Batteries and battery systems

Abstract

This utility model relates to a battery having an electrode body, a casing, and an insulating component. The electrode body has a positive electrode layer, an electrolyte layer, and a negative electrode layer, and at least one of the positive electrode layer, the electrolyte layer, and the negative electrode layer contains a sulfide solid electrolyte. The insulating component is disposed between the electrode body and the casing. The insulating component contains a sulfide solid electrolyte. Using this utility model, it is possible to detect the entry of external gas into the casing at an early stage.

Description

Technical Field

[0001] This utility model relates to a battery and a battery system. Background Technology

[0002] Japanese Patent Application Publication No. 2023-037971 discloses an all-solid-state battery in which an electrode stack having a positive electrode, a negative electrode and a solid electrolyte layer disposed between the positive electrode and the negative electrode is sealed inside an outer casing, and a composition containing a desiccant and a resin is disposed in the void portion inside the outer casing.

[0003] In sulfide-based all-solid-state batteries, the solid electrolyte reacts with moisture in the atmosphere to produce hydrogen sulfide. If the battery cell casing fails to seal due to impact or foreign objects, there is a risk of solid electrolyte deactivation, leading to reduced battery performance and the release of flammable hydrogen sulfide. Utility Model Content

[0004] This invention was made in view of the above-mentioned actual situation. The technical problem to be solved is how to provide a battery that can detect the entry of external gas into the casing at an early stage.

[0005] The technical means used to solve the above-mentioned technical problems include the following methods.

[0006] The first embodiment is a battery comprising: an electrode body having a positive electrode layer, an electrolyte layer and a negative electrode layer, wherein at least one of the positive electrode layer, the electrolyte layer and the negative electrode layer contains a sulfide solid electrolyte; a casing; and an insulating component disposed between the electrode body and the casing, wherein the insulating component contains a sulfide solid electrolyte.

[0007] The second method is the battery according to the first method, wherein the sulfide solid electrolyte contained in the insulating component is a sulfide solid electrolyte of the sulfide type.

[0008] The third method is the battery described in the first or second method, wherein the battery is a solid-state battery.

[0009] The fourth method is a battery according to any one of the first to third methods, wherein a laminated casing is used as the casing.

[0010] The fifth approach is a battery system having a battery as described in any of the first to fourth approaches, a hydrogen sulfide detection unit, and a judgment unit, wherein the judgment unit determines the generation of hydrogen sulfide based on the detection result of the hydrogen sulfide detection unit.

[0011] According to this invention, a battery can be provided that can detect the entry of external gas into the casing at an early stage. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of a cross-section of an existing battery.

[0013] Figure 2 This is a cross-sectional schematic diagram of an example of the battery involved in this utility model.

[0014] Figure 3 This is a cross-sectional schematic diagram of another example of the battery involved in this utility model.

[0015] Figure 4 This is a cross-sectional schematic diagram of another example of the battery involved in this utility model.

[0016] Figure 5 This is a cross-sectional schematic diagram of another example of the battery involved in this utility model. Detailed Implementation

[0017] The battery of this utility model is described in detail below using the accompanying drawings. The following figures are schematic representations, and the size and shape of each part are appropriately exaggerated for ease of understanding.

[0018] The battery of this invention comprises an electrode body, a casing, and an insulating component. The electrode body has a positive electrode layer, an electrolyte layer, and a negative electrode layer, and at least one of the positive electrode layer, the electrolyte layer, and the negative electrode layer contains a sulfide solid electrolyte. The insulating component is disposed between the electrode body and the casing. The insulating component contains a sulfide solid electrolyte.

[0019] Furthermore, the battery of this invention is preferably a solid-state battery. A solid-state battery has a multi-layer structure comprising a positive electrode, a solid electrolyte layer, and a negative electrode. Solid-state batteries include so-called all-solid-state batteries that use a solid electrolyte as the electrolyte, and the solid electrolyte may also contain an electrolyte solution comprising less than 10% by mass relative to the total electrolyte volume. Additionally, the solid electrolyte may be a composite solid electrolyte comprising an inorganic solid electrolyte and a polymer electrolyte.

