Battery and electric equipment

Abstract

The invention discloses a battery and an electric device. The battery comprises a plugging member; the shell is provided with a storage cavity and a first through hole, and the storage cavity is communicated with the first through hole; the glue layer is arranged between the plugging piece and the shell, the two sides of the glue layer are bonded to the plugging piece and the shell respectively, and the plugging piece seals the first through hole; the expansion piece is arranged between the plugging piece and the shell, the two sides of the expansion piece are connected to the plugging piece and the shell respectively, and the expansion piece is configured in the mode that when the expansion piece is heated to expand, the expansion force of the expansion piece is larger than the bonding force of the adhesive layer. The battery provided by the invention can effectively and quickly release pressure.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a battery and an electrical device. Background Art

[0002] In the related art, when the battery encounters internal short circuit, overcharge, over discharge, external impact or high temperature, a large amount of heat and gas may be generated inside the battery, which may cause an explosion. In order to effectively avoid the problem of battery explosion, an explosion-proof valve can be set. Specifically, when the pressure inside the battery is too high, the explosion-proof valve can discharge the gas inside the battery, thereby effectively avoiding battery explosion.

[0003] Furthermore, the specific method of pressure relief of the existing battery is that a pressure relief hole is provided on the shell, and the metal part is bonded to the shell to seal the pressure relief hole. When the pressure inside the battery is too high, the temperature inside the battery is high, which will cause the adhesive to fail, so that the pressure relief hole is opened to relieve pressure. However, the adhesive still has a high adhesion when it melts, which will cause the metal part to still block the pressure relief hole, and the gas inside the battery cannot be discharged as soon as possible. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a battery that can effectively and quickly release pressure.

[0005] The invention also provides an electrical device.

[0006] A battery according to a first aspect of the present invention comprises:

[0007] Blocking parts;

[0008] A housing is provided with a storage cavity and a first through hole, wherein the storage cavity is in communication with the first through hole;

[0009] An adhesive layer is provided between the blocking member and the shell, two sides of the adhesive layer are respectively bonded to the blocking member and the shell, and the blocking member closes the first through hole;

[0010] An expansion member is arranged between the blocking member and the shell, and two sides of the expansion member are respectively connected to the blocking member and the shell. 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.

[0011] The battery according to the embodiment of the present invention has at least the following beneficial effects: the glue layer is arranged between the plugging member and the shell, and the glue layer can fix the plugging member on the shell, so that the plugging member closes the first through hole, wherein, when the pressure inside the battery increases, since the expansion member is located between the shell and the plugging member, and when the expansion member expands due to heat, the expansion force of the expansion member is greater than the adhesive force of the glue layer, therefore, the expansion member can disconnect the connection between the plugging member and the shell by its own expansion force under heat, so that the pressure inside the shell can be discharged as soon as possible. Specifically, the battery can effectively and quickly release pressure.

[0012] In the battery according to some embodiments of the present invention, the glue layer is provided with a second through hole, and the first through hole is connected to the second through hole.

[0013] In the battery according to some embodiments of the present invention, the expansion member is provided with a third through hole, and the glue layer is provided in the third through hole.

[0014] In a battery according to some embodiments of the present invention, the glue layer includes a first glue layer and a second glue layer, the first glue layer is bonded to the shell on a side facing away from the second glue layer, the second glue layer is bonded to the sealing member on a side facing away from the first glue layer, and the melting point of the first glue layer is lower than the melting point of the second glue layer.

[0015] In the battery according to some embodiments of the present invention, the area of ​​the first through hole is S1, the area of ​​the glue layer is S2, the area of ​​the expansion piece is S3, and 0.1≤(S2+S3): S1≤10.

[0016] In the battery according to some embodiments of the present invention, the area of ​​the glue layer is S2, the area of ​​the expansion piece is S3, and 0.1≤S2:S3≤10.

[0017] In the battery according to some embodiments of the present invention, the expansion temperature of the expansion member is T1, the melting point of the glue layer is T2, and T2-T1≥5°C.

[0018] In batteries according to some embodiments of the present invention, the expansion temperature of the expansion member is T1, 95°C≤T1≤110°C.

[0019] In batteries according to some embodiments of the present invention, the melting point of the glue layer is T2, 100°C≤T2≤130°C.

