Power storage cell

Abstract

To suppress a short circuit in an internal part of a cell case 20.SOLUTION: In a power storage cell 1 based on the present disclosure, a winding electrode body 10 contains: a first electrode 11P; and a second electrode 11N. A first collector member 30 is connected to the first electrode 11P. A second collector member 40 is connected to the second electrode 11N. A lid 22 contains: a first external terminal 221P; and a second external terminal 221N. The first external terminal 221P is arranged so as to be overlapped with a radial direction center of the winding electrode body 10 in view of a shaft direction Z. The second external terminal 221N is fixed to a case main body 21. The first collector member 30 is connected to the first external terminal 221P. The second collector member 40 is arranged between the case main body 21 and the second external terminal 221N. The second collector member 40 is connected to the second external terminal 221N so as to be fixed to the case main body 21 with the second external terminal 221N.SELECTED DRAWING: Figure 2

Description

[Technical field]

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

[0002] Patent Document 1 discloses a conventional non-aqueous electrolyte secondary battery as a storage cell. In this non-aqueous electrolyte secondary battery, a negative electrode and a positive electrode are wound with a porous separator interposed therebetween and inserted into a cylindrical container. Leads are taken out from the positive electrode and the negative electrode. The cylindrical container is made of stainless steel. A container lid is welded to the opening of the container at its periphery. A positive electrode terminal and a negative electrode terminal are provided on a part of the container lid. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 3322321 Summary of the Invention [Problem to be solved by the invention]

[0004] When both the positive and negative terminals are provided on the lid, as in the case of the storage cell disclosed in Patent Document 1, the positive and negative leads in the container are relatively close to each other, which may cause the leads to come into contact with each other and cause a short circuit, for example.

[0005] The present disclosure has been made in consideration of the above problems, and has an object to provide an energy storage cell that can suppress short circuits inside the cell casing. [Means for solving the problem]

[0006] A power storage cell according to a first aspect of the present disclosure includes a wound electrode body, a cell case, a first current collecting member, and a second current collecting member. The wound electrode body includes a first electrode and a second electrode. The cell case houses the wound electrode body. The first current collecting member is connected to the first electrode. The second current collecting member is connected to the second electrode. The cell case includes a case body and a lid. The case body has an opening that opens on one side in the axial direction of the wound electrode body when viewed from the wound electrode body. The lid closes the opening of the case body. The lid includes a first external terminal and a second external terminal. The first external terminal is arranged so as to overlap with a radial center of the wound electrode body when viewed from the axial direction. The second external terminal is fixed to the case body. The first current collecting member is arranged on the one side in the axial direction of the wound electrode body. The first current collecting member is connected to the first external terminal. The second current collecting member is disposed on the one side in the axial direction of the wound electrode body. The second current collecting member is disposed between the case body and the second external terminal. The second current collecting member is joined to the second external terminal by being fixed to the case body together with the second external terminal.

[0007] According to the above configuration, the second external terminal and the second current collecting member are joined to each other at a position relatively distant from the first current collecting member connected to the first external terminal. This makes it possible to suppress a short circuit between the first current collecting member and the second current collecting member. Therefore, according to the above configuration, it is possible to provide a storage cell in which a short circuit inside the cell casing is suppressed.

[0008] A storage cell according to a second aspect of the present disclosure includes a wound electrode body, a cell case, a first current collecting member, and a second current collecting member. The wound electrode body includes a first electrode and a second electrode. The cell case houses the wound electrode body. The first current collecting member is connected to the first electrode. The second current collecting member is connected to the second electrode. The cell case includes a case body and a lid. The case body is conductive and has an opening that opens on one side in the axial direction of the wound electrode body when viewed from the wound electrode body. The lid closes the opening of the case body. The lid includes a first external terminal and a second external terminal. The first external terminal is arranged so as to overlap with the radial center of the wound electrode body when viewed from the axial direction. The second external terminal is directly joined to the case body. The first current collecting member is arranged on the one side in the axial direction of the wound electrode body. The first current collecting member is connected to the first external terminal. The second current collecting member is disposed on the other side of the wound electrode body in the axial direction. The second current collecting member is directly connected to the case body.

