Battery monomer, battery device and electric device

Abstract

The embodiment of the utility model provides a battery monomer, a battery device and a power utilization device, the battery monomer comprises a shell, a pressure relief mechanism and a mesh plate, and the shell comprises a first wall; the electrode assembly is arranged in the shell; the pressure relief mechanism is arranged on the first wall; the mesh plate can be arranged between the electrode assembly and the pressure relief mechanism in an insulating mode and is provided with a plurality of meshes in a dense mode. According to the invention, the fire risk during thermal runaway of the single battery can be reduced.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery cell, a battery device, and an electrical device. Background Art

[0002] Energy conservation and emission reduction are key to the sustainable development of the automotive industry. Electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of the industry's sustainable development. For electric vehicles, battery devices are a crucial factor in their development.

[0003] A battery device is usually composed of multiple battery cells. When thermal runaway occurs in a battery cell, reducing the risk of fire is an issue that needs to be studied. Utility Model Content

[0004] The present application provides a battery cell, a battery device, and an electrical device to reduce the risk of fire of the battery cell during thermal runaway.

[0005] In a first aspect, an embodiment of the present application provides a battery cell, comprising: a shell including a first wall; an electrode assembly disposed in the shell; a pressure relief mechanism disposed on the first wall; and a mesh plate that can be insulated and disposed between the electrode assembly and the pressure relief mechanism and is densely provided with a plurality of meshes.

[0006] The present application sets a mesh plate between the electrode assembly and the pressure relief mechanism. When thermal runaway occurs in the battery cell, the gas inside the battery cell passes smoothly through the mesh holes on the mesh plate and is ejected through the pressure relief mechanism. At the same time, the high-temperature solid matter inside the battery cell is blocked by the mesh plate and cannot pass through the mesh holes on the mesh plate, thereby achieving the purpose of separating the high-temperature solid matter from the gas and solving the problem of high-temperature solid matter igniting combustible gas and causing fire.

[0007] In some embodiments, the mesh plate is an insulating plate, or the mesh plate includes a base and an insulating layer covering the base.

[0008] Therefore, the mesh plate can ensure insulation during normal operation of the battery cell.

[0009] In some embodiments, along the thickness direction of the first wall, the projection of the mesh plate on the first wall completely covers the pressure relief mechanism.

[0010] In the event of thermal runaway of a battery cell, the gas ejected from the pressure relief mechanism passes through the mesh plate, effectively blocking the solid matter inside the battery cell from being ejected from the pressure relief mechanism, achieving solid-gas separation and reducing the risk of fire caused by the ejection of high-temperature solid matter inside the battery cell igniting combustible gas.

[0011] In some embodiments, the first wall is provided with a liquid injection hole; along the thickness direction of the first wall, the projection of the mesh plate on the first wall completely covers the liquid injection hole.

[0012] The projection of the mesh plate on the first wall completely covers the injection hole along the thickness direction of the first wall. During the injection process, the electrolyte flows into the outer shell through the mesh holes on the mesh plate, so that the electrode assembly is more fully soaked, and the impact force of the liquid on the electrode assembly is reduced, thereby reducing the risk of damage to the electrode assembly and improving the reliability of the battery cell.

[0013] In some embodiments, the electrode assembly includes an electrode body and a tab, and the tab is arranged on the first end surface of the electrode body; the battery cell also includes a adapter and an electrode terminal, and the electrode terminal is arranged on the first wall, and the adapter connects the tab and the electrode terminal; along the thickness direction of the first wall, the mesh plate is located between the adapter and the first end surface.

[0014] The mesh plate is located between the adapter and the first end face. When the tab is bent, for example, when the end cover is pressed onto the open end of the shell to bend the tab, or when the tabs of multiple electrode assemblies are connected through the adapter and then docked to form the tab, the mesh plate can prevent the root of the tab from being inserted into the first end face of the electrode body, thereby reducing the risk of short circuit.

[0015] In some embodiments, the tabs include a positive tab and a negative tab, and the positive tab and the negative tab are spaced apart along a first direction, and the first direction is perpendicular to the thickness direction of the first wall; along the first direction, the size of the mesh plate is greater than the spacing distance between the positive tab and the negative tab.

[0016] By making the size of the mesh plate larger than the spacing between the positive electrode tab and the negative electrode tab, the area ratio of the mesh plate to the first end face can be increased. In the event of thermal runaway of the battery cell, more solid matter can be blocked, reducing the risk of solid matter escape, and further reducing the risk of fire caused by the ejection of high-temperature solid matter inside the battery cell igniting combustible gas.

[0017] In some embodiments, the mesh plate is provided with a first notch and a second notch, the positive electrode tab is located in the first notch, and the negative electrode tab is located in the second notch.