[0020] The battery of this invention contains a sulfide solid electrolyte in the insulating component. The sulfide solid electrolyte reacts with moisture in the atmosphere to rapidly release a small amount of hydrogen sulfide, thus enabling the use of a hydrogen sulfide sensor to detect contact between the inside of the casing and the external gas (sealing failure).

[0021] Furthermore, since early detection of the aforementioned seal failure is possible, detection can be performed before the electrode body comes into contact with external gas, thus suppressing the degradation of battery performance.

[0022] The battery of this invention has an insulating component disposed between the electrode body and the casing, the insulating component comprising a sulfide solid electrolyte.

[0023] As a sulfide solid electrolyte, a known sulfide solid electrolyte can be used, such as either a glass ceramic or an Argyrodite type solid electrolyte.

[0024] Sulfide solid electrolytes may contain, for example, compounds ranging from LiI-LiBr-Li3PS4, Li2S-SiS2, LiI-Li2S-SiS2, LiI-Li2S-P2S5, LiI-Li2O-Li2S-P2S5, LiI-Li2S-P2O5, LiI-Li3PO4-P2S5, Li2S-GeS2-P2S5, Li2S-P2S5, Li 10 GeP2S 12 Li4P2S6, Li7P3S 11 Choose at least one from the group consisting of Li3PS4, Li7PS6, and Li6PS5X (X = Cl, Br, I).

[0025] From the perspective of early detection of sealing failure, the preferred sulfide solid electrolyte is the silver-germanium sulfide solid electrolyte.

[0026] The sulfide-germanium ore type solid electrolyte contains Li, P, S, and X (where X is a halogen). Element X can be F, Cl, Br, or I. There can be one or more elements of X. As a compositional formula, for example, it can distinguish the types of element X as X... 1 Element (halogen 1), X 2 The element (halogen 2), represented as Li 7-y-z PS 6-y- z X 1 y X 2 z (y≧0, z≧0, 1≦y+z≦1.8). Specifically, Li6PS5Cl, Li6PS5Br, Li6PS5I, and Li6PS5Cl can be listed. 0.75 Br 0.25 Li6PS5Cl 0.5 Br 0.5 Li 5.75 PS 4.75 Cl 1.25 Li 5.5 PS 4.5 Cl 1.5 And so on, but not limited to these.

[0027] The shape and size of the insulating components can be appropriately selected based on the shape and size of the battery, electrodes, casing, etc.

[0028] Specifically, the preferred insulating components are insulating components made of sulfide solid electrolytes, insulating components made of resin containing sulfide solid electrolytes, and insulating components having a laminated structure of resin and sulfide solid electrolytes.

[0029] In addition, in insulating components with a layered structure, it is preferable that the resin layer is on the electrode body side and the sulfide solid electrolyte layer is on the shell side.

[0030] There are no particular restrictions on the resins used as insulating components. Examples include polyethylene (PE), polypropylene (PP), polyester, polyamide, butadiene rubber (BR), butene rubber (IIR), acrylate butadiene rubber (ABR), styrene butadiene rubber (SBR), polyvinylidene fluoride (PVdF), polytetrafluoroethylene (PTFE), and polyimide (PI). A single resin can be used alone, or two or more resins can be used in combination.

[0031] In addition, there are no particular restrictions on the resin content in the insulating components, and it can be selected appropriately.

[0032] The battery of this invention has an electrode body, which has a positive electrode layer, an electrolyte layer and a negative electrode layer, and at least one of the positive electrode layer, the electrolyte layer and the negative electrode layer contains a sulfide solid electrolyte.

[0033] The sulfide solid electrolyte used in the electrode body can be the aforementioned sulfide solid electrolyte.

[0034] The positive electrode layer is preferably composed of a current-collecting foil and a positive electrode active material layer.

[0035] The negative electrode layer is preferably composed of a current collector foil and a negative electrode active material layer.

[0036] As the current collector foil, materials such as aluminum foil, copper foil, nickel foil, titanium foil, or stainless steel foil can be used. The thickness of the current collector foil can be, for example, 1 μm to 100 μm.

[0037] Here, the thickness of each layer, such as the current collector foil, the positive electrode active material layer, and the negative electrode active material layer, is the average value of the measurements taken at 10 randomly selected locations.

