Laminated battery

Abstract

This laminated cell is provided with: one or more cells each having an electrode laminate and a laminated film that seals the electrode laminate; and an exterior body that seals the one or more batteries. An electrode laminate in this laminated cell contains a sulfide solid electrolyte, and a space between a laminated film and an exterior is decompressed and / or filled with an inert gas.

Description

Technical Field

[0001] The invention relates to a laminated battery. Background Art

[0002] Secondary batteries such as lithium-ion secondary batteries are lightweight and can obtain high energy density. Secondary batteries are widely used as portable power sources for personal computers and mobile terminals, or vehicle driving power sources for electric vehicles (EVs), hybrid vehicles (HVs), and plug-in hybrid vehicles (PHVs). As one form of a secondary battery used as such a vehicle driving power source, a so-called laminated battery having a structure in which an electrode laminate is sealed by an outer body composed of a laminated film can be cited.

[0003] For example, Japanese Patent Application Laid-Open No. 2021-176134 discloses an all-solid-state battery in which a battery cell is housed in a laminate film.

[0004] Japanese Patent Application Laid-Open No. 2020-170583 discloses a laminated secondary battery having a laminated outer casing having a double-layer structure. Summary of the invention

[0005] In addition, solid batteries containing sulfide solid electrolytes are known. Such batteries may generate hydrogen sulfide gas, for example, due to overcharging. In a laminated battery, the generated high-temperature hydrogen sulfide gas may, for example, open the sealing portion of the laminated film and leak from the inside of the battery.

[0006] An object of the present invention is to provide a laminated battery capable of suppressing leakage of high-temperature hydrogen sulfide gas from the inside of the battery.

[0007] The present inventors have found that the above-mentioned problems can be solved by the following means.

[0008] <Method 1>

[0009] A stacked battery, comprising:

[0010] one or more batteries, the one or more batteries having an electrode stack and a stack film sealing the electrode stack; and

[0011] an outer casing that seals the one or more batteries,

[0012] The electrode stack includes a sulfide solid electrolyte,

[0013] The space between the laminated film and the outer casing is decompressed and / or filled with an inert gas.

[0014] <Method 2>

[0015] In the laminated battery according to aspect 1, the outer casing is a laminated film.

[0016] <Method 3>

[0017] In the laminate battery according to aspect 2, the sealing strength of a specific sealing portion of the laminate film as the exterior body is weaker than the sealing strength of other sealing portions.

[0018] According to the laminated battery of the present invention, it is possible to suppress leakage of high-temperature hydrogen sulfide gas from the inside of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like reference numerals represent like parts, and in which:

[0020] Figure 1 is a schematic diagram showing an example of a stacked battery of the present invention;

[0021] Figure 2 This is a schematic diagram showing an example of the stacked battery of the present invention. DETAILED DESCRIPTION

[0022] Hereinafter, embodiments of the present invention will be described in detail. In addition, the present invention is not limited to the following embodiments, and can be implemented with various modifications within the scope of the disclosed gist.

[0023] Laminated battery

[0024] The stacked battery of the present invention comprises: one or more batteries, the one or more batteries having an electrode stack and a stacked film sealing the electrode stack; and an outer casing, the outer casing sealing the one or more batteries. The electrode stack in the stacked battery of the present invention contains a sulfide solid electrolyte, and the space between the stacked film and the outer casing is decompressed and / or filled with an inert gas.

[0025] The inventors of the present invention have found that the battery sealed by the laminated film is further sealed by the outer body in such a way that the space between the laminated film and the outer body is decompressed and / or filled with an inert gas. As a result, the high-temperature hydrogen sulfide gas is not easy to leak from the inside of the battery. The reason for this is believed to be that when the high-temperature hydrogen sulfide gas leaks from the inside of the battery to the outside of the laminated film, the hydrogen sulfide gas is cooled while filling the space between the laminated film and the outer body where substantially no oxygen exists. As a result, when the hydrogen sulfide gas leaks from the space to the outside of the outer body, the hydrogen sulfide gas has reached a temperature less than the specified value.

[0026] Hereinafter, the laminated battery 1 of the present invention will be described with reference to the drawings. Figure 1 and Figure 2 1 is a schematic diagram showing an example of a laminated battery 1 of the present invention. Figure 1 and Figure 2The dimensional relationship in the figure does not reflect the actual dimensional relationship.

[0027] The laminated battery 1 of the present invention includes: one or more batteries having an electrode laminate and a laminate film 10 sealing the electrode laminate; and an exterior body sealing the one or more batteries.