[0018] By cooperating with the positive electrode tab and the negative electrode tab respectively through the first notch and the second notch, the displacement of the mesh plate can be limited. When the tab is bent, the mesh plate can more reliably block the root of the tab from being inserted into the first end face of the electrode body, further reducing the risk of short circuit.

[0019] In some embodiments, the mesh plate is connected to the first end surface via an adhesive.

[0020] The mesh plate is connected to the first end face by an adhesive, which can improve the installation firmness of the mesh plate and further reduce the risk of mesh plate displacement.

[0021] In some embodiments, the ratio of the sum of the areas of all meshes on the mesh plate to the area of ​​the mesh plate is greater than or equal to 0.2.

[0022] Therefore, the larger mesh area ratio can make the mesh plate exhaust smoother.

[0023] In some embodiments, the area of ​​a single mesh on the mesh plate is less than or equal to 1 cm 2 .

[0024] Reasonable single mesh size is conducive to the effective interception of solid particles.

[0025] In some embodiments, the mesh plate has a thickness of 0.05 mm to 10 mm.

[0026] When the thickness of the mesh plate is 0.05mm~10mm, it can not only have good impact resistance, but also reduce space occupancy, which is beneficial to improving the battery volume energy density.

[0027] In some embodiments, the mesh plate has a thickness of 0.06 mm to 3 mm.

[0028] When the thickness of the mesh plate is 0.06mm~3mm, it can not only further have good impact resistance, but also further reduce space occupancy, which is conducive to improving the battery volume energy density.

[0029] In some embodiments, the insulating plate has a melting point greater than or equal to 200°C.

[0030] As a result, the high temperature resistance of the insulation board is improved, and the ejection of solid matter can be effectively prevented.

[0031] In some embodiments, the insulating plate is made of polyimide, polyetheretherketone, polyphenylene sulfide, ceramic, epoxy resin, glass fiber, glass fiber reinforced composite, or alumina fiber reinforced mullite.

[0032] The insulation board is made of high temperature resistant material, which not only plays an insulating role, but also can effectively prevent the ejection of solid matter.

[0033] In some embodiments, the melting point of the substrate is greater than or equal to 600°C.

[0034] The base in the mesh plate has a high melting point, which can improve the high temperature resistance of the insulation board and effectively prevent the ejection of solid matter.

[0035] In some embodiments, the substrate is made of copper, tungsten, titanium, iron, nickel, or cobalt; and the insulating layer is made of PE, PP, PET, aluminum oxide, silicon dioxide, or zirconium oxide.

[0036] In the event of thermal runaway of a battery cell, such as when a large-scale short circuit has occurred inside the battery cell, the base inside the mesh plate can still provide perfect support to ensure the interception of solid matter.

[0037] In a second aspect, an embodiment of the present application provides a battery device comprising a battery cell as described in any of the above embodiments.

[0038] In a third aspect, an embodiment of the present application provides an electrical device, comprising the battery cell described in any of the above embodiments, or the battery device described above.

[0039] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0041] Figure 1 A schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0042] Figure 2 An exploded view of a battery device provided in some embodiments of the present application;

[0043] Figure 3 An exploded view of a battery cell provided in some embodiments of the present application;

[0044] Figure 4 A schematic diagram of the structure of a mesh plate provided in some embodiments of the present application;

[0045] Figure 5 A schematic structural diagram of a mesh plate provided in some other embodiments of the present application;

[0046] Figure 6 A cross-sectional view of a mesh plate provided for some embodiments of the present application;

[0047] Figure 7 A cross-sectional view of a battery cell provided for some embodiments of the present application;

[0048] Figure 8 for Figure 7 A partial enlarged schematic diagram of a battery cell;

[0049] Figure 9 for Figure 7 Cross-section view at the AA position.

[0050] icon:

[0051] 1000-vehicle; 100-battery device; 200-controller; 300-motor; 10-housing; 11-first sub-housing; 12-second sub-housing; 20-battery cell; 21-housing; 211-shell; 212-end cover; 213-first wall; 22-electrode assembly; 22a-first end face; 221-electrode body; 222-tab; 2221-positive tab; 2222-negative tab; 23-pressure relief mechanism; 24-mesh plate; 241-first notch; 242-second notch; 243-base; 244-insulating layer; 25-liquid injection hole; 26-adapter; 27-electrode terminal; 28-adhesive. DETAILED DESCRIPTION

[0052] The following detailed description of the embodiments of the present application is provided in conjunction with the accompanying drawings and examples. The following detailed description of the embodiments and the accompanying drawings are used to illustrate the principles of the present application, but are not intended to limit the scope of the present application, that is, the present application is not limited to the described embodiments.

[0053] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field to which this application belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions.

