JP2022070631A - Power storage cell - Google Patents

Abstract

To provide a power storage cell which can suppress reduction in sealability.SOLUTION: A through-hole 28, which is located closer to a positive electrode active material layer 22 and a negative electrode active material layer 23 than it is to a seal member 14, brings the inside of a space S into communication with the outside thereof. Thus, a member for bringing the inside of the space S into communication with the outside thereof need not be provided in a manner penetrating the seal member 14. This prevents the member for bringing the inside of the space S into communication with the outside thereof from causing insufficient heat input to the seal member 14, thereby eliminating the risk of reducing the sealability of the seal member 14.SELECTED DRAWING: Figure 4

Description

本発明は、蓄電セルに関する。 The present invention relates to a power storage cell.

特許文献１に記載の双極型二次電池は、積層された正極及び負極と、積層方向における正極と負極との間に位置するセパレータと、積層方向において正極と負極に挟まれる樹脂製のシール部材と、を有する。電解液は、正極と負極とシール部材とによって画定される空間内に封入されている。例えば、電解液を空間内に容易に注入するために、筒部材としての連通部材を有する場合がある。連通部材は、シール部材を貫通して空間の内側と外側とを連通させる。 The bipolar secondary battery described in Patent Document 1 has a laminated positive electrode and a negative electrode, a separator located between the positive electrode and the negative electrode in the laminated direction, and a resin sealing member sandwiched between the positive electrode and the negative electrode in the laminated direction. And have. The electrolytic solution is enclosed in a space defined by a positive electrode, a negative electrode, and a sealing member. For example, it may have a communication member as a tubular member in order to easily inject the electrolytic solution into the space. The communication member penetrates the seal member to communicate the inside and the outside of the space.

特開２０１２－５９４５０号公報Japanese Unexamined Patent Publication No. 2012-59450

ところで、樹脂製のシール部材は、電解液が封入される空間を確実に封止するために、入熱及び溶融させて正極が有する集電体及び負極が有する集電体に溶着されることがある。しかしながら、連通部材がシール部材を貫通する構成において、シール部材における連通部材の貫通する箇所は当該連通部材を原因として入熱が不十分になりやすく、シール部材と集電体との溶着が局所的に脆弱になるため、シール部材と集電体とが剥離してシール性が低下する虞がある。 By the way, in order to surely seal the space in which the electrolytic solution is sealed, the resin sealing member may be heat-loaded and melted and welded to the current collector of the positive electrode and the current collector of the negative electrode. be. However, in the configuration in which the communicating member penetrates the seal member, heat input tends to be insufficient at the portion of the seal member where the communicating member penetrates due to the communicating member, and welding between the sealing member and the current collector is local. Because it becomes fragile, there is a risk that the sealing member and the current collector will peel off and the sealing performance will deteriorate.

上記課題を解決するための蓄電セルは、第１集電体を有する正極と、第２集電体を有し、前記正極に重ねて配置される負極と、前記第１集電体と、前記第２集電体と、の間に配置され、前記第１集電体と、前記第２集電体と、に接合されたシール部材と、前記正極と前記負極との積層方向に重なる前記第１集電体及び第２集電体と、前記シール部材と、によって画定される空間と、を備え、前記第１集電体は、当該第１集電体の第１面において正極活物質層が存在する第１塗工部と、当該第１集電体の第１面の露出する第１未塗工部と、を有し、前記第２集電体は、当該第２集電体の第１面において負極活物質層が存在する第２塗工部と、当該第２集電体の第１面の露出する第２未塗工部と、を有する蓄電セルであって、前記第１未塗工部又は前記第２未塗工部を前記積層方向に貫通する貫通孔と、前記貫通孔を閉塞する閉塞部材と、を有し、前記積層方向の外面から見た平面視において、前記貫通孔は、前記シール部材よりも前記正極活物質層及び前記負極活物質層寄りに位置する。 The storage cell for solving the above problems includes a positive electrode having a first current collector, a negative electrode having a second current collector and being arranged on the positive electrode, the first current collector, and the above. The first, which is arranged between the second current collectors, has a seal member joined to the first current collector and the second current collector, and overlaps the positive electrode and the negative electrode in the stacking direction. The first collector includes a space defined by the first collector, the second collector, and the seal member, and the first collector is a positive electrode active material layer on the first surface of the first collector. The second collector has a first coated portion and an exposed first uncoated portion on the first surface of the first collector, and the second collector is of the second collector. A storage cell comprising a second coated portion on which a negative electrode active material layer is present on the first surface and an exposed second uncoated portion on the first surface of the second current collector. It has a through hole that penetrates the uncoated portion or the second uncoated portion in the stacking direction, and a closing member that closes the through hole. The through hole is located closer to the positive electrode active material layer and the negative electrode active material layer than the sealing member.

これによれば、シール部材よりも正極活物質層及び前記負極活物質層寄りに位置する貫通孔によって空間の内側と外側を連通させる。つまり、空間の内側と外側を連通させるための部材を、シール部材を貫通させて設ける必要がない。このため、シール部材を第１集電体及び第２集電体に接合するための第１集電体、シール部材、及び第２集電体に対する入熱が、空間の内側と外側を連通させるための部材に妨げられずに行われ、シール部材のシール性が低下する虞がない。 According to this, the inside and the outside of the space are communicated with each other by the through hole located closer to the positive electrode active material layer and the negative electrode active material layer than the sealing member. That is, it is not necessary to provide a member for communicating the inside and the outside of the space through the seal member. Therefore, heat input to the first current collector, the seal member, and the second current collector for joining the seal member to the first current collector and the second current collector causes the inside and the outside of the space to communicate with each other. It is performed without being hindered by the member for the purpose, and there is no possibility that the sealing property of the sealing member is deteriorated.

また、閉塞部材によって空間を封止できるため、空間の内側の電解液が貫通孔を通じて空間の外側に洩れることを抑制できる。
上記蓄電セルにおいて、前記閉塞部材は、前記貫通孔から前記積層方向に突出している突出部を含み、前記積層方向への、前記突出部の厚みは、前記正極活物質層の厚み、及び前記負極活物質層の厚みの和以下であるとよい。 Further, since the space can be sealed by the closing member, it is possible to prevent the electrolytic solution inside the space from leaking to the outside of the space through the through hole.
In the storage cell, the closing member includes a protruding portion protruding from the through hole in the stacking direction, and the thickness of the protruding portion in the stacking direction is the thickness of the positive electrode active material layer and the negative electrode. It should be less than or equal to the sum of the thicknesses of the active material layers.

例えば、積層方向において、閉塞部材の突出部の厚みが、正極活物質層の厚み、及び負極活物質層の厚みの和よりも大きい場合を比較例とする。比較例では、複数の蓄電セルを積層すると、突出部を原因として、蓄電セルのうち閉塞部材が配置されている部位が局所的に厚くなってしまう。これに対して、突出部の厚みが、正極活物質層の厚みと負極活物質層の厚みとの和以下であるため、閉塞部材を有する蓄電セルであっても、蓄電セルの積層時に、局所的に厚くなる部位が存在しなくなる。したがって、例えば、拘束荷重が正極活物質層及び負極活物質層へ荷重を十分に付与できないことによる蓄電セルの電池性能の低下を抑制できる。 For example, a comparative example is a case where the thickness of the protruding portion of the closing member is larger than the sum of the thickness of the positive electrode active material layer and the thickness of the negative electrode active material layer in the stacking direction. In the comparative example, when a plurality of storage cells are stacked, the portion of the storage cells in which the blocking member is arranged becomes thick locally due to the protruding portion. On the other hand, since the thickness of the protruding portion is less than or equal to the sum of the thickness of the positive electrode active material layer and the thickness of the negative electrode active material layer, even if the storage cell has a closing member, it is locally present when the storage cells are laminated. There is no part that becomes thicker. Therefore, for example, it is possible to suppress deterioration of the battery performance of the storage cell due to the restraint load not being able to sufficiently apply the load to the positive electrode active material layer and the negative electrode active material layer.

上記蓄電セルにおいて、前記閉塞部材は、前記貫通孔が設けられた未塗工部における前記貫通孔の周囲に溶着されるとともに前記空間を封止する樹脂部材を含むとよい。
これによれば、閉塞部材が樹脂部材を有しているため、樹脂部材が貫通孔の周囲に溶着することにより空間を封止することができる。 In the storage cell, the closing member may include a resin member that is welded around the through hole in the uncoated portion provided with the through hole and seals the space.
According to this, since the closing member has the resin member, the space can be sealed by welding the resin member around the through hole.

上記蓄電セルにおいて、前記樹脂部材は、前記貫通孔が設けられた未塗工部を有する集電体の前記第１面に溶着されているとよい。
これによれば、樹脂部材は、空間の内側に位置するため、内圧が上昇した際に生じる圧力が樹脂部材を第１集電体又は第２集電体に押し付けるように作用し、樹脂部材が第１集電体又は第２集電体から剥がれ難くなり、シール性をより向上することができる。 In the storage cell, the resin member may be welded to the first surface of a current collector having an uncoated portion provided with the through hole.
According to this, since the resin member is located inside the space, the pressure generated when the internal pressure rises acts to press the resin member against the first current collector or the second current collector, and the resin member acts. It becomes difficult to peel off from the first current collector or the second current collector, and the sealing property can be further improved.

上記蓄電セルにおいて、前記閉塞部材は、前記貫通孔に挿入される筒部材を含み、前記筒部材は、前記空間の内側に開口するとともに、前記筒部材を閉塞する遮断部を有しているとよい。 In the storage cell, the closing member includes a tubular member inserted into the through hole, and the tubular member has a blocking portion that opens inside the space and closes the tubular member. good.

