Battery

Abstract

A battery is provided in which the heat dissipation material is less likely to peel off the outer casing. [Solution] The battery of this disclosure comprises an electrode stack, an outer casing enclosing the electrode stack, and a heat dissipation material disposed between the stacked end face of the electrode stack and the outer casing. The outer casing has an inner surface facing the stacked end face of the electrode stack. The adhesion ratio is 85% or more by area. The adhesion ratio represents the ratio of the area of ​​the portion of the inner surface that is in contact with the heat dissipation material to the area of ​​the inner surface.

Description

Technical Field

[0001] The present disclosure relates to a battery.

Background Art

[0002] As a lithium-ion secondary battery with excellent safety, a solid battery is known.

[0003] Patent Document 1 discloses an all-solid-state battery cell (hereinafter also referred to as a "battery"). The battery is formed by enclosing an electrode laminate in an exterior material (hereinafter also referred to as an "outer package"). The electrode laminate includes a current collecting tab extending from an end portion. The current collecting tab is connected to a terminal led out from an end portion of the battery. Inside the outer package, a first heat transfer material (hereinafter also referred to as a "heat dissipation member") is disposed so as to contact the electrode laminate and the outer package. The heat dissipation member is disposed so as to cover an end face of the electrode laminate in the stacking direction of the electrode laminate.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, there is a risk that the heat dissipation material peels off from the outer package during use of the battery. When the heat dissipation material peels off from the outer package, heat dissipation inside the battery becomes difficult. As a result, there is a risk that problems (for example, shortening of the battery life) occur.

[0006] The present disclosure has been made in view of the above circumstances. The problem to be solved by one embodiment of the present disclosure is to provide a battery in which the heat dissipation material is difficult to peel off from the outer package.

Means for Solving the Problems

[0007] The following embodiments are included as means for solving the above problems.

[0008] <1> An electrode laminate according to the first embodiment, An outer casing that encloses the electrode stack, A heat dissipation material is disposed between the laminated end face of the electrode laminate and the outer casing, Equipped with, The outer casing has an inner surface facing the stacked end face of the electrode stack, The adhesion rate is 85% or more of the area. A battery in which the adhesion ratio represents the ratio of the area of ​​the opposing inner surface that is in contact with the heat dissipation material to the area of ​​the opposing inner surface.

[0009] In the first embodiment, the adhesion rate is 85% or more by area. As a result, the battery in the first embodiment is a battery in which the heat dissipation material is less likely to peel off from the outer casing. [Effects of the Invention]

[0010] According to this disclosure, a battery is provided in which the heat dissipation material is less likely to peel off the outer casing. [Brief explanation of the drawing]

[0011] [Figure 1] Figure 1 is a perspective view of a battery according to an embodiment of the present disclosure. [Figure 2] Figure 2 is a cross-sectional view taken along line II-II in Figure 1. [Figure 3] Figure 3 is a diagram illustrating a method for manufacturing a battery according to an embodiment of this disclosure. [Modes for carrying out the invention]

[0012] In this disclosure, a numerical range indicated using "~" means a range that includes the numbers before and after "~" as the minimum and maximum values, respectively. In numerical ranges described in stages in this disclosure, the upper or lower limit stated in one numerical range may be replaced by the upper or lower limit of another numerical range described in stages.

[0013] Embodiments of the battery of this disclosure will be described below with reference to the drawings. In the drawings, the same or corresponding parts will be denoted by the same reference numerals and will not be repeated in the description.

[0014] (1)Battery The battery 1 in the embodiment of the present disclosure is a solid-state battery. As shown in Figure 1, the battery 1 comprises an electrode stack 10, an outer casing 20, a heat dissipation material (see Figure 2) 30, an insulator 31 (see Figure 2), two negative electrode terminals 41, and two positive electrode terminals 42. The electrode stack 10 is a rectangular parallelepiped.