[0054] The terms "first", "second", etc. in the specification of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0055] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0056] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0057] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0058] The term "multiple" used in this application refers to more than two (including two). Similarly, "multiple groups" refers to more than two (including two) groups, and "multiple sheets" refers to more than two (including two) sheets.

[0059] The following detailed description of the embodiments of the present application is provided in conjunction with the accompanying drawings and examples. The following detailed description of the embodiments and the accompanying drawings are used to illustrate the principles of the present application, but are not intended to limit the scope of the present application, that is, the present application is not limited to the described embodiments.

[0060] The terms "first", "second", etc. in the specification of this application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0061] The battery device mentioned in the embodiments of the present application may include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly may include multiple battery cells, which are connected in series, parallel, or hybrid via a busbar.

[0062] In some embodiments, a battery cell assembly may be formed by arranging multiple battery cells. For example, the battery cell assembly may be a battery module, which is formed by arranging and fixing multiple battery cells to form a single module. For example, a battery module may be formed by bundling multiple battery cells with cable ties.

[0063] In some embodiments, the battery device may be a battery pack, which includes a case and one or more battery cell assemblies, wherein the battery cell assemblies are housed in the case.

[0064] As an example, the battery cell assembly may be a battery module, and the battery cell assembly may be accommodated in the box by fixing the battery module in the box.

[0065] As an example, the battery cell assembly may also be housed in the box by directly fixing a plurality of battery cells to the box.

[0066] As an example, the housing may include a first sub-housing and a second sub-housing. The first and second sub-housings snap together to form an enclosed space within the housing to house the battery cell assembly. Enclosed here means covered or closed, and can be either sealed or unsealed. The first sub-housing may be a top cover or a bottom plate.

[0067] As an example, the box may include a top cover, a frame, and a bottom plate, wherein the top cover and the bottom plate are respectively connected to the frame to form a closed space inside the box to accommodate the battery cell assembly.

[0068] As an example, the box body can be used as a part of the chassis structure of the vehicle. For example, the top cover of the box body can become at least a part of the floor of the vehicle, or the frame of the box body can become at least a part of the crossbeam and longitudinal beam of the vehicle.

[0069] In some embodiments, the battery device refers to an energy storage device, which includes a box with a door on at least one side. The energy storage device includes an energy storage container, an energy storage cabinet, etc.

[0070] In the embodiment of the present application, the battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0071] The battery cells may be, but are not limited to, lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-hydrogen batteries, nickel-cadmium batteries, lead-acid batteries, and the like.

[0072] A battery cell includes an electrode assembly. This assembly consists of a positive electrode, a negative electrode, and a separator. During the charge and discharge process, active ions (such as lithium ions) move back and forth between the positive and negative electrodes. The separator, placed between the positive and negative electrodes, prevents short circuits while allowing the active ions to pass through.

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

[0074] In some embodiments, the housing includes an end cap assembly and a shell. The shell has an opening. The end cap assembly includes an end cap and an electrode terminal disposed on the end cap. The end cap seals the opening to form a sealed space for accommodating the electrode assembly, electrolyte, and other substances. The shell may have one or more openings. One or more end caps may also be provided.

[0075] In some embodiments, the housing is provided with at least one electrode terminal, which is electrically connected to a tab of the electrode assembly. The electrode terminal may be directly connected to the tab or indirectly connected to the tab via an adapter. The electrode terminal may be provided on an end cap or on the housing.

[0076] In some embodiments, the electrode terminal may include a post and a conductive member, and the post may electrically connect the conductive member and the electrode assembly.

[0077] In some embodiments, the housing is provided with an explosion-proof valve, which is used to release the internal pressure of the battery cell. The explosion-proof valve can be provided on the end cap or on the housing.

[0078] In some embodiments, the housing can be a sealed structure or a non-sealed structure. For example, when the housing is a sealed structure, the housing can protect the electrode assembly and prevent leakage of electrolyte. When the housing is a non-sealed structure, the housing can also protect the electrode assembly. A sealing bag can be included between the housing and the electrode assembly to encapsulate the electrode assembly and electrolyte. Specifically, the sealing bag can be a bag-shaped insulating member or an aluminum-plastic film.

[0079] As an example, the battery cells may be cylindrical, prismatic, soft-pack or other shaped battery cells. Prismatic battery cells include square-shell, blade-shaped, and polygonal batteries. Polygonal batteries may be, for example, hexagonal batteries.

[0080] At present, when a battery cell experiences thermal runaway, its internal high-temperature gas and high-temperature solid matter are ejected from the pressure relief mechanism. The ejected high-temperature solid matter can easily ignite the combustible gas, causing a fire.

