Battery and electric equipment

Abstract

The utility model discloses a battery and electric equipment, the battery includes: a housing having a storage cavity and a pressure relief hole, the pressure relief hole being communicated with the storage cavity; the battery cell is arranged in the storage cavity; the plugging piece comprises a first metal layer and a second metal layer, the first metal layer is attached to the second metal layer, and the expansion coefficients of the first metal layer and the second metal layer are different; the two ends of the adhesive layer are bonded to the shell and the second metal layer respectively, and the adhesive layer can be fused when the battery cell reaches a threshold value, so that the pressure in the storage cavity is relieved through the pressure relief hole. The battery provided by the utility model can have relatively high pressure relief efficiency.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery and electrical equipment. Background Technology

[0002] In related technologies, a battery includes a casing and battery cells, with the cells housed inside the casing. To improve battery safety, an explosion-proof valve can be installed on the casing. This valve releases pressure in the event of thermal runaway, preventing the battery from exploding. Specifically, the casing has a pressure relief hole, which is sealed with an adhesive metal sheet. When the battery experiences thermal runaway, the internal pressure and temperature of the casing rise, causing the adhesive to melt. This allows high-temperature, high-pressure gas to break through the metal sheet seal and release pressure. However, because the adhesive melts slowly, the pressure relief efficiency is relatively slow. Utility Model Content

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a battery that has a faster pressure relief efficiency.

[0004] This utility model also proposes an electrical device.

[0005] The battery according to a first aspect embodiment of the present invention includes:

[0006] The housing has a storage cavity and a pressure relief hole, the pressure relief hole and the storage cavity being in communication;

[0007] The battery cell is disposed in the storage cavity;

[0008] The sealing component includes a first metal layer and a second metal layer, wherein the first metal layer is attached to the second metal layer, and the first metal layer and the second metal layer have different coefficients of thermal expansion.

[0009] An adhesive layer is attached to the housing and the second metal layer at both ends. The adhesive layer can melt when the cell reaches a threshold, so that the pressure in the storage cavity can be released through the pressure relief hole.

[0010] The battery according to the present invention has at least the following beneficial effects: the two ends of the adhesive layer are respectively bonded to the shell and the second metal layer. In this way, the sealing component can be bonded to the shell through the adhesive layer. When the cell experiences thermal runaway, the temperature of the cell rises and reaches a threshold, which causes the adhesive layer to begin to melt. In addition, since the first metal layer and the second metal layer are bonded together, and the expansion coefficients of the first metal layer and the second metal layer are different, the first metal layer and the second metal layer will expand after being heated. After the first metal layer and the second metal layer expand and deform due to heat, the contact area between the second metal layer and the adhesive layer will decrease, weakening the adhesion between the second metal layer and the adhesive layer. Specifically, the high temperature and high pressure gas inside the storage cavity can easily disconnect the sealing component from the shell, so that the high pressure and high temperature gas can be released from the pressure relief hole. In the prior art, the release of high temperature and high pressure gas requires waiting for the adhesive layer to melt, so the pressure relief efficiency is slow. However, in this application, after the first metal layer and the second metal layer expand, the adhesive layer bonding effect will be poor, improving the efficiency of separation between the sealing component and the shell, thereby further improving the pressure relief efficiency. Specifically, the battery has a relatively fast pressure relief efficiency.

[0011] According to some embodiments of the present invention, the coefficient of expansion of the first metal layer in the battery is greater than that of the second metal layer.

[0012] According to some embodiments of the present invention, the thickness of the first metal layer is L1, the thickness of the second metal layer is L2, and L1-L2≥0.01mm.

[0013] According to some embodiments of the present invention, the coefficient of expansion of the first metal layer in the battery is smaller than that of the second metal layer.

[0014] According to some embodiments of the present invention, the thickness of the first metal layer is L1, the thickness of the second metal layer is L2, and L2-L1≥0.01mm.

[0015] According to some embodiments of the present invention, the battery casing includes a main body and a metal part, the metal part being provided with a through hole, the main body being provided with the storage cavity and the pressure relief hole, the metal part being welded to the main body, and the pressure relief hole and the through hole being connected.

[0016] According to some embodiments of the present invention, the dimension of the sealing member protruding relative to the housing is A, where A ≤ 0.55 mm.

