Battery and electric device

Abstract

Disclosed in the present invention are a battery and an electric device. The battery comprises: a blocking member; a housing provided with a storage cavity and a first through hole, wherein the storage cavity is in communication with the first through hole; an adhesive layer disposed between the blocking member and the housing, wherein two sides of the adhesive layer are respectively bonded to the blocking member and the housing, and the blocking member closes the first through hole; and an expansion member disposed between the blocking member and the housing, wherein two sides of the expansion member are respectively connected to the blocking member and the housing, and the expansion member is configured such that when the expansion member thermally expands, the expansion force of the expansion member is greater than the bonding force of the adhesive layer. The battery of the present invention allows pressure to be effectively and quickly released.

Description

Batteries and electrical equipment

[0001] Cross-reference to related applications

[0002] This application is based on and claims priority to Chinese Patent Application No. 202411911757.6, filed on December 24, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This invention relates to the field of battery technology, and in particular to a battery and an electrical device. Background Technology

[0004] In related technologies, when a battery encounters internal short circuits, overcharging, over-discharging, external impacts, or high temperatures, a large amount of heat and gas may be generated inside the battery, potentially leading to an explosion. To effectively prevent battery explosions, an explosion-proof valve can be installed. Specifically, when the internal pressure of the battery becomes too high, the explosion-proof valve can release the gas inside the battery, thereby effectively preventing an explosion.

[0005] Furthermore, existing battery pressure relief methods involve a pressure relief hole on the casing, with a metal component glued to the casing to seal the hole. When the internal pressure of the battery becomes too high, the internal temperature also increases, causing the adhesive to fail and allowing the pressure relief hole to open and release pressure. However, the adhesive retains high bonding strength even when melted, meaning the metal component still blocks the pressure relief hole, preventing the gas inside the battery from escaping quickly. Summary of the Invention

[0006] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a battery capable of effectively and rapidly releasing pressure.

[0007] The present invention also proposes an electrical device.

[0008] A battery according to a first aspect embodiment of the present invention comprises:

[0009] Sealing components;

[0010] The housing has a storage cavity and a first through hole, the storage cavity and the first through hole being in communication;

[0011] An adhesive layer is disposed between the sealing member and the housing, with both sides of the adhesive layer bonded to the sealing member and the housing respectively, and the sealing member sealing the first through hole;

[0012] An expansion member is disposed between the sealing member and the housing, with its two sides connected to the sealing member and the housing respectively. The expansion member is configured such that when the expansion member expands due to heat, the expansion force of the expansion member is greater than the adhesive force of the adhesive layer.

[0013] The battery according to embodiments of the present invention has at least the following beneficial effects: An adhesive layer is disposed between the sealing member and the housing, which can fix the sealing member to the housing, thereby achieving the sealing member sealing the first through hole. When the internal pressure of the battery increases, since the expansion member is located between the housing and the sealing member, and the expansion force of the expansion member is greater than the adhesive force of the adhesive layer when heated, the expansion member can, under heating conditions, disconnect the connection between the sealing member and the housing through its own expansion force, thereby allowing the internal pressure of the housing to be released quickly. Specifically, the battery can effectively and quickly release pressure.

[0014] According to some embodiments of the battery of the present invention, the adhesive layer is provided with a second through hole, and the first through hole and the second through hole are connected.

[0015] According to some embodiments of the battery of the present invention, the expansion member is provided with a third through hole, and the adhesive layer is disposed in the third through hole.

[0016] According to some embodiments of the present invention, the adhesive layer includes a first adhesive layer and a second adhesive layer, the side of the first adhesive layer opposite to the second adhesive layer is bonded to the housing, the side of the second adhesive layer opposite to the first adhesive layer is bonded to the sealing member, and the melting point of the first adhesive layer is lower than the melting point of the second adhesive layer.

[0017] According to some embodiments of the present invention, the area of ​​the first through hole is S1, the area of ​​the adhesive layer is S2, the area of ​​the expansion member is S3, and 0.1≤(S2+S3):S1≤10.

[0018] According to some embodiments of the present invention, the area of ​​the adhesive layer is S2, the area of ​​the expansion member is S3, and 0.1≤S2:S3≤10.

