Battery cell, battery device, energy storage device, energy storage system and charging network

Abstract

The invention provides a battery cell, a battery device, an energy storage device, an energy storage system and a charging network. Each single battery comprises a shell, an electrolyte, a pressure relief mechanism, a collection part and an atomization part, the shell is provided with a containing cavity and comprises a first wall, and the first wall is arranged on one side, in the first direction, of the containing cavity. The electrolyte is contained in the containing cavity, and the pressure relief mechanism is arranged on the first wall. The collecting component is connected to the side, facing the containing cavity, of the first wall and provided with a cavity, an opening is formed in the side, facing the first wall, of the collecting component and communicated with the cavity, the collecting component comprises a side wall, the side wall surrounds the opening, a through hole is formed in the side wall, and the cavity and the containing cavity are communicated through the through hole. At least part of the atomizing part is arranged in the cavity, and the atomizing part is configured to atomize the electrolyte and spray the electrolyte towards the pressure relief mechanism when the battery monomer reaches a preset state. According to the invention, the reliability of the battery monomer can be effectively improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a battery monomer, a battery device, an energy storage device, an energy storage system and a charging network. BACKGROUND

[0002] With the development of new energy technology, batteries are increasingly widely used, for example, in mobile phones, notebook computers, electric cars, electric vehicles, electric aircraft, electric ships, electric toy cars, electric toy ships, electric toy aircraft and electric tools.

[0003] In the development of battery technology, how to improve the reliability of the battery monomer is a continuous research direction in battery technology. SUMMARY

[0004] In view of the above problems, the present application provides a battery monomer, a battery device, an energy storage device, an energy storage system and a charging network, which can effectively improve the reliability of the battery monomer.

[0005] In a first aspect, the embodiments of the present application provide a battery monomer, which comprises a shell, an electrolyte, a pressure relief mechanism, a collection component and an atomization component. The shell has a receiving cavity. The shell comprises a first wall, which is arranged on one side of the receiving cavity along a first direction. The electrolyte is contained in the receiving cavity, and the pressure relief mechanism is arranged on the first wall. The collection component is connected to the side of the first wall facing the receiving cavity. The collection component has a cavity. The side of the collection component facing the first wall is provided with an opening, and the opening is in communication with the cavity. In the same plane perpendicular to the first direction, the orthographic projection of the pressure relief mechanism and the orthographic projection of the opening at least partially overlap. The collection component comprises a side wall, which is arranged around the opening. A through hole is formed in the side wall and is in communication with the cavity and the receiving cavity. At least part of the atomization component is arranged in the cavity. The atomization component is configured to atomize the electrolyte and spray it towards the pressure relief mechanism when the battery monomer reaches a preset state.

[0006] The above technical solution can atomize the electrolyte and spray it towards the pressure relief mechanism when the battery monomer produces thermal runaway, and the temperature, pressure and electrolyte level inside the battery monomer will rise sharply. When the battery monomer reaches the preset state, the atomization component can atomize the electrolyte and spray it towards the pressure relief mechanism. The atomized electrolyte has a large specific surface area and can instantly absorb the heat of the surrounding environment (especially the high-temperature area near the pressure relief mechanism) and evaporate violently. The evaporation process absorbs a large amount of heat and produces a strong local cooling effect, thereby effectively reducing the risk of combustion and improving the reliability of the battery monomer.

[0007] In addition, by introducing the collection component, the collection component can collect more electrolyte to the action area of the atomization component, which can increase the atomization amount of the atomization component when the battery monomer produces thermal runaway, thereby further reducing the risk of combustion when the battery monomer produces thermal runaway and improving the reliability of the battery monomer.

[0008] In some embodiments of the first aspect, the atomization component is configured to atomize and eject the electrolyte towards the pressure relief mechanism when the pressure in the accommodation cavity reaches a first threshold value; and / or, the atomization component is configured to atomize and eject the electrolyte towards the pressure relief mechanism when the temperature in the accommodation cavity reaches a second threshold value.

[0009] The change process of the temperature and the pressure can directly reflect the evolution of the thermal state inside the battery cell, and triggering the atomization mechanism by the temperature and / or the pressure facilitates passive triggering of the atomization component, which can achieve a more concise structural design and is conducive to cost reduction.

[0010] In addition, the temperature signal and the pressure signal are easy to collect and have clear change trends, and are not easily disturbed by short-time vibration or mechanical stress and the like. Therefore, by triggering the atomization mechanism by the temperature and / or the pressure, more accurate control can be achieved under the active triggering scheme of the atomization component, and the reliability of the atomization component can be improved.

[0011] In some embodiments of the first aspect, the atomization component is arranged on a side of the pressure relief mechanism facing the accommodation cavity.

[0012] During the process of thermal runaway of the battery cell and ejection of the electrolyte from the pressure relief mechanism, the atomization component can be located on the ejection path of the electrolyte, so that the atomization component can atomize the electrolyte more quickly at the critical moment of thermal runaway of the battery cell, and rapid intervention cooling can be achieved, thereby effectively improving the response speed of the atomization component.

[0013] In some embodiments of the first aspect, a projection of the atomization component and a projection of the opening at least partially overlap in a same plane perpendicular to the first direction.

[0014] The fine droplets formed by the atomization of the atomization component can be ejected to the opening along a shorter path and in a smaller deviation direction. The ejection concentration of the atomization component is significantly improved, and the lateral diffusion of the mist droplets in the cavity is reduced, thereby further improving the cooling effect of the atomization component on the position of the pressure relief mechanism when the battery cell is in thermal runaway.