[0009] According to the above configuration, the second external terminal and the second current collecting member are electrically connected to each other via the case body at a position relatively distant from the first current collecting member connected to the first external terminal. This makes it possible to suppress a short circuit between the first current collecting member and the second current collecting member. Therefore, according to the above configuration, it is possible to provide a storage cell in which a short circuit inside the cell case is suppressed. Effect of the Invention

[0010] According to the present disclosure, short circuits inside the cell casing can be suppressed. [Brief description of the drawings]

[0011] [Figure 1] 1 is a perspective view showing a storage cell according to a first embodiment. [Diagram 2] 2 is a cross-sectional view of the storage cell of FIG. 1 as viewed in the direction of the arrows along line II-II. [Diagram 3] FIG. 4 is a cross-sectional view showing a storage cell according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, a storage cell according to each embodiment of the present disclosure will be described with reference to the drawings. The same or corresponding parts in the drawings are denoted by the same reference characters, and description thereof will not be repeated.

[0013] (Embodiment 1) Fig. 1 is a perspective view showing a storage cell according to embodiment 1. Fig. 2 is a cross-sectional view of the storage cell of Fig. 1 as viewed in the direction of the arrows along line II-II.

[0014] 1 and 2, the energy storage cell 1 according to the first embodiment is a cylindrical battery. The energy storage cell 1 includes a wound electrode body 10, a cell case 20, a first current collecting member 30, and a second current collecting member 40.

[0015] First, a description will be given of the wound electrode body 10. As shown in Fig. 2, the wound electrode body 10 includes a positive electrode 11P, a negative electrode 11N, and a separator 12. In the wound electrode body 10, the positive electrode 11P, the negative electrode 11N, and the separator 12 are wound so as to surround the periphery of a winding axis α.

[0016] In the first embodiment, the first electrode in the present disclosure is exemplified by a positive electrode 11P. In the first embodiment, the second electrode in the present disclosure is exemplified by a negative electrode 11N. However, the first electrode may be a negative electrode. The second electrode may be a positive electrode.

[0017] Positive electrode 11P and negative electrode 11N have a sheet-like outer shape. Wound electrode body 10 is composed of an electrode plate group in which positive electrode 11P and negative electrode 11N are wound with separator 12 interposed therebetween.

[0018] Separator 12 is provided between positive electrode 11P and negative electrode 11N. Separator 12 separates positive electrode 11P from negative electrode 11N while allowing ions (e.g., lithium ions) to move between positive electrode 11P (positive electrode active material) and negative electrode 11N (negative electrode active material).

[0019] Positive electrode 11P includes positive electrode current collector foil 111P and positive electrode mixture layer 112P. Positive electrode current collector foil 111P is made of, for example, aluminum.

[0020] The positive electrode mixture layer 112P is applied to both radial surfaces of the positive electrode current collector foil 111P. The positive electrode mixture layer 112P is in close contact with the separator 12. The positive electrode mixture layer 112P is formed by applying a positive electrode slurry to the surface of the positive electrode current collector foil 111P and drying the applied positive electrode slurry. The positive electrode slurry is prepared by kneading the materials of the positive electrode mixture layer 112P (such as a positive electrode active material and a binder) with a solvent. The thickness of the positive electrode mixture layer 112P is, for example, 0.1 μm or more and 1000 μm or less.

[0021] Negative electrode 11N includes negative electrode current collector foil 111N and negative electrode mixture layer 112N. Negative electrode current collector foil 111N is made of, for example, copper.

