 110 and the second electrodes 120. The number of the first electrodes 110 and the second electrodes 120 may be any of 2 or more, 5 or more, 10 or more, 50 or more, or 100 or more. The number of the first electrodes 110 and the second electrodes 120 may be any of 200 or less, 100 or less, 50 or less, 10 or less, or 5 or less.

[0047] The second electrode 120 has a different polarity than the first electrode 110. For example, the first electrode 110 may be a positive electrode and the second electrode 120 may be a negative electrode. For example, the first electrode 110 may be a negative electrode and the second electrode 120 may be a positive electrode.

[0048] The first electrode 110 may include, for example, a first current collector 112 and a first active material layer 114. The first current collector 112 may include, for example, a metal foil or the like. The metal foil may include, for example, Al, Cu, Ni, Ti, Fe, or the like. The first active material layer 114 is disposed on a surface of the first current collector 112. The first active material layer 114 may be disposed on only one side of the first current collector 112. The first active material layer 114 may be disposed on both sides of the first current collector 112. The first active material layer 114 includes a positive electrode active material or a negative electrode active material. The positive electrode active material may include, for example, a lithium nickel composite oxide, or the like. The negative electrode active material may include, for example, graphite, SiO, Si, or the like.

[0049] The second electrode 120 may include, for example, a second current collector 122 and a second active material layer 124. The second current collector 122 may include, for example, a metal foil or the like. The second active material layer 124 is disposed on a surface of the second current collector 122. The second active material layer 124 may be disposed on only one side of the second current collector 122. The second active material layer 124 may be disposed on both sides of the second current collector 122. The second active material layer 124 includes a positive electrode active material or a negative electrode active material. The second active material layer 124 may have the same area as the first active material layer 114, or may have a different area. For example, the area of ​​the second active material layer 124 may be larger than the area of ​​the first active material layer 114. The ratio of the area of ​​the second active material layer 124 to the area of ​​the first active material layer 114 may be, for example, any of 1.01 or more, 1.05 or more, or 1.1 or more. The ratio of the area of ​​the second active material layer 124 to the area of ​​the first active material layer 114 may be, for example, any of 1.1 or less, 1.05 or less, or 1.01 or less.

[0050] The separator 130 has electrical insulation properties. The separator 130 is porous. The separator 130 may include, for example, a microporous film made of polyolefin. The thickness of the separator 130 may be, for example, 5 to 50 μm, 5 to 30 μm, or 5 to 15 μm. The separator 130 separates the first electrode 110 from the second electrode 120. The separator 130 may be, for example, two or more sheets. For example, the separator 130 may be inserted between each of the first electrode 110 and the second electrode 120.

[0051] Separator 130 may be, for example, a single sheet. For example, separator 130 may include zigzag fold portion 135. Separator 130 is folded in a zigzag shape at zigzag fold portion 135. The zigzag shape may also be expressed as, for example, a "bellows shape" or an "accordion shape."

[0052] The zigzag fold portion 135 includes a flat portion 131 and a folded portion 132. In the flat portion 131, the separator 130 extends in a flat shape. In the folded portion 132, the separator 130 is folded. The folded portion 132 is disposed at both ends in the height direction. The separator 130 is folded so as to alternately sandwich the first electrode 110 or the second electrode 120. The flat portion 131 sandwiches the first electrode 110 or the second electrode 120. The separator 130 may further include, for example, an outer peripheral portion 136. The outer peripheral portion 136 may be wound so as to wrap the zigzag fold portion 135. Note that the zigzag fold portion may be formed by folding the separator 130 at both ends in the width direction.

[0053] 5. Case The case 200 houses the electrolyte and the electrode assembly 100. The case 200 may be sealed. The case 200 may be sealed. The case 200 may include, for example, a can 210 and a lid 220. The can 210 has an opening. The opening opens in the height direction. The opening may open, for example, vertically upward. The can 210 may be made of metal, for example. The can 210 may include, for example, Al or the like. The can 210 may include, for example, a bottom wall 212 and a peripheral wall 214. The bottom wall 212 may be, for example, flat. The planar shape of the bottom wall 212 may be, for example, rectangular. The peripheral wall 214 stands up from the bottom wall 212. The peripheral wall 214 may be, for example, a rectangular tube. The width of the peripheral wall 214 may be greater than the thickness of the peripheral wall 214. The height of the peripheral wall 214 may be greater than the thickness of the peripheral wall 214. Note that the "thickness of the peripheral wall 214" here refers to the outer dimension of the case 200 in the thickness direction.

[0054] The lid 220 closes the opening of the can 210. The lid 220 may be welded to the peripheral wall 214. The lid 220 may be, for example, flat. The lid 220 may be made of metal. The lid 220 may include, for example, Al, etc. The lid 220 may include, for example, a pressure release valve 222, a sealing member 224, etc.

[0055] The pressure release valve 222 may be disposed, for example, near the center of the lid 220. The pressure release valve 222 releases the internal pressure of the case 200. When the internal pressure reaches or exceeds a set value, the pressure release valve 222 can be opened. The sealing member 224 seals the liquid injection hole 221. An electrolyte can be injected from the liquid injection hole 221.