[0081] In this regard, the present application sets a mesh plate between the electrode assembly and the pressure relief mechanism. When the battery cell experiences thermal runaway, the gas inside the battery cell passes smoothly through the mesh holes on the mesh plate and is ejected through the pressure relief mechanism. At the same time, the high-temperature solid matter inside the battery cell is blocked by the mesh plate and cannot pass through the mesh holes on the mesh plate, thereby achieving the purpose of separating the high-temperature solid matter from the gas and solving the problem of high-temperature solid matter igniting combustible gas and causing fire.

[0082] The battery device disclosed in the embodiments of the present application can be used, but is not limited to, in electrical devices such as vehicles, ships, or aircraft. The battery device disclosed in the present application can be used to form a power supply system for the electrical device.

[0083] The technical solutions described in the embodiments of the present application are applicable to various electrical devices that use battery devices, such as mobile phones, portable devices, laptop computers, electric vehicles, electric toys, electric tools, vehicles, ships and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles and spacecraft, etc.

[0084] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device according to an embodiment of the present application.

[0085] Reference Figure 1 Vehicle 1000 may be a fuel-powered vehicle, a gas-powered vehicle, or a new energy vehicle. The new energy vehicle may be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle. A battery device 100 is disposed within vehicle 1000. Battery device 100 may be located at the bottom, front, or rear of vehicle 1000. Battery device 100 may be used to power vehicle 1000. For example, battery device 100 may serve as an operating power source for vehicle 1000 and may be used in the circuit system of vehicle 1000, such as for starting, navigation, and operating the vehicle.

[0086] The vehicle 1000 may further include a controller 200 and a motor 300 . The controller 200 is used to control the battery device 100 to supply power to the motor 300 , for example, to meet the power requirements of the vehicle 1000 during startup, navigation, and driving.

[0087] In some embodiments of the present application, the battery device 100 can serve not only as an operating power source for the vehicle 1000 , but also as a driving power source for the vehicle 1000 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000 .

[0088] Reference Figure 2 The battery device 100 includes a case 10 and a battery cell 20, and the battery cell 20 is accommodated in the case 10. The case 10 is used to provide a storage space for the battery cell 20, and the case 10 can adopt a variety of structures. In some embodiments, the case 10 may include a first sub-case 11 and a second sub-case 12, and the first sub-case 11 and the second sub-case 12 cover each other, and the first sub-case 11 and the second sub-case 12 jointly define a storage space for accommodating the battery cell 20. The second sub-case 12 can be a hollow structure with one end open, and the first sub-case 11 can be a plate-shaped structure, and the first sub-case covers the open side of the second sub-case 12, so that the first sub-case 11 and the second sub-case 12 jointly define a storage space; the first sub-case 11 and the second sub-case 12 can also be hollow structures with one side open, and the open side of the first sub-case 11 covers the open side of the second sub-case 12.

[0089] In the battery device 100, there may be multiple battery cells 20, which may be connected in series, in parallel, or in a hybrid connection. A hybrid connection refers to a combination of series and parallel connections among the multiple battery cells 20. The multiple battery cells 20 may be directly connected in series, in parallel, or in a hybrid connection, and then the entire battery unit 20 may be housed within the housing 10. Alternatively, the battery device 100 may comprise multiple battery cells 20 connected in series, in parallel, or in a hybrid connection to form a battery module, which is then further connected in series, in parallel, or in a hybrid connection to form a single unit and housed within the housing 10. The battery device 100 may also include other structures, such as a busbar assembly for electrically connecting the multiple battery cells 20.

[0090] Reference Figure 3 The battery cell 20 includes a housing 21, an electrode assembly 22, and other functional components. The housing 21 may include a shell 211 and an end cap 212. The shell 211 has an opening, and the end cap 212 closes the opening to isolate the internal environment of the battery cell 20 from the external environment.

[0091] The housing 211 and the end cap 212 cooperate to form an internal environment space for accommodating the battery cell 20, wherein the formed internal environment space can be used to accommodate the electrode assembly 22, electrolyte, and other components. One or more electrode assemblies 22 can be accommodated in the housing 21. The housing 21 can be of various shapes and sizes. Specifically, the shape of the housing 21 can be determined according to the specific shape and size of the electrode assembly. The material of the housing 21 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0092] The end cap 212 can be made of a material with a certain hardness and strength (such as aluminum alloy). In this way, the end cap 212 is not easily deformed when squeezed or collided, so that the battery cell 20 can have a higher structural strength and the reliability can also be improved. The material of the end cap 212 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not impose any special restrictions on this. In some embodiments, an insulating structure can also be provided on the inner side of the end cap 212. The insulating structure can be used to isolate the electrical connection components in the housing 211 from the end cap 212 to reduce the risk of short circuit. Exemplarily, the insulating structure can be plastic, rubber, etc.

[0093] Next, refer to 3 to Figure 9 , the battery cell 20 of the embodiment of the present application is described in detail.