[0022] The negative electrode mixture layer 112N is applied to both radial surfaces of the negative electrode current collector foil 111N. The negative electrode mixture layer 112N is in close contact with the separator 12. The negative electrode mixture layer 112N is formed by applying a negative electrode slurry to the surface of the negative electrode current collector foil 111N and drying the coating. The negative electrode slurry is prepared by kneading the materials of the negative electrode mixture layer 112N (such as a negative electrode active material and a binder) and a solvent. The thickness of the negative electrode mixture layer 112N is, for example, 0.1 μm or more and 1000 μm or less.

[0023] Next, a description will be given of the cell case 20. As shown in Figures 1 and 2, the cell case 20 houses the wound electrode body 10. The cell case 20 includes a case body 21 and a lid 22.

[0024] When viewed from the wound electrode body 10, the case body 21 has an opening 211 that opens on one side (first direction Z1 side) in the axial direction Z of the wound electrode body 10. Specifically, the opening 211 opens on the first direction Z1 side of the case body 21. The case body 21 has a cylindrical outer shape with a bottom.

[0025] The case body 21 further includes a crimped portion 212 formed by crimping an end portion on one side (the side in the first direction Z1) of the wound electrode body 10. The crimped portion 212 extends along the opening 211 in an annular shape.

[0026] The case body 21 further includes a cylindrical wall portion 213 , a bottom portion 214 , and a sealing layer 215 .

[0027] The cylindrical wall portion 213 is provided so as to cover the outer circumferential side of the wound electrode body 10. The cylindrical wall portion 213 covers the entire outer circumferential side of the wound electrode body 10. The cylindrical wall portion 213 has a cylindrical shape. The cylindrical wall portion 213 may have a rectangular cylindrical outer shape. The cylindrical wall portion 213 is located on the second direction Z2 side in the axial direction Z as viewed from the crimped portion 212. The cylindrical wall portion 213 is molded integrally with the crimped portion 212.

[0028] The bottom portion 214 is disposed on the second direction Z2 side along the axial direction Z when viewed from the wound electrode body 10. The bottom portion 214 is connected to an end portion of the cylindrical wall portion 213 on the second direction Z2 side. In this embodiment, the bottom portion 214 is integrally formed with the cylindrical wall portion 213. The bottom portion 214 may be formed as a separate member from the cylindrical wall portion 213. At this time, the outer peripheral edge of the bottom portion 214 may be joined to the cylindrical wall portion 213 by laser welding or the like.

[0029] A through hole 214h is formed in the bottom 214. The through hole 214h may be provided for injecting an electrolyte (not shown) to be contained in the cell casing 20. A sealing plug 216 is inserted into the through hole 214h of the bottom 214. This fixes the sealing plug 216 to the bottom 214. The sealing plug 216 and the through hole 214h can function as a pressure relief valve for releasing the pressure inside the cell casing 20 when the pressure inside the cell casing 20 becomes excessively high.

[0030] The crimping portion 212, the cylindrical wall portion 213, and the bottom portion 214 are electrically conductive. The crimping portion 212, the cylindrical wall portion 213, and the bottom portion 214 are made of aluminum or an aluminum alloy, copper, stainless steel, or the like.

[0031] The seal layer 215 is disposed radially inside the crimped portion 212. In this embodiment, the seal layer 215 forms the opening 211. The seal layer 215 extends along the crimped portion 212. The seal layer 215 has an annular outer shape. The seal layer 215 has electrical insulation properties.

[0032] The lid 22 closes the opening 211 of the case body 21. The lid 22 includes a positive external terminal 221P, a negative external terminal 221N, and an insulating member 222. In the first embodiment, the positive external terminal 221P is exemplified as the first external terminal in the present disclosure. In the first embodiment, the negative external terminal 221N is exemplified as the second external terminal in the present disclosure. However, the first external terminal may be a negative external terminal, and the second external terminal may be a positive external terminal.

[0033] The positive electrode external terminal 221P is disposed so as to overlap with the radial center of the wound electrode body 10 when viewed from the axial direction Z. The positive electrode external terminal 221P is formed from, for example, aluminum, copper, or stainless steel.