[0015] In some embodiments of the first aspect, the atomization component is arranged at an end of the collection component away from the pressure relief mechanism. The risk of impact damage to the atomization component during opening of the pressure relief mechanism can be reduced.

[0016] In some embodiments of the first aspect, a side surface of the side wall facing the cavity is a tapered surface gradually shrinking in a direction away from the pressure relief mechanism.

[0017] The conical surface can guide the mist sprayed by the atomizing component to spread in the direction towards the opening, so that a high-density mist belt can be formed when the mist reaches the opening, thereby forming a larger cooling coverage at the position of the pressure relief mechanism and the collecting component, so as to further reduce the risk of combustion when the battery monomer is in thermal runaway.

[0018] In some embodiments of the first aspect, the collecting component further comprises a bottom wall located on the side of the cavity away from the opening, the bottom wall being connected to the side wall, and the atomizing component being connected to the bottom wall.

[0019] The above technical solution further introduces a bottom wall, which can provide a stable installation basis for the atomizing component, thereby reducing the installation difficulty of the atomizing component and improving the structural stability of the atomizing component.

[0020] In some embodiments of the first aspect, the battery monomer further comprises a flow guide pipe, one end of the flow guide pipe being connected to the collecting component and communicating with the cavity, and the other end of the flow guide pipe being farther away from the first wall in the first direction relative to the collecting component.

[0021] In the initial stage of thermal runaway of the battery monomer, the temperature inside the battery monomer rises rapidly, and the electrolyte can be more rapidly collected into the cavity through the flow guide pipe, thereby providing a timely source of electrolyte for the atomizing component, so as to improve the response speed of the atomizing component.

[0022] In some embodiments of the first aspect, the end of the flow guide pipe away from the collecting component is inserted into the electrolyte. This can further improve the timeliness of the electrolyte entering the cavity and further improve the response speed of the atomizing component.

[0023] In some embodiments of the first aspect, the battery monomer further comprises a blocking component connected to the collecting component and closing the opening. The blocking component is configured to break when the battery monomer reaches a preset state to communicate the cavity and the pressure relief mechanism.

[0024] In the normal working state of the battery monomer, the blocking component closes the opening, which can isolate the atomizing component from the internal environment of the battery monomer, thereby reducing the risk of failure of the atomizing component due to the influence of the internal environment of the battery monomer. When the battery monomer reaches a preset state, such as thermal runaway, the blocking component will break, thereby exposing the opening to communicate the cavity and the pressure relief mechanism, thereby providing conditions for the atomizing component to spray mist into the pressure relief mechanism.

[0025] In some embodiments of the first aspect, the number of atomizing components is multiple, and at least part of the multiple atomizing components is arranged along the outer contour of the pressure relief mechanism.

[0026] The plurality of atomizing components arranged along the outer contour of the pressure relief mechanism can spray the pressure relief mechanism at different orientations to improve the overall coverage of the mist droplets, thereby further improving the cooling effect of the atomizing components on the position of the pressure relief mechanism when the battery cell is in thermal runaway. In addition, the plurality of atomizing components can form a mist droplet overlapping area, thereby further improving the local cooling effect.

[0027] In a second aspect, the present application provides a battery device comprising the battery cell according to any one of the embodiments of the first aspect.

[0028] In a third aspect, the present application provides an energy storage device comprising a plurality of battery cells according to any one of the embodiments of the first aspect or a plurality of battery devices according to any one of the embodiments of the second aspect, wherein the battery cells or the battery devices are used to store or provide electrical energy.

[0029] In a fourth aspect, the present application provides an energy storage system comprising an energy conversion system and an energy storage device according to any one of the embodiments of the third aspect, wherein the energy conversion system is connected to the energy storage device to convert the electrical current input into or output from the energy storage device.

[0030] In a fifth aspect, the present application provides a charging network comprising a charging pile and an energy storage device according to any one of the embodiments of the third aspect or an energy storage system according to any one of the embodiments of the fourth aspect, wherein the energy storage device is used to provide electrical energy for the charging pile.

[0031] The above description is only a summary of the technical solutions of the present application. In order to enable the technical means of the present application to be more clearly understood, and to be implemented according to the content of the description, and in order to enable the above and other purposes, characteristics and advantages of the present application to be more apparent and easy to understand, the following specific embodiments of the present application are described. BRIEF DESCRIPTION OF DRAWINGS

[0032] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a description of the preferred embodiments and are not meant to limit the present application. Moreover, the same reference numerals in the attached drawings indicate the same or similar components. In the drawings: Figure 1 Structure diagram of a charging network according to some embodiments of the present application; Figure 2 Structure diagram of an energy storage system according to some embodiments of the present application; Figure 3 Exploded structure diagram of a battery device according to some embodiments of the present application; Figure 4 Structure diagram of a battery module according to some embodiments of the present application; Figure 5A perspective view of a battery cell according to some embodiments of the present application; Figure 6 A top view of a battery cell according to some embodiments of the present application; Figure 7 A perspective view of a battery cell according to some embodiments of the present application; Figure 6 A cross-sectional view along A-A; Figure 8 A top view of a first wall of a battery cell according to some embodiments of the present application; Figure 9 A cross-sectional view of a first wall of a battery cell according to some embodiments of the present application along B-B; Figure 8 A cross-sectional view of a first wall of another battery cell according to some embodiments of the present application along B-B; Figure 10 Figure 8 A cross-sectional view of a first wall of yet another battery cell according to some embodiments of the present application along B-B; Figure 11 A cross-sectional view of a first wall of still another battery cell according to some embodiments of the present application along B-B; Figure 8 A cross-sectional view of a first wall of yet another battery cell according to some embodiments of the present application along B-B; Figure 12 Figure 8 A cross-sectional view of a first wall of still another battery cell according to some embodiments of the present application along B-B.