[0015] In this embodiment, the longitudinal direction of the main surface S10A of the electrode stack 10 is defined as the X-axis direction. The short direction of the main surface S10A of the electrode stack 10 is defined as the Y-axis direction. The thickness direction of the electrode stack 10 is defined as the Z-axis direction. The X-axis, Y-axis, and Z-axis are all orthogonal to each other. The X-axis direction is an example of an axial direction. Note that these directions do not limit the orientation of the battery when it is used.

[0016] The two negative terminals 41, the electrode stack 10, and the two positive terminals 42 are arranged in this order along the positive X-axis direction. The two negative terminals 41 and the two positive terminals 42 are electrically connected to the electrode stack 10. The heat dissipation material 30 is placed between the stacked end face S10B of the electrode stack 10 and the outer casing 20. The insulator 31 is placed between the main surface S10A of the electrode stack 10 and the outer casing 20. In other words, the heat dissipation material 30 and the insulator 31 cover the electrode stack 10 so as to electrically insulate the electrode stack 10 from the outer casing 20. The outer casing 20 encloses the electrode stack 10.

[0017] (1.1) Electrode stack The electrode stack 10 includes a plurality of unit electrode bodies 10U. The plurality of unit electrode bodies 10U are stacked along the Z-axis direction. The plurality of unit electrode bodies 10U are connected in parallel.

[0018] The laminated structure of the unit electrode body 10U is a monopolar structure. The unit electrode body 10U includes a negative electrode current collector 101, a negative electrode active material layer 102, a solid electrolyte layer 103, a positive electrode active material layer 104, a positive electrode current collector 105, a positive electrode active material layer 104, a solid electrolyte layer 103, a negative electrode active material layer 102, and a negative electrode current collector 101, which are laminated in this order along the Z-axis direction. The unit electrode body 10U may be a known unit electrode body (for example, a unit electrode body of a lithium-ion battery, a unit electrode body of a sodium-ion battery, etc.). The laminated end face S10B is composed of the end faces of the respective layers constituting the unit electrode body 10U. The laminated end face S10B is more likely to transfer the heat of the electrode laminate 10 to the exterior body 20 than the main face S10A.

[0019] (1.2) Exterior body The exterior body 20 is a metal container. As shown in FIG. 2, the exterior body 20 has an inner face S20 facing the laminated end face S10B of the electrode laminate 10. In this embodiment, the exterior body 20 is in a compressed deformation state.

[0020] (1.3) Heat dissipation material The heat dissipation material 30 electrically insulates the electrode laminate 10 and the exterior body 20. The thermal conductive insulator 32A may have a higher thermal conductivity than the insulator 31. The thermal conductivity of the heat dissipation material 30 may be 1.5 W / (m·K) to 5.0 W / (m·K). The heat dissipation material 30 may contain a known resin (for example, a thermoplastic resin, a thermosetting resin, etc.) and may contain a known thermal conductive filler. The thickness L30A (see FIG. 2) of the heat dissipation material 30 may be 0.2 mm to 3.8 mm, may be 0.5 mm to 3.5 mm, or may be 1.0 mm to 3.0 mm.

[0021] (1.4) Insulator The insulator 31 electrically insulates the electrode laminate 10 and the exterior body 20. The insulator 31 contains a known resin (for example, a thermoplastic resin, a thermosetting resin, etc.).

[0022] (1.5) Negative electrode terminal and positive electrode terminal The negative terminal 41 and positive terminal 42 are used to discharge the electricity generated in the electrode stack 10 to the outside of the battery 1. The negative terminal 41 and positive terminal 42 may be known terminals.

[0023] (1.6) Adhesion In this disclosure, the adhesion ratio is 85 area% or more, preferably 90 area% or more, more preferably 95 area% or more, and even more preferably 100 area%. The adhesion ratio represents the ratio of the area of ​​the portion R30 of the opposing inner surface S20 that is in close contact with the heat dissipation material 30 to the area of ​​the opposing inner surface S20 of the outer casing 20 (i.e., the total portion R20 of the opposing inner surface S20).