[0034] The positive electrode external terminal 221P is disposed on the first direction Z1 side of the wound electrode body 10. The positive electrode external terminal 221P includes a disk portion 221PA and a rivet portion 221PB.

[0035] The disk portion 221PA is exposed to the outside. The disk portion 221PA is located on the opposite side of the wound electrode body 10 from the negative external terminal 221N.

[0036] The rivet portion 221PB is connected to the disk portion 221PA. The rivet portion 221PB extends from the center of the disk portion 221PA when viewed from the axial direction Z. The rivet portion 221PB is located approximately on the winding axis α of the wound electrode body 10. The rivet portion 221PB extends toward the second direction Z2 when viewed from the disk portion 221PA.

[0037] The negative external terminal 221N has a plate-like outer shape. Specifically, the negative external terminal 221N has a substantially disk-like outer shape. The negative external terminal 221N is provided so as to be perpendicular to the axial direction Z. A through hole 221Nh is provided in the negative external terminal 221N. Therefore, the negative external terminal 221N has an annular outer shape when viewed from the axial direction Z. The rivet portion 221PB of the positive external terminal 221P is inserted into the through hole 221Nh. As a result, the rivet portion 221PB extends into the inside of the cell case 20.

[0038] The negative electrode external terminal 221N is made of aluminum or an aluminum alloy, copper, or stainless steel.

[0039] The negative external terminal 221N is fixed to the case body 21. The manner in which the negative external terminal 221N is fixed to the case body will be described later in detail.

[0040] The first current collecting member 30 is connected to the positive electrode 11P. Specifically, the first current collecting member 30 is provided so as to protrude from the positive electrode current collecting foil 111P of the positive electrode 11P to one side in the axial direction Z (the first direction Z1 side). Therefore, the first current collecting member 30 is disposed on the one side in the axial direction Z of the wound electrode body 10 (the first direction Z1 side).

[0041] The first current collecting member 30 is connected to the positive external terminal 221P. Specifically, the first current collecting member 30 is joined to the rivet portion 221PB of the positive external terminal 221P by welding.

[0042] The first current collecting member 30 has a tab lead-like outer shape, but the shape of the first current collecting member 30 is not particularly limited. The first current collecting member 30 may be a plate-like member extending in a planar direction perpendicular to the axial direction Z. The first current collecting member 30 is conductive. The material constituting the first current collecting member 30 is not particularly limited. The first current collecting member 30 may include a metal contained in the positive current collecting foil 111P or the positive external terminal 221P.

[0043] The second current collecting member 40 is connected to the negative electrode 11N. Specifically, the second current collecting member 40 is provided so as to protrude from the negative electrode current collecting foil 111N of the negative electrode 11N to one side in the axial direction Z (the first direction Z1 side). Therefore, the second current collecting member 40 is disposed on the one side in the axial direction Z of the wound electrode body 10 (the first direction Z1 side).

[0044] The second current collecting member 40 is disposed between the case body 21 and the negative external terminal 221N. The second current collecting member 40 is joined to the negative external terminal 221N by being fixed to the case body 21 together with the negative external terminal 221N. Specifically, the second current collecting member 40 is fixed to the crimping portion 212 together with the negative external terminal 221N. In other words, the second current collecting member 40 is fixed to the case body 21 together with the negative external terminal 221N by being crimped.

[0045] More specifically, the seal layer 215 is disposed between the negative external terminal 221N and the second current collecting member 40, and the crimped portion 212. The seal layer 215 is provided so as to cover the outer peripheral edge of the negative external terminal 221N and the end of the second current collecting member 40 on the opposite side to the negative electrode 11N side.

[0046] The second current collecting member 40 has a tab lead-like outer shape, but the shape of the second current collecting member 40 is not particularly limited. The second current collecting member 40 may be a plate-like member extending in a planar direction perpendicular to the axial direction Z. The second current collecting member 40 is conductive. The material constituting the second current collecting member 40 is not particularly limited. The second current collecting member 40 may include a metal contained in the negative electrode current collecting foil 111N or the negative electrode external terminal 221N.