[0019] According to some embodiments of the battery, the expansion temperature of the expansion member is T1, the melting point of the adhesive layer is T2, and T2-T1≥5℃.

[0020] According to some embodiments of the battery, the expansion temperature of the expansion member is T1, where 95℃≤T1≤110℃.

[0021] According to some embodiments of the battery, the melting point of the adhesive layer is T2, where 100℃≤T2≤130℃.

[0022] According to some embodiments of the present invention, the battery housing includes a metal component and a main body. The main body is provided with the storage cavity and the first through hole. The metal component is provided with a fourth through hole, which communicates with the first through hole. One side of the metal component is welded to the main body, and the other side of the metal component is connected to the adhesive layer. Along the thickness direction of the metal component, the projected area of ​​the metal component is D1, and the projected area of ​​the sealing component is D2, where D1 > D2.

[0023] According to some embodiments of the present invention, the battery further includes terminals and cells, the cells being disposed in the storage cavity, the terminals being insulatedly connected to the housing, and the terminals and the cells being electrically connected, the sealing member and the terminals being located on the same side of the housing, the height of the terminals protruding relative to the housing being L1, the height of the sealing member protruding relative to the housing being L2, and L2 ≤ L1.

[0024] An electrical appliance according to a second aspect embodiment of the present invention includes a battery according to any one of the first aspect embodiments.

[0025] The electrical device according to embodiments of the present invention has at least the following beneficial effects: An adhesive layer is disposed between the sealing member and the housing, which can fix the sealing member to the housing, thereby sealing the first through hole. When the internal pressure of the battery increases, since the expansion member is located between the housing and the sealing member, and the expansion force of the expansion member is greater than the adhesive force of the adhesive layer when heated, the expansion member can, under heating conditions, disconnect the connection between the sealing member and the housing through its own expansion force, thereby allowing the internal pressure of the housing to be released quickly. Specifically, the battery can effectively and quickly release pressure. Furthermore, the electrical device with this battery has higher safety.

[0026] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0027] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0028] Figure 1 is a partial schematic diagram of the battery according to the first embodiment of the present invention;

[0029] Figure 2 is a schematic diagram of a partial explosion of a battery according to some embodiments of the present invention;

[0030] Figure 3 is a partial schematic diagram of the battery according to the second embodiment of the present invention;

[0031] Figure 4 is a partial schematic diagram of the battery according to the third embodiment of the present invention;

[0032] Figure 5 is a schematic diagram of a battery according to some embodiments of the present invention.

[0033] Reference numerals: 100 for sealing component, 200 for housing, 210 for first through hole, 220 for metal component, 221 for fourth through hole, 230 for main body, 300 for adhesive layer, 310 for second through hole, 400 for expansion component, 410 for third through hole, and 500 for pole. Detailed Implementation

[0034] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0035] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0036] In the description of this invention, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0037] In the description of this invention, unless otherwise explicitly defined, terms such as "setting," "installing," and "connecting" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0038] In the description of this invention, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0039] The battery can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.

[0040] A battery typically consists of a cell. The cell includes a positive electrode, a negative electrode, and a separator. During charging and discharging, active ions (such as lithium ions) move back and forth between the positive and negative electrodes, inserting and releasing. The separator, positioned between the positive and negative electrodes, prevents short circuits while allowing active ions to pass through.

[0041] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0042] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material is disposed on either or both of the two opposite surfaces of the positive current collector.

[0043] As an example, the positive electrode current collector can be a metal foil or a composite current collector. For example, as a metal foil, it can be aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium, etc. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0044] As an example, the positive electrode active material may include at least one of the following materials: lithium phosphate, lithium transition metal oxide, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphate may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites. Examples of lithium transition metal oxide may include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (such as LiNi). 1 / 3 Co 1 / 3 Mn 1 / 3O2 (also known as NCM333), LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM523), LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM211), LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM622), LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM811), lithium nickel cobalt aluminum oxide (such as LiNi) 0.85 Co 0.15 Al 0.05 At least one of O2 and its modified compounds.