[0033] Reference signs in the detailed description of the embodiments are as follows: 100, energy storage device; 200, energy conversion system; 300, power generation equipment; 400, charging pile; 500, connector; 2, battery device; 5, box body; 5a, first box body; 5b, second box body; 6, battery module; 7, battery cell; 10, shell; 11, containing cavity; 12, first wall; 20, electrolyte; 30, pressure relief mechanism; 40, atomization component; 50, collection component; 51, cavity; 52, opening; 53, side wall; 531, through hole; 54, bottom wall; 60, drainage pipe; 70, plugging component; X, first direction. DETAILED DESCRIPTION

[0034] ​​To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0035] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the specification of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the specification, claims, and foregoing drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the specification, claims, or foregoing drawings of this application are used to distinguish different objects, rather than to describe a specific order or hierarchy.

[0036] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0037] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0038] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0039] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0040] In this application, "multiple" means two or more (including two).

[0041] In this application, the term "parallel" includes not only the case of absolute parallelism, but also the case of approximate parallelism as commonly understood in engineering; similarly, "perpendicular" includes not only the case of absolute perpendicularity, but also the case of approximate perpendicularity as commonly understood in engineering.

[0042] With the development of new energy technologies, batteries are being used more and more widely, for example in mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, and power tools.

[0043] In the development of battery technology, improving the reliability of individual battery cells is an ongoing research direction.

[0044] In related technologies, when a battery cell experiences thermal runaway, a large amount of gas is generated inside the cell. After the pressure relief mechanism is activated under high internal pressure, a large amount of high-temperature, flammable electrolyte is ejected along with the high-pressure gas. When this electrolyte comes into contact with external air or encounters high temperatures or sparks near the pressure relief port, it will burn rapidly, forming a continuous flame, which reduces the reliability of the battery cell.

[0045] Based on the above considerations, this application designs a battery cell, which includes a casing, an electrolyte, a pressure relief mechanism, and an atomizing component. The casing has a receiving cavity in which the electrolyte is contained. The pressure relief mechanism is disposed in the casing, and the atomizing component is contained in the receiving cavity and connected to the casing. The atomizing component is configured to atomize the electrolyte and spray it toward the pressure relief mechanism when the battery cell reaches a preset state.

[0046] When a battery cell experiences thermal runaway, the internal temperature and pressure rise sharply. When the cell reaches a preset state, the atomizing component atomizes the electrolyte and sprays it towards the pressure relief mechanism. The atomized electrolyte has a very large specific surface area, allowing it to instantly absorb heat from the surrounding environment (especially the high-temperature area near the pressure relief mechanism) and evaporate rapidly. This evaporation process absorbs a large amount of heat, generating a strong localized cooling effect, effectively reducing the risk of combustion and improving the reliability of the battery cell.

[0047] Figure 1 This is a schematic diagram of the charging network structure in some embodiments of this application. Figure 2 This is a schematic diagram of the energy storage system in some embodiments of this application.

[0048] like Figure 1 and Figure 2As shown, this application embodiment provides a charging network including a charging pile 400 and an energy storage device 100. The charging pile 400 is electrically connected to the energy storage device 100, which provides electrical energy to the charging pile 400. The charging pile 400 is electrically connected to a battery device in the energy storage device 100 via a cable, and the battery device can provide its stored electrical energy to the charging pile 400. The charging pile 400 has one or more connectors 500 for connecting to electrical equipment (such as a vehicle), thereby enabling the charging equipment to receive additional power.

[0049] Energy storage devices can be located inside the charging pile (e.g., an integrated energy storage and charging unit) or outside the charging pile.

[0050] In some embodiments, the energy storage system may include one or more energy storage devices 100 and a power converter system (PCS). The power converter system 200 is used to connect the power generation device 300, the power grid, or a load to the energy storage device 100. The power generation device 300 generates electrical energy, the energy storage device 100 stores electrical energy, and the power converter system 200 converts the current input to the energy storage device 100 or the current output from the energy storage device 100 into energy. The electrical energy generated by the power generation device 300 can be stored in the energy storage device 100 through the power converter system 200, and the electrical energy stored in the energy storage device 100 can also be output to the load or the power grid through the power converter system 200. As an example, the power generation device 300 may specifically be a solar panel, a hydroelectric power generation device, a thermal power generation device, a wind power generation device, etc. The specific type of the power generation device 300 is not limited in this application.

[0051] In some embodiments, the charging network may include a charging pile 400 and an energy storage system, wherein the charging pile 400 is electrically connected to the energy storage device 100 in the energy storage system.

[0052] This application provides an energy storage device 100, including one or more battery clusters to increase the voltage and capacity of the energy storage device 100. A battery cluster may include multiple battery devices, which are connected in series via a busbar to increase the voltage of the energy storage device. When the energy storage device includes multiple battery clusters, the multiple battery clusters are connected in parallel to increase the capacity of the energy storage device 100.

[0053] The energy storage device 100 can be used in energy storage power stations, wind power generation systems, solar power generation systems, mobile power systems, or temporary power supply systems, etc. The energy storage device 100 can store electrical energy as needed and output it when appropriate. For example, the energy storage device 100 can store electrical energy during off-peak hours and provide power to relevant users or electrical equipment during peak hours. The energy storage system provided in this application embodiment can be any power system that requires the use of the energy storage device 100.

[0054] In some embodiments, the energy storage device 100 is an energy storage container or an energy storage cabinet.

[0055] In some embodiments, the energy storage device 100 may include a cabinet and one or more battery clusters housed in the cabinet.