[0056] The inner surface of the lid 220 faces the upper surface 100a of the electrode body 100. That is, the case 200 has a liquid inlet 221 on the surface facing the upper surface 100a. The liquid inlet 221 may have a specific positional relationship with the second region R2. The second region R2 may be disposed below the liquid inlet 221. For example, an angle between a straight line connecting the second region R2 and the liquid inlet 221 and the height direction may be 60° or less. The angle may be, for example, 45° or less, 30° or less, 15° or less, 5° or less, 3° or less, or 1° or less. The second region R2 may be disposed, for example, directly below the liquid inlet 221. For example, the position of the liquid inlet 221 may coincide with the position of the second region R2 in the width direction.

[0057] A pair of external terminals 300 are fixed to the lid 220. The external terminals 300 are connected to the first electrode 110 or the second electrode 120. The external terminals 300 may be made of metal, for example. The external terminals may contain Al, Cu, Ni, or the like. The external terminals 300 may have an outer shape of a rectangular parallelepiped, for example. The external terminals 300 may be connected to a bus bar (not shown).

[0058] A pair of connecting members 400 connect the electrode tabs to the external terminals 300. The electrode tabs refer to the first electrode tab 116 or the second electrode tab 126. The two connecting members 400 may have substantially the same structure.

[0059] The connecting member 400 may include, for example, a current collecting tab 410, a sub-tab 420, and a connecting pin 430. The current collecting tab 410 includes a side portion 412 and an upper portion 414. The side portion 412 is located on a side of the electrode body 100 in the width direction. The upper portion 414 is located above the electrode body 100. The upper portion 414 extends from an upper end of the side portion 412 toward the inside in the width direction.

[0060] The sub-tab 420 connects the electrode tabs to the current collecting tab 410. The sub-tab 420 may include a first end 422 and a second end 424. The first end 422 is connected to the electrode tabs. The second end 424 is connected to the side portion 412.

[0061] The connecting pin 430 connects the current collecting tab 410 to the external terminal 300. The connecting pin 430 connects the upper portion 414 to the external terminal 300. For example, a lower end of the connecting pin 430 may be inserted into a through hole provided in the upper portion 414.

[0062] The second insulating member 500 insulates the case 200 from the connecting member 400. The second insulating member 500 may include a first portion 510, a second portion 520, a third portion 530, and a fourth portion 540, for example.

[0063] The first part 510 is fixed to the upper surface of the lid 220. The first part 510 is disposed between the lid 220 and the external terminal 300. The second part 520 is fixed to the lower surface of the lid 220. The second part 520 is disposed between the lid 220 and the upper part 414. The second part 520 is disposed between the lid 220 and a lower part of the connecting pin 430. The third part 530 is disposed between the connecting pin 430 and the lid 220. The third part 530 is cylindrical. The third part 530 surrounds the connecting pin 430. The first part 510, the second part 520 and the third part 530 are provided with through holes. The connecting pin 430 is inserted through the through holes.

[0064] The fourth part 540 is plate-shaped. It is fixed to the lower surface of the upper part 414. The fourth part 540 is disposed above the electrode body 100. In the fourth part 540, a through hole is provided below the pressure release valve 222. In the fourth part 540, a through hole is also provided below the liquid injection hole 221. [Explanation of symbols]

[0065] 1 Energy storage cell, 100 Electrode body, 100a Upper surface, 100b Lower surface, 100c Peripheral surface, 101 Insulating film, 102 First insulating member, 110 First electrode, 112 First current collector, 114 First active material layer, 116 First electrode tab, 120 Second electrode, 122 Second current collector, 124 Second active material layer, 126 Second electrode tab, 130 Separator, 131 Planar portion, 132 Folded portion, 135 Zigzag portion, 136 Outer periphery, 200 Case, 210 Can, 212 Bottom wall, 214 Peripheral wall, 220 Lid, 221 Injection hole, 222 Pressure release valve, 224 Sealing member, 300 External terminal, 400 Connecting member, 410 Current collecting tab, 412 Side portion, 414 Upper portion, 420 subtab, 422 first end, 424 second end, 430 connecting pin, 500 second insulating member, 510 first portion, 520 second portion, 530 third portion, 540 fourth portion, R1 first region, R2 second region.

Claims

1. The battery includes a case, an electrode body, an insulating film, and an electrolyte. the case accommodates the electrode body, the insulating film, and the electrolyte, The electrode body has an upper surface, a lower surface and a peripheral surface, the case has a liquid inlet provided on a surface opposite to the top surface, the peripheral surface connects the upper surface and the lower surface, the peripheral surface includes a first region and a second region; the first region is covered with the insulating film, The second region is not covered with the insulating film, the second region extends from the upper surface to the lower surface; and The second region has a smaller area than the first region. Energy storage cell.

2. Further comprising an insulating member; The insulating member is disposed in the case at a position facing the second region. The storage cell according to claim 1 .

3. The second region is disposed below the liquid injection hole. The storage cell according to claim 1 .

4. Further comprising an insulating tape; The second region is sandwiched between the first regions in a circumferential direction of the circumferential surface, and The insulating tape extends across the second region so as to bridge the first regions. The storage cell according to claim 1 .

5. The insulating film is in a strip shape. The storage cell according to claim 1 .

6. The insulating film is wrapped around the peripheral surface. The storage cell according to claim 1 .

7. the insulating film has a length direction and a width direction, The width direction is perpendicular to the length direction, and The dimension in the length direction is shorter than the circumferential length of the peripheral surface. The storage cell according to claim 1 .

8. The electrode body has a cubic outer shape, and The electrode body is a laminated type. The storage cell according to claim 1 .

9. The peripheral surface is composed of the first region and the second region. The storage cell according to any one of claims 1 to 8.

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