[0020] According to some embodiments of the battery of the present invention, the shell includes a metal part and a main body, the main body is provided with the storage cavity and the first through hole, the metal part is provided with a fourth through hole, the fourth through hole is connected to the first through hole, one side of the metal part is welded to the main body, and the other side of the metal part is connected to the glue layer, and along the thickness direction of the metal part, the projected area of ​​the metal part is D1, and the projected area of ​​the sealing part is D2, and D1>D2.

[0021] According to some embodiments of the present invention, the battery further comprises a pole and a battery cell, the battery cell is arranged in the storage cavity, the pole is insulated and connected to the shell, and the pole and the battery cell are electrically connected, the blocking member and the pole are located on the same side of the shell, the height of the pole protruding relative to the shell is L1, the height of the blocking member protruding relative to the shell is L2, and L2≤L1.

[0022] An electrical device according to an embodiment of the second aspect of the present invention comprises a battery according to any one of the embodiments of the first aspect.

[0023] The electrical equipment according to the embodiment of the present invention has at least the following beneficial effects: the glue layer is arranged between the sealing member and the shell, and the glue layer can fix the sealing member on the shell, so that the sealing member closes the first through hole, wherein, when the pressure inside the battery increases, since the expansion member is located between the shell and the sealing member, and when the expansion member expands due to heat, the expansion force of the expansion member is greater than the adhesion force of the glue layer, therefore, the expansion member can disconnect the sealing member and the shell through its own expansion force when heated, so that the pressure inside the shell can be discharged as soon as possible. Specifically, the battery can effectively and quickly release pressure. Furthermore, the electrical equipment with the battery is safer.

[0024] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0026] Figure 1 is a partial schematic diagram of a battery according to a first embodiment of the present invention;

[0027] Figure 2 A partial explosion diagram of a battery according to some embodiments of the present invention;

[0028] Figure 3 is a partial schematic diagram of a battery according to a second embodiment of the present invention;

[0029] Figure 4is a partial schematic diagram of a battery according to a third embodiment of the present invention;

[0030] Figure 5 Schematic diagram of a battery according to some embodiments of the present invention.

[0031] Reference numerals:

[0032] The blocking member 100 , the shell 200 , the first through hole 210 , the metal member 220 , the fourth through hole 221 , the main body 230 , the adhesive layer 300 , the second through hole 310 , the expansion member 400 , the third through hole 410 , and the pole 500 . DETAILED DESCRIPTION

[0033] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0034] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0035] In the description of the present invention, "several" means more than one, "many" means more than two, "greater than", "less than", "exceed", etc. are understood to exclude the number itself, and "above", "below", "within", etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0036] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0037] In the description of the present invention, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0038] The battery can be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel hydrogen battery, a nickel cadmium battery, a lead storage battery, etc., which is not limited in the embodiments of the present application.

[0039] A battery generally includes a cell. The cell includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of the battery, active ions (such as lithium ions) are inserted and removed back and forth between the positive electrode and the negative electrode. The separator is arranged between the positive electrode and the negative electrode to prevent the positive and negative electrodes from short-circuiting, while allowing active ions to pass through.

[0040] In some embodiments, the positive electrode may be a positive electrode sheet, and the positive electrode sheet 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.

[0041] As an example, the positive electrode current collector has two surfaces facing each other in its thickness direction, and the positive electrode active material is disposed on either or both of the two facing surfaces of the positive electrode current collector.

[0042] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, 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. may be used. The composite current collector may include a polymer material base and a metal layer. The composite current collector may 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.).

[0043] As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides and their respective modified compounds. However, the present application is not limited to these materials, and other traditional materials that can be used as positive electrode active materials for batteries can also be used. These positive electrode active materials can be used alone or in combination of two or more. Among them, examples of lithium-containing phosphates may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon. Examples of lithium transition metal oxides 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, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also referred to as NCM333), LiNi 0.5 Co 0.2 Mn 0.3 O2 (also referred to as NCM523), LiNi 0.5 Co 0.25 Mn 0.25 O2 (also referred to as NCM211), LiNi 0.6 Co 0.2 Mn 0.2 O2 (also referred to as NCM622), LiNi 0.8 Co 0.1 Mn 0.1 O2 (also referred to as NCM811), lithium nickel cobalt aluminum oxide (such as LiNi 0.85 Co 0.15 Al 0.05 O2)) and at least one of its modified compounds, etc.