[0056] In some embodiments, the energy storage device 100 may include modules such as a thermal management module, a main control module, a central control module, a power distribution module, and a fire protection module.

[0057] As an example, the thermal management module may include a liquid cooling unit that supplies coolant to each battery device via piping to regulate the temperature of the individual battery cells.

[0058] As an example, the main control module can serve as the battery management unit for the battery cluster, used to monitor and manage the battery cluster. The main control module can monitor information such as the current, voltage, power, or temperature of the battery cluster. For instance, it can control the charging and discharging current and voltage of the battery cluster. The main control module includes modules such as an auxiliary battery management unit (SBMU) and a fusion switch.

[0059] As an example, the central control module can serve as the battery management unit of the energy storage device 100, used to monitor and manage the energy storage device 100. The central control module can monitor information such as the current, voltage, power, state of charge, or temperature of the energy storage device 100. For example, it can control the charging and discharging current and voltage of the energy storage device 100. As an example, the central control module includes modules such as an insulation monitoring module (IMM), a master battery management unit (MBMU), an Ethernet (ETH) module, and a fiber optic conversion module.

[0060] As an example, a fire protection system includes control panels, detectors, alarm devices, etc., used to detect, alarm, or extinguish fires in energy storage systems.

[0061] As an example, the power distribution device can be used to distribute power to the power modules of the energy storage device 100.

[0062] Figure 3 This is an exploded structural diagram of a battery device provided in some embodiments of this application.

[0063] In some embodiments, the battery device 2 may include one or more battery cell assemblies for providing voltage and capacity.

[0064] A battery cell assembly may include multiple battery cells ( Figure 2 (Not shown) Multiple battery cells are connected in series, parallel, or mixed connection through a busbar. Mixed connection refers to multiple battery cells being connected in both series and parallel.

[0065] A battery cell can be a rechargeable battery cell, which refers to a battery cell that can be recharged after being discharged to activate the active materials and continue to be used.

[0066] As an example, a single battery cell can be a lithium-ion battery cell, a sodium-ion battery cell, a sodium-lithium-ion battery cell, a lithium metal battery cell, a sodium metal battery cell, a lithium-sulfur battery cell, a magnesium-ion battery cell, a nickel-metal hydride battery cell, a nickel-cadmium battery cell, a lead-acid battery cell, etc.

[0067] As an example, a battery cell can be a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic battery cells, such as hexagonal prismatic battery cells.

[0068] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells; as an example, a battery cell assembly can be a battery module 6, which is formed by arranging and fixing multiple battery cells into a single module. As an example, a battery module 6 can be formed by bundling multiple battery cells together with cable ties.

[0069] In some embodiments, the battery device 2 may be a battery pack, which includes a housing 5 and one or more battery cell assemblies housed within the housing 5. As an example, the battery cell assembly may be a battery module 6, which can be housed within the housing by securing the battery module 6 to the housing. Alternatively, the battery cell assembly may be housed within the housing by directly securing multiple battery cells to the housing.

[0070] In some embodiments, the housing 5 is used to house individual battery cells, and the housing 5 can have various structures.

[0071] In some embodiments, the housing 5 may include a first housing 5a and a second housing 5b. The first housing 5a and the second housing 5b are fastened together to form a closed space inside the housing 5 to house the battery cell assembly. Here, "closed" refers to covering or closing, and can be either sealed or unsealed. The first housing may be a top cover or a bottom plate.

[0072] In some embodiments, the housing 5 may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are respectively connected to the frame, forming an enclosed space inside the housing to accommodate individual battery cells. As an example, the frame may include multiple side beams.

[0073] In some embodiments, the housing 5 may be part of the vehicle's chassis structure. For example, a portion of the housing 5 may be at least a portion of the vehicle's floor, or a portion of the housing 5 may be at least a portion of the vehicle's crossbeams and longitudinal beams.

[0074] Figure 4 This is a schematic diagram of the structure of a battery module provided in some embodiments of this application.

[0075] In some embodiments, such as Figure 4 As shown, there are multiple battery cells 7, which are first connected in series, parallel, or a combination of both to form a battery module 6. These battery modules 6 are then connected in series, parallel, or a combination of both to form a whole, which is housed within the casing.

[0076] Multiple battery cells 7 in battery module 6 can be electrically connected through a busbar to achieve parallel, series, or mixed connection of multiple battery cells 7 in battery module 6. There can be one or more busbars, each used to electrically connect at least two battery cells 7.

[0077] This application provides a battery cell that includes a housing and an electrode assembly housed within the housing.

[0078] In some embodiments, the outer casing may be a steel casing, an aluminum casing, or a composite metal casing (such as a copper-aluminum composite casing).

[0079] The outer shell can be a hollow structure, with an internal cavity for accommodating the electrode assembly and electrolyte.

[0080] In some embodiments, the casing of the battery cell is a cylindrical casing, a square casing, a prismatic casing, or a casing of other shapes.

[0081] The housing can come in various shapes and sizes, such as cuboid or cylindrical. Specifically, the shape of the housing can be determined based on the specific shape and size of the electrode assembly. The housing can be made of various materials, such as copper, iron, aluminum, stainless steel, and aluminum alloy.

[0082] The shape of the end cap can be adapted to the shape of the housing to fit the housing. The material of the end cap can be the same as or different from that of the housing. Optionally, the end cap can be made of a material with a certain degree of hardness and strength (such as copper, iron, aluminum, stainless steel, aluminum alloy, etc.), so that the end cap is not easily deformed when subjected to compression and impact, enabling the battery cell to have higher strength and improve reliability.

[0083] The end caps are attached to the housing by welding, bonding, snap-fitting, or other means.