[0017] According to some embodiments of the present invention, the thickness of the metal part in the battery is B, where 0.02mm≤B≤0.1mm.

[0018] According to some embodiments of the present invention, the difference between the expansion coefficient of the first metal layer and the expansion coefficient of the second metal layer is C, where C ≥ 5 (1E-6 / K).

[0019] The electrical device according to the second aspect of the present invention includes the battery described in any one of the first aspect embodiments.

[0020] The electrical device according to the present invention has at least the following beneficial effects: the two ends of the adhesive layer are respectively bonded to the shell and the second metal layer. In this way, the sealing component can be bonded to the shell through the adhesive layer. When the battery cell experiences thermal runaway, the temperature of the battery cell rises and reaches a threshold temperature, which causes the adhesive layer to begin to melt. In addition, since the first metal layer and the second metal layer are bonded together, and the expansion coefficients of the first metal layer and the second metal layer are different, the first metal layer and the second metal layer will expand after being heated. After the first metal layer and the second metal layer expand and deform due to heat, the contact area between the second metal layer and the adhesive layer will decrease, weakening the adhesion between the second metal layer and the adhesive layer. Specifically, the high temperature and high pressure gas inside the storage cavity can easily disconnect the sealing component from the shell, so that the high pressure and high temperature gas can be released from the pressure relief hole. In the prior art, the release of high temperature and high pressure gas requires waiting for the adhesive layer to melt, so the pressure relief efficiency is slow. However, in this application, after the first metal layer and the second metal layer expand, the adhesive layer bonding effect will be poor, improving the efficiency of separation between the sealing component and the shell, thereby further improving the pressure relief efficiency. Specifically, the battery has a relatively fast pressure relief efficiency. Furthermore, electrical devices equipped with this battery have better safety features.

[0021] Additional aspects and advantages of this 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

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0023] Figure 1 This is a schematic diagram of a battery according to the first embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of a battery according to the second embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of a battery according to the third embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram of the battery according to the fourth embodiment of the present invention.

[0027] Figure label:

[0028] 100 housing, 110 metal parts, 111 through holes, 120 main body, 130 storage cavity, 140 pressure relief hole, 200 sealing parts, 210 first metal layer, 220 second metal layer, and 300 adhesive layer. Detailed Implementation

[0029] The embodiments of this utility model 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 this utility model, and should not be construed as limiting this utility model.

[0030] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model 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 limitations on this utility model.

[0031] In the description of this utility model, "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.

[0032] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0033] In the description of this utility model, 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 this utility model. 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.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] 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.

[0038] 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.).

[0039] 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 / 3 O2 (also known as NCM333), LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM523), LiNi0.5 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.

[0040] 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.

[0041] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0042] 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.).

[0043] 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.

[0044] 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.

[0045] 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.

[0046] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0047] In some implementations, the battery cell also includes an isolation element disposed between the positive and negative terminals.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] Among them, the gel electrolyte includes a polymer as the electrolyte backbone network, combined with an ionic liquid - lithium salt.

[0055] Solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0056] 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.

[0057] 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.

[0058] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0059] In some implementations, the battery cell has a wound structure. The positive and negative electrode plates are wound into a wound structure.

[0060] In some implementations, the battery cell has a laminated structure.

[0061] As an example, multiple positive and negative electrodes can be set, and multiple positive and multiple negative electrodes can be stacked alternately.

[0062] 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.

[0063] As an example, both the positive and negative electrode plates are folded to form multiple stacked folded segments.

[0064] As an example, multiple separators can be provided, each positioned between any adjacent positive or negative electrode plates.

[0065] As an example, the separators can be continuously arranged, either by folding or rolling between any adjacent positive or negative electrode plates.

[0066] In some implementations, the battery cell can be cylindrical, flat, or polygonal, etc.

[0067] 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.

[0068] 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.

[0069] 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.

[0070] 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.

[0071] 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.

[0072] 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.

[0073] 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.

[0074] 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.

[0075] In related technologies, a battery includes a casing and a cell, with the cell housed inside the casing. To improve battery safety, an explosion-proof valve can be installed on the casing. This valve releases pressure in the event of thermal runaway, preventing the battery from exploding. Specifically, the casing has a pressure relief hole, which is sealed with an adhesive metal sheet. When the battery experiences thermal runaway, the internal pressure and temperature of the casing rise, causing the adhesive to melt. This allows high-temperature, high-pressure gas to break through the metal sheet seal and release pressure. However, because the adhesive melts slowly, the pressure relief efficiency is relatively slow. Therefore, this application proposes a battery.

