Collector terminal for battery and battery

Abstract

To provide a collector terminal for a battery which can secure the electronic conduction and also can suppress heat transfer to an electrode laminate body and a sealing part of a laminate film when the power terminal is joined to an external connection terminal, and a battery having the collector terminal.SOLUTION: A collector terminal 10 for a battery includes: a collector foil joint unit 11 for joining a collector foil of an electrode multilayer body; a peripheral part 12 for fusing a laminate film; and an external connection terminal joint part 13 for joining to an external connection terminal; and a low-heat conduction region 14 between the peripheral part 12 and the external connection terminal 13. A battery 1 of the present disclosure includes: an electrode multilayer body 20; the collector terminal 10 of the present disclosure electrically connected to the collector foil of the electrode laminate body; and a laminate film 30 for sealing the collector terminal and the electrode multilayer body.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a current collector terminal for a battery and a battery.

Background Art

[0002] A laminated battery (also called a pouch battery) in which an electrode laminate is sealed with a laminated film is known.

[0003] For example, Patent Document 1 includes an electrode laminate in which sheet-like electrode elements are laminated, and an exterior body that houses the electrode laminate therein. The exterior body includes a cylindrical laminated film exterior body that covers at least both end faces and a pair of opposing side faces in the lamination direction of the electrode laminate, and an inner lid disposed at an opening of the laminated film exterior body. The electrode laminate is sealed inside the exterior body by joining the outer peripheral portion of the inner lid and the laminated film exterior body that overlaps the outer peripheral portion of the inner lid. A secondary battery is disclosed.

[0004] Further, Patent Document 1 discloses that the outer peripheral portion of the inner lid and the laminated film exterior body can be joined by heat welding (fusion welding).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In a laminated battery, there is also known a battery in which the current collecting terminal itself has a shape like the inner lid described in Patent Document 1, that is, a shape having a predetermined volume, and the current collecting terminal seals the electrode laminate together with the laminated film. In a battery having such a current collecting terminal, when an external connection terminal is joined to the current collecting terminal in order to form a battery module, heat during joining may move from the current collecting terminal to the electrode laminate. As a result, the performance of the battery is impaired.

[0007] Further, when the above heat moves to the sealing portion of the laminated film where the current collecting terminal and the laminated film are fused, manufacturing defects such as poor sealing may occur.

[0008] On the other hand, in order not to impair the performance of the battery, it is necessary to ensure the electronic conductivity in the current collecting terminal.

[0009] An object of the present disclosure is to provide a current collecting terminal for a battery that can suppress the transfer of heat to the electrode laminate and the sealing portion of the laminated film during joining with an external connection terminal while ensuring electronic conductivity, and a battery having such a current collecting terminal.

Means for Solving the Problems

[0010] The present inventors have found that the above problems can be solved by the following means. <Aspect 1> A current collecting foil joining portion for joining a current collecting foil of an electrode laminate, A peripheral portion for fusing a laminated film, and An external connection terminal joining portion for joining with an external connection terminal, A current collecting terminal for a battery having a low heat conduction region between the peripheral portion and the external connection terminal joining portion. A current collecting terminal for a battery. <Aspect 2> The current collecting terminal according to Aspect 1, wherein the low heat conduction region is formed by a through hole. <Aspect 3> The current collector terminal according to aspect 2, wherein the low thermal conductivity region is formed by filling the through hole with a material having a lower thermal conductivity than the other portions of the current collector terminal. <Aspect 4> An electrode laminate The current collector terminal according to any one of aspects 1 to 3, which is electrically connected to the current collector foil of the electrode laminate, and A laminate film that seals the electrode laminate together with the current collector terminal A battery having the same.

Advantages of the Invention

[0011] According to the present disclosure, it is possible to provide a current collector terminal for a battery that can suppress heat transfer to the electrode laminate and the sealing portion of the laminate film when joined to an external connection terminal while ensuring electronic conductivity, and a battery having such a current collector terminal.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0013] Hereinafter, embodiments of the present disclosure will be described in detail. Note that the present disclosure is not limited to the following embodiments, and can be variously modified and implemented within the scope of the gist of the disclosure.

[0014] Hereinafter, the current collector terminal for a battery and the battery of the present disclosure will be described with reference to the drawings. Note that the dimensional relationships in the drawings do not reflect the actual dimensional relationships.

[0015] 《Current Collector Terminal for a Battery》 As illustrated in FIG. 1, the current collector terminal 10 for a battery of the present disclosure has a current collector foil bonding portion 11 for bonding the current collector foil of the electrode laminate 20, a peripheral portion 12 for fusing the laminate film, and an external connection terminal bonding portion 13 for bonding to an external connection terminal, and has a low heat conduction region 14 between the peripheral portion 12 and the external connection terminal bonding portion 13.

