Battery

Abstract

To provide a battery capable of improving structural efficiency while improving airtightness.SOLUTION: A battery includes an electrode laminate inside outer casings. An end face positive electrode current collector is disposed on one end face of the electrode laminate in the laminating direction of the electrode laminate. An end face negative electrode current collector is disposed on the other end face of the electrode laminate in the laminating direction of the electrode laminate. Internal current collectors are laminated inside the electrode laminate. Each internal current collector has a connecting part extending from the side of the electrode laminate. A positive terminal is disposed on one surface of the outer casing in the laminating direction of the outer casings. A negative terminal is disposed on the other surface of the outer casings in the laminating direction of the outer casings. A connection terminal is disposed on the same surface as at least one of the positive electrode terminal and the negative electrode terminal. In the inside of the outer casings, the end face positive electrode current collector and the positive electrode terminal are electrically connected, the end face negative electrode current collector and the negative electrode terminal are electrically connected, and the connection part and the connection terminal are electrically connected.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] This application relates to a battery.

Background Art

[0002] Patent Document 1 discloses a current collector plate arrangement structure of a bipolar battery in which a voltage monitoring terminal (current collector plate) extends along the stacking direction on the outer surface of the side wall sealing material or between the battery cell stack and the side wall sealing material, and an end portion thereof is disposed on the upper surface of the upper wall sealing material. According to Patent Document 1, it is described that by disposing the voltage monitoring terminal on the upper surface of the upper wall sealing material, the exclusive area of the voltage monitoring terminal on the cell side surface can be suppressed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the current collector plate arrangement structure of Patent Document 1, through holes are provided in the exterior material, and electrodes and voltage monitoring terminals are drawn out therefrom to the outside, so there is room for improvement in improving airtightness and gas barrier properties.

[0005] Therefore, in view of the above circumstances, a main object of the present disclosure is to provide a battery capable of improving airtightness and gas barrier properties while improving structural efficiency.

Means for Solving the Problems

[0006] The present disclosure provides at least the following aspects.

[0007] The first aspect is a battery having an electrode laminate inside an exterior body, wherein an end-face positive electrode current collector is disposed on one surface in the stacking direction of the electrode laminate, an end-face negative electrode current collector is disposed on the other surface in the stacking direction of the electrode laminate, an internal current collector is stacked inside the electrode laminate, the internal current collector has a connection portion drawn out from a side surface of the electrode laminate, a positive electrode terminal is disposed on one surface in the stacking direction of the exterior body, a negative electrode terminal is disposed on the other surface in the stacking direction of the exterior body, a connection terminal is disposed on the same surface as at least one of the positive electrode terminal and the negative electrode terminal, and inside the exterior body, the end-face positive electrode current collector and the positive electrode terminal are electrically connected, the end-face negative electrode current collector and the negative electrode terminal are electrically connected, and the connection portion and the connection terminal are electrically connected.

[0008] The second aspect is the battery according to the first aspect, wherein the exterior body is made of metal, and the connection terminal has a through-hole penetrating the end face of the exterior body in the stacking direction, a metal portion disposed in the through-hole, and an insulating layer disposed between the through-hole and the metal portion.

[0009] The third aspect is the battery according to the second aspect, wherein the insulating layer is disposed at an inner portion of the through-hole, and at an inner peripheral portion and an outer peripheral portion of the exterior body continuous from the through-hole.

[0010] The fourth aspect is the battery according to any one of the first to third aspects, wherein inside the exterior body, each end-face current collector and each electrode terminal are in direct contact, and the connection portion and the connection terminal are in direct contact.

Advantages of the Invention

[0011] According to the battery of the present disclosure, it is possible to improve the structural efficiency while improving the airtightness and gas barrier properties.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Mode for Carrying Out the Invention

[0013] The battery of the present disclosure will be described using the battery 100 which is one embodiment.

[0014] A plan view of the battery 100 is shown in FIG. 1. A cross-sectional view of the battery 100 cut along II-II of FIG. 1 is shown in FIG. 2(A), and an exploded cross-sectional view is shown in FIG. 2(B). As shown in FIGS. 1 and 2(A)(B), the battery 100 has an electrode laminate 50 and an exterior body 90, and includes the electrode laminate 50 inside the exterior body 90.