[0044] In some embodiments, the positive electrode may be a foamed metal. The foamed metal may be a nickel foam, a copper foam, an aluminum foam, an alloy foam, etc. When the foamed metal is used as the positive electrode, the positive electrode active material may not be provided on the surface of the foamed metal, but of course, the positive electrode active material may also be provided. As an example, a lithium source material, potassium metal or sodium metal may also be filled or / and deposited in the foamed metal, and the lithium source material is lithium metal and / or a lithium-rich material.

[0045] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0046] As an example, the negative electrode current collector may be a metal foil, a foamed metal or a composite current collector. For example, as the metal foil, aluminum or stainless steel treated with silver, stainless steel, copper, aluminum, nickel, carbon electrode, nickel or titanium, etc. may be used. The foamed metal may be a nickel foam, a copper foam, an aluminum foam, an alloy foam, etc. The composite current collector may include a polymer material base and a metal layer. The composite current collector may 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.).

[0047] 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.

[0048] As an example, the negative electrode current collector has two surfaces facing each other in its thickness direction, and the negative electrode active material is disposed on either or both of the two facing surfaces of the negative electrode current collector.

[0049] As an example, the negative electrode active material may adopt the negative electrode active material for the battery known in the art. 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. The silicon-based material may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites and silicon alloys. The tin-based material may be selected from at least one of elemental tin, tin oxide compounds and tin alloys. However, the present application is not limited to these materials, and other traditional 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.

[0050] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0051] In some embodiments, the battery cell further includes a separator, which is disposed between the positive electrode and the negative electrode.

[0052] In some embodiments, the separator is a separator membrane. There may be many types of separator membranes, and any known porous separator membrane with good chemical stability and mechanical stability may be selected.

[0053] As an example, the material of the separator may include at least one of glass fiber, non-woven 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 may be attached to the surface of the positive and negative electrodes.

[0054] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transmit ions and isolate the positive and negative electrodes.

[0055] In some embodiments, the battery further comprises an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The electrolyte may be liquid, gel or solid. The liquid electrolyte comprises an electrolyte salt and a solvent.

[0056] In some embodiments, the electrolyte salt may include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bisfluorosulfonyl imide, lithium bistrifluoromethanesulfonyl imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalatoborate, lithium dioxalatoborate, lithium difluorodioxalatophosphate, and lithium tetrafluorooxalatophosphate.

[0057] In some embodiments, the solvent may include at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, cyclopentane, dimethyl sulfone, methyl ethyl sulfone and diethyl sulfone. The solvent may also be an ether solvent. The ether solvent may include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyltetrahydrofuran, diphenyl ether and crown ether.

[0058] Among them, the gel electrolyte includes a skeleton network with a polymer as the electrolyte, combined with an ionic liquid-lithium salt.

[0059] Among them, solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0060] As an example, the polymer solid electrolyte may be polyether (polyethylene oxide), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, a single ion polymer, polyionic liquid-lithium salt, cellulose, and the like.

[0061] As an example, the inorganic solid electrolyte may include an oxide solid electrolyte (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON film), a sulfide solid electrolyte (crystalline lithium superion conductor (lithium germanium phosphosulfide, silver germanium sulfide), amorphous sulfide) and one or more of a halide solid electrolyte, a nitride solid electrolyte and a hydride solid electrolyte.

[0062] As an example, the composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0063] In some embodiments, the battery cell is a wound structure, wherein the positive electrode sheet and the negative electrode sheet are wound into a wound structure.

[0064] In some embodiments, the battery cell has a stacked structure.

[0065] As an example, a plurality of positive electrode sheets and a plurality of negative electrode sheets may be provided respectively, and the plurality of positive electrode sheets and the plurality of negative electrode sheets may be alternately stacked.

[0066] As an example, a plurality of positive electrode sheets may be provided, and the negative electrode sheet may be folded to form a plurality of stacked folded segments, with a positive electrode sheet being sandwiched between adjacent folded segments.

[0067] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of folded sections that are stacked.

[0068] As an example, a plurality of separators may be provided, each of which is provided between any adjacent positive electrode sheets or negative electrode sheets.

[0069] As an example, the separator may be disposed continuously, and may be disposed between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0070] In some embodiments, the shape of the battery cell can be cylindrical, flat, or polygonal.