[0084] Electrode assemblies are the components within a single battery cell where electrochemical reactions occur. The casing may contain one or more electrode assemblies.

[0085] In some embodiments, the electrode assembly includes a positive electrode and a negative electrode, wherein the positive electrode and the negative electrode have opposite polarities.

[0086] In some embodiments, the positive electrode may include a positive current collector and a positive electrode film layer disposed on at least one surface of the positive current collector.

[0087] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive electrode film layer is disposed on either or both of the two opposite surfaces of the positive current collector.

[0088] As an example, the positive current collector can be a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as a metal foil, pure metals, alloys, or surface-treated metals can be used, including but not limited to stainless steel, copper, aluminum, nickel, nickel alloys, titanium, or silver. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0089] As an example, the positive electrode film layer includes a positive electrode active material, which may include at least one of the following materials: lithium phosphate, lithium transition metal oxide, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials for batteries may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphate include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites. Examples of lithium transition metal oxides include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (such as LiNi). 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523 LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM) 811 ), lithium nickel cobalt aluminum oxide (such as LiNi) 0.8 Co 0.15 Al 0.05 At least one of O2 and its modified compounds. Modified compounds refer to substances obtained by modification methods such as doping or coating based on the above-mentioned substances.

[0090] In some embodiments, the negative electrode may include a negative current collector.

[0091] As an example, the negative electrode current collector can be a metal foil, a conductive polymer material, a carbon material, or a composite current collector. For example, as a metal foil, pure metals, alloys, or surface-treated metals can be used, including but not limited to stainless steel, copper, aluminum, nickel, nickel alloys, titanium, or silver. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0092] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode film layer disposed on at least one surface of the negative electrode current collector.

[0093] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode film layer is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0094] As an example, the negative electrode film layer includes a negative electrode active material, which may be a negative electrode active material known in the art for use in battery cells. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as negative electrode active materials in battery cells may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0095] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0096] In some embodiments, the electrode assembly further includes a solid electrolyte. The solid electrolyte is disposed between the positive and negative electrode plates, serving both to transport ions and to isolate the positive and negative electrodes.

[0097] In some embodiments, the solid electrolyte includes a polymer solid electrolyte, an inorganic solid electrolyte, and a composite solid electrolyte.

[0098] As an example, the polymers of polymeric solid electrolytes may include polyethers (polyoxyethylene), polysiloxanes, polycarbonates, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymers, polyionic liquids, cellulose, etc.

[0099] As an example, inorganic solid electrolytes can be one or more of the following: oxide solid electrolytes (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON thin film), sulfide solid electrolytes (crystalline lithium superconducting ion conductor (lithium germanium phosphorus sulfide, silver sulfide germanium ore), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0100] As an example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to polymer solid electrolytes.

[0101] In some embodiments, the electrode assembly can be a wound structure, a stacked structure, or a hybrid structure of wound and stacked.

[0102] In some implementations, the electrode assembly is a wound structure. The positive and negative electrode sheets are wound into a wound structure.

[0103] In some implementations, the electrode assembly is a stacked structure.

[0104] As an example, multiple positive and negative electrode plates can be set, with multiple positive and multiple negative electrode plates stacked alternately. As an example, multiple positive electrode plates can be set, and negative electrode plates are folded to form multiple stacked folded segments, with a positive electrode plate sandwiched between adjacent folded segments.

[0105] As an example, both the positive and negative electrode plates are folded to form multiple stacked folded segments.

[0106] In some embodiments, the electrode assembly can be cylindrical, flat, or polygonal, etc.

[0107] In some embodiments, the positive current collector may include a positive tab, and the negative current collector may include a negative tab. The positive and negative tabs can be used to transmit current. As an example, at least a portion of the positive tab is not coated with a positive film layer, and at least a portion of the negative tab is not coated with a negative film layer.

[0108] In some embodiments, the electrode assembly is a wound structure. The positive electrode tab is wound multiple turns along the winding direction. Optionally, the end of the positive electrode tab is bent by a flattening or smoothing process to form a multi-layered structure stacked in the axial direction of the electrode assembly. Optionally, the positive electrode tab is annular.

[0109] In some embodiments, the negative electrode tab is wound multiple turns along the winding direction. Optionally, the end of the negative electrode tab is bent by a flattening or smoothing process to form a multi-layered structure stacked in the axial direction of the electrode assembly. The negative electrode tab is annular.

[0110] In some embodiments, the electrode assembly includes an electrode body. As an example, the electrode body includes a positive electrode film, a portion of a positive current collector covered by the positive electrode film, a negative electrode film, and a portion of a negative current collector covered by the negative electrode film.

[0111] The positive and negative tabs can be drawn from the same end of the electrode body, or they can be drawn from opposite ends of the electrode body.

[0112] In some embodiments, a battery cell includes a positive electrode lead and a negative electrode lead, wherein the positive electrode lead is electrically connected to a positive electrode plate and the negative electrode lead is electrically connected to a negative electrode plate.

[0113] The positive and negative leads are used to connect to the external circuit to enable charging or discharging of the battery cells.

[0114] In some embodiments, the positive lead-out portion includes a positive terminal. At least a portion of the positive terminal is exposed to the outside of the battery cell to facilitate connection with a busbar.

[0115] As an example, the positive terminal may be a separately molded component that is mounted on the housing. Alternatively, the positive terminal may also be part of the housing.

[0116] In some examples, the positive terminal is directly connected to the positive plate; in other examples, the positive terminal and the positive plate are indirectly connected through other conductive structures, such as a positive adapter.

[0117] In some embodiments, the positive terminal is attached to the end cap by welding, riveting, snap-fitting, or other means.