[0047] The energy storage cell 1 according to this embodiment may further include a first inner insulating member 50, a second inner insulating member 60, and a third inner insulating member .

[0048] The first internal insulating member 50 is provided on the inner surface of the negative electrode external terminal 221N. The first internal insulating member 50 is provided between the negative electrode external terminal 221N and the first current collecting member 30. The first internal insulating member 50 is provided to insulate the negative electrode external terminal 221N from the first current collecting member 30.

[0049] The second inner insulating member 60 is housed in the cell case 20. The second inner insulating member 60 is provided on the first direction Z1 side of the wound electrode body 10. In the axial direction Z, the second inner insulating member 60 is disposed between the wound electrode body 10 and the crimped portion 212. A first through hole 61 and a second through hole 62 are formed in the second inner insulating member 60. The first through hole 61 is inserted into the first through hole 61. The second current collecting member 40 is inserted into the second through hole 62.

[0050] The third internal insulating member 70 is housed in the cell case 20. The third internal insulating member 70 is provided on the second direction Z2 side of the wound electrode body 10. The third internal insulating member 70 is provided between the bottom portion 214 and the wound electrode body 10. The third internal insulating member 70 is provided to insulate the bottom portion 214 from the wound electrode body 10.

[0051] As described above, the energy storage cell 1 according to the first embodiment of the present disclosure includes the wound electrode body 10, the cell case 20, the first current collecting member 30, and the second current collecting member 40. The wound electrode body 10 includes a positive electrode 11P (first electrode) and a negative electrode 11N (second electrode). The cell case 20 houses the wound electrode body 10. The first current collecting member 30 is connected to the positive electrode 11P. The second current collecting member 40 is connected to the negative electrode 11N. The cell case 20 includes a case body 21 and a lid 22. When viewed from the wound electrode body 10, the case body 21 has an opening 211 that opens on one side of the wound electrode body 10 in the axial direction Z. The lid 22 closes the opening 211 of the case body 21. The lid 22 includes a positive electrode external terminal 221P (first external terminal) and a negative electrode external terminal 221N (second external terminal). The positive electrode external terminal 221P is arranged so as to overlap with the radial center of the wound electrode body 10 when viewed from the axial direction Z. The negative electrode external terminal 221N is fixed to the case body 21. The first current collecting member 30 is arranged on the one side in the axial direction Z of the wound electrode body 10. The first current collecting member 30 is connected to the positive electrode external terminal 221P. The second current collecting member 40 is arranged on the one side in the axial direction Z of the wound electrode body 10. The second current collecting member 40 is arranged between the case body 21 and the negative electrode external terminal 221N. The second current collecting member 40 is joined to the negative electrode external terminal 221N by being fixed to the case body 21 together with the negative electrode external terminal 221N.

[0052] According to the above configuration, the negative external terminal 221N (second external terminal) and the second current collecting member 40 are joined to each other at a position relatively distant from the first current collecting member 30 connected to the positive external terminal 221P (first external terminal). This makes it possible to suppress a short circuit between the first current collecting member 30 and the second current collecting member 40. Therefore, according to the above configuration, it is possible to provide a storage cell 1 in which a short circuit inside the cell casing 20 is suppressed.

[0053] In this embodiment, the case body 21 further includes a crimped portion 212 formed by crimping the end portion on the one side of the wound electrode body 10. The second current collecting member 40 is fixed to the crimped portion 212 together with the negative external terminal 221N (second external terminal).

[0054] When the case body 21 is connected to the lid 22 by welding, there is a possibility that foreign matter may get into the cell case 20. However, with the above configuration, the intrusion of foreign matter into the cell case 20 is suppressed compared to when the case body 21 is connected to the lid 22 by welding. Therefore, with the above configuration, it is possible to provide an energy storage cell 1 in which short circuits inside the cell case 20 are further suppressed.