[0015] <Electrode laminate 50> First, the electrode laminate 50 will be described. A plan view of the electrode laminate 50 is shown in FIG. 3. A front view of the electrode laminate 50 observed from the A direction of FIG. 3 is shown in FIG. 4(A), and a side view of the electrode laminate 50 observed from the B direction of FIG. 3 is shown in FIG. 4(B).

[0016] The electrode laminate 50 has a rectangular shape when viewed in the stacking direction, and is a laminate including a current collector (a positive electrode current collector and a negative electrode current collector), a positive electrode layer, a negative electrode layer, and an electrolyte layer. In the electrode laminate 50, the number of stacked layers of each layer is not particularly limited and may be appropriately set according to the purpose. The stacking form of the electrode laminate 50 is not particularly limited, and may be a monopolar type or a bipolar type. The electrode laminate 50 may be a liquid-based battery or a solid battery. The electrode laminate 50 may be a lithium-ion battery, a sodium-ion battery, a nickel-metal hydride battery, etc. The electrode laminate 50 may be a primary battery or a secondary battery.

[0017] (Materials of the electrode laminate 50) Typical examples of the materials of each layer constituting the electrode laminate 50 will be described. However, the materials of each layer constituting the electrode laminate 50 are not limited thereto.

[0018] The current collector is a sheet-like conductive member. Examples of the current collector include metal foils such as stainless steel, iron, copper, aluminum, titanium, and nickel. The metal foil may be made of an alloy containing two or more of these metals. Further, the metal foil may be subjected to surface treatment such as predetermined plating. The current collector may be composed of a plurality of metal foils. In this case, the metal foils may be joined with an adhesive or the like, or may be joined by pressing or the like. The shape of the current collector may be rectangular. The thickness of the current collector is not particularly limited, but is, for example, 1 μm to 1 mm.

[0019] The positive electrode layer contains at least a positive electrode active material. The positive electrode active material is not particularly limited and may be appropriately selected from any materials according to the target battery performance. For example, composite oxides, metal lithium, sulfur, etc. are included. The composition of the composite oxide includes, for example, at least one of iron, manganese, titanium, nickel, cobalt, and aluminum, and lithium. Examples of the composite oxide include olivine-type lithium iron phosphate (LiFePO 4 ) etc.

[0020] The positive electrode layer may optionally contain a conductive assistant. The conductive assistant is not particularly limited and may be appropriately selected from any materials according to the desired battery performance. For example, carbon materials such as acetylene black, carbon black, and graphite can be mentioned.

[0021] The positive electrode layer may optionally contain a binder. The binder is not particularly limited and may be appropriately selected from any materials according to the desired battery performance. For example, rubber-based resins, fluoride-based resins, etc. can be mentioned.

[0022] The positive electrode layer may optionally contain a solid electrolyte. The solid electrolyte is not particularly limited and may be appropriately selected from any materials according to the desired battery performance. For example, oxide solid electrolytes, sulfide solid electrolytes, etc. can be mentioned.

[0023] The positive electrode layer may be rectangular. The thickness of the positive electrode layer is not particularly limited and is, for example, in the range of 1 μm to 1 mm. The area of the positive electrode layer may be smaller than that of the negative electrode layer. The content of each material in the positive electrode layer is not particularly limited and may be appropriately set according to the desired battery performance. Note that the positive electrode layer may contain materials other than the above-mentioned materials.

[0024] The negative electrode layer contains a negative electrode active material. The negative electrode active material is not particularly limited and may be appropriately selected from any materials according to the desired battery performance. For example, carbon materials such as graphite, artificial graphite, hard carbon, and soft carbon, metal compounds, elements capable of alloying with lithium or their compounds, etc. can be mentioned. Examples of elements capable of alloying with lithium include silicon and tin.

[0025] The negative electrode layer may optionally contain a conductive assistant. The conductive assistant is not particularly limited and may be appropriately selected from any materials according to the desired battery performance. For example, it may be appropriately selected from the conductive assistants applicable to the positive electrode layer.

[0026] The negative electrode layer may optionally contain a binder. The binder is not particularly limited and may be appropriately selected from any materials according to the intended battery performance. For example, it may be appropriately selected from the binders applicable to the positive electrode layer.

[0027] The negative electrode layer may optionally contain a solid electrolyte. The solid electrolyte is not particularly limited and may be appropriately selected from any materials according to the intended battery performance. For example, it may be appropriately selected from the solid electrolytes applicable to the positive electrode layer.