[0038] The positive electrode active material layer contains a positive electrode active material capable of absorbing and releasing charge carriers such as lithium ions. As the positive electrode active material, materials that can be used as positive electrode active materials in lithium-ion secondary batteries, such as lithium composite metal oxides with layered rock salt structures, spinel-structured metal oxides, and polyanionic compounds, can be employed. Furthermore, two or more positive electrode active materials can be used in combination. In this embodiment, the positive electrode active material layer contains olivine-type lithium iron phosphate (LiFePO4) as a composite oxide.

[0039] The negative electrode active material layer is not particularly limited, and can be any monomer, alloy, or compound capable of absorbing and releasing charge carriers such as lithium ions. Examples of negative electrode active materials include Li or carbon, metal compounds, elements or compounds capable of alloying with lithium, etc. Examples of carbon include natural graphite, artificial graphite, hard carbon (difficult-to-graphitize carbon), or soft carbon (easily-graphitize carbon). Examples of artificial graphite include highly oriented graphite, mesophase carbon microspheres, etc. Examples of elements capable of alloying with lithium include silicon and tin. In this embodiment, the negative electrode active material layer comprises graphite as a carbon-based material.

[0040] The positive and negative active material layers may further include conductive additives, binders, electrolytes (polymer matrix, ion-conducting polymer, electrolyte solution, etc.) to improve conductivity, and electrolyte support salts (lithium salts) to improve ion conductivity. The components or their proportions in the positive and negative active material layers, as well as their thicknesses, are not particularly limited and can be appropriately referenced to existing well-known understandings regarding lithium-ion secondary batteries.

[0041] The thicknesses of the positive and negative active material layers are, for example, 2 μm to 150 μm. The positive or negative active material layers can be formed on the surface of the current collector foil using existing known methods such as roll coating. To improve the thermal stability of the positive or negative active material layers, a heat-resistant layer can be provided on the surface of the current collector foil (single-sided or double-sided), or on the surface of the positive or negative active material layers. The heat-resistant layer may contain, for example, inorganic particles and a binder, and may also contain additives such as tackifiers.

[0042] Conductive additives are added to improve the conductivity of the positive or negative electrode active material layer. Examples of conductive additives include acetylene black, carbon black, and graphite.

[0043] Examples of adhesives include fluorinated resins such as polyvinylidene fluoride, polytetrafluoroethylene, and fluororubber; thermoplastic resins such as polypropylene and polyethylene; imide resins such as polyimide and polyamide-imide; resins containing alkoxysilyl groups; acrylic resins such as poly(meth)acrylic acid; styrene-butadiene rubber (SBR); alginates such as carboxymethyl cellulose, sodium alginate, and ammonium alginate; water-soluble cellulose ester crosslinkers; and starch-acrylic acid graft polymers. These adhesives can be used alone or in combination. Solvents such as water and N-methyl-2-pyrrolidone (NMP) can be used.

[0044] The electrolyte layer (also known as a "separator") is positioned between the positive and negative electrode layers. It prevents short circuits caused by contact between the two electrodes and allows charge carriers such as lithium ions to pass through, thus isolating the positive and negative electrode layers. The electrolyte layer prevents short circuits between adjacent bipolar electrodes when bipolar electrodes are stacked.

[0045] The electrolyte layer can be, for example, a porous sheet or nonwoven fabric containing a polymer that absorbs and retains the electrolyte. Examples of materials constituting the electrolyte layer include polypropylene, polyethylene, polyolefins, and polyester. The separator can have a single-layer or multi-layer structure. Multi-layer structures may include, for example, an adhesive layer and a ceramic layer as a heat-resistant layer. The electrolyte layer can be impregnated with an electrolyte, or it can be composed of a polymeric electrolyte or an inorganic electrolyte.

[0046] Examples of electrolytes impregnated in an electrolyte layer include liquid electrolytes (electrolytes) containing a non-aqueous solvent and an electrolyte salt dissolved in the non-aqueous solvent, or polymeric gel electrolytes containing an electrolyte retained in a polymer matrix.