[0045] In some embodiments, the positive electrode can be a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloys, etc. When foamed metal is used as the positive electrode, the surface of the foamed metal may or may not contain a positive electrode active material. As an example, lithium source material, potassium metal, or sodium metal can also be filled and / or deposited within the foamed metal, where the lithium source material is lithium metal and / or a lithium-rich material.

[0046] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0047] As an example, the negative electrode current collector can be a metal foil, a foamed metal, or a composite current collector. For example, as a metal foil, it can be silver-treated aluminum or stainless steel, stainless steel, copper, aluminum, nickel, carbon electrode, nickel, or titanium, etc. Foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloy, etc. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors can be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0048] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0049] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active material is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0050] As an example, the negative electrode active material may be a negative electrode active material known in the art for use in batteries. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as negative electrode active materials for batteries may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0051] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0052] In some implementations, the battery cell also includes an isolation element disposed between the positive and negative terminals.

[0053] In some embodiments, the separator is a separator membrane. The separator membrane can be of various types, and any known porous separator membrane with good chemical and mechanical stability can be selected.

[0054] As an example, the material of the separator may include at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator may be a single-layer film or a multi-layer composite film. When the separator is a multi-layer composite film, the materials of each layer may be the same or different. The separator may be a separate component located between the positive and negative electrodes, or it may be attached to the surfaces of the positive and negative electrodes.

[0055] In some embodiments, the separator is a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrodes, serving both to transport ions and to isolate the positive and negative electrodes.

[0056] In some embodiments, the battery also includes an electrolyte that acts as a conductor of ions between the positive and negative electrodes. The electrolyte can be liquid, gel-like, or solid. Liquid electrolytes include an electrolyte salt and a solvent.

[0057] In some embodiments, the electrolyte salt may include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalate borate, lithium dioxalate borate, lithium difluorodioxalate phosphate, and lithium tetrafluorooxalate phosphate.

[0058] In some embodiments, the solvent may include at least one selected from ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butyl carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent may also be an ether solvent. Ether solvents may include one or more selected from ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyl tetrahydrofuran, diphenyl ether, and crown ethers.

[0059] Among them, the gel electrolyte includes a polymer as the electrolyte backbone network, combined with an ionic liquid - lithium salt.

[0060] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0061] As an example, polymer solid electrolytes can be polyether (polyoxyethylene), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymers, polyionic liquids-lithium salts, cellulose, etc.

[0062] As an example, inorganic solid electrolytes may include one or more of the following: oxide solid electrolytes (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON thin film), sulfide solid electrolytes (crystalline lithium superconducting ion conductor (lithium germanium phosphate sulfide, silver sulfide germanium ore), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0063] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0064] In some implementations, the battery cell has a wound structure. The positive and negative electrode plates are wound into a wound structure.

[0065] In some implementations, the battery cell has a laminated structure.

[0066] As an example, multiple positive and negative electrodes can be set, and multiple positive and multiple negative electrodes can be stacked alternately.

[0067] As an example, multiple positive electrode plates can be provided, and negative electrode plates can be folded to form multiple stacked folded segments, with a positive electrode plate sandwiched between adjacent folded segments.

[0068] As an example, both the positive and negative electrode plates are folded to form multiple stacked folded segments.

[0069] As an example, multiple separators can be provided, each positioned between any adjacent positive or negative electrode plates.

[0070] As an example, the separators can be continuously arranged, either by folding or rolling between any adjacent positive or negative electrode plates.

[0071] In some implementations, the battery cell can be cylindrical, flat, or polygonal, etc.

[0072] In some implementations, the battery cell is provided with tabs that allow current to be drawn out of the cell. The tabs include a positive tab and a negative tab.

[0073] In some embodiments, the battery may include a casing. The casing is used to encapsulate components such as the battery cell and electrolyte. The casing may be made of steel, aluminum, plastic (such as polypropylene), composite metal (such as copper-aluminum composite), or aluminum-plastic film, etc.

[0074] As an example, the battery can be a cylindrical battery, a prismatic battery, a pouch battery, or a battery of other shapes. Prismatic batteries include, but are not limited to, square-shell batteries, blade-shaped batteries, and multi-prismatic batteries, such as hexagonal prismatic batteries.

[0075] The battery mentioned in the embodiments of this application refers to a single physical module that includes one or more batteries to provide higher voltage and capacity.