[0094] The present embodiment provides a battery cell 20 comprising a housing 21, an electrode assembly 22, a pressure relief mechanism 23, and a mesh plate 24. The housing 21 includes a first wall 213; the electrode assembly 22 is disposed within the housing 21; the pressure relief mechanism 23 is disposed on the first wall 213; and the mesh plate 24 is insulated and disposed between the electrode assembly 22 and the pressure relief mechanism 23 and is densely packed with multiple meshes.

[0095] The housing 21 is used to accommodate the electrode assembly 22. The first wall 213 can be any wall of the housing 21. In some embodiments, the housing 21 includes a shell 211 and an end cap 212, and the first wall 213 is the end cap 212.

[0096] The electrode assembly 22 is a component where electrochemical reactions occur in the battery cell 20. The housing 21 can accommodate one or more electrode assemblies 22. Figure 3 The figure shows two electrode assemblies 22. The electrode assembly 22 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is provided between the positive and negative electrode sheets to separate the positive and negative electrode sheets to avoid the risk of short circuit between the positive and negative electrode sheets.

[0097] The battery cell 20 may be a square battery cell 20. For example, the electrode assembly 22 may be flat. The thickness direction of the electrode assembly 22 ( Figure 3 The direction of the arrow Y in the middle (the direction in which the arrow Y is located) may be perpendicular to the thickness direction Z of the first wall 213.

[0098] The pressure relief mechanism 23 is used to release the pressure within the battery cell 20 when the pressure or temperature within the battery cell 20 reaches a threshold. In the event of thermal runaway in the battery cell 20, the pressure relief mechanism 23 rapidly opens, reducing the risk of explosion in the battery cell 20. The pressure relief mechanism 23 can take the form of an explosion-proof valve, explosion-proof disk, or pressure relief valve, and can specifically employ a pressure-sensitive element or structure. Specifically, when the internal pressure of the battery cell 20 reaches a predetermined threshold, the pressure relief mechanism 23 activates or a weakened structure within the pressure relief mechanism 23 is destroyed, thereby forming an opening or channel for internal pressure relief.

[0099] The mesh plate 24 is densely provided with a plurality of mesh holes, that is, the mesh plate 24 includes a plate body and at least two rows and at least two columns of mesh holes arranged on the plate body. The mesh plate 24 is a multi-through hole structure. The through holes (mesh holes) on the mesh plate 24 can be circular ( Figure 4 shown), square ( Figure 5The through-holes may be arranged in rectangular or circular arrays, or in other shapes. The shapes of the through-holes may be the same or different, and the sizes of the through-holes may be the same or different. A well-defined through-hole shape facilitates the effective interception of solid matter, such as broken separators, aluminum foil, copper foil, or electrode pieces. Through-holes of varying shapes can effectively intercept different types of solid matter.

[0100] The mesh plate 24 can be connected to the electrode assembly 22, for example, by bonding. In some embodiments, the mesh plate 24 can be an insulating plate. The melting point of the insulating plate is greater than or equal to 200°C, such as 200°C, 300°C, 400°C, 500°C or 600°C. For example, the material of the insulating plate can be polyimide, polyetheretherketone, polyphenylene sulfide, ceramic (aluminum oxide, silicon nitride, etc.), high temperature resistant epoxy resin, glass fiber, etc., or glass fiber reinforced composite, alumina fiber reinforced mullite and other composite materials. In other embodiments, refer to Figure 6 The mesh plate 24 includes a base 243 and an insulating layer 244 covering the base 243. The melting point of the base 243 is greater than or equal to 600°C, for example, 600°C, 700°C, 800°C, 900°C, or 1000°C. The base can be made of a material with a relatively high melting point, such as copper, tungsten, titanium, iron, nickel, or cobalt. The insulating layer 244 can be made of a coating such as PE (polyethylene), PP (polypropylene), PET (polyethylene terephthalate), aluminum oxide, silicon dioxide, or zirconium oxide.

[0101] The thickness of the mesh plate 24 can be 0.05 mm to 10 mm, for example, 0.05 mm, 1 mm, 2 mm, 3.5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 10 mm. When the thickness of the mesh plate is 0.05 mm to 10 mm, it can have good impact resistance and reduce space occupation, which is conducive to improving the volume energy density of the battery.

[0102] Optionally, the thickness of the mesh plate 24 may be 0.06 mm to 3 mm, for example, 0.06 mm, 0.5 mm, 1 mm, 2 mm or 3 mm.