[0047] When the electrolyte layer contains an electrolyte, known lithium salts such as LiClO4, LiAsF6, LiPF6, LiBF4, LiCF3SO3, LiN(FSO2)2, and LiN(CF3SO2)2 can be used as the electrolyte salt. Furthermore, known solvents such as cyclic carbonates, cyclic esters, chain carbonates, chain esters, and ethers can be used as the non-aqueous solvent. Additionally, two or more of these known solvent materials can be used in combination.

[0048] The battery according to this utility model has a casing.

[0049] There are no particular restrictions on the shape and size of the housing; it can be chosen appropriately according to expectations. Examples include coin-shaped (button-shaped) housings, can-shaped housings, and laminated housings.

[0050] The casing material can be any known material, as long as it is chosen appropriately based on the shape of the casing and the purpose of the battery.

[0051] The shell of a tank can also be a square-shaped shell.

[0052] The laminated housing preferably has at least a metal layer, and a fusion resin layer is formed on the side of the metal layer opposite to the side member. Alternatively, the laminated housing may have a protective layer on the side of the metal layer opposite to the side member.

[0053] Materials used for the fusion bonding resin layer include, for example, olefin-based resins such as polypropylene (PP) and polyethylene (PE). Materials used for the metal layer include, for example, aluminum, aluminum alloys, and stainless steel. Materials used for the protective layer include, for example, polyethylene terephthalate (PET) and nylon.

[0054] The thickness of the fusion-bonded resin layer is, for example, 40 μm or more and 100 μm or less. The thickness of the metal layer is, for example, 30 μm or more and 60 μm or less. The thickness of the protective layer is, for example, 20 μm or more and 60 μm or less. The overall thickness of the laminated housing is, for example, 70 μm or more and 220 μm or less.

[0055] The battery of this invention may have side components.

[0056] As a side member, a current collector side member can be listed. A current collector side member refers to a side member that has a current collector portion at least in one part. The current collector portion is electrically connected to, for example, the tabs in the aforementioned battery. The current collector side member can be entirely composed of the current collector portion or only partially composed of it. As a material for the side member, metals such as stainless steel (SUS) can be listed. The shape of the side member is not particularly limited; for example, it can be a cuboid.

[0057] The battery described above may have a resin layer (e.g., an electrode diaphragm) disposed on the surfaces of a pair of sides of the side member. The resin layer is disposed such that it covers a portion of the surface of the side member and is located between the side member and the housing.

[0058] Materials used for the resin layer include, for example, olefin-based resins such as polypropylene (PP) and polyethylene (PE). The thickness of the resin layer is, for example, 40 μm or more and 100 μm or less.

[0059] The battery of this invention is typically a lithium-ion secondary battery. Examples of its applications include power sources for vehicles such as hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), battery electric vehicles (BEVs), gasoline vehicles, and diesel vehicles. It is particularly preferred for use as a power source for driving hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), or battery electric vehicles (BEVs). Furthermore, batteries manufactured using the method described in this invention can be used as power sources for mobile bodies other than vehicles (e.g., railway vehicles, ships, and aircraft), and also as power sources for electrical appliances such as information processing devices.

[0060] The following description uses the accompanying drawings to illustrate specific embodiments of the battery involved in this utility model.

[0061] Figure 1 This is a schematic diagram of a cross-section of an existing battery.

[0062] Figure 1 The battery 1 shown has a coin-shaped (also called a button-shaped) casing consisting of an outer can 3, a sealing can 4, and a gasket 5. It is a battery in the shape of a granular electrode body 2 containing a positive electrode layer 21, a negative electrode layer 22, and an electrolyte layer 23 between the positive and negative electrode layers 21 and 22. Specifically, in battery 1, the sealing can 4 is fitted into the opening of the outer can 3 via the gasket 5, and the opening of the outer can 3 is tightened inwards, thereby abutting the gasket 5 against the sealing can 4, sealing the opening of the outer can 3, and creating a sealed internal structure. Furthermore, the outer can 3 also serves as the positive terminal, and the sealing can 4 also serves as the negative terminal. Additionally, a composition 6 containing a desiccant and resin is placed between the electrode body 2 and the sealing can 4.

[0063] exist Figure 1 In the battery 1 shown, the sealing failure cannot be detected early in the event of a sealing failure; it can only be detected after the battery performance has deteriorated.

[0064] Figure 2 This is a cross-sectional schematic diagram of an example of the battery of this utility model.