[0118] In some embodiments, the negative lead-out portion includes a negative terminal. At least a portion of the negative terminal is exposed to the outside of the battery cell to facilitate connection with a busbar.

[0119] As an example, the negative terminal can be a separately molded component that is mounted on the housing. Alternatively, the negative terminal can also be part of the housing.

[0120] In some examples, the negative terminal is directly connected to the negative electrode plate; in other examples, the negative lead-out section also includes other conductive structures connecting the negative terminal and the negative electrode plate, such as a negative adapter.

[0121] In some embodiments, the negative terminal is attached to the end cap by welding, riveting, snap-fitting, or other means.

[0122] Figure 5 This is a three-dimensional structural diagram of a battery cell provided in some embodiments of this application. Figure 6 This is a top view schematic diagram of a single battery cell provided in some embodiments of this application. Figure 7 for Figure 6A schematic diagram of the cross-sectional structure along AA. Figure 8 This is a top view of the first wall of a battery cell provided in some embodiments of this application. Figure 9 A first wall edge of a battery cell provided in some embodiments of this application Figure 8 The diagram shows a cross-sectional structure of BB.

[0123] Continue to refer to Figure 5 to Figure 9 This application provides a battery cell 7, which includes a housing 10, an electrolyte 20, a pressure relief mechanism 30, and an atomizing component 40. The housing 10 has a receiving cavity 11, in which the electrolyte 20 is contained. The pressure relief mechanism 30 is disposed on the housing 10. The atomizing component 40 is contained in the receiving cavity 11 and connected to the housing 10. The atomizing component 40 is configured to atomize the electrolyte 20 and spray it toward the pressure relief mechanism 30 when the battery cell 7 reaches a preset state.

[0124] The pressure relief mechanism 30 is used to release the internal gas of the battery cell 7.

[0125] As an example, the internal pressure or temperature of the battery cell 7 is actuated to release the internal pressure or temperature when it reaches a predetermined threshold. When the internal pressure or temperature of the battery cell 7 reaches the predetermined threshold, the pressure relief mechanism 30 is activated or a weak structure in the pressure relief mechanism 30 is destroyed, thereby forming an outlet or channel for the internal pressure or temperature to be released. The threshold design varies depending on the design requirements. The threshold may depend on the materials of one or more of the positive electrode, negative electrode, electrolyte, and separator in the battery cell 7.

[0126] As an example, the pressure relief mechanism 30 can be integrally formed with the housing 10.

[0127] As an example, the pressure relief mechanism 30 can also be separately configured and connected to the housing 10.

[0128] The term "actuation" as used in this application refers to the pressure relief mechanism 30 being activated or undergoing a certain state, thereby releasing the internal pressure and temperature of the battery cell 7. The actions of the pressure relief mechanism 30 may include, but are not limited to: movement of components within the pressure relief mechanism 30 to form an exhaust channel, rupture, breakage, tearing, or opening of at least a portion of the pressure relief mechanism 30, etc. When the pressure relief mechanism 30 is actuated, the high-temperature, high-pressure substances inside the battery cell 7 are discharged outwards from the actuated portion as exhaust materials. This method enables pressure and temperature relief of the battery cell 7 under controllable pressure or temperature conditions, thereby preventing potentially more serious accidents.

[0129] In some embodiments, when the housing 10 is a non-sealed structure, the pressure relief mechanism 30 can be configured as a through hole 531 for discharging gas inside the battery cell 7.

[0130] The emissions from the battery cell 7 mentioned in this application include, but are not limited to: electrolyte 20, dissolved or split positive and negative electrode plates, fragments of separators, high-temperature and high-pressure gases generated by the reaction, flames, etc.

[0131] The atomizing component 40 can be directly connected to the housing 10, or it can be constrained to the housing 10 by other components. As an example, the connection method between the atomizing component 40 and the housing 10 can be, but is not limited to, welding, bolting, plugging, or bonding.

[0132] For example, when the battery cell 7 is working normally, the atomizing component 40 may or may not be in contact with the electrolyte 20; when the battery cell 7 experiences thermal runaway, the temperature and pressure inside the battery cell 7 will rise sharply, the liquid level of the electrolyte 20 will rise, and the atomizing component 40 will come into contact with the electrolyte 20.

[0133] In this embodiment, the preset state refers to the critical condition for the atomizing component 40 to start. This preset state can be set to various conditions according to different needs. For example, the preset state may refer to the pressure inside the battery cell 7 rising to a certain threshold, or the temperature inside the battery cell 7 rising to a certain threshold, or the electrolyte level 20 inside the battery cell 7 being at a certain height and maintained for a certain time, and so on.

[0134] In this embodiment, the atomizing component 40 can atomize the electrolyte 20 in a "passive manner," that is, the atomizing component 40 drives the atomization process by utilizing the high temperature and high pressure environment generated when the battery cell 7 undergoes thermal runaway.

[0135] As an example, the atomizing component 40 may include a capillary structure that draws in the electrolyte 20 through capillary action. Under the high temperature and high pressure environment generated when the battery cell 7 experiences thermal runaway, the electrolyte 20 located in the capillary structure can be rapidly evaporated, atomized, and released.

[0136] The entire process of the atomizing component 40 atomizing the electrolyte 20 in a "passive manner" is driven by the high temperature and high pressure generated when the battery cell 7 undergoes thermal runaway. No sensors, circuits or external intervention are required, which helps to reduce the overall structural complexity of the battery cell 7, increase the energy density of the battery cell 7, and reduce costs.

[0137] In this embodiment of the application, the atomizing component 40 can also atomize the electrolyte 20 in an "active manner", that is, the atomizing component 40 itself has active energy input capability and can heat or pressurize the electrolyte 20 to atomize it.