これによれば、例えば、空間の外側から内側に電解液を注入する際に、注入装置の供給管を筒部材内に挿入することにより、供給管の先端を筒部材によって保護できる。したがって、供給管の先端が第１未塗工部又は第２未塗工部に接触することを抑制でき、第１集電体又は第２集電体が破れることを抑制できる。また、注液後においては、筒部材に遮断部を設けることにより、空間を封止することができる。 According to this, for example, when injecting an electrolytic solution from the outside to the inside of a space, the tip of the supply pipe can be protected by the tubular member by inserting the supply pipe of the injection device into the tubular member. Therefore, it is possible to prevent the tip of the supply pipe from coming into contact with the first uncoated portion or the second uncoated portion, and it is possible to prevent the first current collector or the second current collector from being broken. Further, after the liquid is injected, the space can be sealed by providing a blocking portion on the tubular member.

上記蓄電セルにおいて、前記筒部材は、前記貫通孔より前記空間の外側に位置する第１部分を有し、前記第１部分は、前記遮断部を有するとよい。
これによれば、例えば、筒部材が第１部分を有しない状態で、筒部材に遮断部を設ける場合に比べると、遮断部を第１部分における第１集電体又は第２集電体よりも外側に設けることができる。このため、遮断部の形成のための溶着の際に、空間内の電解液が加熱されて熱の影響を受けることを抑制でき、蓄電セルの電池性能の低下を抑制できる。 In the storage cell, the tubular member may have a first portion located outside the space from the through hole, and the first portion may have the blocking portion.
According to this, for example, as compared with the case where the tubular member does not have the first portion and the tubular member is provided with a cutoff portion, the cutoff portion is more than the first current collector or the second current collector in the first portion. Can also be provided on the outside. Therefore, it is possible to suppress that the electrolytic solution in the space is heated and affected by heat at the time of welding for forming the blocking portion, and it is possible to suppress deterioration of the battery performance of the storage cell.

上記蓄電セルにおいて、前記筒部材と前記樹脂部材とによって前記貫通孔が閉塞され、前記筒部材は、前記貫通孔より前記空間の内側に位置するとともに先端で開口する第２部分を有し、前記積層方向において、前記貫通孔が設けられた未塗工部を有する集電体と前記第２部分との間には、前記樹脂部材が介在し、前記第２部分が前記貫通孔から前記先端に延出する方向を延出方向とし、前記第２部分の前記延出方向における先端は、前記樹脂部材の前記延出方向における先端よりも前記貫通孔寄りに位置するとよい。 In the storage cell, the through hole is closed by the cylinder member and the resin member, and the cylinder member has a second portion located inside the space from the through hole and opened at the tip thereof. In the stacking direction, the resin member is interposed between the current collector having the uncoated portion provided with the through hole and the second portion, and the second portion is from the through hole to the tip thereof. The extending direction is defined as the extending direction, and the tip of the second portion in the extending direction may be located closer to the through hole than the tip of the resin member in the extending direction.

これによれば、例えば、空間内に電解液を注入する際に、注入装置の供給管を貫通孔に挿入して供給管から空間内に電解液を注入する。このとき、延出方向における第２部分の先端から供給管の先端が飛び出しても、樹脂部材によって、供給管の先端が集電体に接触することを抑制できるため、貫通孔が設けられた未塗工部を有する集電体が破れることを抑制できる。 According to this, for example, when injecting an electrolytic solution into a space, the supply pipe of the injection device is inserted into a through hole and the electrolytic solution is injected into the space from the supply pipe. At this time, even if the tip of the supply pipe protrudes from the tip of the second portion in the extension direction, the resin member can prevent the tip of the supply pipe from coming into contact with the current collector, so that a through hole is not provided. It is possible to prevent the current collector having the coated portion from being torn.

シール性の低下を抑制できる。 It is possible to suppress the deterioration of the sealing property.

実施形態における蓄電装置を示す断面図。FIG. 3 is a sectional view showing a power storage device according to an embodiment. 負極、樹脂部材、及び筒部材の一部分を示す分解斜視図。An exploded perspective view showing a part of a negative electrode, a resin member, and a tubular member. 蓄電セルの一部分を示す断面図。Sectional drawing which shows a part of a storage cell. 図３における４－４線断面図。FIG. 3 is a sectional view taken along line 4-4 in FIG.

以下、蓄電セルを具体化した一実施形態を図１～図４にしたがって説明する。
図１に示すように、蓄電装置１は、複数の蓄電セル１０を積層した積層体２を含んで構成されている。蓄電装置１は、例えばニッケル水素二次電池又はリチウムイオン二次電池等の二次電池である。本実施形態では、蓄電装置１がリチウムイオン二次電池である場合を例示する。複数の蓄電セル１０が積層される方向を蓄電装置１の積層方向とする。各蓄電セル１０は、積層方向に重なり合う正極１１と負極１２を有する。また、各蓄電セル１０は、シール部材１４を備える。なお、正極１１と負極１２とが重なり合う方向を蓄電セル１０の積層方向Ｚとすると、蓄電セル１０の積層方向Ｚは蓄電装置１の積層方向と一致する。蓄電セル１０は、積層方向Ｚにおける正極１１と負極１２の間にセパレータ１３を備えていてもよい。セパレータ１３は、正極１１と負極１２とを隔離することで両極の接触による短絡を防止しつつ、リチウムイオン等の電荷担体を通過させる。セパレータ１３は、積層方向Ｚの一面に第１面１３ａを有し、積層方向Ｚの他面に第２面１３ｂを有する。 Hereinafter, an embodiment in which the storage cell is embodied will be described with reference to FIGS. 1 to 4.
As shown in FIG. 1, the power storage device 1 includes a laminated body 2 in which a plurality of power storage cells 10 are laminated. The power storage device 1 is a secondary battery such as a nickel hydrogen secondary battery or a lithium ion secondary battery. In this embodiment, a case where the power storage device 1 is a lithium ion secondary battery is illustrated. The direction in which the plurality of power storage cells 10 are stacked is defined as the stacking direction of the power storage device 1. Each storage cell 10 has a positive electrode 11 and a negative electrode 12 that overlap each other in the stacking direction. Further, each storage cell 10 includes a seal member 14. Assuming that the direction in which the positive electrode 11 and the negative electrode 12 overlap is the stacking direction Z of the power storage cell 10, the stacking direction Z of the power storage cell 10 coincides with the stacking direction of the power storage device 1. The storage cell 10 may include a separator 13 between the positive electrode 11 and the negative electrode 12 in the stacking direction Z. The separator 13 separates the positive electrode 11 and the negative electrode 12 to prevent a short circuit due to contact between the two electrodes, and allows a charge carrier such as lithium ion to pass therethrough. The separator 13 has a first surface 13a on one surface in the stacking direction Z and a second surface 13b on the other surface in the stacking direction Z.

正極１１は、第１集電体２０と、正極活物質層２２と、を有する。第１集電体２０は、積層方向Ｚの一面に第１面２０ａを有し、積層方向Ｚの他面に第２面２０ｂを有する。正極活物質層２２は、第１集電体２０の第１面２０ａに位置する。第１集電体２０の第２面２０ｂには、正極活物質層２２が設けられていない。積層方向Ｚに蓄電セル１０を見た平面視において、正極１１は、長辺と短辺とを有する矩形状の電極である。また、積層方向Ｚに蓄電セル１０を見た平面視において、第１集電体２０は、長辺と短辺とを有する矩形状である。 The positive electrode 11 has a first current collector 20 and a positive electrode active material layer 22. The first current collector 20 has a first surface 20a on one surface of the stacking direction Z and a second surface 20b on the other surface of the stacking direction Z. The positive electrode active material layer 22 is located on the first surface 20a of the first current collector 20. The positive electrode active material layer 22 is not provided on the second surface 20b of the first current collector 20. In a plan view of the storage cell 10 in the stacking direction Z, the positive electrode 11 is a rectangular electrode having a long side and a short side. Further, in a plan view of the storage cell 10 in the stacking direction Z, the first current collector 20 has a rectangular shape having a long side and a short side.

負極１２は、第２集電体２１と、負極活物質層２３と、を有する。第２集電体２１は、積層方向Ｚの一面に第１面２１ａを有し、積層方向Ｚの他面に第２面２１ｂを有する。負極活物質層２３は、第２集電体２１の第１面２１ａに位置する。第２集電体２１の第２面２１ｂには、負極活物質層２３が設けられていない。積層方向Ｚに蓄電セル１０を平面視に見た平面視において、負極１２は、長辺と短辺とを有する矩形状の電極である。また、積層方向Ｚに蓄電セル１０を見た平面視において、第２集電体２１は、長辺と短辺とを有する矩形状である。 The negative electrode 12 has a second current collector 21 and a negative electrode active material layer 23. The second current collector 21 has a first surface 21a on one surface of the stacking direction Z and a second surface 21b on the other surface of the stacking direction Z. The negative electrode active material layer 23 is located on the first surface 21a of the second current collector 21. The negative electrode active material layer 23 is not provided on the second surface 21b of the second current collector 21. In a plan view of the storage cell 10 in the stacking direction Z in a plan view, the negative electrode 12 is a rectangular electrode having a long side and a short side. Further, in a plan view of the storage cell 10 in the stacking direction Z, the second current collector 21 has a rectangular shape having a long side and a short side.