[0071] In some embodiments, the battery cell is provided with a tab, which can lead current out of the battery cell. The tab includes a positive tab and a negative tab.

[0072] In some embodiments, the battery may include a housing. The housing is used to encapsulate components such as the battery cell and the electrolyte. The housing may be a steel housing, an aluminum housing, a plastic housing (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing), or an aluminum-plastic film.

[0073] As an example, the battery may be a cylindrical battery, a prismatic battery, a soft-pack battery or a battery of other shapes. Prismatic batteries include but are not limited to square-shell batteries, blade-shaped batteries, and polygonal batteries. Polygonal batteries may be, for example, hexagonal batteries.

[0074] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more batteries to provide higher voltage and capacity.

[0075] In some embodiments, the battery may be a battery module. When there are multiple batteries, the multiple batteries are arranged and fixed to form a battery module.

[0076] In some embodiments, the battery may be a battery pack, which includes a case and batteries, wherein the batteries or battery modules are accommodated in the case.

[0077] In some embodiments, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0078] The embodiment of the present application provides an electric device using a battery as a power source, and the electric device may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, etc. Among them, the electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0079] In the related art, when the battery encounters internal short circuit, overcharge, over discharge, external impact or high temperature, a large amount of heat and gas may be generated inside the battery, which may cause an explosion. In order to effectively avoid the problem of battery explosion, an explosion-proof valve can be set. Specifically, when the pressure inside the battery is too high, the explosion-proof valve can discharge the gas inside the battery, thereby effectively avoiding battery explosion.

[0080] Furthermore, the specific method of pressure relief of the existing battery is that a pressure relief hole is provided on the shell, and the metal part is bonded to the shell to close the pressure relief hole. When the pressure inside the battery is too high, the temperature inside the battery is high, which will cause the adhesive to fail, so that the pressure relief hole is opened to relieve pressure. However, the adhesive still has a high adhesion when it melts, which will cause the metal part to still block the pressure relief hole, and the gas inside the battery cannot be discharged as soon as possible. To this end, the present application proposes a battery.

[0081] Please refer to Figures 1 to 3In some embodiments, the battery includes: a battery cell, a plugging member 100, a shell 200, a glue layer 300 and an expansion member 400. The shell 200 is provided with a storage cavity and a first through hole 210, and the storage cavity and the first through hole 210 are connected. The shape of the shell 200 can be rectangular, square, cylindrical or triangular, etc., and the shape of the shell 200 is not specifically limited. The shell 200 can be connected to the negative electrode of the battery cell, so as to be charged. Among them, in addition to being used for pressure relief, the first through hole 210 can also be used to inject electrolyte into the storage cavity. The glue layer 300 is arranged between the plugging member 100 and the shell 200, and the two sides of the glue layer 300 are respectively bonded to the plugging member 100 and the shell 200, and the plugging member 100 closes the first through hole 210. That is, through the bonding of the glue layer 300, the plugging member 100 can seal the first through hole 210. In addition, when the internal pressure of the battery is too high and the heat is high, the glue layer 300 melts due to the heat, and the viscosity decreases. The sealing member 100 cannot block the first through hole 210, which can cause the gas in the storage cavity to leak out.

[0082] The expansion member 400 is disposed between the plugging member 100 and the shell 200, and the two sides of the expansion member 400 are respectively connected to the plugging member 100 and the shell 200, and the expansion member 400 is configured such that when the expansion member 400 expands due to heat, the expansion force of the expansion member 400 is greater than the adhesive force of the adhesive layer 300. Specifically, the adhesive layer 300 is disposed between the plugging member 100 and the shell 200, and the adhesive layer 300 can fix the plugging member 100 on the shell 200, so that the plugging member 100 closes the first through hole 210, wherein, when the pressure inside the battery increases, since the expansion member 400 is located between the shell 200 and the plugging member 100, and when the expansion member 400 expands due to heat, the expansion force of the expansion member 400 is greater than the adhesive force of the adhesive layer 300, therefore, the expansion member 400 can disconnect the connection between the plugging member 100 and the shell 200 by its own expansion force under heat, so that the pressure inside the shell 200 can be discharged as soon as possible. Specifically, batteries can effectively and quickly release pressure.