[0028] The negative electrode layer may be rectangular. The thickness of the negative electrode layer is not particularly limited and is, for example, in the range of 1 μm to 1 mm. From the viewpoint of improving the output, the area of the negative electrode layer may be larger than that of the positive electrode layer. The content of each material in the negative electrode layer is not particularly limited and may be appropriately set according to the intended battery performance. Note that the negative electrode layer may contain materials other than the above-described materials.

[0029] When the electrolyte layer is a liquid electrolyte layer, the electrolyte layer includes a separator and an electrolytic solution. The separator is mainly a porous sheet of polyolefin. The electrolytic solution is one in which a supporting salt is dissolved in a non-aqueous solvent. Examples of the non-aqueous solvent include carbonates, ethers, esters, etc. The supporting salt is, for example, LiPF 6 、LiBF 4 、lithium bis(fluorosulfonyl)imide (LiFSI), lithium bis(trifluoromethane)sulfonimide (LiTFSI), etc.

[0030] When the electrolyte layer is a solid electrolyte layer, the electrolyte layer includes a solid electrolyte. Further, the solid electrolyte layer may contain a binder. The solid electrolyte and the binder may be appropriately selected from the above-described solid electrolytes and binders.

[0031] The electrolyte layer may be rectangular. The thickness of the electrolyte layer is not particularly limited and is, for example, in the range of 1 μm to 1 mm.

[0032] (End-face positive electrode current collector 11, end-face negative electrode current collector 12, internal current collector 20) As shown in FIG. 3 and FIG. 4(A)(B), the electrode laminate 50 includes a positive electrode current collector (sometimes referred to as "end face positive electrode current collector 11" in this specification) arranged on one side in the lamination direction, and a negative electrode current collector (sometimes referred to as "end face negative electrode current collector 12" in this specification) arranged on the other side. The electrode laminate 50 also includes a current collector (sometimes referred to as "internal current collector 20" in this specification). In FIG. 4(B), layers other than the end face positive electrode current collector 11, the end face negative electrode current collector 12, and the internal current collector 20 are not specifically illustrated because they change depending on the intended battery.

[0033] The number of internal current collectors 20 is not particularly limited and may be set appropriately depending on the purpose. In FIG. 3 and FIG. 4(A)(B), a plurality of internal current collectors 20 (total of eight) are disposed inside the electrode laminate 50. The internal current collectors 20 may be positive or negative current collectors. The internal current collectors 20 may be the same type of current collector or different types of current collectors. However, since the internal electrodes 40 have a role of providing battery information to the outside as described later, they may all be composed of the same type of current collector (preferably positive current collectors). The electrode laminate 50 may also have a normal current collector other than the internal current collectors 20 inside.

[0034] One of the features of the internal current collectors 20 is that they are provided with a connection portion 22 drawn out from the side surface of the electrode laminate 50, unlike the other current collectors. FIG. 5(A) is a plan view of the internal current collector 20, and FIG. 5(B) shows a plurality of internal current collectors 20 for explaining the difference in the position of the connection portion 22.

[0035] As shown in Fig. 5(A), the internal current collector 20 includes a main body portion 21 and a connection portion 22. The main body portion 21 is a portion that is laminated inside the electrode laminate 50 and functions as a current collector. Therefore, a positive electrode layer or a negative electrode layer is laminated on the main body portion 21. The main body portion 21 has a rectangular shape. On the other hand, the connection portion 22 is a portion for providing battery information (information such as voltage and current) to the outside and has an elongated strip shape. The connection portion 22 is used, for example, as a voltage monitoring line. As shown in Figs. 3, 4(A)(B), the connection portion 22 has a form drawn out from the side surface 50a of the electrode laminate 50, and the drawn-out connection portion 22 is bent in the lamination direction. Then, the end portion of the connection portion 22 is further bent and arranged on the same surface as the end face positive electrode current collector 11. Thus, the connection portion 22 is characterized in that it extends from the side surface 50a of the electrode laminate 50 in the lamination direction and is arranged on the same surface as the end face positive electrode current collector 11.