蓄電セル１０において、第１集電体２０の第１面２０ａと第２集電体２１の第１面２１ａは積層方向Ｚに対向する。つまり、正極１１と負極１２は積層方向Ｚに重なり合っている。負極活物質層２３は、セパレータ１３を介して正極活物質層２２と積層方向Ｚに対向するように配置されている。積層方向Ｚに蓄電セル１０を見た平面視において、正極活物質層２２及び負極活物質層２３のそれぞれは矩形状である。積層方向Ｚに蓄電セル１０を見た平面視において、負極活物質層２３は、正極活物質層２２よりも一回り大きく形成されている。積層方向Ｚに蓄電セル１０を見た平面視において、正極活物質層２２の形成領域の全体が、負極活物質層２３の形成領域の内側に位置している。 In the storage cell 10, the first surface 20a of the first current collector 20 and the first surface 21a of the second current collector 21 face each other in the stacking direction Z. That is, the positive electrode 11 and the negative electrode 12 overlap each other in the stacking direction Z. The negative electrode active material layer 23 is arranged so as to face the positive electrode active material layer 22 in the stacking direction Z via the separator 13. In a plan view of the storage cell 10 in the stacking direction Z, each of the positive electrode active material layer 22 and the negative electrode active material layer 23 has a rectangular shape. The negative electrode active material layer 23 is formed to be one size larger than the positive electrode active material layer 22 in a plan view of the storage cell 10 in the stacking direction Z. In a plan view of the storage cell 10 in the stacking direction Z, the entire formation region of the positive electrode active material layer 22 is located inside the formation region of the negative electrode active material layer 23.

図示しない拘束部材によって蓄電セル１０には積層方向Ｚへ拘束荷重が加えられている。拘束荷重により正極活物質層２２と負極活物質層２３とが積層方向Ｚに互いに近づけられている。 A restraint load is applied to the storage cell 10 in the stacking direction Z by a restraint member (not shown). The positive electrode active material layer 22 and the negative electrode active material layer 23 are brought close to each other in the stacking direction Z by the restraining load.

積層体２において、積層方向に隣り合う蓄電セル１０同士は、一方の蓄電セル１０の第１集電体２０の第２面２０ｂと、他方の蓄電セル１０の第２集電体２１の第２面２１ｂとが互いに接するように積層される。これにより、積層体２の積層方向に隣り合う蓄電セル１０同士が電気的に直列に接続される。積層体２では、積層方向Ｚに隣り合う蓄電セル１０により互いに接する第１集電体２０及び第２集電体２１を電極体とする疑似的なバイポーラ電極３が形成される。すなわち、１つのバイポーラ電極３は、第１集電体２０、第２集電体２１、正極活物質層２２、及び負極活物質層２３を含む。 In the laminated body 2, the storage cells 10 adjacent to each other in the stacking direction are the second surface 20b of the first current collector 20 of one storage cell 10 and the second current collector 21 of the other storage cell 10. The surfaces 21b are laminated so as to be in contact with each other. As a result, the storage cells 10 adjacent to each other in the stacking direction of the laminated body 2 are electrically connected in series. In the laminated body 2, a pseudo bipolar electrode 3 having the first current collector 20 and the second current collector 21 in contact with each other by the storage cells 10 adjacent to each other in the stacking direction Z is formed. That is, one bipolar electrode 3 includes a first current collector 20, a second current collector 21, a positive electrode active material layer 22, and a negative electrode active material layer 23.

蓄電装置１における積層方向Ｚの第１端部６には、終端電極として第１集電体２０が配置される。蓄電装置１における積層方向Ｚの第２端部７には、終端電極として第２集電体２１が配置される。 A first current collector 20 is arranged as a terminal electrode at the first end 6 of the stacking direction Z in the power storage device 1. A second current collector 21 is arranged as a terminal electrode at the second end portion 7 of the stacking direction Z in the power storage device 1.

蓄電装置１は、積層方向Ｚにおいて積層体２を挟むように配置された正極通電板６０及び負極通電板７０を備える。蓄電装置１は、正極通電板６０及び負極通電板７０からなる一対の通電体を備える。正極通電板６０及び負極通電板７０の各々は導電性材料で構成される。正極通電板６０は、積層方向Ｚの第１端部６において最も外側に配置された第１集電体２０に電気的に接続される。負極通電板７０は、積層方向Ｚの第２端部７において最も外側に配置された第２集電体２１に電気的に接続される。正極通電板６０及び負極通電板７０のそれぞれに設けられた図示しない端子を通じて蓄電装置１の充放電が行われる。正極通電板６０を構成する材料としては、第１集電体２０を構成する材料を用いることができる。正極通電板６０は、積層体２に用いられた第１集電体２０よりも厚い金属板で構成してもよい。負極通電板７０を構成する材料としては、第２集電体２１を構成する材料を用いることができる。負極通電板７０は、積層体２に用いられた第２集電体２１よりも厚い金属板で構成してもよい。 The power storage device 1 includes a positive electrode energizing plate 60 and a negative electrode energizing plate 70 arranged so as to sandwich the laminated body 2 in the stacking direction Z. The power storage device 1 includes a pair of energizing bodies including a positive electrode energizing plate 60 and a negative electrode energizing plate 70. Each of the positive electrode current-carrying plate 60 and the negative electrode current-carrying plate 70 is made of a conductive material. The positive electrode current-carrying plate 60 is electrically connected to the first current collector 20 arranged on the outermost side at the first end portion 6 in the stacking direction Z. The negative electrode energizing plate 70 is electrically connected to the second current collector 21 arranged on the outermost side at the second end portion 7 in the stacking direction Z. Charging and discharging of the power storage device 1 is performed through terminals (not shown) provided on each of the positive electrode energizing plate 60 and the negative electrode energizing plate 70. As the material constituting the positive electrode current-carrying plate 60, the material constituting the first current collector 20 can be used. The positive electrode current-carrying plate 60 may be made of a metal plate thicker than the first current collector 20 used for the laminated body 2. As the material constituting the negative electrode current-carrying plate 70, the material constituting the second current collector 21 can be used. The negative electrode current-carrying plate 70 may be made of a metal plate thicker than the second current collector 21 used for the laminated body 2.

第１集電体２０及び第２集電体２１は、化学的に不活性な電気伝導体である。第１集電体２０及び第２集電体２１を構成する材料としては、例えば、金属材料、導電性樹脂材料、導電性無機材料等を用いることができる。導電性樹脂材料としては、例えば、導電性高分子材料又は非導電性高分子材料に必要に応じて導電性フィラーが添加された樹脂等が挙げられる。第１集電体２０及び第２集電体２１は、前述した金属材料又は導電性樹脂材料を含む１以上の層を含む複数層を備えてもよい。第１集電体２０及び第２集電体２１の表面に、メッキ処理又はスプレーコート等の公知の方法により被覆層を形成してもよい。第１集電体２０及び第２集電体２１は、例えば、板状、箔状、シート状、フィルム状、メッシュ状等の形態に形成されていてもよい。第１集電体２０及び第２集電体２１を金属箔とする場合、例えば、アルミニウム箔、銅箔、ニッケル箔、チタン箔、又はステンレス鋼箔等を用いることができる。第１集電体２０及び第２集電体２１としてステンレス鋼箔を用いる場合、例えばＪＩＳ Ｇ ４３０５：２０１５にて規定されるＳＵＳ３０４、ＳＵＳ３１６、ＳＵＳ３０１、ＳＵＳ３０４等を用いると、第１集電体２０及び第２集電体２１の機械的強度を確保することができる。第１集電体２０及び第２集電体２１は、上記金属の合金箔又はクラッド箔であってもよい。本実施形態において、第１集電体２０はアルミニウム箔であり、第２集電体２１は銅箔である。第１集電体２０及び第２集電体２１は、箔状である場合、厚みを例えば、１μｍ～１００μｍとすればよい。 The first current collector 20 and the second current collector 21 are chemically inert electric conductors. As the material constituting the first current collector 20 and the second current collector 21, for example, a metal material, a conductive resin material, a conductive inorganic material, or the like can be used. Examples of the conductive resin material include a conductive polymer material and a resin obtained by adding a conductive filler to a non-conductive polymer material as needed. The first current collector 20 and the second current collector 21 may include a plurality of layers including one or more layers including the above-mentioned metal material or conductive resin material. A coating layer may be formed on the surfaces of the first current collector 20 and the second current collector 21 by a known method such as plating or spray coating. The first current collector 20 and the second current collector 21 may be formed in, for example, a plate shape, a foil shape, a sheet shape, a film shape, a mesh shape, or the like. When the first current collector 20 and the second current collector 21 are metal foils, for example, aluminum foil, copper foil, nickel foil, titanium foil, stainless steel foil and the like can be used. When stainless steel foil is used as the first current collector 20 and the second current collector 21, for example, when SUS304, SUS316, SUS301, SUS304, etc. specified in JIS G 4305: 2015 are used, the first current collector 20 is used. And the mechanical strength of the second current collector 21 can be ensured. The first current collector 20 and the second current collector 21 may be the alloy foil or the clad foil of the metal. In the present embodiment, the first current collector 20 is an aluminum foil and the second current collector 21 is a copper foil. When the first current collector 20 and the second current collector 21 are foil-shaped, the thickness may be, for example, 1 μm to 100 μm.