[0028] It is conceivable that when high-temperature hydrogen sulfide gas is discharged, the greater the number of cells, the more heat transfer is promoted. Figure 2 As shown, a structure in which a plurality of batteries are sealed by an outer casing 11 can be adopted, and by adopting such a structure, heat transfer can be effectively suppressed. Figure 2 , the laminated battery 1 of the present invention is shown in the case where there are two batteries, but the number of batteries is not limited to this.

[0029] The outer casing 11 is not particularly limited as long as it can seal the battery. For example, the outer casing 11 may be a laminated film or an outer casing.

[0030] The electrode stack contains a sulfide solid electrolyte. For example, hydrogen sulfide gas may be generated from the sulfide solid electrolyte due to overcharge of the battery.

[0031] Examples of sulfide solid electrolytes include, but are not limited to, sulfide amorphous solid electrolytes, sulfide crystalline solid electrolytes, and argyrodite-type solid electrolytes. Specific examples of sulfide solid electrolytes include Li2S-P2S5 (Li7P3S 11 , Li3PS4, Li8P2S9, etc.), Li2S-SiS2, LiI-Li2S-SiS2, LiI-Li2S-P2S5, LiI-LiBr-Li2S-P2S5, Li2S-P2S5-GeS2 (Li 13 GeP3S 16 , Li 10 GeP2S 12 etc.), LiI-Li2S-P2O5, LiI-Li3PO4-P2S5, Li 7－x PS 6－x Cl x Etc. In addition, examples of the sulfide solid electrolyte include combinations thereof, but are not limited thereto.

[0032] The sulfide solid electrolyte may be glass or crystallized glass (glass ceramic).

[0033] In the laminated battery 1 of the present invention, the space between the laminated film 10 and the outer casing 11 is decompressed and / or filled with an inert gas. By adopting such a structure, oxygen is substantially no longer present in the space between the laminated film 10 and the outer casing 11. Even if high-temperature hydrogen sulfide gas flows into the space, the hydrogen sulfide gas can be cooled while filling the space and the temperature when leaking out of the outer casing can be reduced. In addition, as the inert gas, nitrogen, argon, etc. can be listed.

[0034] The volume of the space between the laminated film 10 and the outer casing 11 is not particularly limited as long as it is a size capable of cooling the hydrogen sulfide gas.

[0035] In the laminated battery 1 of the present invention, the sealing strength of a specific sealing portion of the laminated film as the outer body 11 may be weaker than the sealing strength of other sealing portions. By adopting such a structure, the direction of hydrogen sulfide gas leakage can be controlled. For example, the laminated battery 1 of the present invention can be used in a vehicle. In this case, by adjusting the position of the above-mentioned specific sealing portion, the hydrogen sulfide gas can be controlled to be discharged outside the vehicle.

[0036] Comparative Example 1

[0037] The battery of Comparative Example 1 was obtained by winding the electrode laminate including the sulfide solid electrolyte with the laminate film, and reducing the pressure of the space between the electrode laminate and the laminate film to a vacuum and sealing the space.

[0038] Example 1

[0039] The electrode stack containing the sulfide solid electrolyte was wound with a stacking film, and the space between the electrode stack and the stacking film was decompressed to a vacuum and sealed. Then, the stacking film was wound with the stacking film as an outer body, and the space between the inner stacking film and the outer stacking film as the outer body was decompressed to a vacuum and sealed, thereby obtaining the stacking battery of Example 1.

[0040] evaluate

[0041] The battery of the comparative example was charged by continuously passing a current of 5.5 C until high-temperature hydrogen sulfide gas leaked from the inside of the battery. The laminated battery of the example was charged under the same conditions.

[0042] result

[0043] In the laminated battery of the example, even when charging was performed under the same conditions as those of the comparative example, leakage of high-temperature hydrogen sulfide gas from the inside of the battery was not confirmed.

Claims

1. A laminated battery, wherein: The stacked battery has: One or more batteries, the one or more batteries having an electrode stack and a laminate film sealing the electrode stack; as well as an outer casing that seals the one or more batteries, The electrode stack includes a sulfide solid electrolyte, The space between the laminated film and the outer casing is decompressed and / or filled with an inert gas.

2. The laminated battery according to claim 1, wherein: The outer casing is a laminated film.

3. The laminated battery according to claim 2, wherein: The sealing strength of a specific sealing portion of the laminated film as the exterior body is weaker than the sealing strength of other sealing portions.

Images