[0036] Thus, the connection portion 22 is characterized in that it extends from the side surface of the electrode laminate 50 in the lamination direction and is arranged on the same surface as the end face current collector 20. In conventional batteries, the connection portion that functions as a voltage monitoring line has a form that is drawn out in the side surface direction. In contrast, in the battery 100, the connection portion 22 has a portion that extends from the side surface of the electrode laminate 50 in the lamination direction, whereby the area occupied by the connection portion 22 in the entire battery 100 can be reduced. Further, in Patent Document 1, an exterior material provided with a through hole for drawing out the voltage monitoring terminal to the outside is essential, and there are limitations on the structure of the exterior material. In contrast, in the battery 100, the connection portion 22 is arranged on the same surface as the end face positive electrode current collector 11, whereby the structural efficiency can be improved with a simple structure.

[0037] Here, among the connection portion 22, the portion drawn out from the side surface of the electrode laminate 50 and extending from the side surface 50a in the lamination direction is defined as an extension portion 23, and the portion arranged on the same surface as the end face positive electrode current collector 11 is defined as an end portion 24.

[0038] As shown in FIG. 5(B), the position of the connection portion 22 in the internal current collector 20 is not particularly limited. However, as shown in FIGS. 3 and 4(A)(B), each connection portion 22 drawn from a plurality of internal current collectors 20 may be arranged at a position where they do not overlap each other in the stacking direction view. Thereby, contact between the connection portions 22 can be suppressed, and the battery structure can be simplified. Also, as shown in FIG. 5(B), the length of the connection portion 22 may be arbitrarily set according to the position of the end portion 24.

[0039] Here, the fact that "the connection portion 22 is arranged on the same surface as the end face positive electrode current collector 11" will be further explained. As shown in FIGS. 3 and 4(A)(B), the end portion 24 of the connection portion 22 is arranged on the end face positive electrode current collector 11 via the end face insulating layer 30. For this reason, strictly speaking, it cannot be said that the end portion 24 of the connection portion 22 is arranged on the same surface as the end face positive electrode current collector 11. However, since the end face insulating layer 30 is a very thin layer, from the perspective of use, it can be said that they are arranged on the same surface. Therefore, "the connection portion 22 is arranged on the same surface as the end face positive electrode current collector 11" does not strictly mean that the end portion 24 of the connection portion 22 is arranged on the same surface as the end face positive electrode current collector 11, but means that the end portion 24 of the connection portion 22 may be arranged on the same surface as the end face positive electrode current collector 11 from the perspective of use.

[0040] In the electrode laminate 50, the connection portion 22 is arranged on the same surface as the end face positive electrode current collector 11, but is not limited thereto. The connection portion 22 may be arranged on the same surface as the end face negative electrode current collector 12. Also, a part of the plurality of connection portions 22 may be arranged on the same surface as the end face positive electrode current collector 11, and the rest may be arranged on the same surface as the end face negative electrode current collector 12. Therefore, the connection portion 22 may extend in the stacking direction along the side surface 50a of the electrode laminate 50 and be arranged on the same surface as at least one of the end face positive electrode current collector 11 and the end face negative electrode current collector 12.

[0041] (End face insulating layer 30) The electrode laminate 50 has an end face insulating layer 30. The end face insulating layer 30 is disposed on a part of the end face positive electrode current collector 11. And the connection part 22 (end part 24) is disposed on the end face positive electrode current collector 11 via the end face insulating layer 30, and the end part 24 and the end face positive electrode current collector 11 are insulated by the end face insulating layer 30. Thus, the end face insulating layer 30 is disposed between the end part 24 and the end face positive electrode current collector 11 and has the role of insulating them.

[0042] The material of the end face insulating layer 30 is not particularly limited, and examples thereof include polyimide, polypropylene, polyethylene, polyvinyl chloride, polytetrafluoroethylene, etc. The thickness of the end face insulating layer 30 is not particularly limited, and is, for example, 5 μm to 300 μm. The arrangement method of the end face insulating layer 30 is not particularly limited, and for example, a resin tape may be attached to the end face positive electrode current collector 11. Also, a resin sheet may be disposed between the end face positive electrode current collector 11 and the end part 24 of the connection part 22. Alternatively, a resin material may be applied to the end face positive electrode current collector 11.

[0043] Note that the end face insulating layer 30 may be disposed on the end part 24. Even if the end face insulating layer 30 is disposed on the end part 244, the end part 24 and the end face positive electrode current collector 11 can be insulated by the end face insulating layer 30. Therefore, the end face insulating layer 30 only needs to be disposed between the end part 24 and the end face positive electrode current collector 11.