[0138] As an example, the atomizing component 40 may include an atomizer and a sensor. The sensor is connected to the atomizer and is used to detect the temperature or pressure inside the receiving cavity 11. When the temperature inside the receiving cavity 11 reaches a first threshold or the pressure reaches a second threshold, the sensor sends a signal to the atomizer to start the atomizer from operating. The atomizer may be, but is not limited to, a resistance heating atomizer or a piezoelectric ultrasonic atomizer.

[0139] The entire process of atomizing the electrolyte 20 by the atomizing component 40 in an "active manner" is driven by the corresponding device of the atomizing component 40 itself, resulting in relatively higher response speed and accuracy.

[0140] When thermal runaway occurs in the battery cell 7, the temperature, pressure, and electrolyte level 20 inside the battery cell 7 will rise sharply. When the battery cell 7 reaches a preset state, the atomizing component 40 can atomize the electrolyte 20 and spray it towards the pressure relief mechanism 30. The atomized electrolyte 20 has a very large specific surface area, which can instantly absorb heat from the surrounding environment (especially the high-temperature area near the pressure relief mechanism 30) and evaporate violently. The evaporation process absorbs a large amount of heat, which will generate a strong local cooling effect, thereby effectively reducing the risk of combustion and improving the reliability of the battery cell 7.

[0141] In addition, in the safety test of battery cell 7, the embodiments of this application can significantly improve the pass rate of the safety test.

[0142] In some embodiments, the atomizing component 40 is configured to atomize the electrolyte 20 and spray it toward the pressure relief mechanism 30 when the pressure in the receiving cavity 11 reaches a first threshold.

[0143] As an example, the second threshold can be between 1 kPa and 5 kPa. For instance, the second threshold can be, but is not limited to, 1 kPa, 2 kPa, 3 kPa, 4 kPa, 5 kPa, etc.

[0144] In some embodiments, the atomizing component 40 is configured to atomize the electrolyte 20 and spray it toward the pressure relief mechanism 30 when the temperature within the containment cavity 11 reaches a second threshold.

[0145] As an example, the second threshold can be 100℃-150℃. For example, the second threshold can be, but is not limited to, 100℃, 110℃, 120℃, 130℃, 140℃, 150℃, etc.

[0146] The changes in temperature and pressure can directly reflect the evolution of the internal thermal state of the battery cell 7. Furthermore, by triggering the atomization mechanism through temperature and / or pressure, it is easy to achieve passive triggering of the atomization component 40, which can achieve a simpler structural design and help reduce costs.

[0147] Furthermore, temperature and pressure signals are easy to acquire, exhibit clear trends, and are not easily affected by short-term vibrations or mechanical stress. Therefore, by triggering the atomization mechanism through temperature and / or pressure, more precise control can be achieved under the active triggering scheme of the atomizing component 40, thereby improving the reliability of the atomizing component 40.

[0148] In some embodiments, the atomizing component 40 is disposed on the side of the pressure relief mechanism 30 facing the receiving cavity 11.

[0149] During the process of thermal runaway of battery cell 7 and electrolyte 20 being ejected from pressure relief mechanism 30, atomizing component 40 can be positioned in the spray path of electrolyte 20, enabling atomizing component 40 to atomize electrolyte 20 more quickly at the critical moment when thermal runaway of battery cell 7 occurs, achieving rapid intervention cooling, thereby effectively improving the response speed of atomizing component 40.

[0150] In some embodiments, the housing 10 includes a first wall 12 disposed on one side of the receiving cavity 11 along the first direction X, and the pressure relief mechanism 30 is disposed on the first wall 12. In the same plane perpendicular to the first direction X, the orthographic projection of the atomizing component 40 and the orthographic projection of the pressure relief mechanism 30 at least partially overlap.

[0151] For example, in the same plane perpendicular to the first direction X, the orthographic projection of the atomizing component 40 may partially overlap with the orthographic projection of the pressure relief mechanism 30, or the orthographic projection of the atomizing component 40 may overlap with the orthographic projection of the pressure relief mechanism 30.

[0152] In some embodiments, the housing 10 includes a first wall 12 disposed on one side of the receiving cavity 11 along a first direction X, and a pressure relief mechanism 30 disposed on the first wall 12. The battery cell 7 also includes a collecting component 50 connected to the side of the first wall 12 facing the receiving cavity 11. The collecting component 50 has a cavity 51, and an opening 52 is provided on the side of the collecting component 50 facing the first wall 12, communicating with the cavity 51. In the same plane perpendicular to the first direction X, the orthographic projection of the pressure relief mechanism 30 at least partially overlaps with the orthographic projection of the opening 52. The collecting component 50 includes a side wall 53 surrounding the opening 52, and a through hole 531 is provided on the side wall 53, communicating with the cavity 51 and the receiving cavity 11. At least a portion of the atomizing component 40 is disposed within the cavity 51.

[0153] The collecting component 50 is used to collect the electrolyte 20. For example, before the battery cell 7 experiences thermal runaway, there is a period of time during which the temperature and pressure inside the containment cavity 11 rise. Under the action of high temperature and high pressure, the electrolyte 20 will move. During this process, a portion of the electrolyte 20 will enter the cavity 51 of the collecting component 50 and be collected, thereby providing enough electrolyte 20 for the subsequent atomizing component 40 to atomize. The atomizing component 40 can spray the atomized electrolyte 20 towards the pressure relief component through the opening 52.

[0154] In the same plane perpendicular to the first direction X, the orthographic projection of the pressure relief mechanism 30 may partially overlap with the orthographic projection of the opening 52, or the orthographic projection of the pressure relief mechanism 30 may overlap with the orthographic projection of the opening 52.