[0076] In some embodiments, the battery can be a battery module, and when there are multiple batteries, the multiple batteries are arranged and fixed to form a battery module.

[0077] In some embodiments, the battery may be a battery pack, which includes a housing and a battery, with the battery or battery module housed within the housing.

[0078] In some embodiments, the housing may be part of the vehicle's chassis structure. For example, a portion of the housing may be at least a part of the vehicle's floor, or a portion of the housing may be at least a part of the vehicle's crossbeams and longitudinal beams.

[0079] This application provides an electrical device that uses a battery as a power source. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0080] In related technologies, when a battery encounters internal short circuits, overcharging, over-discharging, external impacts, or high temperatures, a large amount of heat and gas may be generated inside the battery, potentially leading to an explosion. To effectively prevent battery explosions, an explosion-proof valve can be installed. Specifically, when the internal pressure of the battery becomes too high, the explosion-proof valve can release the gas inside the battery, thereby effectively preventing an explosion.

[0081] Furthermore, existing battery pressure relief methods involve a pressure relief hole on the casing, with a metal component glued to the casing to seal the hole. When the internal pressure of the battery is too high, the internal temperature is also high, causing the adhesive to fail and allowing the pressure relief hole to open for pressure relief. However, the adhesive still has high bonding strength when it melts, which means the metal component will still block the pressure relief hole, preventing the gas inside the battery from escaping quickly. Therefore, this application proposes a new battery design.

[0082] Referring to Figures 1 to 3, in some embodiments, the battery includes: a battery cell, a sealing member 100, a housing 200, an adhesive layer 300, and an expansion member 400. The housing 200 has a storage cavity and a first through hole 210, which are connected. The shape of the housing 200 can be rectangular, square, cylindrical, or triangular, etc., and the shape of the housing 200 is not specifically limited. The housing 200 can be connected to the negative terminal of the battery cell, thereby becoming energized. The first through hole 210 can be used not only for pressure relief but also for injecting electrolyte into the storage cavity. The adhesive layer 300 is disposed between the sealing member 100 and the housing 200, with both sides of the adhesive layer 300 bonded to the sealing member 100 and the housing 200 respectively. The sealing member 100 seals the first through hole 210. That is, through the bonding of the adhesive layer 300, the sealing member 100 can seal the first through hole 210. In addition, when the internal pressure and heat of the battery are too high, the adhesive layer 300 melts due to the heat, the viscosity decreases, and the sealing component 100 cannot block the first through hole 210, which allows the gas in the storage cavity to escape.

[0083] An expansion member 400 is disposed between the sealing member 100 and the housing 200. The two sides of the expansion member 400 are connected to the sealing member 100 and the housing 200, respectively. The expansion member 400 is configured such that when it expands due to heat, its expansion force is greater than the adhesive force of the adhesive layer 300. Specifically, the adhesive layer 300 is disposed between the sealing member 100 and the housing 200. The adhesive layer 300 can fix the sealing member 100 to the housing 200, thereby sealing the first through hole 210. When the internal pressure of the battery increases, because the expansion member 400 is located between the housing 200 and the sealing member 100, and its expansion force is greater than the adhesive force of the adhesive layer 300 when it expands due to heat, the expansion member 400 can, under heat, disconnect the connection between the sealing member 100 and the housing 200 through its own expansion force, allowing the internal pressure of the housing 200 to be released as quickly as possible. Specifically, the battery can effectively and quickly release pressure.

[0084] Furthermore, in this application, the pressure relief effect is achieved by connecting the sealing element 100 and the housing 200 through the adhesive layer 300. However, because the adhesive layer 300 remains sticky when heated and melts, it can cause some adhesion between the sealing element 100 and the housing 200, preventing the first through hole 210 from being fully opened immediately for gas release. By further adding the expansion element 400, the expansion force of the expansion element 400 after heating is greater than the adhesive force. The expansion element 400 will accelerate the opening of the first through hole 210, thereby achieving rapid pressure relief.