[0044] (Side insulating layer 40) The electrode laminate 50 has a side insulating layer 40. The side insulating layer 40 is disposed on the side face 50a of the electrode laminate 50. And the connection part 22 (extended part 23) and the side face 50a of the electrode laminate 50 are insulated by the side insulating layer 40. Thus, the side insulating layer 40 is disposed on the side face 50a and has the role of insulating the extended part 23 and the side face 50a. Therefore, the side insulating layer 40 only needs to be disposed on at least a part of the side face 50a. The side insulating layer 40 may be disposed on the entire side face 50a.

[0045] The material of the side insulating layer 40 is not particularly limited, and examples thereof include polyimide, polypropylene, polyethylene, polyvinyl chloride, polytetrafluoroethylene, and the like. The thickness of the side insulating layer 40 is not particularly limited, and is, for example, 5 μm to 300 μm. The method of disposing the side insulating layer 40 is not particularly limited, and for example, a resin tape may be attached to the side surface 50a of the electrode laminate 50. Alternatively, a resin sheet may be disposed between the side surface 50a of the electrode laminate 50 and the extending portion 23 of the connection portion 22. Or, a resin material may be applied to the side surface 50a of the electrode laminate 50.

[0046] Note that the side insulating layer 40 may be disposed on the extending portion 23. Even if the side insulating layer 40 is disposed on the extending portion 23, the extending portion 23 and the side surface 50a of the electrode laminate 50 can be insulated by the side insulating layer 40. Therefore, the side insulating layer 40 may be disposed on at least one of the extending portion 23 and the side surface 50a of the electrode laminate 50.

[0047] (Laminated form of the electrode laminate 50) As described above, the electrode laminate 50 is a laminate including a current collector, a positive electrode layer, an electrolyte layer, and a negative electrode layer. End face current collectors 11 and 12 are laminated on both surfaces in the lamination direction of the electrode laminate 50, and a plurality of internal current collectors 20 are provided therein. Other configurations are not particularly limited. A cross-sectional view of an example of the electrode laminate 50 is shown in FIG. 6. The electrode laminate 50 shown in FIG. 6 is an electrode laminate for a bipolar lithium ion secondary battery.

[0048] As shown in FIG. 6, the electrode laminate 50 is formed by laminating a plurality of electrode bodies 56. In the electrode laminate 50, the number of the electrode bodies 56 is not particularly limited and may be appropriately set according to the purpose.

[0049] The electrode body 56 includes a positive electrode current collector 51, a negative electrode current collector 52, a positive electrode layer 53, a negative electrode layer 54, and an electrolyte layer 55. The electrode body 56 is formed by overlapping a negative electrode layer 54 disposed on the upper surface of the negative electrode current collector 52 and a positive electrode layer 53 disposed on the lower surface of the positive electrode current collector 51 with the electrolyte layer 55 interposed therebetween. And the electrode laminate 50 is formed by laminating a plurality of electrode bodies 56 so that they are connected in series.

[0050] Here, the positive electrode current collector 51 disposed on one surface of the electrode laminate 50 in the stacking direction corresponds to the end face positive electrode current collector 11, and the negative electrode current collector 52 disposed on the other surface of the stacking direction corresponds to the end face negative electrode current collector 12. Further, the positive electrode current collector 51 or the negative electrode current collector 52 included in the electrode laminate 50 corresponds to the internal current collector 20. In FIG. 6, the positive electrode current collector 51 included in the electrode laminate 50 is used as the internal current collector 20.

[0051] <Outer package 90> As shown in FIGS. 1 and 2, the outer package 90 is made of metal and has a rectangular shape when viewed in the stacking direction. The outer package 90 is a box-shaped member having a space capable of accommodating the electrode laminate 50 therein.

[0052] (Basic structure of the outer package 90) First, the basic configuration of the outer package 90 will be described. The outer package 90 has a positive electrode outer package 91 and a negative electrode outer package 92. Further, the outer package 90 has insulating resins 93 and 94.