[0083] It is further explained that, in the present application, the sealing member 100 and the housing 200 are connected by the adhesive layer 300, so that the pressure relief effect can be achieved. However, since the adhesive layer 300 is still sticky when it is heated and melted, it will also cause adhesion between the sealing member 100 and the housing 200, and the first through hole 210 cannot be fully opened immediately to allow gas to escape. After the expansion member 400 is further provided, the expansion force of the expansion member 400 after being heated is greater than the adhesive force, and the expansion member 400 will accelerate the opening of the first through hole 210, thereby achieving pressure relief as soon as possible.

[0084] Among them, the material of the expansion member 400 can be a heat-expandable microsphere foaming agent, which is a tiny spherical particle that can expand in volume within a specific temperature range. It is usually composed of a thermoplastic polymer shell and a low-boiling hydrocarbon compound encapsulated inside. This unique structure allows the microspheres to expand when heated. The heat-expandable microsphere foaming agent may include polyvinyl alcohol (PVA) microspheres, polystyrene (PS) microspheres, polyacrylate (PA) microspheres, etc.

[0085] The material of the adhesive layer 300 can be hot melt adhesive, which can be quickly plasticized and solidified after heating, making it very suitable for occasions that require rapid assembly. In the battery manufacturing process, the use of hot melt adhesive can greatly shorten the production cycle and improve production efficiency.

[0086] Furthermore, the shapes of the first through hole 210, the adhesive layer 300 and the blocking member 100 are not specifically limited. For example, the shapes of the first through hole 210, the adhesive layer 300 and the blocking member 100 can be rectangular, square, circular, oblong or irregular polygonal.

[0087] Furthermore, there are many situations in which the adhesive layer 300 is disposed between the housing 200 and the blocking member 100. For example, the adhesive layer 300 can cover the first through hole 210, and then the two sides of the adhesive layer 300 are respectively bonded to the housing 200 and the blocking member 100; or, the adhesive layer 300 is provided with a second through hole 310, the second through hole 310 is connected to the first through hole 210, and the adhesive layer 300 is distributed at the edge of the first through hole 210. For details, please refer 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 shell 200 and the blocking member 100. Specifically, when the temperature inside the shell 200 increases, the temperature of the shell 200 will rise, and then the shell 200 will conduct to the side of the adhesive layer 300 facing away from the blocking member 100, and the bonding between the shell 200 and the adhesive layer 300 will weaken. The high-temperature gas will also enter the second through hole 310 through the first through hole 210, so that the blocking member 100 is heated, and the bonding between the blocking member 100 and the adhesive layer 300 will weaken. In this way, the blocking member 100 can be quickly separated from the shell 200 to achieve rapid pressure relief of the battery.

[0088] For further information, please refer to Figures 1 to 3In some embodiments, the expansion member 400 is provided with a third through hole 410, and the glue layer 300 is provided in the third through hole 410. When manufacturing the battery, the manufacturing process may be to place the solidified glue layer 300 between the plugging member 100 and the shell 200, and then heat press the plugging member 100 and the shell 200 to melt the glue layer 300. After the glue layer 300 melts, the plugging member 100 and the shell 200 can be bonded. After that, the expansion member 400 is placed in the gap between the shell 200 and the plugging member 100, and the expansion member 400 is surrounded by the edge of the glue layer 300. In this way, it is convenient to manufacture the battery and effectively improve the battery manufacturing efficiency. If the expansion member 400 is first placed between the shell 200 and the plugging member 100 during the manufacturing process of the battery, then when the glue layer 300 is hot-pressed, the expansion member 400 may be heated and expanded, thereby failing to improve the manufacturing yield of the battery.

[0089] Further, in some embodiments, the adhesive layer 300 includes a first adhesive layer 300 and a second adhesive layer 300, the first adhesive layer 300 is bonded to the shell 200 on one side facing away from the second adhesive layer 300, the second adhesive layer 300 is bonded to the sealing member 100 on one side facing away from the first adhesive layer 300, and the melting point of the first adhesive layer 300 is lower than the melting point of the second adhesive layer 300. Specifically, the melting point of the first adhesive layer 300 is lower than that of the second adhesive layer 300. When the temperature inside the shell 200 is high, the first adhesive layer 300 first melts quickly after being heated, and the bonding force between the first adhesive layer 300 and the shell 200 is reduced; while the melting point of the second adhesive layer 300 is greater than that of the first adhesive layer 300. The second adhesive layer 300 can continue to adhere to the sealing member 100 after being heated. In this way, when the battery is out of control, the adhesive layer 300 can adhere to the sealing member 100 and fall off from the shell 200 together with the sealing member 100, which can effectively improve the pressure relief efficiency.