[0103] The mesh plate 24 is made of a high-temperature resistant insulating material or is covered with an insulating material on its surface, ensuring the insulation of the battery cell 20 during normal use. In the event of thermal runaway of the battery cell 20, the mesh holes in the mesh plate 24 allow a large amount of gas released from the battery cell 20 to pass smoothly and be ejected through the pressure relief mechanism 23. At the same time, the limited size of the mesh holes blocks the solid matter inside the battery cell 20, thereby reducing the risk of fire caused by the ejection of high-temperature solid matter from the battery cell 20 igniting combustible gases.

[0104] In some embodiments, along the thickness direction Z of the first wall 213, the projection of the mesh plate 24 on the first wall 213 completely covers the pressure relief mechanism 23. That is, the outer contour of the pressure relief mechanism 23 is located within the outer contour of the projection of the mesh plate 24 on the first wall 213. The projection of the mesh plate 24 on the first wall 213 includes the projection of the plate body and the projection of the meshes.

[0105] Therefore, in the event of thermal runaway of the battery cell 20, the gas ejected from the pressure relief mechanism 23 passes through the mesh plate 24, effectively preventing the solid matter inside the battery cell 20 from being ejected from the pressure relief mechanism 23, achieving solid-gas separation, and reducing the risk of fire caused by the ejection of high-temperature solid matter inside the battery cell 20 igniting combustible gas.

[0106] In some embodiments, the first wall 213 is provided with an injection hole 25; along the thickness direction Z of the first wall 213, the projection of the mesh plate 24 on the first wall 213 completely covers the injection hole 25, that is, the outer contour of the injection hole 25 is located within the outer contour of the projection of the mesh plate 24 on the first wall 213.

[0107] The injection hole 25 is used for injecting electrolyte. After the injection is completed, a plugging member can be set at the injection hole 25 to seal the injection hole 25. As an example, the area of ​​a single mesh on the mesh plate 24 can be smaller than the area of ​​the injection hole 25.

[0108] The projection of the mesh plate 24 on the first wall 213 along the thickness direction Z of the first wall 213 completely covers the injection hole 25. During the injection process, the electrolyte flows into the outer shell 21 through the mesh holes on the mesh plate 24, so that the electrode assembly is more fully soaked. It can also reduce the impact force of the liquid on the electrode assembly 22, reduce the risk of damage to the electrode assembly 22, and improve the reliability of the battery cell 20.

[0109] In some embodiments, the electrode assembly 22 includes an electrode body 221 and a tab 222, and the tab 222 is arranged on the first end surface 22a of the electrode body 221; the battery cell 20 also includes an adapter 26 and an electrode terminal 27, and the electrode terminal 27 is arranged on the first wall 213, and the adapter 26 connects the tab 222 and the electrode terminal 27; along the thickness direction Z of the first wall 213, the mesh plate 24 is located between the adapter 26 and the first end surface 22a.

[0110] The electrode body 221 is a main part of the electrode assembly 22 , and the electrode body 221 and the tab 222 may be an integral structural component.

[0111] The electrode terminal 27 is a component that draws current from the battery cell 20. Two electrode terminals 27 can be provided, namely a positive terminal and a negative terminal. The electrode terminal 27 can be a riveted pole, etc.

[0112] The adapter 26 is used to electrically connect the tab 222 and the electrode terminal 27. The adapter 26 can be made of aluminum sheet or the like.

[0113] The mesh plate 24 is located between the adapter 26 and the first end face 22a. When the pole ear 222 is bent, for example, when the end cover 212 is pressed onto the open end of the shell 211 so that the pole ear 222 is bent, or when the pole ears 222 of multiple electrode assemblies 22 are connected through the adapter 26 and then docked so that the pole ears 222 are bent, the mesh plate 24 can prevent the root of the pole ear 222 from being inserted into the first end face 22a of the electrode body 221, thereby reducing the risk of short circuit.

[0114] In some embodiments, the tabs 222 include a positive tab 2221 and a negative tab 2222. The positive tab 2221 and the negative tab 2222 are spaced apart along a first direction X, which is perpendicular to the thickness direction Z of the first wall 213. Along the first direction X, the size of the mesh plate 24 is greater than the spacing between the positive tab 2221 and the negative tab 2222. The first direction X may be the length direction of the battery cell 20.

[0115] As an example, along the first direction X, both ends of the mesh plate 24 may extend beyond or flush with the edges of the positive electrode tab 2221 and the negative electrode tab 2222 . Furthermore, the mesh plate 24 may completely cover the first end surface 22 a of the electrode body 221 .

[0116] By making the size of the mesh plate 24 larger than the spacing distance between the positive electrode tab 2221 and the negative electrode tab 2222, the area ratio of the mesh plate 24 to the first end face 22a can be increased. In the event of thermal runaway of the battery cell 20, more solid matter can be blocked, reducing the risk of solid matter escape, and further reducing the risk of fire caused by the ejection of high-temperature solid matter inside the battery cell 20 igniting combustible gas.