[0055] In this embodiment, the case body 21 further includes a seal layer 215 that is disposed between the negative external terminal 221N (second external terminal) and the second current collecting member 40, and the crimped portion 212, and has electrical insulation properties.

[0056] According to the above configuration, it is possible to prevent a short circuit, via the case body 21, between the negative electrode external terminal 221N (second external terminal) and the positive electrode 11P (first electrode) or a member electrically connected to the positive electrode 11P.

[0057] (Embodiment 2) Next, a description will be given of a power storage cell according to a second embodiment of the present disclosure. In the second embodiment of the present disclosure, the main difference from the first embodiment of the present disclosure is the configuration related to the second current collecting member. Therefore, the description of the same configuration and effects as those of the first embodiment of the present disclosure will not be repeated.

[0058] Fig. 3 is a cross-sectional view showing a storage cell according to embodiment 2. As shown in Fig. 3, in embodiment 2, the case body 21a does not include the crimped portion and the seal layer shown in embodiment 1. An end of the cylindrical wall portion 213a on the first direction Z1 side forms an opening 211. In this embodiment, the case body 21a is entirely conductive.

[0059] The negative external terminal 221Na is directly joined to the case body 21a. The negative external terminal 221Na is directly joined to the opening 211 of the case body 21a (cylindrical wall portion 213a). The negative external terminal 221Na is joined to the case body 21a by welding. The negative external terminal 221Na is joined to the opening 211 of the case body 21a (cylindrical wall portion 213a) by welding. A welded portion 217 is formed between the negative external terminal 221Na and the case body 21a (cylindrical wall portion 213a).

[0060] The second current collecting member 40a is provided so as to protrude from the negative electrode current collecting foil 111N of the negative electrode 11N to the other side in the axial direction Z (the second direction Z2 side). Therefore, the second current collecting member 40a is disposed on the other side in the axial direction Z of the wound electrode body 10 (the second direction Z2 side).

[0061] The second current collecting member 40a is directly connected to the case body 21a. The second current collecting member 40a may be joined to the case body 21a by welding or the like. The second current collecting member 40a is connected to the bottom 214. The second current collecting member 40a may be connected to the cylindrical wall portion 213a. The second current collecting member 40a may be connected to both the bottom portion 214 and the cylindrical wall portion 213a.

[0062] In this embodiment, the second inner insulating member 60a does not necessarily have to have a second through hole as shown in embodiment 1. On the other hand, the third inner insulating member 70a has a third through hole 71. The second current collecting member 40a is inserted into the third through hole 71.

[0063] As described above, the energy storage cell 1a according to the second embodiment of the present disclosure includes the wound electrode body 10, the cell case 20, the first current collecting member 30, and the second current collecting member 40a. The wound electrode body 10 includes a positive electrode 11P (first electrode) and a negative electrode 11N (second electrode). The cell case 20 houses the wound electrode body 10. The first current collecting member 30 is connected to the positive electrode 11P. The second current collecting member 40a is connected to the negative electrode 11N. The cell case 20 includes a case body 21a and a lid 22. The case body 21a is conductive and has an opening 211 that opens on one side of the wound electrode body 10 in the axial direction Z when viewed from the wound electrode body 10. The lid 22 closes the opening 211 of the case body 21a. The lid 22 includes a positive electrode external terminal 221P (first external terminal) and a negative electrode external terminal 221Na (second external terminal). The positive electrode external terminal 221P is arranged so as to overlap with the radial center of the wound electrode body 10 when viewed from the axial direction Z. The negative electrode external terminal 221Na is directly joined to the case body 21a. The first current collecting member 30 is arranged on the one side in the axial direction Z of the wound electrode body 10. The first current collecting member 30 is connected to the positive electrode external terminal 221P. The second current collecting member 40a is arranged on the other side in the axial direction Z of the wound electrode body 10. The second current collecting member 40a is directly connected to the case body 21a.