[0090] 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 piece 400 is S3, 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 area of ​​the adhesive layer 300 and the area of ​​the expansion piece 400 to the area of ​​the first through hole 210 is less than 0.1, then there are two situations. One situation is that the area of ​​the first through hole 210 is too small, which will lead to a decrease in the pressure relief efficiency. The other situation is that the sum of the area of ​​the adhesive layer 300 and the area of ​​the expansion piece 400 is too large, which may lead to a waste of materials of the adhesive layer 300 and the expansion piece 400, and because the adhesive layer 300 area is too large and the bonding force is too large, it will lead to a slow pressure relief efficiency. If the ratio of the sum of the area of ​​the adhesive layer 300 and the area of ​​the expansion piece 400 to the area of ​​the first through hole 210 is greater than 10, there are two situations: one is that the area of ​​the first through hole 210 is too small, which will lead to reduced pressure relief efficiency; the other is that the sum of the area of ​​the adhesive layer 300 and the area of ​​the expansion piece 400 is too large, which may lead to waste of materials of the adhesive layer 300 and the expansion piece 400, and because the area of ​​the adhesive layer 300 is too large, the adhesive force is too large, which will lead to slower pressure relief efficiency. For details, please refer to Table 1 below.

[0091] Table 1

[0092] S1 S2 S3 (S2+S3): S1 Pressure relief efficiency Example 1 4.5 7.78 1.54 2 normal Example 2 4.5 0.8 8 2 normal Example 3 4.5 8.5 0.85 2 normal Example 4 12.5 0.625 0.625 0.1 normal Example 5 2.25 5.68 5.68 5.05 normal Example 6 1.26 6.3 6.3 10 normal Comparative Example 1 1.13 6.9 5.8 11 Slow Comparative Example 2 12.8 0.383 0.65 0.08 Slow

[0093] It can be seen from Table 1 that by 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, which will lead to a decrease in the pressure relief efficiency. Another situation is that the sum of the area of ​​the adhesive layer 300 and the area of ​​the expansion piece 400 is too large, which may lead to a waste of materials of the adhesive layer 300 and the expansion piece 400, and because the area of ​​the adhesive layer 300 is too large and the bonding force is too large, the pressure relief efficiency is slower, otherwise it is faster.

[0094] Further, in some embodiments, the area of ​​the adhesive layer 300 is S2, the area of ​​the expansion piece 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 piece 400 is less than 0.1, then there are two situations, one is that the area of ​​the adhesive layer 300 is too small, and the other is that the surface of the expansion piece 400 is too large, both of which will result in poor bonding effect. If the ratio of the area of ​​the adhesive layer 300 to the area of ​​the expansion piece 400 is greater than 10, then there are two situations, one is that the area of ​​the adhesive layer 300 is too large, and the other is that the surface of the expansion piece 400 is too small, both of which will result in insufficient expansion force of the expansion piece 400, slow pressure relief efficiency, and high bonding strength.

[0095] Further, in some embodiments, the expansion temperature of the expansion piece 400 is T1, the melting point of the glue layer 300 is T2, and T2-T1≥5°C. Specifically, the temperature difference between the expansion temperature of the expansion piece 400 and the melting point of the glue layer 300 can be 5°C, 6°C, 8°C or 10°C. That is, when the temperature inside the shell 200 is high and the battery cell is thermally runaway, the high temperature will first cause the expansion piece 400 to expand, and then cause the glue layer 300 to melt. The expansion piece 400 expands first, and the expansion piece 400 will give a thrust to the shell 200 and the plugging piece 100 respectively, thereby pushing the plugging piece 100 away from the shell 200, and then the glue layer 300 begins to melt, and the bonding force between the plugging piece 100 and the shell 200 is reduced, and the expansion piece 400 can more easily separate the shell 200 and the plugging piece 100, thereby achieving battery pressure relief as soon as possible. For details, please refer to Table 2 below.