[0065] Figure 2 In the battery 1 shown, there is an insulating component 7 containing a sulfide solid electrolyte between the electrode body 2 and the outer can 3, the sealing can 4, and the gasket 5, which are coin-shaped shells.

[0066] exist Figure 2 In the battery 1 shown, in the event of a seal failure, hydrogen sulfide is generated by the reaction of the sulfide solid electrolyte contained in the insulating component 7 with moisture in the air. This can be detected in the early stage of the seal failure, where it does not affect the electrode body 2 or has a minor impact and the battery performance is not reduced.

[0067] In addition, as Figure 2 Insulating component 7 and the following described in detail Figures 3-5 Among the insulating components 7 and 36, preferably examples include insulating components made of sulfide solid electrolytes, insulating components made of resin containing sulfide solid electrolytes, and insulating components having a laminated structure of resin and sulfide solid electrolytes.

[0068] Figure 3 This is a cross-sectional schematic diagram of another example of the battery of this utility model.

[0069] Figure 3 The battery 1 shown has an insulating component 7 containing a sulfide solid electrolyte between the electrode body 2 and the outer can 3 (which serves as a coin-shaped casing), the sealing can 4, and the gasket 5. Additionally, a composition 6 containing a desiccant and a resin is provided between the insulating component 7 and the sealing can 4. The desiccant can be a known desiccant.

[0070] exist Figure 2 and Figure 3 In the above description, the parts other than those mentioned above are consistent with... Figure 1 same.

[0071] Figure 4 This is a cross-sectional schematic diagram of another example of the battery of this utility model.

[0072] Figure 4 The battery 30 shown is a square-shaped can battery with an insulating component 36 containing a sulfide solid electrolyte between the electrode body 32 and the can-shaped casing 34. The can-shaped casing 34 also has a positive electrode 38 and a negative electrode 40. The positive electrode 38 and the negative electrode 40 are connected to the electrode body 32.

[0073] Figure 5 This is a cross-sectional schematic diagram of another example of the battery of this utility model.

[0074] Figure 5 The battery 30 shown is a laminated battery, with an insulating component 36 containing a sulfide solid electrolyte between the electrode body 32 and the laminated casing 42. The laminated casing 42 also has a positive electrode 38 and a negative electrode 40. The positive electrode 38 and the negative electrode 40 are connected to the electrode body 32.

[0075] The battery system of this utility model includes: the battery of this utility model, a hydrogen sulfide detection unit, and a judgment unit that judges the generation of hydrogen sulfide based on the detection result of the hydrogen sulfide detection unit.

[0076] As a hydrogen sulfide detection unit, there are no special restrictions, and it is permissible to use known sensors for detecting hydrogen sulfide.

[0077] The judgment unit acquires the detection value from the hydrogen sulfide detection unit and determines whether hydrogen sulfide has been generated, i.e., whether a sealing failure has occurred in the battery, based on whether the detection value is above a threshold. A computer can be used in the judgment unit. If the judgment unit determines that the detection value is above the threshold, it can notify the user of the battery system by issuing a warning or other means.

[0078] This utility model is not limited to the above-described embodiments. The above-described embodiments are illustrative, and any method having a substantially the same technical concept and achieving the same effect as the technical solution described in this utility model is included within the technical scope of this utility model.

Claims

1. A battery, characterized in that, have: An electrode body has a positive electrode layer, an electrolyte layer and a negative electrode layer, and at least one of the positive electrode layer, the electrolyte layer and the negative electrode layer contains a sulfide solid electrolyte; case; and An insulating component is disposed between the electrode body and the housing. The insulating component contains a sulfide solid electrolyte.

2. The battery according to claim 1, characterized in that, The sulfide solid electrolyte contained in the insulating component is a sulfide solid electrolyte of the silver-germanium sulfide type.

3. The battery according to claim 1, characterized in that, The battery is a solid-state battery.

4. The battery according to claim 1, characterized in that, The shell has a laminated shell as the shell.

5. A battery system, characterized in that, have: The battery according to claim 1; Hydrogen sulfide detection department; and The judgment unit determines the generation of hydrogen sulfide based on the detection results of the hydrogen sulfide detection unit.

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