正極活物質層２２は、リチウムイオン等の電荷担体を吸蔵及び放出し得る正極活物質を含む。正極活物質としては、層状岩塩構造を有するリチウム複合金属酸化物、スピネル構造の金属酸化物、ポリアニオン系化合物などを採用すればよい。また、正極活物質としては、２種以上の正極活物質を併用してもよい。本実施形態において、正極活物質層２２は複合活物質としてのオリビン型リン酸鉄リチウム（ＬｉＦｅＰＯ_４）を含む。 The positive electrode active material layer 22 contains a positive electrode active material that can occlude and release charge carriers such as lithium ions. As the positive electrode active material, a lithium composite metal oxide having a layered rock salt structure, a metal oxide having a spinel structure, a polyanionic compound, or the like may be adopted. Further, as the positive electrode active material, two or more kinds of positive electrode active materials may be used in combination. In the present embodiment, the positive electrode active material layer 22 contains olivine-type lithium iron phosphate (LiFePO ₄ ) as a composite active material.

負極活物質層２３は、リチウムイオン等の電荷担体を吸蔵及び放出可能である単体、合金、又は、炭素、金属化合物、リチウムと合金化可能な元素もしくはその化合物等が挙げられる。炭素としては天然黒鉛、人造黒鉛、あるいはハードカーボン（難黒鉛化性炭素）又はソフトカーボン（易黒鉛化性炭素）が挙げられる。人造黒鉛としては、高配向性グラファイト、メソカーボンマイクロビーズ等が挙げられる。リチウムと合金化可能な元素の例としては、シリコン（ケイ素）及びスズが挙げられる。本実施形態において、負極活物質層２３は炭素系材料としての黒鉛を含む。 Examples of the negative electrode active material layer 23 include simple substances, alloys, carbon, metal compounds, elements that can be alloyed with lithium, or compounds thereof, which can occlude and release charge carriers such as lithium ions. Examples of carbon include natural graphite, artificial graphite, hard carbon (non-graphitizable carbon) or soft carbon (easy graphitizable carbon). Examples of artificial graphite include highly oriented graphite and mesocarbon microbeads. Examples of elements that can be alloyed with lithium include silicon and tin. In the present embodiment, the negative electrode active material layer 23 contains graphite as a carbon-based material.

正極活物質層２２及び負極活物質層２３は、必要に応じて電気伝導性を高めるための導電助材、結着剤、電解質（ポリマーマトリクス、イオン伝導性ポリマー、電解液等）、イオン伝導性を高めるための電解質支持塩（リチウム塩）等をさらに含み得る。活物質層に含まれる成分又は成分の配合比及び活物質層の厚さは特に限定されず、リチウムイオン二次電池についての公知の知見が適宜参照され得る。活物質層の厚みは、例えば２μｍ～１５０μｍである。第１集電体２０及び第２集電体２１の表面に活物質層を形成させるために、ロールコート法等の公知の方法を用いてもよい。正極１１又は負極１２の熱安定性を向上させるために、第１集電体２０及び第２集電体２１の表面（片面又は両面）又は正極活物質層２２及び負極活物質層２３の表面に耐熱層を設けてもよい。耐熱層は、例えば、無機粒子と結着剤とを含み、その他に増粘剤等の添加剤を含んでもよい。 The positive electrode active material layer 22 and the negative electrode active material layer 23 are a conductive auxiliary material, a binder, an electrolyte (polymer matrix, an ionic conductive polymer, an electrolytic solution, etc.) for increasing electrical conductivity, and ionic conductivity, if necessary. It may further contain an electrolyte-supporting salt (lithium salt) or the like for enhancing the above. The components contained in the active material layer or the compounding ratio of the components and the thickness of the active material layer are not particularly limited, and known knowledge about the lithium ion secondary battery can be appropriately referred to. The thickness of the active material layer is, for example, 2 μm to 150 μm. In order to form an active material layer on the surfaces of the first current collector 20 and the second current collector 21, a known method such as a roll coating method may be used. In order to improve the thermal stability of the positive electrode 11 or the negative electrode 12, on the surface (one side or both sides) of the first current collector 20 and the second current collector 21 or on the surface of the positive electrode active material layer 22 and the negative electrode active material layer 23. A heat-resistant layer may be provided. The heat-resistant layer may contain, for example, inorganic particles and a binder, and may also contain an additive such as a thickener.

導電助剤は、正極１１又は負極１２の導電性を高めるために添付される。導電助剤は、例えば、アセチレンブラック、カーボンブラック、グラファイト等である。
結着剤としては、ポリフッ化ビニリデン、ポリテトラフルオロエチレン、フッ化ゴム等の含フッ素樹脂、ポリプロピレン、ポリエチレン等の熱可塑性樹脂、ポリイミド、ポリアミド等のイミド系樹脂、アルコキシシリル基含有樹脂、アクリル酸やメタクリル酸などのモノマー単位を含むアクリル系樹脂、スチレン―ブタジエンゴム（ＳＢＲ）、カルボキシメチルセルロース、アルギン酸ナトリウム、アルギン酸アンモニウム等のアルギン酸塩、水溶性セルロースエステル架橋体、デンプン―アクリル酸グラフト重合体が挙げられる。これらの結着剤は、単独で又は複数で用いられ得る。溶媒としては、例えば、水、Ｎ―メチル―２―ピロドリン（ＮＭＰ）等が用いられる。 The conductive auxiliary agent is attached to increase the conductivity of the positive electrode 11 or the negative electrode 12. The conductive auxiliary agent is, for example, acetylene black, carbon black, graphite or the like.
Examples of the binder include fluororesins such as polyvinylidene fluoride, polytetrafluoroethylene and rubber fluoride, thermoplastic resins such as polypropylene and polyethylene, imide resins such as polyimides and polyamides, alkoxysilyl group-containing resins and acrylic acids. Acrylic resins containing monomer units such as methacrylic acid, styrene-butadiene rubber (SBR), carboxymethyl cellulose, sodium alginate, arginates such as ammonium alginate, water-soluble cellulose ester cross-linking products, starch-acrylic acid graft polymers. Be done. These binders can be used alone or in combination. As the solvent, for example, water, N-methyl-2-pyrodrin (NMP) and the like are used.

セパレータ１３は、例えば、電解質を吸収保持するポリマーを含む多孔性シート又は不織布であってもよい。セパレータ１３を構成する材料としては、例えば、ポリプロピレン、ポリエチレン、ポリオレフィン、ポリエステル等が挙げられる。セパレータ１３は、単層構造又は多層構造を有してもよい。多層構造は、例えば、接着層、耐熱層としてのセラミック層等を有してもよい。セパレータ１３には、電解質が含浸されてもよく、セパレータ１３自体を高分子ゲル電解質又は無機型電解質等の電解質で構成してもよい。 The separator 13 may be, for example, a porous sheet or a non-woven fabric containing a polymer that absorbs and retains an electrolyte. Examples of the material constituting the separator 13 include polypropylene, polyethylene, polyolefin, polyester and the like. The separator 13 may have a single-layer structure or a multi-layer structure. The multilayer structure may have, for example, an adhesive layer, a ceramic layer as a heat-resistant layer, and the like. The separator 13 may be impregnated with an electrolyte, or the separator 13 itself may be composed of an electrolyte such as a polymer gel electrolyte or an inorganic electrolyte.

セパレータ１３に含浸される電解質としては、例えば、非水溶媒と非水溶媒に溶解した電解質塩とを含む液体電解質（電解液）、又はポリマーマトリックス中に保持された電解質を含む高分子ゲル電解質等が挙げられる。 Examples of the electrolyte impregnated in the separator 13 include a liquid electrolyte (electrolyte solution) containing a non-aqueous solvent and an electrolyte salt dissolved in the non-aqueous solvent, a polymer gel electrolyte containing an electrolyte held in a polymer matrix, and the like. Can be mentioned.

セパレータ１３に電解液が含浸される場合、その電解質塩として、ＬｉＣｌＯ_４、ＬｉＡｓＦ_６ＬｉＰＦ_６、ＬｉＢＦ_４、ＬｉＣＦ_３ＳＯ_３、ＬｉＮ（ＦＳＯ_２）_２、ＬｉＮ（ＣＦ_３ＳＯ_２）_２、等の公知のリチウム塩を使用できる。また、非水溶媒として、環状カーボネート類、環状エステル類、鎖状カーボネート類、鎖状エステル類、エーテル類等の公知の溶媒を使用できる。なお、これら公知の溶媒材料を二種以上組み合わせて用いてもよい。 When the separator 13 is impregnated with an electrolytic solution, the electrolyte salts thereof include LiClO ₄ , LiAsF ₆ , LiPF ₆ , LiBF ₄ , LiCF ₃ SO ₃ , LiN (FSO ₂ ) ₂ , LiN (CF ₃ SO ₂ ) ₂ , and the like. Known lithium salts can be used. Further, as the non-aqueous solvent, known solvents such as cyclic carbonates, cyclic esters, chain carbonates, chain esters, ethers and the like can be used. In addition, you may use two or more kinds of these known solvent materials in combination.

シール部材１４は、第１集電体２０の縁部及び第２集電体２１の縁部に沿って延びる。積層方向Ｚに沿って外側から蓄電セル１０を見た平面視において、シール部材１４は、正極活物質層２２及び負極活物質層２３の周囲を取り囲む矩形枠状である。シール部材１４は、積層方向Ｚにおける第１集電体２０と第２集電体２１との間に位置する。シール部材１４は、第１集電体２０及び第２集電体２１に溶着されている。シール部材１４は、絶縁材料を含み、第１集電体２０と第２集電体２１との間を絶縁することによって短絡を防止する。 The seal member 14 extends along the edge of the first current collector 20 and the edge of the second current collector 21. In a plan view of the storage cell 10 viewed from the outside along the stacking direction Z, the seal member 14 has a rectangular frame shape surrounding the positive electrode active material layer 22 and the negative electrode active material layer 23. The seal member 14 is located between the first current collector 20 and the second current collector 21 in the stacking direction Z. The seal member 14 is welded to the first current collector 20 and the second current collector 21. The sealing member 14 contains an insulating material and prevents a short circuit by insulating between the first current collector 20 and the second current collector 21.