[0053] The positive electrode outer package 91 is made of metal and has a box shape having a rectangular bottom plate 91a and four side plates 91b sharing each side of the bottom plate 91a. That is, the positive electrode outer package 91 has a U-shaped cross section. Further, the surface of the positive electrode outer package 91 facing the bottom plate 91a is open. The negative electrode outer package 92 is made of metal and has a box shape having a rectangular bottom plate 92a and four side plates 92b sharing each side of the bottom plate 92a. That is, the negative electrode outer package 92 has a U-shaped cross section. Further, the surface of the negative electrode outer package 92 facing the bottom plate 92a is open. Then, the positive electrode outer package 91 and the negative electrode outer package 92 are overlapped so that their bottom plates face each other in the stacking direction and their side plates face each other in a direction orthogonal to the stacking direction. Thereby, a space capable of accommodating the electrode laminate 50 can be formed inside the outer package 90.

[0054] Here, the bottom plate 12a of the positive electrode exterior body 91 is formed to have a larger area than the bottom plate 92a of the negative electrode exterior body 92. Therefore, when the electrode laminate 50 is housed in the exterior body 90, the side plate 92b of the negative electrode exterior body 92 is disposed inside the side plate 91b of the positive electrode exterior body 91.

[0055] The metal constituting the positive electrode exterior body 91 and the negative electrode exterior body 92 is not particularly limited, and examples thereof include aluminum, aluminum alloy, stainless steel, copper, copper alloy, and nickel steel. The thicknesses of the positive electrode exterior body 91 and the negative electrode exterior body 92 are not particularly limited, and are, for example, 0.05 mm or more and 2.0 mm or less.

[0056] The resin 93 is disposed between the side surface of the electrode laminate 50 and the side plate 92b of the positive electrode exterior body 91. Thereby, the side surface of the electrode laminate 50 and the side plate 92b of the positive electrode exterior body 91 are insulated from each other, and they can be fixed. The resin 94 is disposed between the side plate 91b of the positive electrode exterior body 91 and the side plate 92b of the negative electrode exterior body 92. Thereby, the side plate 91b of the positive electrode exterior body 91 and the side plate 92b of the negative electrode exterior body 92 are insulated from each other, and they can be fixed.

[0057] Such a basic configuration of the outer layer body 90 is described, for example, in Japanese Patent Application No. 2023-006850.

[0058] (Characteristic Structure of Exterior Body 90) Subsequently, the characteristic portions of the exterior body 90 will be described. The exterior body 90 includes a positive electrode terminal 61 disposed on one surface in the stacking direction, a negative electrode terminal 62 disposed on the other surface in the stacking direction, and a plurality of connection terminals 70 disposed on the same surface as the positive electrode terminal 61.

[0059] The positive electrode terminal 61 is the bottom plate 91a of the positive electrode exterior body 91 and is the part exposed to the outside. Typically, an insulating layer may be disposed on a part of the inner surface of the bottom plate 91a of the positive electrode exterior body 91 other than the part in contact with the end face positive electrode current collector 11, and an insulating layer 95 may be disposed on a part of the outer surface other than the part connected to the outside (see FIG. 1, not shown in FIG. 2). In this case, the positive electrode terminal 61 is the part of the bottom plate 91a of the positive electrode exterior body 91 where the insulating layer is not disposed and is exposed to the outside. The same applies to the negative electrode terminal 62. The negative electrode terminal 62 is the bottom plate 92a of the negative electrode exterior body 92 and is the part exposed to the outside. Typically, an insulating layer may be disposed on a part of the inner surface of the bottom plate 92a of the negative electrode exterior body 92 other than the part in contact with the end face negative electrode current collector 12, and an insulating layer may be disposed on a part of the outer surface other than the part connected to the outside. In this case, the negative electrode terminal 62 is the part of the bottom plate 92a of the negative electrode exterior body 92 where the insulating layer is not disposed and is exposed to the outside.

[0060] Note that both surfaces of the side plate 91b of the positive electrode exterior body 91 and the side plate 92b of the negative electrode exterior body 92 may be covered with an insulating layer. Thereby, the inner surface of the side plate of the exterior body 90 (the inner surface of the side plate 92b of the negative electrode exterior body 92) and the electrode laminate 50 can be insulated. Also, the outer surface of the side plate of the exterior body 90 (the outer surface of the side plate 91b of the positive electrode exterior body 91) and an external member can be insulated.