[0117] In some embodiments, reference Figure 5 and Figure 9 The mesh plate 24 is provided with a first notch 241 and a second notch 242 , the positive electrode tab 2221 is located in the first notch 241 , and the negative electrode tab 2222 is located in the second notch 242 .

[0118] The size of the first notch 241 can be adapted to the size of the base of the positive electrode tab 2221 , and the size of the second notch 242 can be adapted to the size of the base of the negative electrode tab 2222 .

[0119] By cooperating with the positive electrode tab 2221 and the negative electrode tab 2222 respectively through the first notch 241 and the second notch 242, the displacement of the mesh plate 24 can be limited. When the tab 222 is bent, the mesh plate 24 can more reliably block the root of the tab 222 from being inserted into the first end face 22a of the electrode body 221, further reducing the risk of short circuit.

[0120] In some embodiments, the mesh plate 24 and the first end surface 22a are bonded together by an adhesive 28 ( Figure 8 as shown) connections.

[0121] The adhesive member 28 may be a high temperature resistant insulating tape, an insulating colloid, etc. The mesh plate 24 may be bonded to the first end surface 22 a before the tab 222 is bent.

[0122] The mesh plate 24 is connected to the first end surface 22 a via an adhesive 28 , which can improve the installation firmness of the mesh plate 24 and further reduce the risk of displacement of the mesh plate 24 .

[0123] In some embodiments, the ratio of the sum of the areas of all meshes on the mesh plate 24 to the area of ​​the mesh plate 24 is greater than or equal to 0.2.

[0124] The area of ​​the mesh plate 24 is the area enclosed by the closed outer contour formed by the projection of the mesh plate 24 .

[0125] Therefore, the larger mesh area ratio can make the mesh plate 24 exhaust more smoothly.

[0126] In some embodiments, the area of ​​a single mesh on the mesh plate 24 is less than or equal to 1 cm 2 , for example 0.1cm 2 , 0.3cm 2 , 0.5cm 2 , 0.8cm 2 or 1cm 2 wait.

[0127] Reasonable single mesh size is conducive to the effective interception of solid particles, such as broken isolation membranes, broken aluminum foil, broken copper foil, broken electrodes, etc.

[0128] In a second aspect, an embodiment of the present application provides a battery device 100 , comprising a battery cell 20 according to any of the above embodiments.

[0129] In a third aspect, an embodiment of the present application provides an electrical device, comprising the battery cell 20 of any of the above embodiments, or the battery device 100 as described above.

[0130] Next, refer to 3 to Figure 9 , a specific example of this application is described.

[0131] An embodiment of the present application provides a battery cell 20, comprising a housing 21, an electrode assembly 22, a pressure relief mechanism 23, and a mesh plate 24. The housing 21 comprises a first wall 213, which serves as an end cap 212. The pressure relief mechanism 23 is disposed on the first wall 213. The electrode assembly 22 is disposed within the housing 21, and comprises an electrode body 221 and tabs 222, wherein the tabs 222 comprise a positive electrode tab 2221 and a negative electrode tab 2222. The positive electrode tab 2221 and the negative electrode tab 2222 are both connected to the first end surface 22a of the electrode body 221. The mesh plate 24 is located between the electrode assembly 22 and the pressure relief mechanism 23.

[0132] The mesh plate 24 can have a thickness of 0.05mm to 10mm. It is constructed of a high-temperature resistant insulating material or covered with an insulating material to ensure safety and insulation during normal use. In the event of thermal runaway of a battery cell 20, the mesh structure of the mesh plate 24 allows the large amount of gas released from within the battery cell 20 to pass smoothly. At the same time, the limited mesh size prevents the escape of larger solid matter from within the battery cell 20, thus preventing the ignition of combustible fumes from the escape of high-temperature solid matter from within the battery cell 20.

[0133] To ensure smooth exhaust, the sum of all mesh holes on the mesh plate 24 should account for ≥ 20% of the area of ​​the mesh plate 24. To effectively block solid matter, the area of ​​a single mesh hole on the mesh plate 24 should be ≤ 1 cm². The mesh holes on the mesh plate 24 can be rectangular, circular, triangular, polygonal, or a combination thereof, and can be arranged in a rectangular array, an annular array, or other configurations.

[0134] The material of the mesh plate 24 is made of a material with a melting point of more than 200°C, such as polyimide, polyetheretherketone, polyphenylene sulfide, ceramic materials (aluminum oxide, silicon nitride, etc.), high-temperature epoxy resin, glass fiber, etc., or a composite form of different materials, such as glass fiber reinforced composite material (glass fiber / PPS), alumina fiber reinforced mullite, high-temperature metal + plasma sprayed insulation coating.