[0076] Please refer to Figures 1 to 4In some embodiments, the battery includes: a housing 100, a battery cell, a sealing member 200, and an adhesive layer 300. The housing 100 has a storage cavity 130 and a pressure relief hole 140, which communicates with the storage cavity 130. The shape of the housing 100 is not specifically limited; it can be a cuboid or a cube. The pressure relief hole 140 is disposed on the side wall of the housing 100, and its shape can be circular or square. The battery cell is disposed in the storage cavity 130. The battery cell can be formed by stacking electrode sheets, or by winding electrode sheets after stacking them. The sealing member 200 includes a first metal layer 210 and a second metal layer 220. The first metal layer 210 is attached to the second metal layer 220. The first metal layer 210 is attached to the second metal layer 220 by welding the first metal layer 210 and the second metal layer 220. The first metal layer 210 and the second metal layer 220 have different coefficients of thermal expansion. For example, the first metal layer 210 can be made of aluminum, manganese, or magnesium, and the second metal layer 220 can be made of chromium, germanium, molybdenum, or tin. The adhesive layer 300 can be a hot melt adhesive. The two ends of the adhesive layer 300 are respectively bonded to the housing 100 and the second metal layer 220. The adhesive layer 300 can melt when the cell reaches a threshold, so that the pressure in the storage cavity 130 can be released through the pressure relief hole 140. Specifically, the two ends of the adhesive layer 300 are respectively bonded to the housing 100 and the second metal layer 220. Thus, the sealing component 200 can be bonded to the housing 100 via the adhesive layer 300. When the battery cell experiences thermal runaway, the temperature of the battery cell rises, reaching a threshold temperature, which causes the adhesive layer 300 to begin melting. Furthermore, because the first metal layer 210 and the second metal layer 220 are bonded together, and their coefficients of thermal expansion are different, the first metal layer 210 and the second metal layer 220 will expand upon heating. This thermal expansion and deformation of the first metal layer 210 and the second metal layer 220 will cause the second metal layer 220 to... The reduced contact area between the first metal layer 210 and the adhesive layer 300 weakens the adhesion between the second metal layer 220 and the adhesive layer 300. Specifically, the high-temperature and high-pressure gas inside the storage cavity 130 can easily disconnect the sealing element 200 from the housing 100, allowing the high-pressure and high-temperature gas to escape from the pressure relief hole 140. In the prior art, the high-temperature and high-pressure gas needs to wait for the adhesive layer 300 to melt before it can escape, resulting in a slow pressure relief efficiency. In this application, the expansion of the first metal layer 210 and the second metal layer 220 leads to a poor adhesion of the adhesive layer 300, improving the efficiency of separation between the sealing element 200 and the housing 100, thereby further improving the pressure relief efficiency. In essence, the battery can achieve a faster pressure relief efficiency.

[0077] The aforementioned ability of the adhesive layer 300 to melt when the cell reaches its threshold specifically refers to the fact that the adhesive layer 300 can be made of hot melt adhesive, which melts at higher temperatures. The cell's threshold refers to the temperature at which thermal runaway occurs, such as 95°C, 100°C, or 110°C. Specifically, after the first metal layer 210 and the second metal layer 220 are bonded together, when the temperature rises, the first metal layer 210 and the second metal layer 220 can bulge away from the pressure relief hole 140, or they can bulge closer to the pressure relief hole 140. That is, the central area of ​​the sealing component 200 can be concave or convex, which reduces the contact area between the edge of the sealing component 200 and the adhesive layer 300, weakening the adhesive effect of the adhesive layer 300, thus allowing the battery to separate the sealing component 200 from the casing 100 with less pressure. For details, please refer to... Figure 2 and Figure 3 , Figure 2 and Figure 3 The diagram illustrates the deformation of the sealing component 200 after expansion.