[0085] The expander 400 can be made of a thermally expandable microsphere foaming agent, which is a type of tiny spherical particle capable of volume expansion within a specific temperature range. It typically consists of a thermoplastic polymer shell and an internally encapsulated low-boiling-point hydrocarbon compound. This unique structure allows the microspheres to expand upon heating. Thermally expandable microsphere foaming agents may include polyvinyl alcohol (PVA) microspheres, polystyrene (PS) microspheres, polyacrylate (PA) microspheres, etc.

[0086] The adhesive layer 300 can be made of hot melt adhesive. Hot melt adhesive can be rapidly plasticized and cured after heating, making it ideal for applications requiring rapid assembly. In battery manufacturing, the use of hot melt adhesive can significantly shorten production cycles and improve production efficiency.

[0087] Furthermore, the shapes of the first through hole 210, the adhesive layer 300, and the sealing element 100 are not specifically limited. For example, the shapes of the first through hole 210, the adhesive layer 300, and the sealing element 100 can be rectangles, squares, circles, ovals, or irregular polygons, etc.

[0088] Furthermore, the adhesive layer 300 can be disposed between the housing 200 and the sealing member 100 in various ways. For example, the adhesive layer 300 can cover the first through hole 210, and then the housing 200 and the sealing member 100 are bonded to both sides of the adhesive layer 300 respectively; or, the adhesive layer 300 can be provided with a second through hole 310, which is connected to the first through hole 210, and the adhesive layer 300 is distributed at the edge of the first through hole 210. Specifically, referring to Figures 1 to 3, in some embodiments, the adhesive layer 300 is provided with a second through hole 310, and the first through hole 210 and the second through hole 310 are connected. The way in which the first through hole 210 and the second through hole 310 are connected can accelerate the separation of the housing 200 and the sealing member 100. Specifically, when the internal temperature of the housing 200 increases, the temperature of the housing 200 will rise, and then the housing 200 will conduct heat to the side of the adhesive layer 300 facing away from the sealing member 100. The adhesion between the housing 200 and the adhesive layer 300 will weaken. High-temperature gas will also enter the second through hole 310 through the first through hole 210, causing the sealing member 100 to be heated. The adhesion between the sealing member 100 and the adhesive layer 300 will weaken. In this way, the sealing member 100 can quickly separate from the housing 200, realizing rapid pressure relief of the battery.

[0089] Further referring to Figures 1 to 3, in some embodiments, the expansion member 400 is provided with a third through hole 410, and the adhesive layer 300 is disposed in the third through hole 410. In battery manufacturing, the process can involve placing the cured adhesive layer 300 between the sealing member 100 and the housing 200, then hot-pressing the sealing member 100 and the housing 200 to melt the adhesive layer 300, which then bonds the sealing member 100 and the housing 200. Afterward, the expansion member 400 is placed into the gap between the housing 200 and the sealing member 100, surrounding the edge of the adhesive layer 300. This facilitates battery manufacturing and effectively improves battery manufacturing efficiency. If, during battery manufacturing, the expansion member 400 is placed between the housing 200 and the sealing member 100 first, then when the adhesive layer 300 is hot-pressed, the expansion member 400 may expand due to heat, thus failing to improve the battery manufacturing yield.

[0090] Furthermore, in some embodiments, the adhesive layer 300 includes a first adhesive layer and a second adhesive layer. The side of the first adhesive layer opposite to the second adhesive layer is bonded to the housing 200, and the side of the second adhesive layer opposite to the first adhesive layer is bonded to the sealing member 100. The melting point of the first adhesive layer is lower than that of the second adhesive layer. Specifically, since the melting point of the first adhesive layer is lower than that of the second adhesive layer, when the internal temperature of the housing 200 is high, the first adhesive layer melts rapidly upon heating, reducing the adhesion between the first adhesive layer and the housing 200. However, since the melting point of the second adhesive layer is higher than that of the first adhesive layer, the second adhesive layer can continue to adhere to the sealing member 100 after heating. Thus, when the battery runs out of control, the adhesive layer 300 can adhere to the sealing member 100 and detach from the housing 200 together with the sealing member 100, which can effectively improve the pressure relief efficiency.