[0061] Here, the positive electrode terminal 61 is in direct contact with and electrically connected to the end face positive electrode current collector 11 of the electrode laminate 50 inside the exterior body 90. The negative electrode terminal 62 is in direct contact with and electrically connected to the end face negative electrode current collector 12 of the electrode laminate 50 inside the exterior body 90. Therefore, both end faces in the stacking direction of the exterior body 90 function as terminals. In this way, since the positive electrode terminal 61 and the negative electrode terminal 62 are electrically connected to the end face positive electrode current collector 11 and the end face negative electrode current collector 12 of the electrode laminate 50 inside the exterior body 90, airtightness and gas barrier properties are ensured.

[0062] Note that, from the perspective of improving structural efficiency, the positive electrode terminal 61 and the end face positive electrode current collector 11 are in direct contact and electrically connected inside the outer package 90, but it is not limited to this form. The positive electrode terminal 61 and the end face positive electrode current collector 11 may be indirectly electrically connected inside the outer package 90 via a conductive member or the like. Similarly, from the perspective of improving structural efficiency, the negative electrode terminal 62 and the end face negative electrode current collector 12 are in direct contact and electrically connected inside the outer package 90, but it is not limited to this form. The negative electrode terminal 62 and the end face negative electrode current collector 12 may be indirectly electrically connected inside the outer package 90 via a conductive member or the like.

[0063] The connection terminal 70 is electrically connected to the connection portion 42 of the electrode laminate 50 and has a role of providing information of the electrode laminate 50 to the outside. The connection terminal 70 is disposed on the bottom plate 91a of the positive electrode outer package 91. That is, the connection terminal 70 is disposed on the same surface as the positive electrode terminal 61. The connection terminal 70 is in direct contact with and electrically connected to the end portion 44 of the connection portion 42 inside the outer package 90. The number of connection terminals 70 corresponds to the number of connection portions 42, and each connection terminal 70 is connected to each connection portion 42.

[0064] A specific configuration of the connection terminal 70 will be described. FIG. 7 shows a partial cross-sectional view focusing on the connection terminal 70. As shown in FIG. 7, the connection terminal 70 has a through hole 71 that penetrates the end face of the outer package 90 (the bottom plate 91a of the positive electrode outer package 91) in the stacking direction, a metal portion 72 disposed in the through hole 71, and an insulating layer 73 disposed between the through hole 71 and the metal portion 72.

[0065] The through hole 71 penetrates the end face of the outer package 90 (the bottom plate 91a of the positive electrode outer package 91) in the stacking direction. The size of the through hole 71 is not particularly limited and may be appropriately set according to the purpose. For example, the size of the through hole 71 may be 0.05 mm to 1.0 mm. The shape of the through hole 71 is not particularly limited, but is typically circular.

[0066] The metal part 72 is a part that is in direct contact with and electrically connected to the end 44 of the connection part 42 inside the exterior body 90. By connecting the metal part 72 to the end 44 of the connection part 42 inside the exterior body 90, airtightness and gas barrier properties are ensured. The metal constituting the metal part 72 is not particularly limited. For example, copper, gold, silver, nickel, chromium, etc. can be mentioned. The metal part 72 may be arranged only in the through-hole 71, but from the viewpoint of enhancing connectivity, in addition to the inside of the through-hole 71, it may also be arranged in the peripheral part of the inner surface and the peripheral part of the outer surface of the exterior body 90 (the bottom plate 91a of the positive electrode exterior body 91) continuous from the through-hole 71.

[0067] Incidentally, from the viewpoint of improving structural efficiency, the metal part 72 and the end 44 of the connection part 42 are in direct contact and electrically connected inside the exterior body 90, but it is not limited to this form. The metal part 72 and the end 44 of the connection part 42 may be indirectly electrically connected inside the exterior body 90 via a conductive member or the like.

[0068] The insulating layer 73 has the role of insulating the metal part 72 and the exterior body 90 (positive electrode exterior body 91). The insulating layer 73 is arranged between the exterior body 90 (positive electrode exterior body 91) and the metal part 72. When the metal part 72 is arranged only inside the through-hole 71, the insulating layer 73 may be provided only in the inner part of the through-hole 71. When the metal part 72 is arranged inside the through-hole 71 and in the peripheral part of the inner surface and the peripheral part of the outer surface of the exterior body 90 (the bottom plate 91a of the positive electrode exterior body 91) continuous from the through-hole 71, the insulating layer 73 may be arranged in the inner part of the through-hole 73 and in the inner peripheral part and the outer peripheral part of the exterior body 90 continuous from the through-hole 71. Typically, as described above, in the bottom plate 91a of the positive electrode exterior body 91, the insulating layer 95 is arranged in the part other than the positive electrode terminal 61. Therefore, typically, the insulating layer 73 constitutes a part of the insulating layer 95 and is arranged in the inner part of the through-hole 73 and in the inner peripheral part and the outer peripheral part of the exterior body 90 continuous from the through-hole 71.