シール部材１４は、第１集電体２０と第２集電体２１とシール部材１４とによって画定される空間Ｓを封止する。シール部材１４は、空間Ｓに収容された電解液の外側への流出を抑制する。また、シール部材１４は、外側から空間Ｓ内への水分の侵入を抑制する。本実施形態では、シール部材１４の材料は、酸変性ポリエチレンである。なお、シール部材１４の材料は、酸変性ポリプロピレンであってもよい。 The seal member 14 seals the space S defined by the first current collector 20, the second current collector 21, and the seal member 14. The sealing member 14 suppresses the outflow of the electrolytic solution contained in the space S to the outside. Further, the seal member 14 suppresses the intrusion of moisture from the outside into the space S. In this embodiment, the material of the sealing member 14 is acid-modified polyethylene. The material of the sealing member 14 may be acid-modified polypropylene.

図１又は図４に示すように、第１集電体２０は、第１面２０ａにおいて正極活物質層２２が存在する第１塗工部２４と、第１面２０ａの露出する第１未塗工部２５と、を有する。積層方向Ｚに蓄電セル１０を見た平面視において、第１未塗工部２５は、第１塗工部２４を囲む矩形枠状である。 As shown in FIG. 1 or 4, in the first current collector 20, the first coated portion 24 in which the positive electrode active material layer 22 is present on the first surface 20a and the exposed first uncoated portion 20a of the first surface 20a. It has a work unit 25 and. The first uncoated portion 25 has a rectangular frame shape surrounding the first coated portion 24 in a plan view of the storage cell 10 in the stacking direction Z.

図２又は図４に示すように、第２集電体２１は、第１面２１ａにおいて負極活物質層２３が存在する第２塗工部２６と、第１面２１ａの露出する第２未塗工部２７と、を有する。積層方向Ｚに蓄電セル１０を見た平面視において、第２未塗工部２７は、第２塗工部２６を囲む矩形枠状である。第２集電体２１のうちの短辺に沿う方向を短辺方向Ｘとする。 As shown in FIG. 2 or 4, the second current collector 21 has a second coated portion 26 in which the negative electrode active material layer 23 is present on the first surface 21a and an exposed second uncoated portion on the first surface 21a. It has a work unit 27 and. The second uncoated portion 27 has a rectangular frame shape surrounding the second coated portion 26 in a plan view of the storage cell 10 in the stacking direction Z. The direction along the short side of the second current collector 21 is defined as the short side direction X.

積層方向Ｚに蓄電セル１０を見た平面視において、第１集電体２０と第２集電体２１とは同じ大きさである。また、負極活物質層２３は、正極活物質層２２よりも一回り大きい。このため、第２集電体２１の各端縁に直交する方向への第２未塗工部２７の寸法は、第１集電体２０の各端縁に直交する方向への第１未塗工部２５の寸法よりも小さい。 The first current collector 20 and the second current collector 21 have the same size in a plan view of the storage cell 10 in the stacking direction Z. Further, the negative electrode active material layer 23 is one size larger than the positive electrode active material layer 22. Therefore, the dimension of the second unpainted portion 27 in the direction orthogonal to each edge of the second current collector 21 is the first unpainted portion in the direction orthogonal to each edge of the first current collector 20. It is smaller than the size of the work part 25.

シール部材１４において積層方向Ｚの一端に位置する第１端面１４ａは、第１集電体２０の第１面２０ａにおける第１未塗工部２５に溶着されている。シール部材１４において積層方向Ｚの他端に位置する第２端面１４ｂは、第２集電体２１の第１面２１ａにおける第２未塗工部２７に溶着されている。 The first end surface 14a located at one end of the stacking direction Z in the seal member 14 is welded to the first uncoated portion 25 on the first surface 20a of the first current collector 20. The second end surface 14b located at the other end of the stacking direction Z in the seal member 14 is welded to the second uncoated portion 27 on the first surface 21a of the second current collector 21.

シール部材１４の第１端面１４ａと第１集電体２０の第１面２０ａとの溶着、及びシール部材１４の第２端面１４ｂと第２集電体２１の第１面２１ａとの溶着は、第１集電体２０と、シール部材１４と、第２集電体２１とを積層方向Ｚに重ねた状態で、第１集電体２０、シール部材１４、及び第２集電体２１に、入熱して行われる。 The welding of the first end surface 14a of the seal member 14 and the first surface 20a of the first current collector 20 and the welding of the second end surface 14b of the seal member 14 and the first surface 21a of the second current collector 21 are performed. With the first current collector 20, the seal member 14, and the second current collector 21 stacked in the stacking direction Z, the first current collector 20, the seal member 14, and the second current collector 21 are placed on the first current collector 20, the seal member 14, and the second current collector 21. It is done by applying heat.

第２未塗工部２７は、第２未塗工部２７において第２集電体２１を積層方向Ｚに貫通する貫通孔２８を有する。貫通孔２８は、第２集電体２１の第１面２１ａと直交するように、第２集電体２１を貫通している。 The second uncoated portion 27 has a through hole 28 that penetrates the second current collector 21 in the stacking direction Z in the second uncoated portion 27. The through hole 28 penetrates the second current collector 21 so as to be orthogonal to the first surface 21a of the second current collector 21.

図２、図３又は図４に示すように、蓄電セル１０は、貫通孔２８を閉塞する閉塞部材３０を有する。閉塞部材３０は、樹脂部材３１と、筒部材３２と、を含む。樹脂部材３１は、扁平筒状をなしている。樹脂部材３１は、扁平筒の上部を構成する第１樹脂部材３３と、扁平筒の下部を構成する第２樹脂部材３４と、から形成されている。本実施形態では、第１樹脂部材３３及び第２樹脂部材３４の材料は、酸変性ポリエチレンである。なお、第１樹脂部材３３及び第２樹脂部材３４の材料は、酸変性ポリプロピレンであってもよい。 As shown in FIG. 2, FIG. 3 or FIG. 4, the storage cell 10 has a closing member 30 that closes the through hole 28. The closing member 30 includes a resin member 31 and a tubular member 32. The resin member 31 has a flat tubular shape. The resin member 31 is formed of a first resin member 33 constituting the upper portion of the flat cylinder and a second resin member 34 constituting the lower portion of the flat cylinder. In the present embodiment, the material of the first resin member 33 and the second resin member 34 is acid-modified polyethylene. The material of the first resin member 33 and the second resin member 34 may be acid-modified polypropylene.

第１樹脂部材３３及び第２樹脂部材３４は短辺方向Ｘに一致する長手方向と、積層方向Ｚ及び短辺方向Ｘに交差する短手方向を有する長四角シート状である。第１樹脂部材３３の長手方向に延びる両端縁と、第２樹脂部材３４の長手方向に延びる両端縁と、が溶着されている。樹脂部材３１において、第１樹脂部材３３と第２樹脂部材３４とは、第１樹脂部材３３の短手方向に延びる両端縁と、第２樹脂部材３４の短手方向に延びる両端縁とが重ならないように、第１樹脂部材３３と第２樹脂部材３４とを長手方向にずらして溶着されている。 The first resin member 33 and the second resin member 34 are in the shape of a long square sheet having a longitudinal direction corresponding to the short side direction X and a short direction intersecting the stacking direction Z and the short side direction X. Both end edges extending in the longitudinal direction of the first resin member 33 and both end edges extending in the longitudinal direction of the second resin member 34 are welded. In the resin member 31, the first resin member 33 and the second resin member 34 overlap with both end edges extending in the lateral direction of the first resin member 33 and both end edges extending in the lateral direction of the second resin member 34. The first resin member 33 and the second resin member 34 are welded so as to be displaced in the longitudinal direction so as not to be formed.

平面視において、第２樹脂部材３４と重なる第１樹脂部材３３の短手方向に延びる端縁３３ｂは、第２樹脂部材３４に溶着されていない。平面視において、第１樹脂部材３３と重なる第２樹脂部材３４の短手方向に延びる端縁３４ｂは、第１樹脂部材３３に溶着されていない。樹脂部材３１は、第１樹脂部材３３の長手方向に延びる両端縁と第２樹脂部材３４の長手方向に延びる両端縁とが溶着されることで、第１樹脂部材３３と第２樹脂部材３４との間に画定された隙間に通路３１ｐを有する。 In a plan view, the edge 33b extending in the lateral direction of the first resin member 33 that overlaps with the second resin member 34 is not welded to the second resin member 34. In a plan view, the edge 34b extending in the lateral direction of the second resin member 34 that overlaps with the first resin member 33 is not welded to the first resin member 33. In the resin member 31, the first resin member 33 and the second resin member 34 are formed by welding both end edges extending in the longitudinal direction of the first resin member 33 and both end edges extending in the longitudinal direction of the second resin member 34. It has a passage 31p in the gap defined between the two.