[0091] Further, in some embodiments, the area of ​​the first through hole 210 is S1, the area of ​​the adhesive layer 300 is S2, and the area of ​​the expansion member 400 is S3, where 0.1 ≤ (S2 + S3): S1 ≤ 10. (S2 + S3): S1 can be equal to 0.1, 0.5, 1, 2, 5, or 10. Specifically, if the ratio of the sum of the areas of the adhesive layer 300 and the expansion member 400 to the area of ​​the first through hole 210 is less than 0.1, then there are two possibilities: one is that the area of ​​the first through hole 210 is too small, which will lead to a decrease in pressure relief efficiency; the other is that the sum of the areas of the adhesive layer 300 and the expansion member 400 is too large, which may lead to waste of materials in the adhesive layer 300 and the expansion member 400, and because the area of ​​the adhesive layer 300 is too large, the adhesive force is too large, which will lead to a slower pressure relief efficiency. If the ratio of the sum of the areas of the adhesive layer 300 and the expansion member 400 to the area of ​​the first through hole 210 is greater than 10, then there are two possibilities: either the area of ​​the first through hole 210 is too small, which would lead to reduced pressure relief efficiency; or the sum of the areas of the adhesive layer 300 and the expansion member 400 is too large, which could result in waste of materials for both the adhesive layer 300 and the expansion member 400, and also, due to the excessively large area of ​​the adhesive layer 300, excessive adhesive force, which would lead to slower pressure relief efficiency. See Table 1 below for details.

[0092] Table 1

[0093] As can be seen from Table 1, when comparing Examples 1 to 6 with Comparative Examples 1 to 2, when S1, S2, and S3 do not satisfy 0.1≤(S2+S3):S1≤10, the area of ​​the first through hole 210 is too small. This situation will lead to a decrease in pressure relief efficiency. Another situation is that the sum of the area of ​​the adhesive layer 300 and the area of ​​the expansion member 400 is too large. This may lead to waste of materials of the adhesive layer 300 and the expansion member 400. Also, because the area of ​​the adhesive layer 300 is too large, the adhesive force is too large, which will lead to a slower pressure relief efficiency, and vice versa.

[0094] Further, in some embodiments, the area of ​​the adhesive layer 300 is S2, the area of ​​the expansion member 400 is S3, and 0.1 ≤ S2 : S3 ≤ 10. Specifically, S2 : S3 can be equal to 0.1, 0.5, 1, 2, 5, or 10. Specifically, if the ratio of the area of ​​the adhesive layer 300 to the area of ​​the expansion member 400 is less than 0.1, then there are two possibilities: either the area of ​​the adhesive layer 300 is too small, or the surface area of ​​the expansion member 400 is too large. Both of these possibilities will lead to poor bonding. If the ratio of the area of ​​the adhesive layer 300 to the area of ​​the expansion member 400 is greater than 10, then there are two possibilities: either the area of ​​the adhesive layer 300 is too large, or the surface area of ​​the expansion member 400 is too small. Both of these possibilities will lead to insufficient expansion force of the expansion member 400, slow pressure relief efficiency, and high bonding strength.

[0095] Furthermore, in some embodiments, the expansion temperature of the expansion element 400 is T1, and the melting point of the adhesive layer 300 is T2, where T2-T1 ≥ 5℃. Specifically, the temperature difference between the expansion temperature of the expansion element 400 and the melting point of the adhesive layer 300 can be 5℃, 6℃, 8℃, or 10℃. That is, when the internal temperature of the casing 200 is high and the cell experiences thermal runaway, the high temperature will first cause the expansion element 400 to expand, and then cause the adhesive layer 300 to melt. The expansion element 400 expands first, providing a pushing force to both the casing 200 and the sealing element 100, thereby pushing the sealing element 100 away from the casing 200. Then, the adhesive layer 300 begins to melt, reducing the adhesion between the sealing element 100 and the casing 200. The expansion element 400 can then more easily separate the casing 200 and the sealing element 100, thereby achieving rapid pressure relief of the battery. See Table 2 below for details.