[0135] The mesh plate 24 can also be made of a high-temperature resistant substrate + an insulating layer. The substrate material must have a temperature tolerance of ≥600°C and can be made of high-melting-point materials such as copper, tungsten, titanium, iron, nickel, and cobalt. The insulating layer can be made of polymers such as engineering plastics, PE, PP, and PET, or oxide coatings such as aluminum oxide, silicon dioxide, and zirconium oxide. The insulating layer must completely cover the metal substrate to meet insulation requirements.

[0136] The positive electrode sheet, negative electrode sheet, and separator are fabricated into an electrode assembly core using a winding or lamination process. During the battery cell assembly process, a mesh plate 24 can be installed before the tab folding process. It is installed between the electrode assembly 22 and the pressure relief mechanism 23. The mesh plate 24 completely covers the projection of the pressure relief mechanism 23 in the thickness direction Z of the first wall 213, ensuring that the airflow ejected from the explosion-proof valve passes through the mesh plate 24 for solid-gas separation. The mesh plate 24 can be directly fixed in place using high-temperature resistant tape to prevent movement. The mesh plate 24 provides support and filtering, effectively preventing solid matter from being ejected from the battery cell 20 during thermal runaway. The mesh plate 24 also prevents the tab from being inserted into the electrode assembly 22, reducing the risk of short circuits. Furthermore, the mesh plate 24 is provided with an opening that locks with the tab 222, further limiting the position of the mesh plate 24 and preventing the tab from being inserted into the electrode assembly 22.

[0137] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and components may be substituted with equivalents without departing from the scope of the present application. In particular, the various technical features described in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the present application.

Claims

1. A battery cell, characterized in that: include: a housing comprising a first wall; an electrode assembly, disposed in the housing; a pressure relief mechanism, disposed on the first wall; A mesh plate, which can be insulated and disposed between the electrode assembly and the pressure relief mechanism and is densely provided with a plurality of mesh holes; The electrode assembly includes an electrode body and a tab, wherein the tab is provided on a first end surface of the electrode body; The battery cell further includes a connecting piece and an electrode terminal, wherein the electrode terminal is provided on the first wall, and the connecting piece connects the tab and the electrode terminal; Along the thickness direction of the first wall, the mesh plate is located between the adapter and the first end surface.

2. The battery cell according to claim 1, wherein: The mesh plate is an insulating plate, or the mesh plate includes a base and an insulating layer covering the base.

3. The battery cell according to claim 1, wherein: Along the thickness direction of the first wall, the projection of the mesh plate on the first wall completely covers the pressure relief mechanism.

4. The battery cell according to claim 1, wherein: The first wall is provided with a liquid injection hole; Along the thickness direction of the first wall, the projection of the mesh plate on the first wall completely covers the injection hole.

5. The battery cell according to claim 1, characterized in that The tabs include a positive tab and a negative tab, the positive tab and the negative tab are spaced apart along a first direction, and the first direction is perpendicular to the thickness direction of the first wall; Along the first direction, the size of the mesh plate is larger than the spacing distance between the positive electrode tab and the negative electrode tab.

6. The battery cell according to claim 5, characterized in that The mesh plate is provided with a first notch and a second notch, the positive electrode tab is located in the first notch, and the negative electrode tab is located in the second notch.

7. The battery cell according to claim 1, characterized in that The mesh plate is connected to the first end surface via an adhesive.

8. The battery cell according to claim 1, wherein: The ratio of the sum of the areas of all meshes on the mesh plate to the area of ​​the mesh plate is greater than or equal to 0.

2.

9. The battery cell according to claim 1, characterized in that The area of ​​a single mesh on the mesh plate is less than or equal to 1 cm 2 .

10. The battery cell according to claim 1, characterized in that The thickness of the mesh plate is 0.05 mm to 10 mm.

11. The battery cell according to claim 10, characterized in that The thickness of the mesh plate is 0.06 mm to 3 mm.

12. The battery cell according to claim 2, characterized in that: The melting point of the insulating plate is greater than or equal to 200°C.

13. The battery cell according to claim 12, characterized in that: The insulating plate is made of polyimide, polyetheretherketone, polyphenylene sulfide, ceramic, epoxy resin, glass fiber, glass fiber reinforced composite or alumina fiber reinforced mullite.

14. The battery cell according to claim 2, characterized in that The melting point of the substrate is greater than or equal to 600°C.

15. The battery cell according to claim 14, characterized in that The substrate is made of copper, tungsten, titanium, iron, nickel or cobalt; The insulating layer is made of PE, PP, PET, aluminum oxide, silicon dioxide or zirconium oxide.

16. A battery device, characterized in that: include: A battery cell according to any one of claims 1 to 15.

17. An electrical device, characterized in that: include: The battery cell according to any one of claims 1 to 15, or the battery device according to claim 16.

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