樹脂部材３１において、第１樹脂部材３３の端縁３３ｂと第２樹脂部材３４とが重なる部分において、通路３１ｐが開口している。第２樹脂部材３４のうち、平面視において第１樹脂部材３３の端縁３３ｂから突出する部分によって構成される第２延出部３４ａを有する。また、樹脂部材３１において、第２樹脂部材３４の端縁３４ｂと第１樹脂部材３３とが重なる部分において、通路３１ｐが開口している。第１樹脂部材３３のうち、平面視において第２樹脂部材３４の端縁３４ｂから突出する部分によって構成される第１延出部３３ａを有する。 In the resin member 31, the passage 31p is open at the portion where the edge 33b of the first resin member 33 and the second resin member 34 overlap. Among the second resin members 34, the second resin member 34 has a second extending portion 34a formed by a portion protruding from the end edge 33b of the first resin member 33 in a plan view. Further, in the resin member 31, the passage 31p is opened at the portion where the edge 34b of the second resin member 34 and the first resin member 33 overlap. The first resin member 33 has a first extending portion 33a formed by a portion of the first resin member 33 that protrudes from the edge 34b of the second resin member 34 in a plan view.

樹脂部材３１は、第２集電体２１の第１面２１ａに溶着されている。詳細には、第１樹脂部材３３は、第２集電体２１の第２未塗工部２７での貫通孔２８の周囲に溶着されており、貫通孔２８を閉塞している。また、第２樹脂部材３４の第２延出部３４ａは、第２集電体２１の第２未塗工部２７での貫通孔２８の周囲に溶着されており、貫通孔２８を第１面２１ａ側から閉塞している。 The resin member 31 is welded to the first surface 21a of the second current collector 21. Specifically, the first resin member 33 is welded around the through hole 28 in the second uncoated portion 27 of the second current collector 21, and closes the through hole 28. Further, the second extending portion 34a of the second resin member 34 is welded around the through hole 28 in the second uncoated portion 27 of the second current collector 21, and the through hole 28 is formed on the first surface. It is blocked from the 21a side.

筒部材３２は、第１樹脂部材３３及び第２樹脂部材３４の長手方向に沿った長手方向、及び、第１樹脂部材３３及び第２樹脂部材３４の短手方向に沿った短手方向を有する扁平筒状をなしている。筒部材３２の材料は、酸変性ポリプロピレンである。なお、筒部材３２の材料は、酸変性ポリプロピレンであってもよい。 The cylindrical member 32 has a longitudinal direction along the longitudinal direction of the first resin member 33 and the second resin member 34, and a lateral direction along the lateral direction of the first resin member 33 and the second resin member 34. It has a flat tubular shape. The material of the tubular member 32 is acid-modified polypropylene. The material of the tubular member 32 may be acid-modified polypropylene.

筒部材３２は、筒部材３２の長手方向が樹脂部材３１の長手方向に一致するように樹脂部材３１の通路３１ｐ及び貫通孔２８に挿入されている。筒部材３２の短手方向の寸法は、貫通孔２８の長手方向の寸法よりも小さい。筒部材３２のうち、樹脂部材３１の通路３１ｐに挿入されている部分は、樹脂部材３１と溶着し、封止されている。 The tubular member 32 is inserted into the passage 31p and the through hole 28 of the resin member 31 so that the longitudinal direction of the tubular member 32 coincides with the longitudinal direction of the resin member 31. The lateral dimension of the tubular member 32 is smaller than the longitudinal dimension of the through hole 28. Of the tubular member 32, the portion inserted into the passage 31p of the resin member 31 is welded to the resin member 31 and sealed.

筒部材３２は、貫通孔２８内に位置する筒部本体３５と、筒部本体３５より筒部材３２の第１端部３２ａ寄りに位置する第１部分３６と、筒部本体３５より筒部材３２の第２端部３２ｂ寄りに位置する第２部分３７と、を有する。第１部分３６は、筒部材３２のうち、貫通孔２８（第２集電体２１の第２面２１ｂ）より空間Ｓの外側に位置している部分である。同様に、第２部分３７は、筒部材３２のうち、貫通孔２８（第２集電体２１の第１面２１ａ）より空間Ｓの内側に位置する部分である。筒部本体３５及び第１部分３６は、筒部材３２のうち、通路３１ｐから空間Ｓの外側に延出している部分である。第２部分３７は、筒部材３２のうち、通路３１ｐに挿入されている部分である。第２部分３７の先端は、筒部材３２の第２端部３２ｂであり、通路３１ｐから空間Ｓへ僅かにはみ出している。また、第２部分３７の先端、つまり、筒部材３２の第２端部３２ｂは、樹脂部材３１の第１延出部３３ａによって第２集電体２１側から覆われている。第２部分３７の先端は、空間Ｓに向けて開口している。すなわち、積層方向Ｚにおいて、第２集電体２１と第２部分３７の先端との間には、樹脂部材３１の第１樹脂部材３３が介在している。第２部分３７が貫通孔２８から第２部分３７の先端（第２端部３２ｂ）に延出する方向を延出方向Ｙとする。本実施形態では、延出方向Ｙは、短辺方向Ｘと一致する。第２部分３７の延出方向Ｙにおける先端は、第１延出部３３ａの延出方向Ｙにおける先端よりも貫通孔２８寄りに位置する。 The tubular member 32 includes a tubular portion main body 35 located in the through hole 28, a first portion 36 located closer to the first end portion 32a of the tubular portion 32 than the tubular portion main body 35, and a tubular portion 32 from the tubular portion main body 35. It has a second portion 37 located closer to the second end portion 32b of the above. The first portion 36 is a portion of the tubular member 32 located outside the space S from the through hole 28 (the second surface 21b of the second current collector 21). Similarly, the second portion 37 is a portion of the tubular member 32 located inside the space S from the through hole 28 (the first surface 21a of the second current collector 21). The cylinder portion main body 35 and the first portion 36 are portions of the cylinder member 32 extending from the passage 31p to the outside of the space S. The second portion 37 is a portion of the tubular member 32 that is inserted into the passage 31p. The tip of the second portion 37 is the second end portion 32b of the tubular member 32, and slightly protrudes from the passage 31p into the space S. Further, the tip of the second portion 37, that is, the second end portion 32b of the tubular member 32 is covered from the second current collector 21 side by the first extending portion 33a of the resin member 31. The tip of the second portion 37 is open toward the space S. That is, in the stacking direction Z, the first resin member 33 of the resin member 31 is interposed between the second current collector 21 and the tip of the second portion 37. The direction in which the second portion 37 extends from the through hole 28 to the tip (second end portion 32b) of the second portion 37 is defined as the extension direction Y. In the present embodiment, the extension direction Y coincides with the short side direction X. The tip of the second portion 37 in the extension direction Y is located closer to the through hole 28 than the tip of the first extension portion 33a in the extension direction Y.

筒部材３２において、第１部分３６は、第２集電体２１の第２面２１ｂに沿うように延びており、第２部分３７は、第２集電体２１の第１面２１ａに沿うように延びている。したがって、筒部材３２は、筒部本体３５と第１部分３６との境界にて第１部分３６が第２集電体２１の第２面２１ｂに向かうように折り曲げられている。また、筒部材３２は、筒部本体３５と第２部分３７との境界にて第２部分３７が第２集電体２１の第１面２１ａに向かうように折り曲げられている。第２樹脂部材３４のうち、第２延出部３４ａは、筒部材３２とともに第２集電体２１に向けて折り曲げられる。 In the tubular member 32, the first portion 36 extends along the second surface 21b of the second current collector 21, and the second portion 37 extends along the first surface 21a of the second current collector 21. Extends to. Therefore, the tubular member 32 is bent so that the first portion 36 faces the second surface 21b of the second current collector 21 at the boundary between the tubular portion main body 35 and the first portion 36. Further, the tubular member 32 is bent so that the second portion 37 faces the first surface 21a of the second current collector 21 at the boundary between the tubular portion main body 35 and the second portion 37. Of the second resin member 34, the second extending portion 34a is bent toward the second current collector 21 together with the tubular member 32.

第１部分３６の先端は、遮断部３８を有する。遮断部３８は、溶着されることにより筒部材３２を閉塞し、空間Ｓを封止している。遮断部３８は、筒部材３２の第１端部３２ａが熱によって溶着されることにより形成されている。つまり、遮断部３８は、筒部材３２のうち、空間Ｓから離れた位置に形成されている。すなわち、貫通孔２８が樹脂部材３１と筒部材３２とによって閉塞されるとともに、筒部材３２が遮断部３８によって閉塞されることで、空間Ｓは封止されている。 The tip of the first portion 36 has a blocking portion 38. The blocking portion 38 closes the tubular member 32 by welding and seals the space S. The blocking portion 38 is formed by welding the first end portion 32a of the tubular member 32 by heat. That is, the blocking portion 38 is formed at a position away from the space S in the tubular member 32. That is, the through hole 28 is closed by the resin member 31 and the tubular member 32, and the tubular member 32 is closed by the blocking portion 38, so that the space S is sealed.