[0096] Table 2

[0097] T1 T2 T2-T1 Pressure relief efficiency Example 1 95 100 5 normal Example 2 102.5 115 12.5 Faster Example 3 110 130 20 Faster Comparative Example 1 110 100 -10 Slow

[0098] It can be seen from Table 2 that, by comparing Examples 1 to 3 with Comparative Example 1, when T1 and T2 satisfy T2-T1≥5°C, the temperature inside the shell 200 is relatively high. When the battery cell is in thermal runaway, the high temperature will first cause the expansion piece 400 to expand, and then cause the glue layer 300 to melt. The expansion piece 400 expands first, and the expansion piece 400 will give a thrust to the shell 200 and the plugging piece 100 respectively, thereby pushing the plugging piece 100 away from the shell 200. Then the glue layer 300 begins to melt, and the bonding force between the plugging piece 100 and the shell 200 is reduced. The expansion piece 400 can more easily separate the shell 200 and the plugging piece 100, thereby achieving the battery pressure relief as soon as possible. When the glue layer 300 melts, the expansion piece 400 has not yet expanded, which will result in slower pressure relief.

[0099] Further, in some embodiments, the expansion temperature of the expansion member 400 is T1, 95°C≤T1≤110°C. The expansion temperature of the expansion member 400 may be 95°C, 98°C, 100°C or 110°C. When the expansion temperature of the expansion member 400 is less than 95°C, the expansion member 400 expands in advance before the battery cell reaches thermal runaway, and the expansion member 400 acts on the housing 200 and the sealing member 100, affecting the adhesion of the adhesive layer 300, resulting in a low sealing reliability of the battery. When the expansion temperature of the expansion member 400 is greater than 110°C, when the adhesive layer 300 melts, the expansion member 400 has not yet taken effect, which will reduce the pressure relief speed and reduce the pressure relief sensitivity, and the battery cannot be depressurized as quickly as possible.

[0100] Further, in some embodiments, the melting point of the glue layer 300 is T2, 100°C≤T2≤130°C. The melting point of the glue layer 300 may be 100°C, 110°C, 120°C or 130°C. When the melting point of the glue layer 300 is less than 100°C, the glue layer 300 may melt before the battery cell reaches thermal runaway, which will result in low sealing reliability of the battery; when the melting point of the glue layer 300 is greater than 130°C, the melting point of the glue layer 300 is too high, and the glue layer 300 is difficult to melt when the battery cell reaches thermal runaway, and the housing 200 and the sealing member 100 cannot be separated as soon as possible, and the battery is depressurized.

[0101] For further information, please refer 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, the fourth through hole 221 is connected to 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 glue layer 300. Along the thickness direction of the metal part 220, the projection area of ​​the metal part 220 is D1, and the projection area of ​​the blocking member 100 is D2, and D1>D2. Specifically, in order to improve the manufacturing efficiency of the battery, the metal part 220, the glue layer 300, the expansion member 400 and the blocking member 100 can be assembled, and then the metal part 220 can be welded to the main body 230. That is, when manufacturing the battery, the glue layer 300 can be placed between the metal part 220 and the plugging part 100, and then hot-pressed to make the glue layer 300 bond the expansion part 400 and the metal part 220, and then the expansion part 400 is set between the metal part 220 and the expansion part 400, and finally the metal part 220 is welded to the main body 230. When D1 < D2, this will cause the area of ​​the plugging part 100 to be too large, affecting the welding of the metal part 220 and the main body 230. For details, please refer to Table 3 below.

[0102] Table 3

[0103] D1 D2 Structural reliability Example 1 3.2 2.1 reliable Comparative Example 1 2 3 Unreliable

[0104] It can be seen from Table 3 that the area of ​​the blocking member 100 is too large, which affects the welding of the metal member 220 and the main body 230, and the structure cannot be realized, and the reliability is low.