[0064] According to the above configuration, the negative external terminal 221Na (second external terminal) and the second current collecting member 40a are electrically connected to each other via the case body 21a at a position relatively distant from the first current collecting member 30 connected to the positive external terminal 221P (first external terminal). This makes it possible to suppress a short circuit between the first current collecting member 30 and the second current collecting member 40a. Therefore, according to the above configuration, it is possible to provide a storage cell 1a in which a short circuit inside the cell case 20 is suppressed.

[0065] In this embodiment, the negative external terminal 221Na (second external terminal) is joined to the case body 21a by welding.

[0066] According to the above configuration, the distance between the wound electrode body 10 and the lid 22 can be reduced compared to when the negative external terminal 221Na (second external terminal) is joined by crimping the case body 21a. Therefore, the energy density of the energy storage cell 1a can be improved.

[0067] In the above description of each embodiment, configurations that can be combined may be combined with each other.

[0068] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present disclosure is defined by the claims, not by the description of the embodiments described above, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0069] 1,1a storage cell, 10 wound electrode body, 11N negative electrode, 111N negative electrode current collector foil, 112N negative electrode composite layer, 11P positive electrode, 111P positive electrode current collector foil, 112P positive electrode composite layer, 12 separator, 20 cell case, 21,21a case body, 211 opening, 212 crimping portion, 213,213a cylindrical wall portion, 214 bottom portion, 215 seal layer, 216 sealing plug, 217 welded portion, 22 lid, 221N,221Na negative electrode external terminal, 221P positive electrode external terminal, 221PA disk portion, 221PB rivet portion, 222 insulating member, 30 first current collector member, 40,40a second current collector member, 50 first internal insulating member, 60,60a Second inner insulating member, 61, first through hole, 62, second through hole, 70, 70a, third inner insulating member, 71, third through hole.

Claims

1. A wound electrode body including a first electrode and a second electrode; a cell case that houses the wound electrode body; a first current collecting member connected to the first electrode; a second current collecting member connected to the second electrode, The cell case includes a case body and a lid, the case body has an opening that opens on one side in an axial direction of the wound electrode body when viewed from the wound electrode body, The lid closes the opening of the case body, the lid includes a first external terminal and a second external terminal; the first external terminal is disposed so as to overlap with a radial center of the wound electrode body when viewed from the axial direction, The second external terminal is fixed to the case body, the first current collecting member is disposed on the one side in the axial direction of the wound electrode body and is connected to the first external terminal, a second current collecting member that is disposed on one side of the wound electrode body in the axial direction, and that is disposed between the case body and the second external terminal, and that is joined to the second external terminal by being fixed to the case body together with the second external terminal.

2. the case body further includes a crimped portion formed by crimping an end portion on the one side of the wound electrode body, The energy storage cell according to claim 1 , wherein the second current collecting member is fixed to the crimping portion together with the second external terminal.

3. The energy storage cell according to claim 2 , wherein the case body further includes an electrically insulating seal layer disposed between the second external terminal and the second current collecting member and between the crimping portion and the second external terminal and the second current collecting member.

4. A wound electrode body including a first electrode and a second electrode; a cell case that houses the wound electrode body; a first current collecting member connected to the first electrode; a second current collecting member connected to the second electrode, The cell case includes a case body and a lid, the case body is conductive and has an opening that opens on one side in an axial direction of the wound electrode body when viewed from the wound electrode body, The lid closes the opening of the case body, the lid includes a first external terminal and a second external terminal; the first external terminal is disposed so as to overlap with a radial center of the wound electrode body when viewed from the axial direction, the second external terminal is directly joined to the case body, the first current collecting member is disposed on the one side in the axial direction of the wound electrode body and is connected to the first external terminal, the second current collecting member is disposed on the other side of the wound electrode body in the axial direction and is directly connected to the case body.

5. The energy storage cell according to claim 4 , wherein the second external terminal is joined to the case body by welding.

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