[0016] As described above, when bonding an external connection terminal to the current collector terminal to form a battery module, the heat during bonding may move from the current collector terminal to the electrode laminate and the sealing portion of the laminate film where the current collector terminal and the laminate film are fused.

[0017] Regarding this, the present inventors have found that by providing a low heat conduction region in the current collector terminal, the thermal conductivity of the current collector terminal can be reduced, and thereby the transfer of heat from the current collector terminal to the electrode laminate and the sealing portion of the laminate film when bonding the external connection terminal to the current collector terminal can be suppressed.

[0018] As illustrated in FIG. 1, the shape of the current collector terminal 10 for a battery of the present disclosure may be, for example, a rectangular parallelepiped having a top surface portion, a bottom surface portion facing the top surface portion, and four side surface portions connecting the top surface portion and the bottom surface portion. In this case, the low heat conduction region 14 may be, for example, a region formed to communicate the top surface portion and the bottom surface portion. The current collector foil bonding portion 11 may be any one of the four side surface portions. The external connection terminal 13 may be the side surface portion facing the current collector foil bonding portion 11 among the four side surface portions. The peripheral portion 12 may be a portion formed from a portion between the low heat conduction region 14 and the side surface portion that is the current collector foil bonding portion among the top surface portion and the bottom surface portion, and a side surface portion that is not the current collector foil bonding portion and the external connection terminal bonding portion.

[0019] Note that the shape of the current collector terminal is not limited to a rectangular parallelepiped. For example, the shape of the top surface portion of the current collector terminal includes quadrilaterals such as a square, a rectangle, a rhombus, a trapezoid, and a parallelogram. Further, the shape of the top surface portion may be a polygon other than a quadrilateral, or may be a shape having a curve such as a circle. Also, the shape of the bottom surface portion may be the same as the shape of the top surface portion. The shape of the side surface portion is not particularly limited, and examples thereof include quadrilaterals such as a square, a rectangle, a rhombus, a trapezoid, and a parallelogram.

[0020] The low thermal conductivity region 14 may be formed by a through hole. According to such a configuration, the thermal conductivity of the current collector terminal can be made particularly low, and the effect of suppressing the transfer of heat from the current collector terminal to the sealing portion of the electrode laminate and the laminate film is likely to be achieved. Further, by reducing the weight of the current collector terminal, it is possible to contribute to the weight reduction of the battery.

[0021] The low thermal conductivity region 14 may be formed by filling a through hole with a material having a lower thermal conductivity than other portions of the current collector terminal. According to such a configuration, it is possible to reduce the thermal conductivity of the current collector terminal while maintaining the strength of the current collector terminal.

[0022] Regarding the present disclosure, the material of the current collector terminal is not particularly limited as long as it is a material having a current collecting function, and for example, it can be the same metal material as the positive current collector and the negative current collector constituting the electrode laminate. Specifically, examples of the material of the current collector terminal include metal materials such as aluminum.

[0023] When the material other than the thermal conductivity region of the current collector terminal is a metal, the material constituting the low thermal conductivity region is not particularly limited, and examples thereof include resins.

[0024] The volume of the low thermal conductivity region is not particularly limited, and can be appropriately designed according to the volume of the current collector terminal and the amount of heat when an external connection terminal is joined to the current collector terminal.

[0025] In FIGS. 1 and 2, the low thermal conductivity region is shown as a rectangular parallelepiped, but the shape of the low thermal conductivity region is not particularly limited. Examples of the planar shape of the low thermal conductivity region include quadrilaterals such as squares, rectangles, rhombuses, trapezoids, and parallelograms. Further, the planar shape of the low thermal conductivity region may be a polygon other than a quadrilateral, or may be a shape having a curve such as a circle (see FIG. 3).

[0026] The number of low thermal conductivity regions is not particularly limited and may be one or more (see FIG. 3).

[0027] As illustrated in FIG. 4, the low thermal conductivity region may be formed such that its end contacts the side surface of the current collecting terminal. That is, a part of the side surface of the current collecting terminal may be missing to form the low thermal conductivity region.

[0028] The method for manufacturing the current collecting terminal having the through hole as the low thermal conductivity region is not particularly limited, and examples thereof include a method of punching with a press machine, a drill, etc. so as to have a desired shape, size, etc.

[0029] As described above, in the case where the low thermal conductivity region is formed by the through hole, the aspect in which the low thermal conductivity region is formed to extend in the stacking direction of the electrode laminate has been described. However, the direction in which the low thermal conductivity region extends is not particularly limited, and for example, it may be formed to extend in the plane direction of the electrode laminate.