[0096] Table 2

[0097] As shown in Table 2, comparing Examples 1 to 3 with Comparative Example 1, when T1 and T2 satisfy T2-T1≥5℃, the internal temperature of the casing 200 is high. During thermal runaway of the battery cell, the high temperature first causes the expansion member 400 to expand, followed by the melting of the adhesive layer 300. The expansion member 400 expands first, exerting a pushing force on both the casing 200 and the sealing member 100, thus pushing the sealing member 100 away from the casing 200. Then, the adhesive layer 300 begins to melt, reducing the adhesion between the sealing member 100 and the casing 200. The expansion member 400 can then more easily separate the casing 200 and the sealing member 100, thereby allowing the battery to release pressure as quickly as possible. However, since the expansion member 400 has not yet expanded when the adhesive layer 300 melts, the pressure release is slower.

[0098] Furthermore, in some embodiments, the expansion temperature of the expansion element 400 is T1, where 95℃≤T1≤110℃. The expansion temperature of the expansion element 400 can be 95℃, 98℃, 100℃, or 110℃. When the expansion temperature of the expansion element 400 is less than 95℃, the expansion element 400 expands prematurely before the cell reaches thermal runaway. The expansion element 400 will act on the casing 200 and the sealing element 100, affecting the adhesion of the adhesive layer 300 and resulting in lower battery sealing reliability. When the expansion temperature of the expansion element 400 is greater than 110℃, the expansion element 400 has not yet played its role when the adhesive layer 300 melts. This reduces the pressure relief rate and pressure relief sensitivity, preventing the battery from depressurizing quickly.

[0099] Furthermore, in some embodiments, the melting point of the adhesive layer 300 is T2, where 100℃≤T2≤130℃. The melting point of the adhesive layer 300 can be 100℃, 110℃, 120℃, or 130℃. When the melting point of the adhesive layer 300 is less than 100℃, the adhesive layer 300 may melt before the cell reaches thermal runaway, which will result in low sealing reliability of the battery. When the melting point of the adhesive layer 300 is greater than 130℃, the melting point of the adhesive layer 300 is too high, and the adhesive layer 300 is difficult to melt when the cell experiences thermal runaway, making it impossible to quickly separate the casing 200 and the sealing component 100, and thus depressurize the battery.

[0100] Further, referring to Figures 1 to 4, in some embodiments, the housing 200 includes a metal part 220 and a main body 230. The main body 230 is provided with a storage cavity and a first through hole 210. The metal part 220 is provided with a fourth through hole 221, which communicates with the first through hole 210. One side of the metal part 220 is welded to the main body 230, and the other side of the metal part 220 is connected to the adhesive layer 300. Along the thickness direction of the metal part 220, the projected area of ​​the metal part 220 is D1, and the projected area of ​​the sealing member 100 is D2, where D1 > D2. Specifically, to improve the manufacturing efficiency of the battery, the metal part 220, the adhesive layer 300, the expansion member 400, and the sealing member 100 can be assembled together, and then the metal part 220 can be welded to the main body 230. In other words, during battery manufacturing, the adhesive layer 300 can be placed between the metal part 220 and the sealing part 100, and then hot-pressed to bond the expansion part 400 and the metal part 220 together. Next, the expansion part 400 is placed between the metal part 220 and the expansion part 400, and finally, the metal part 220 is welded to the main body 230. However, when D1 < D2, this will result in the sealing part 100 having an excessively large area, affecting the welding of the metal part 220 and the main body 230. See Table 3 below for details.

[0101] Table 3

[0102] As can be seen from Table 3, the area of ​​the sealing component 100 is too large, which affects the welding of the metal component 220 and the main body 230, making the structure impossible to achieve and resulting in low reliability.

[0103] Further, referring to Figure 5, in some embodiments, the battery further includes a terminal post 500, which is electrically connected to the battery cell. The terminal post 500 is insulated from the housing 200, and the sum of the thicknesses of the metal part 220, the adhesive layer 300, and the sealing member 100 is less than the length of the terminal post 500. That is, the battery cell is disposed in the storage cavity, the terminal post 500 is insulated from the housing, and the terminal post 500 is electrically connected to the battery cell. The sealing member 100 and the terminal post are located on the same side of the housing 200. The height of the terminal post 500 protruding relative to the housing 200 is L1, and the height of the sealing member 100 protruding relative to the housing 200 (the height of the sealing member 100 protruding relative to the housing 200 is the sum of the thicknesses of the metal part 220, the adhesive layer 300, and the sealing member 100) is L2, where L2 ≤ L1. Specifically, if the sum of the thicknesses of the metal part 220, the adhesive layer 300, and the sealing member 100 is greater than the length of the terminal post, the energy density of the battery may be reduced. Furthermore, if the combined thickness of the metal part 220, the adhesive layer 300, and the sealing part 100 is too large, the sealing part 100 may come into contact with the casing during the battery's hot box test, thereby conducting heat. This could cause the adhesive layer 300 to melt, reducing its bonding performance and affecting the battery's sealing performance.