[0078] Furthermore, the following describes a specific way in which the expansion coefficients of the first metal layer 210 and the second metal layer 220 are different. In some embodiments, the expansion coefficient of the first metal layer 210 is greater than that of the second metal layer 220. Specifically, the material of the first metal layer 210 can be one of antimony, copper, manganese, nickel, aluminum, iron, and magnesium, and the material of the second metal layer 220 can be one of chromium, germanium, iridium, molybdenum, platinum, or tin.

[0079] Further, in some embodiments, the thickness of the first metal layer 210 is L1, the thickness of the second metal layer 220 is L2, and L1-L2≥0.01mm. Specifically, the coefficient of thermal expansion of the first metal layer 210 is greater than that of the second metal layer 220, the thickness difference between the first metal layer 210 and the second metal layer 220 can be 0.01mm, 0.02mm, or 0.03mm, the deformation of the first metal layer 210 is greater than that of the second metal layer 220, and the centers of the first metal layer 210 and the second metal layer 220 can both bulge in a direction away from the pressure relief hole 140.

[0080] Furthermore, the following describes another specific way in which the expansion coefficients of the first metal layer 210 and the second metal layer 220 are different. In some embodiments, the expansion coefficient of the first metal layer 210 is smaller than that of the second metal layer 220. Specifically, the material of the first metal layer 210 can be one of chromium, germanium, iridium, molybdenum, platinum, or tin, and the material of the second metal layer 220 can be one of antimony, copper, manganese, nickel, aluminum, iron, and magnesium.

[0081] Further, in some embodiments, the thickness of the first metal layer 210 is L1, the thickness of the second metal layer 220 is L2, and L2-L1≥0.01mm. Specifically, the coefficient of thermal expansion of the first metal layer 210 is less than that of the second metal layer 220, the thickness difference between the first metal layer 210 and the second metal layer 220 can be 0.01mm, 0.02mm, or 0.03mm, the deformation of the first metal layer 210 is less than that of the second metal layer 220, and the centers of the first metal layer 210 and the second metal layer 220 can both bulge towards the pressure relief hole 140.

[0082] Further, please refer to Figure 4 The specific structure of the housing 100 is described below. In some embodiments, the housing 100 includes a main body 120 and a metal part 110. The metal part 110 is provided with a through hole 111, and the main body 120 is provided with a storage cavity 130 and a pressure relief hole 140. The metal part 110 is welded to the main body 120, and the pressure relief hole 140 and the through hole 111 are connected. In some cases, during battery manufacturing, the sealing member 200 can be bonded to the metal part 110 first, and then the metal part 110 can be welded to the main body 120. The metal part 110 can be made of stainless steel, and the main body 120 can also be made of stainless steel. The diameter of the sealing member 200 is smaller than the diameter of the metal part 110. The diameter of the pressure relief hole 140 can be between 1 mm and 5 mm. The diameter of the metal part 110 can be between 2 mm and 10 mm.

[0083] Further, in some embodiments, the protrusion of the sealing member 200 relative to the housing 100 is A, where A ≤ 0.55 mm. Specifically, the protrusion of the sealing member 200 relative to the housing 100 is equal to the sum of the thickness of the sealing member 200, the thickness of the adhesive layer 300, and the thickness of the metal member 110. Alternatively, the protrusion of the sealing member 200 relative to the housing 100 is equal to the sum of the thickness of the sealing member 200 and the thickness of the adhesive layer 300. The specific value of A can be 0.1 mm, 0.2 mm, 0.4 mm, 0.5 mm, or 0.55 mm. When the value of A is greater than 0.55 mm, the protrusion of the sealing member 200 relative to the housing 100 is large, which leads to a lower energy density of the battery. The thicknesses of the adhesive layer 300 and the metal member 110 can be between 0.02 mm and 0.1 mm.

[0084] Furthermore, in some embodiments, the thickness of the metal part 110 is B, where 0.02 mm ≤ B ≤ 0.1 mm. Specifically, the thickness of the metal part 110 can be 0.02 mm, 0.05 mm, 0.08 mm, or 0.1 mm. When the thickness of the metal part 110 is less than 0.02 mm, the metal part 110 is too thin, which results in poor welding performance to the main body 120. When the thickness of the metal part 110 is greater than 0.1 mm, the metal part 110 is too thick, which ultimately results in a larger protrusion of the sealing member 200 from the housing 100, thereby reducing the energy density of the battery.