本実施形態では、閉塞部材３０のうち、樹脂部材３１は貫通孔２８より空間Ｓの内側に位置しており、筒部材３２は、貫通孔２８の空間Ｓの内側及び外側に位置する部分を有している。換言すると、閉塞部材３０は、樹脂部材３１や筒部材３２の一部で構成された、貫通孔２８から積層方向Ｚに突出する突出部４０を有している。具体的には、突出部４０は、貫通孔２８より積層方向Ｚに空間Ｓの内側へ突出する、樹脂部材３１及び筒部材３２の第２部分３７からなる第１突出部４１と、貫通孔２８より積層方向Ｚに空間Ｓの外側へ突出する、筒部材３２の第１部分３６からなる第２突出部４２と、を含む。 In the present embodiment, of the closing member 30, the resin member 31 is located inside the space S from the through hole 28, and the tubular member 32 has portions located inside and outside the space S of the through hole 28. are doing. In other words, the closing member 30 has a protruding portion 40 that is composed of a part of the resin member 31 and the tubular member 32 and protrudes from the through hole 28 in the stacking direction Z. Specifically, the protruding portion 40 is a first protruding portion 41 composed of a resin member 31 and a second portion 37 of the tubular member 32, which protrudes inward of the space S in the stacking direction Z from the through hole 28, and the through hole 28. It includes a second protruding portion 42 formed of a first portion 36 of the tubular member 32, which protrudes to the outside of the space S in the stacking direction Z.

ここで、第１突出部４１の積層方向Ｚへの厚みＬ１と、第２突出部４２の積層方向Ｚへの厚みＬ２の和である突出部４０の積層方向Ｚへの厚みは、積層方向Ｚへの負極活物質層２３の厚みＬ３よりも小さい。したがって、積層方向Ｚへの突出部４０の厚みは、正極活物質層２２の厚み、及び負極活物質層２３の厚みＬ３の和よりも小さい。このため、積層方向Ｚから見て閉塞部材３０が存在する部分における積層方向Ｚへの蓄電セル１０の厚みは、積層方向Ｚから見て正極活物質層２２及び負極活物質層２３が重なる部分における積層方向Ｚへの蓄電セル１０の厚み以下となる。 Here, the thickness of the protrusion 40 in the stacking direction Z, which is the sum of the thickness L1 of the first protrusion 41 in the stacking direction Z and the thickness L2 of the second protrusion 42 in the stacking direction Z, is the stacking direction Z. It is smaller than the thickness L3 of the negative electrode active material layer 23. Therefore, the thickness of the protruding portion 40 in the stacking direction Z is smaller than the sum of the thickness of the positive electrode active material layer 22 and the thickness L3 of the negative electrode active material layer 23. Therefore, the thickness of the storage cell 10 in the stacking direction Z in the portion where the closing member 30 is present when viewed from the stacking direction Z is the portion where the positive electrode active material layer 22 and the negative electrode active material layer 23 overlap when viewed from the stacking direction Z. It is equal to or less than the thickness of the storage cell 10 in the stacking direction Z.

本実施形態では、以下の作用効果を得ることができる。
（１）シール部材１４よりも正極活物質層２２及び負極活物質層２３寄りに位置する貫通孔２８によって空間Ｓの内側と外側を連通させる。つまり、空間Ｓの内側と外側を連通させるための部材を、シール部材１４を貫通させて設けたり、シール部材１４と第１集電体２０又は第２集電体２１との間に介在させて設けたりする必要がない。シール部材１４と第１集電体２０との溶着、及びシール部材１４と第２集電体２１との溶着を行う際、第１集電体２０とシール部材１４との間、及び第２集電体２１とシール部材１４との間に、空間Ｓの内側と外側を連通させるための部材が介在することがない。このため、第１集電体２０、シール部材１４、及び第２集電体２１に対する入熱が、空間Ｓの内側と外側を連通させるための部材に妨げられずに行われる。その結果、第１集電体２０、シール部材１４、及び第２集電体２１の溶着が局所的に脆弱になることを抑制し、シール部材１４のシール性が低下する虞がない。 In this embodiment, the following effects can be obtained.
(1) The inside and outside of the space S are communicated with each other by the through holes 28 located closer to the positive electrode active material layer 22 and the negative electrode active material layer 23 than the sealing member 14. That is, a member for communicating the inside and the outside of the space S is provided so as to penetrate the seal member 14, or is interposed between the seal member 14 and the first current collector 20 or the second current collector 21. There is no need to install it. When welding the seal member 14 to the first current collector 20 and welding the seal member 14 to the second current collector 21, the space between the first current collector 20 and the seal member 14 and the second current collector are collected. There is no intervening member for communicating the inside and the outside of the space S between the electric body 21 and the seal member 14. Therefore, the heat input to the first current collector 20, the seal member 14, and the second current collector 21 is performed without being hindered by the member for communicating the inside and the outside of the space S. As a result, it is possible to prevent the welding of the first current collector 20, the sealing member 14, and the second current collector 21 from becoming locally fragile, and there is no possibility that the sealing property of the sealing member 14 will deteriorate.

（２）例えば、積層方向Ｚにおいて、閉塞部材３０の突出部４０の厚みが、正極活物質層２２の厚み、及び負極活物質層２３の厚みの和よりも大きい場合を比較例とする。比較例では、複数の蓄電セル１０を積層すると、突出部４０を原因として、蓄電セル１０のうち閉塞部材３０が配置されている部位が局所的に厚くなってしまう。これに対して、突出部４０の厚みが、正極活物質層２２の厚みと負極活物質層２３の厚みＬ３との和よりも小さいため、閉塞部材３０を有する蓄電セル１０であっても、蓄電セル１０の積層時に、局所的に厚くなる部位が存在しなくなる。したがって、例えば、拘束荷重が正極活物質層２２及び負極活物質層２３へ荷重を十分に付与できないことによる蓄電セル１０の電池性能の低下を抑制できる。 (2) For example, in the stacking direction Z, a case where the thickness of the protruding portion 40 of the closing member 30 is larger than the sum of the thickness of the positive electrode active material layer 22 and the thickness of the negative electrode active material layer 23 is taken as a comparative example. In the comparative example, when a plurality of storage cells 10 are stacked, the portion of the storage cells 10 in which the blocking member 30 is arranged becomes thick locally due to the protrusion 40. On the other hand, since the thickness of the protruding portion 40 is smaller than the sum of the thickness of the positive electrode active material layer 22 and the thickness L3 of the negative electrode active material layer 23, even the storage cell 10 having the closing member 30 stores electricity. When the cells 10 are laminated, there is no locally thickened portion. Therefore, for example, it is possible to suppress deterioration of the battery performance of the storage cell 10 due to the restraining load not being able to sufficiently apply the load to the positive electrode active material layer 22 and the negative electrode active material layer 23.

（３）樹脂部材３１は、空間Ｓの内側に位置するため、内圧が上昇した際に生じる圧力が樹脂部材３１を第２集電体２１に押し付けるように作用し、樹脂部材３１が第２集電体２１から剥がれ難くなり、シール性をより向上することができる。 (3) Since the resin member 31 is located inside the space S, the pressure generated when the internal pressure rises acts to press the resin member 31 against the second current collector 21, and the resin member 31 is the second current collector. It becomes difficult to peel off from the electric body 21, and the sealing property can be further improved.

（４）例えば、空間Ｓの外側から内側に電解液を注入する際に、注入装置の供給管を筒部材３２内に挿入することにより、供給管の先端を筒部材３２によって保護して、供給管の先端が第２未塗工部２７に接触することを抑制できる。 (4) For example, when injecting an electrolytic solution from the outside to the inside of the space S, the supply pipe of the injection device is inserted into the tubular member 32, so that the tip of the supply pipe is protected by the tubular member 32 and supplied. It is possible to prevent the tip of the pipe from coming into contact with the second uncoated portion 27.

（５）例えば、筒部材３２が第１部分３６を有しない状態で、筒部材３２に遮断部３８を設ける場合に比べると、遮断部３８を、第１部分３６における第２集電体２１から離れた部位に設けることができるため、溶着の際に、空間Ｓ内の電解液が加熱されて熱の影響を受けることを抑制でき、蓄電セル１０の電池性能の低下を抑制できる。 (5) For example, as compared with the case where the cylinder member 32 is provided with the cutoff portion 38 in a state where the cylinder member 32 does not have the first portion 36, the cutoff portion 38 is separated from the second current collector 21 in the first portion 36. Since it can be provided at a distant portion, it is possible to suppress that the electrolytic solution in the space S is heated and affected by heat at the time of welding, and it is possible to suppress deterioration of the battery performance of the storage cell 10.

（６）例えば、空間Ｓ内に電解液を注入する際に、注入装置の供給管を貫通孔２８に挿入して供給管から空間Ｓ内に電解液を注入する。このとき、延出方向Ｙにおける第２部分３７の先端から供給管の先端が飛び出しても、樹脂部材３１の第１延出部３３ａによって、供給管の先端が第２集電体２１に接触することを抑制し、第２集電体２１が破れることを抑制できる。 (6) For example, when injecting the electrolytic solution into the space S, the supply pipe of the injection device is inserted into the through hole 28 and the electrolytic solution is injected into the space S from the supply pipe. At this time, even if the tip of the supply pipe protrudes from the tip of the second portion 37 in the extension direction Y, the tip of the supply pipe comes into contact with the second current collector 21 by the first extension portion 33a of the resin member 31. It is possible to suppress this and prevent the second current collector 21 from being broken.

なお、上記実施形態は、以下のように変更して実施することができる。上記実施形態及び以下の変更例は、技術的に矛盾しない範囲で互いに組み合わせて実施することができる。 The above embodiment can be modified and implemented as follows. The above embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.

○ 実施形態において、第２部分３７の先端は、第１樹脂部材３３における第１延出部３３ａの先端と同じ位置に位置していてもよいし、第１延出部３３ａの先端を延出方向Ｙに越えた位置に位置していてもよい。 ○ In the embodiment, the tip of the second portion 37 may be located at the same position as the tip of the first extending portion 33a in the first resin member 33, or the tip of the first extending portion 33a may be extended. It may be located at a position beyond the direction Y.