[0104] Furthermore, in some embodiments, the electrical device includes the battery of any of the above embodiments. Specifically, the adhesive layer 300 is disposed between the sealing member 100 and the housing 200. The adhesive layer 300 can fix the sealing member 100 to the housing 200, thereby achieving the sealing member 100 sealing the first through hole 210. When the internal pressure of the battery increases, since the expansion member 400 is located between the housing 200 and the sealing member 100, and the expansion force of the expansion member 400 is greater than the adhesive force of the adhesive layer 300 when heated, the expansion member 400 can, under heating conditions, disconnect the connection between the sealing member 100 and the housing 200 through its own expansion force, thereby allowing the internal pressure of the housing 200 to be released quickly. Specifically, the battery can effectively and quickly release pressure. Furthermore, the electrical device with this battery has higher safety.

[0105] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention. Furthermore, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other.

Claims

1. Battery, including: Sealing components; The housing has a storage cavity and a first through hole, the storage cavity and the first through hole being in communication; An adhesive layer is disposed between the sealing member and the housing, with both sides of the adhesive layer bonded to the sealing member and the housing respectively, and the sealing member sealing the first through hole; An expansion member is disposed between the sealing member and the housing, with its two sides connected to the sealing member and the housing respectively. The expansion member is configured such that when the expansion member expands due to heat, the expansion force of the expansion member is greater than the adhesive force of the adhesive layer.

2. The battery of claim 1, wherein, The adhesive layer is provided with a second through hole, and the first through hole and the second through hole are connected.

3. The battery of claim 1, wherein, The expansion member is provided with a third through hole, and the adhesive layer is disposed in the third through hole.

4. The battery of claim 1, wherein, The adhesive layer includes a first adhesive layer and a second adhesive layer. The side of the first adhesive layer opposite to the second adhesive layer is bonded to the housing, and the side of the second adhesive layer opposite to the first adhesive layer is bonded to the sealing member. The melting point of the first adhesive layer is lower than that of the second adhesive layer.

5. The battery of claim 1, wherein, The area of ​​the first through hole is S1, the area of ​​the adhesive layer is S2, and the area of ​​the expansion member is S3, where 0.1 ≤ (S2 + S3) : S1 ≤ 10.

6. The battery of claim 1, wherein, The area of ​​the adhesive layer is S2, and the area of ​​the expansion member is S3, where 0.1 ≤ S2 : S3 ≤ 10.

7. The battery of claim 1, wherein, The expansion temperature of the expansion component is T1, the melting point of the adhesive layer is T2, and T2-T1≥5℃.

8. The battery of claim 7, wherein, The expansion temperature of the expansion component is T1, where 95℃≤T1≤110℃.

9. The battery of claim 7, wherein, The melting point of the adhesive layer is T2, where 100℃≤T2≤130℃.

10. The battery of claim 1, wherein, The housing includes a metal component and a main body. The main body is provided with the storage cavity and the first through hole. The metal component is provided with a fourth through hole, which communicates with the first through hole. One side of the metal component is welded to the main body, and the other side of the metal component is connected to the adhesive layer. Along the thickness direction of the metal component, the projected area of ​​the metal component is D1, and the projected area of ​​the sealing component is D2, where D1 > D2.

11. The battery of claim 1, wherein, The battery also includes terminals and cells. The cells are disposed in the storage cavity. The terminals are insulated from the housing and electrically connected to the cells. The sealing member and the terminals are located on the same side of the housing. The height of the terminals protruding from the housing is L1, and the height of the sealing member protruding from the housing is L2, where L2 ≤ L1.

12. Electrical equipment, including the battery as claimed in any one of claims 1 to 11.

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