[0105] For further information, please refer to Figure 5 In some embodiments, the battery further comprises a pole 500, the pole 500 is electrically connected to the battery cell, the pole 500 is insulated and connected to the shell 200, and the sum of the thickness of the metal part 220, the glue layer 300 and the plugging member 100 is less than the length of the pole 500. That is, the battery cell is arranged in the storage cavity, the pole 500 is insulated and connected to the shell, and the pole 500 is electrically connected to the battery cell, and the plugging member 100 and the pole are located on the same side of the shell 200. The height of the pole 500 protruding relative to the shell 200 is L1, and the height of the plugging member 100 protruding relative to the shell 200 (the protrusion of the plugging member 100 relative to the shell 200 is the sum of the thickness of the metal part 220, the glue layer 300 and the plugging member 100) is L2, and L2≤L1. Specifically, if the sum of the thickness of the metal part 220, the glue layer 300 and the plugging member 100 is greater than the length of the pole, the energy density of the battery may be reduced. In addition, if the sum of the thicknesses of the metal part 220, the adhesive layer 300 and the sealing part 100 is too large, during the hot box test of the battery, the sealing part 100 may come into contact with the box body, thereby conducting heat, which will cause the adhesive layer 300 to melt, reduce the bonding performance, and affect the sealing performance of the battery.

[0106] Further, in some embodiments, the electrical device includes a battery of any one of the above embodiments. Specifically, the glue layer 300 is arranged between the plugging member 100 and the shell 200, and the glue layer 300 can fix the plugging member 100 on the shell 200, so that the plugging member 100 closes the first through hole 210, wherein, when the pressure inside the battery increases, since the expansion member 400 is located between the shell 200 and the plugging member 100, and when the expansion member 400 expands due to heat, the expansion force of the expansion member 400 is greater than the adhesive force of the glue layer 300, therefore, the expansion member 400 can disconnect the connection between the plugging member 100 and the shell 200 by its own expansion force under heat, so that the pressure inside the shell 200 can be discharged as soon as possible. Specifically, the battery can effectively and quickly release pressure. Further, the electrical device having the battery is safer.

[0107] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Various changes can be made within the knowledge of ordinary technicians in the relevant technical field without departing from the purpose of the present invention. In addition, the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

Claims

1. A battery, characterized in that include: Blocking parts; A housing is 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 is provided between the blocking member and the shell, two sides of the adhesive layer are respectively bonded to the blocking member and the shell, and the blocking member closes the first through hole; An expansion member is arranged between the blocking member and the shell, and two sides of the expansion member are respectively connected to the blocking member and the shell. 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 according to claim 1, characterized in that The adhesive layer is provided with a second through hole, and the first through hole is communicated with the second through hole.

3. The battery according to claim 1, characterized in that The expansion member is provided with a third through hole, and the adhesive layer is arranged in the third through hole.

4. The battery according to claim 1, characterized in that The adhesive layer includes a first adhesive layer and a second adhesive layer. The first adhesive layer is bonded to the shell on one side facing away from the second adhesive layer. The second adhesive layer is bonded to the sealing member on one side facing away from the first adhesive layer. The melting point of the first adhesive layer is lower than that of the second adhesive layer.

5. The battery according to claim 1, characterized in that The area of ​​the first through hole is S1, the area of ​​the adhesive layer is S2, the area of ​​the expansion piece is S3, 0.1≤(S2+S3): S1≤10.

6. The battery according to claim 1, characterized in that The area of ​​the adhesive layer is S2, the area of ​​the expansion piece is S3, 0.1≤S2:S3≤10.

7. The battery according to claim 1, characterized in that The expansion temperature of the expansion member is T1, the melting point of the adhesive layer is T2, and T2-T1≥5°C.

8. The battery according to claim 7, characterized in that The expansion temperature of the expansion member is T1, 95°C≤T1≤110°C.

9. The battery according to claim 7, characterized in that The melting point of the adhesive layer is T2, 100°C≤T2≤130°C.

10. The battery according to claim 1, characterized in that The shell includes a metal part and a main body, the main body is provided with the storage cavity and the first through hole, the metal part is provided with a fourth through hole, the fourth through hole is connected to the first through hole, one side of the metal part is welded to the main body, and the other side of the metal part is connected to the adhesive layer, along the thickness direction of the metal part, the projection area of ​​the metal part is D1, and the projection area of ​​the blocking part is D2, D1>D2.

11. The battery according to claim 1, characterized in that The battery also includes a pole and a battery cell, the battery cell is arranged in the storage cavity, the pole is insulated and connected to the shell, and the pole and the battery cell are electrically connected, the blocking member and the pole are located on the same side of the shell, the pole protrudes from the shell by a height L1, and the blocking member protrudes from the shell by a height L2, L2≤L1.

12. Electrical equipment, characterized in that: Comprising the battery as claimed in any one of claims 1 to 11.

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