○ 実施形態において、第１部分３６が遮断部３８を有する構成であったが、筒部本体３５又は第２部分３７が遮断部３８を有する構成であってもよい。
○ 実施形態において、蓄電セル１０は、筒部材３２を有しない構成であってもよい。この場合、蓄電セル１０は、閉塞部材として樹脂部材３１のみを有する。例えば、空間Ｓ内に電解液を注入する際には、貫通孔２８に直接供給管を挿入又は押し当てし、電解液を注入する。 ○ In the embodiment, the first portion 36 has a blocking portion 38, but the tubular portion main body 35 or the second portion 37 may have a blocking portion 38.
○ In the embodiment, the power storage cell 10 may have a configuration that does not have the tubular member 32. In this case, the storage cell 10 has only the resin member 31 as the closing member. For example, when injecting the electrolytic solution into the space S, the supply pipe is directly inserted or pressed into the through hole 28, and the electrolytic solution is injected.

○ 実施形態において、閉塞部材としての樹脂部材３１が貫通孔２８の周囲に溶着される構成であったが、閉塞部材が貫通孔２８の周囲に溶着されなくてもよい。この場合、貫通孔２８に樹脂材等を充填して貫通孔２８を閉塞してもよい。 ○ In the embodiment, the resin member 31 as the closing member is welded around the through hole 28, but the closing member may not be welded around the through hole 28. In this case, the through hole 28 may be filled with a resin material or the like to close the through hole 28.

○ 実施形態において、樹脂部材３１は、第２集電体２１の第１面２１ａに溶着されていたが、第２集電体２１の第２面２１ｂに溶着されていてもよい。
○ 実施形態において、貫通孔２８は、第１集電体２０の第１未塗工部２５に設けられていてもよい。この場合、樹脂部材３１は、第１集電体２０の第１面２０ａ及び第２面２０ｂのいずれに溶着されていてもよい。 ○ In the embodiment, the resin member 31 is welded to the first surface 21a of the second current collector 21, but may be welded to the second surface 21b of the second current collector 21.
○ In the embodiment, the through hole 28 may be provided in the first uncoated portion 25 of the first current collector 20. In this case, the resin member 31 may be welded to either the first surface 20a or the second surface 20b of the first current collector 20.

○ 実施形態において、積層方向Ｚへの、突出部４０の厚みが、正極活物質層２２の厚みと負極活物質層２３の厚みの和よりも小さい構成であったが、これに限らない。例えば、突出部４０の厚みが、正極活物質層２２の厚みと負極活物質層２３の厚みの和と等しくてもよい。 ○ In the embodiment, the thickness of the protruding portion 40 in the stacking direction Z is smaller than the sum of the thickness of the positive electrode active material layer 22 and the thickness of the negative electrode active material layer 23, but the configuration is not limited to this. For example, the thickness of the protruding portion 40 may be equal to the sum of the thickness of the positive electrode active material layer 22 and the thickness of the negative electrode active material layer 23.

１…蓄電装置、１０…蓄電セル、１１…正極、１２…負極、１４…シール部材、２０…第１集電体、２０ａ…第１面、２１…第２集電体、２１ａ…第１面、２２…正極活物質層、２３…負極活物質層、２４…第１塗工部、２５…第１未塗工部、２６…第２塗工部、２７…第２未塗工部、２８…貫通孔、３０…閉塞部材、３１…樹脂部材、３２…筒部材、３６…第１部分、３７…第２部分、３８…遮断部、４０…突出部、Ｌ１…厚み、Ｌ２…厚み、Ｓ…空間、Ｙ…延出方向、Ｚ…積層方向。 1 ... power storage device, 10 ... power storage cell, 11 ... positive electrode, 12 ... negative electrode, 14 ... seal member, 20 ... first current collector, 20a ... first surface, 21 ... second current collector, 21a ... first surface , 22 ... Positive electrode active material layer, 23 ... Negative electrode active material layer, 24 ... First coated part, 25 ... First uncoated part, 26 ... Second coated part, 27 ... Second uncoated part, 28 ... through hole, 30 ... closing member, 31 ... resin member, 32 ... tubular member, 36 ... first part, 37 ... second part, 38 ... blocking part, 40 ... protruding part, L1 ... thickness, L2 ... thickness, S ... space, Y ... extension direction, Z ... stacking direction.

Claims (7)

第１集電体を有する正極と、
第２集電体を有し、前記正極に重ねて配置される負極と、
前記第１集電体と、前記第２集電体と、の間に配置され、前記第１集電体と、前記第２集電体と、に接合されたシール部材と、
前記正極と前記負極との積層方向に重なる前記第１集電体及び第２集電体と、前記シール部材と、によって画定される空間と、を備え、
前記第１集電体は、当該第１集電体の第１面において正極活物質層が存在する第１塗工部と、
当該第１集電体の第１面の露出する第１未塗工部と、を有し、
前記第２集電体は、当該第２集電体の第１面において負極活物質層が存在する第２塗工部と、
当該第２集電体の第１面の露出する第２未塗工部と、を有する蓄電セルであって、
前記第１未塗工部又は前記第２未塗工部を前記積層方向に貫通する貫通孔と、
前記貫通孔を閉塞する閉塞部材と、を有し、
前記積層方向の外面から見た平面視において、前記貫通孔は、前記シール部材よりも前記正極活物質層及び前記負極活物質層寄りに位置することを特徴とする蓄電セル。 A positive electrode with a first current collector and
A negative electrode having a second current collector and placed on top of the positive electrode,
A seal member arranged between the first current collector and the second current collector and joined to the first current collector and the second current collector.
A space defined by the first current collector and the second current collector overlapping the positive electrode and the negative electrode in the stacking direction, and the sealing member is provided.
The first current collector includes a first coating portion in which a positive electrode active material layer is present on the first surface of the first current collector.
It has an exposed first unpainted portion on the first surface of the first current collector.
The second current collector includes a second coating portion in which a negative electrode active material layer is present on the first surface of the second current collector.
A storage cell comprising an exposed second uncoated portion on the first surface of the second current collector.
A through hole that penetrates the first uncoated portion or the second uncoated portion in the stacking direction.
It has a closing member that closes the through hole, and has
A storage cell characterized in that the through hole is located closer to the positive electrode active material layer and the negative electrode active material layer than the sealing member in a plan view seen from the outer surface in the stacking direction. 前記閉塞部材は、前記貫通孔から前記積層方向に突出している突出部を含み、
前記積層方向への、前記突出部の厚みは、
前記正極活物質層の厚み、及び前記負極活物質層の厚みの和以下であることを特徴とする請求項１に記載の蓄電セル。 The closing member includes a protrusion protruding from the through hole in the stacking direction.
The thickness of the protrusion in the stacking direction is
The storage cell according to claim 1, wherein the thickness is equal to or less than the sum of the thickness of the positive electrode active material layer and the thickness of the negative electrode active material layer. 前記閉塞部材は、前記貫通孔が設けられた未塗工部における前記貫通孔の周囲に溶着されるとともに前記空間を封止する樹脂部材を含むことを特徴とする請求項１又は請求項２に記載の蓄電セル。 According to claim 1 or 2, the closing member includes a resin member that is welded around the through hole in the uncoated portion provided with the through hole and that seals the space. The storage cell described. 前記樹脂部材は、前記貫通孔が設けられた未塗工部を有する集電体の前記第１面に溶着されていることを特徴とする請求項３に記載の蓄電セル。 The storage cell according to claim 3, wherein the resin member is welded to the first surface of a current collector having an uncoated portion provided with the through hole. 前記閉塞部材は、前記貫通孔に挿入される筒部材を含み、
前記筒部材は、前記空間の内側に開口するとともに、前記筒部材を閉塞する遮断部を有していることを特徴とする請求項１～請求項４のいずれか一項に記載の蓄電セル。 The blocking member includes a tubular member inserted into the through hole.
The storage cell according to any one of claims 1 to 4, wherein the tubular member has a blocking portion that opens inside the space and closes the tubular member. 前記筒部材は、前記貫通孔より前記空間の外側に位置する第１部分を有し、
前記第１部分は、前記遮断部を有することを特徴とする請求項５に記載の蓄電セル。 The tubular member has a first portion located outside the space from the through hole.
The storage cell according to claim 5, wherein the first portion has the blocking portion. 前記筒部材と前記樹脂部材とによって前記貫通孔が閉塞され、
前記筒部材は、前記貫通孔より前記空間の内側に位置するとともに先端で開口する第２部分を有し、
前記積層方向において、前記貫通孔が設けられた未塗工部を有する集電体と前記第２部分との間には、前記樹脂部材が介在し、
前記第２部分が前記貫通孔から前記先端に延出する方向を延出方向とし、
前記第２部分の前記延出方向における先端は、前記樹脂部材の前記延出方向における先端よりも前記貫通孔寄りに位置することを特徴とする請求項４を引用する請求項５、又は請求項４を引用する請求項５を引用する請求項６に記載の蓄電セル。
The through hole is closed by the tubular member and the resin member, and the through hole is closed.
The tubular member has a second portion that is located inside the space from the through hole and opens at the tip.
In the stacking direction, the resin member is interposed between the current collector having the uncoated portion provided with the through hole and the second portion.
The direction in which the second portion extends from the through hole to the tip is defined as the extension direction.
A fifth or claim 5 quoting claim 4, wherein the tip of the second portion in the extending direction is located closer to the through hole than the tip of the resin member in the extending direction. The storage cell according to claim 6, which cites claim 5.

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