[0085] Furthermore, in some embodiments, the difference between the coefficient of thermal expansion of the first metal layer 210 and the coefficient of thermal expansion of the second metal layer 220 is C, where C ≥ 5 (1E-6 / K). Specifically, the difference between the coefficient of thermal expansion of the first metal layer 210 and the coefficient of thermal expansion of the second metal layer 220 can be 5 (1E-6 / K), 6 (1E-6 / K), 7 (1E-6 / K), 8 (1E-6 / K), or 9 (1E-6 / K). When the difference between the coefficient of thermal expansion of the first metal layer 210 and the coefficient of thermal expansion of the second metal layer 220 is less than 5 (1E-6 / K), the expansion degree of the first metal layer 210 and the second metal layer 220 is too small, resulting in insufficient strength to weaken the adhesive effect of the adhesive tape and reduce the pressure relief efficiency.

[0086] In some embodiments, the electrical device includes a battery according to any of the above embodiments. Specifically, the two ends of the adhesive layer 300 are respectively bonded to the housing 100 and the second metal layer 220. In this way, the sealing member 200 can be bonded to the housing 100 through the adhesive layer 300. When the battery cell experiences thermal runaway, the temperature of the battery cell rises and reaches a threshold temperature, which causes the adhesive layer 300 to begin to melt. In addition, since the first metal layer 210 and the second metal layer 220 are bonded together, and the coefficients of thermal expansion of the first metal layer 210 and the second metal layer 220 are different, the first metal layer 210 and the second metal layer 220 will expand after being heated. After the first metal layer 210 and the second metal layer 220 expand and deform due to heat, this will cause the second metal layer 220 to... The reduced contact area between the first metal layer 210 and the adhesive layer 300 weakens the adhesion between the second metal layer 220 and the adhesive layer 300. Specifically, the high-temperature and high-pressure gas inside the storage cavity 130 can easily disconnect the sealing element 200 from the housing 100, allowing the high-pressure and high-temperature gas to escape through the pressure relief hole 140. In the prior art, the high-temperature and high-pressure gas needs to wait for the adhesive layer 300 to melt before escaping, resulting in a slow pressure relief efficiency. In this application, the expansion of the first metal layer 210 and the second metal layer 220 leads to poor adhesion of the adhesive layer 300, improving the efficiency of separation between the sealing element 200 and the housing 100, thereby further improving the pressure relief efficiency. Specifically, the battery can have a faster pressure relief efficiency. Furthermore, electrical devices equipped with this battery have better safety.

[0087] 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, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. A battery, characterized by, The battery comprises: a shell having a storage cavity and a pressure relief hole, the pressure relief hole and the storage cavity being in communication; an electric core arranged in the storage cavity; a blocking member comprising a first metal layer and a second metal layer, the first metal layer being attached to the second metal layer, the first metal layer and the second metal layer having different expansion coefficients; a glue layer, two ends of the glue layer being respectively bonded to the shell and the second metal layer, the glue layer being capable of melting when the electric core reaches a threshold value, so that the pressure in the storage cavity is relieved through the pressure relief hole.

2. The battery of claim 1, wherein, The expansion coefficient of the first metal layer is greater than the expansion coefficient of the second metal layer.

3. The battery of claim 2, wherein, The thickness of the first metal layer is L1, and the thickness of the second metal layer is L2, L1-L2≥0.01mm.

4. The battery of claim 1, wherein, The expansion coefficient of the first metal layer is less than the expansion coefficient of the second metal layer.

5. The battery of claim 4, wherein, The thickness of the first metal layer is L1, and the thickness of the second metal layer is L2, L2-L1≥0.01mm.

6. The battery of claim 1, wherein, The shell comprises a main body and a metal piece, the metal piece being provided with a through hole, the main body being provided with the storage cavity and the pressure relief hole, the metal piece being welded to the main body, the pressure relief hole and the through hole being in communication.

7. The battery of claim 6, wherein, The size of the blocking member protruding relative to the shell is A, A≤0.55mm.

8. The battery of claim 6, wherein, The thickness of the metal piece is B, 0.02mm≤B≤0.1mm.

9. The battery of claim 1, wherein, The difference between the expansion coefficient of the first metal layer and the expansion coefficient of the second metal layer is C, C≥5(1E-6 / K).

10. An electrical device, characterized by The battery comprises any one of claims 1 to 9.

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