[0024] Methods for adjusting the adhesion rate to 85% or more by method 1, method 2, and method 3 include the first method, method 2, and method 3. In the first method, as shown in Figure 3, the electrode stack 10 is pressed in the D1 direction (see Figure 3) toward the opposing inner surface S20 of the outer casing 20, thereby pressing the heat dissipation material 30 against the outer casing 20. The thickness L30B of the heat dissipation material 30 before being pressed (see Figure 3) may be 0.5 mm to 4.0 mm, 0.8 mm to 3.7 mm, or 1.7 mm to 3.2 mm. The compressibility of the heat dissipation material 30 may be 5% to 60%, 10% to 50%, or 15% to 40%.

[0025] In the second method, as shown in Figure 3, the outer casing 20 is molded and the heat dissipation material 30 is pressed against the electrode laminate 10. The molding method for the outer casing 20 is not particularly limited, and examples include a method of compressing and deforming the outer casing 20 in the D2 direction (see Figure 3). The thickness L30B of the heat dissipation material 30 before pressing (see Figure 3) may be 0.5 mm to 4.0 mm, 0.8 mm to 3.7 mm, or 1.7 mm to 3.2 mm. The compressibility of the heat dissipation material 30 may be 5% to 60%, 10% to 50%, or 15% to 40%.

[0026] In the third method, the electrode stack 10 is placed inside the outer casing 20, and the heat dissipation material 30 is injected into the gap between the outer casing 20 and the electrode stack 10. The gap L30B (see Figure 3) between the outer casing 20 and the electrode stack 10 may be 0.5 mm to 4.0 mm, 0.75 mm to 3.5 mm, or 1.0 mm to 3.0 mm.

[0027] (1.7) Effects As explained with reference to Figures 1 to 3, the battery 1 comprises an electrode stack 10, an outer casing 20, and a heat dissipation material 30. The outer casing 20 has opposing inner surfaces S20. The adhesion ratio is 85% or more by area. The adhesion ratio represents the ratio of the area of ​​the portion R30 of the opposing inner surface S20 that is in contact with the heat dissipation material 30 to the total area of ​​the opposing inner surface S20. As a result, battery 1 is a battery in which the heat dissipation material 30 is less likely to peel off from the outer casing 20.

[0028] (1.8) Variation In this embodiment, the outer casing 20 is compressed and deformed so as to be sandwiched in the Y-axis direction, but the disclosure is not limited thereto. In this disclosure, the outer casing 20 may be compressed and deformed so as to be sandwiched in the Z-axis direction. The outer casing 20 may not be compressed and deformed at all. In other words, the outer surfaces of the four walls of the outer casing 20 that face the main surface S10A and the laminate end surface S10B of the electrode laminate 10 may be planar.

[0029] In this embodiment, the battery 1 includes an insulator 31, but the disclosure is not limited thereto. The battery of the disclosure may not include an insulator 31, and may instead include a heat dissipation material 30.

[0030] In this embodiment, the outer casing 20 is a metal container, but the disclosure is not limited thereto. The outer casing 20 may be a laminated outer casing. [Explanation of symbols]

[0031] 1: Battery, 10: Electrode stack, 10U: Unit electrode, 101: Negative electrode current collector, 102: Negative electrode active material layer, 103: Solid electrolyte layer, 104: Positive electrode active material layer, 105: Positive electrode current collector, 20: Outer casing, 30: Heat dissipation material, 31: Insulator, 41: Negative electrode terminal, 42: Positive electrode terminal, S10B: Stack end face

Claims

[Claim 1] Electrode stack and, An outer casing that encloses the electrode stack, A heat dissipation material is disposed between the laminated end face of the electrode laminate and the outer casing, Equipped with, The outer casing has an inner surface facing the stacked end face of the electrode stack, The adhesion rate is 85% or more by area. A battery in which the adhesion ratio represents the ratio of the area of ​​the opposing inner surface that is in contact with the heat dissipation material to the area of ​​the opposing inner surface.

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