[0030] 《Battery》 As illustrated in FIG. 5, the battery 1 of the present disclosure includes an electrode laminate 20, the current collecting terminal 10 of the present disclosure electrically connected to the current collecting foil of the electrode laminate, and a laminate film 30 that seals the electrode laminate together with the current collecting terminal.

[0031] The battery of the present disclosure may be a liquid battery or a solid battery. In the present disclosure, the "solid battery" means a battery using at least a solid electrolyte as an electrolyte. Therefore, the solid battery may use a combination of a solid electrolyte and a liquid electrolyte as the electrolyte. Further, the solid battery of the present disclosure may be an all-solid battery, that is, a battery using only a solid electrolyte as an electrolyte.

[0032] The battery of the present disclosure may be, for example, a lithium-ion secondary battery. Examples of the use of the battery include power sources for vehicles such as hybrid vehicles (HEVs), plug-in hybrid vehicles (PHEVs), battery electric vehicles (BEVs), gasoline vehicles, and diesel vehicles. In particular, it is preferably used as a driving power source for a hybrid vehicle (HEV), a plug-in hybrid vehicle (PHEV), or a battery electric vehicle (BEV). Further, the battery in the present disclosure may be used as a power source for a moving body other than a vehicle (for example, a railway, a ship, an aircraft), or may be used as a power source for an electrical product such as an information processing device.

[0033] <Electrode laminate> The electrode laminate 20 functions as a power generation element of the battery. The shape of the electrode laminate is not particularly limited. For example, it may have a top surface portion, a bottom surface portion facing the top surface portion, and four side surface portions connecting the top surface portion and the bottom surface portion. The shape of the top surface portion is not particularly limited. For example, quadrilaterals such as a square, a rectangle, a rhombus, a trapezoid, and a parallelogram can be mentioned. Further, the shape of the top surface portion may be a polygon other than a quadrilateral, or may be a shape having a curve such as a circle. Further, the shape of the bottom surface portion is the same as that of the top surface portion. The shape of the side surface portion is not particularly limited. For example, quadrilaterals such as a square, a rectangle, a rhombus, a trapezoid, and a parallelogram can be mentioned.

[0034] The electrode laminate may have a positive electrode current collector layer, a positive electrode active material layer, an electrolyte layer, a negative electrode active material layer, and a negative electrode current collector layer in this order. Materials commonly used in the field of batteries can be used for each layer.

[0035] <Laminate film> The laminate film 30 seals the electrode laminate 20 together with the current collecting terminal 10. Specifically, the laminate film may wind the electrode laminate and the current collecting terminal, and seal the electrode laminate together with the current collecting terminal. Further, the laminate film may be composed of a first film and a second film. In this case, the first and second films may sandwich the electrode laminate and the current collecting terminal from above and below in the stacking direction of the electrode laminate, and seal the electrode laminate together with the current collecting terminal.

[0036] The laminate film may have a fusion resin layer, a metal layer, and a protective resin layer in this order along the thickness direction. Examples of the material of the fusion resin layer include olefin resins such as polypropylene (PP) and polyethylene (PE). Examples of the material of the metal layer include aluminum, aluminum alloy, and stainless steel. Examples of the material of the protective resin layer include polyethylene terephthalate (PET) and nylon. The thickness of the fusion resin layer is, for example, 40 μm or more and 100 μm or less. The thickness of the metal layer may be, for example, 30 μm or more and 60 μm or less. The thickness of the protective resin layer may be, for example, 20 μm or more and 60 μm or less. The thickness of the laminate film may be, for example, 80 μm or more and 250 μm or less.

[0037] 〈Current Collecting Terminal〉 Regarding the current collecting terminal, reference can be made to the above description of the current collecting terminal for a battery of the present disclosure.

Explanation of Reference Numerals

[0038] 1 Battery 10 Current Collecting Terminal for Battery 11 Current Collecting Foil Joint 12 Peripheral Portion 13 External Connection Terminal Joint 14 Low Heat Conduction Region 20 Electrode Laminate 30 Laminate Film

Claims

1. A current collector foil joint for joining a current collector foil of an electrode laminate, a peripheral portion for fusing a laminate film, and an external connection terminal joint for joining to an external connection terminal, having a low heat conduction region between the peripheral portion and the external connection terminal joint, a current collector terminal for a battery.

2. The current collector terminal according to claim 1, wherein the low heat conduction region is formed by a through hole.

3. The current collector terminal according to claim 2, wherein the low heat conduction region is formed by filling the through hole with a material having lower thermal conductivity than other portions of the current collector terminal.

4. An electrode laminate, the current collector terminal according to any one of claims 1 to 3 electrically connected to the current collector foil of the electrode laminate, and a laminate film sealing the electrode laminate together with the current collector terminal A battery having.

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