[0069] The material of the insulating layer 73 is not particularly limited, and examples include polyimide, polypropylene, polyethylene, polyvinyl chloride, polytetrafluoroethylene, etc.

[0070] The method of providing the connection terminal 70 on the exterior body 90 is not particularly limited, and for example, the following methods can be mentioned. FIG. 8 shows an example of the method of providing the connection terminal 70 on the exterior body 90. FIG. 8 is a cross-sectional view of the positive electrode exterior body 91. First, a through hole 71 is provided at a predetermined position on the bottom plate 91a of the positive electrode exterior body 91. Subsequently, the portion of the bottom plate 91a that will become the positive electrode terminal 61 is covered with a predetermined masking member M, and an insulating layer is disposed on the other portions. Then, a metal portion 72 is disposed in the through hole 71 provided with the insulating layer 72. Examples of the method of disposing the metal portion 72 can include plating treatment.

[0071] (Effect) In the current collector plate arrangement structure described in Patent Document 1, through holes are provided in the exterior material, and electrodes and voltage monitoring terminals are drawn out from there to the outside.

[0072] On the other hand, in the battery 100, inside the exterior body 90, the end face positive electrode current collector 11 and the positive electrode terminal 61 are electrically connected, the end face negative electrode current collector 12 and the negative electrode terminal 62 are electrically connected, and the connection portion 42 and the connection terminal 70 are electrically connected. Therefore, the battery 100 ensures airtightness and gas barrier properties, and the airtightness and gas barrier properties are improved compared to the prior art. Also, in the battery 100, the end face electrode terminal and the connection terminal are arranged on the same plane. Therefore, similar to Patent Document 1, the structural efficiency can be improved compared to the prior art.

[0073] As described above, the battery of the present disclosure has been described using one embodiment. According to the battery of the present disclosure, it is possible to improve the airtightness, gas barrier properties, and structural efficiency.

Explanation of Reference Numerals

[0074] 11 End face positive electrode current collector 12 End face negative electrode current collector 20 Internal current collector 21 Main body portion 22 Connection portion 23 Extension portion 24 End portion 30 End face insulating layer 40 Side insulating layer 50 Electrode laminate 50a Side 61 Positive electrode terminal 62 Negative electrode terminal 70 Connection part 71 Through-hole 72 Metal part 73 Insulating layer 90 Outer package 91 Positive electrode outer package 92 Negative electrode outer package 93, 94 Resin 95 Insulating layer 100 Battery

Claims

1. A battery including an electrode laminate inside an exterior body, An end surface positive electrode current collector is disposed on one surface in the stacking direction of the electrode stack, an end surface negative electrode current collector is disposed on the other surface in the stacking direction of the electrode stack; an internal current collector is laminated inside the electrode laminate, the internal current collector has a connection portion drawn out from a side surface of the electrode stack, A positive electrode terminal is disposed on one surface of the exterior body in the lamination direction, a negative electrode terminal is disposed on the other surface of the exterior body in the stacking direction; a connection terminal is disposed on the same surface as at least one of the positive terminal and the negative terminal; Within the exterior body, the end surface positive electrode collector and the positive electrode terminal are electrically connected, the end surface negative electrode collector and the negative electrode terminal are electrically connected, and the connection portion and the connection terminal are electrically connected. battery.

2. The exterior body is made of metal, The connection terminal has a through hole penetrating an end surface of the exterior body in a stacking direction, a metal portion disposed in the through hole, and an insulating layer disposed between the through hole and the metal portion.

10. The battery of claim 1.

3. The battery according to claim 2 , wherein the insulating layer is disposed on an inner portion of the through hole and on an inner peripheral portion and an outer peripheral portion of an exterior body continuing from the through hole.

4. The battery according to any one of claims 1 to 3, wherein inside the exterior body, the end surface positive electrode collector and the positive electrode terminal are in direct contact, the end surface negative electrode collector and the negative electrode terminal are in direct contact, and the connection portion and the connection terminal are in direct contact.

Images