[0155] The assembly component 50 can be directly connected to the first wall 12, or it can be constrained to the first wall 12 by other components. As an example, the connection method between the assembly component 50 and the first wall 12 can be, but is not limited to, welding, bolting, plugging, or bonding.

[0156] The atomizing component 40 may be partially disposed inside the cavity 51 and partially disposed outside the collecting component 50, or the atomizing component 40 may be entirely disposed inside the cavity 51.

[0157] Optionally, the projection shape of the opening 52 along the first direction X can be, but is not limited to, a circle, a rectangle, or an ellipse.

[0158] The above technical solution introduces a collecting component 50, which can collect more electrolyte 20 to the working area of ​​the atomizing component 40, thereby increasing the atomization amount of the atomizing component 40 when the battery cell 7 experiences thermal runaway, thus further reducing the combustion risk of the battery cell 7 during thermal runaway and improving the reliability of the battery cell 7.

[0159] In some embodiments, the atomizing components 40 are all disposed within the cavity 51.

[0160] In some embodiments, in the same plane perpendicular to the first direction X, the orthographic projection of the atomizing component 40 and the orthographic projection of the opening 52 at least partially overlap.

[0161] This allows the fine droplets formed by the atomizing component 40 to be sprayed onto the opening 52 along a shorter path and with less deviation. This significantly improves the spray concentration of the atomizing component 40 and reduces the lateral diffusion of droplets within the cavity 51, thereby further improving the cooling effect of the atomizing component 40 on the pressure relief mechanism 30 during thermal runaway of the battery cell 7.

[0162] For example, in the same plane perpendicular to the first direction X, the orthographic projection of the atomizing component 40 may partially overlap with the orthographic projection of the opening 52, or the orthographic projection of the atomizing component 40 may overlap with the orthographic projection of the opening 52.

[0163] In some embodiments, the atomizing component 40, the opening 52, and the pressure relief mechanism 30 are arranged along a first direction X.

[0164] In some embodiments, the first direction X is parallel to the direction of gravity.

[0165] In some embodiments, the first wall 12 is located on the side of the receiving cavity 11 in the direction opposite to the direction of gravity.

[0166] In some embodiments, the atomizing component 40 is disposed at the end of the collecting component 50 away from the pressure relief mechanism 30, which can reduce the risk of impact damage to the atomizing component 40 during the opening of the pressure relief mechanism 30.

[0167] In addition, when the first wall 12 is located on the side of the receiving cavity 11 in the opposite direction to the direction of gravity, due to gravity, the electrolyte 20 in the cavity 51 will naturally gather at the end away from the pressure relief mechanism 30, that is, the location of the atomizing component 40, so that the atomizing component 40 can obtain sufficient electrolyte 20 and complete the atomization work in the first time, so as to further improve the cooling effect of the atomizing component 40 on the pressure relief mechanism 30 when the battery cell 7 thermally runs away.

[0168] In some embodiments, the side surface of the sidewall 53 facing the cavity 51 is a tapered surface that gradually tapers away from the pressure relief mechanism 30.

[0169] For example, the conical surface can be a circular cone or a pyramidal surface.

[0170] The conical surface can guide the mist sprayed by the atomizing component 40 to diffuse in the direction toward the opening 52, so that it can form a high-density mist band when it reaches the opening 52, thereby forming a larger cooling coverage area at the location of the pressure relief mechanism 30, so as to further reduce the risk of combustion when the battery cell 7 undergoes thermal runaway.

[0171] In addition, when the first wall 12 is located on the side of the receiving cavity 11 in the direction opposite to the direction of gravity, the conical surface, as a guiding slope, can further improve the effect of the electrolyte 20 converging towards the bottom of the cavity 51, i.e., the area where the atomizing component 40 is located, during the flow process.

[0172] In some embodiments, the side surface of the sidewall 53 facing the cavity 51 is a conical surface that gradually tapers away from the pressure relief mechanism 30.

[0173] Figure 10The first wall edge of another battery cell provided in some embodiments of this application Figure 8 The diagram shows a cross-sectional structure of BB.

[0174] Continue to refer to Figure 10 In some embodiments, the collecting component 50 further includes a bottom wall 54 located on the side of the cavity 51 opposite to the opening 52, the bottom wall 54 being connected to the side wall 53, and the atomizing component 40 being connected to the bottom wall 54.

[0175] The above technical solution further introduces a bottom wall 54, which can provide a stable installation foundation for the atomizing component 40. This not only reduces the installation difficulty of the atomizing component 40, but also improves the structural stability of the atomizing component 40.

[0176] In some embodiments, the bottom wall 54 and the side wall 53 are integrally formed structures.

[0177] On the one hand, the manufacturing process is simplified because there is no need to connect the bottom wall 54 and the side wall 53 through an additional connection process. On the other hand, compared with connecting the bottom wall 54 and the side wall 53 through an additional connection process, the bottom wall 54 and the side wall 53, which are integrated, have higher structural strength.

[0178] Figure 11 The first wall edge of another battery cell provided in some embodiments of this application Figure 8 The diagram shows a cross-sectional structure of BB.

[0179] Continue to refer to Figure 11 In some embodiments, the battery cell 7 further includes a drain tube 60, one end of which is connected to the collecting component 50 and communicates with the cavity 51, and the other end of which is further away from the first wall 12 in the first direction X relative to the collecting component 50.

[0180] For example, the drainage tube 60 has a capillary channel inside, with a first opening and a second opening at both ends of the drainage tube 60. The capillary channel is connected to the cavity 51 through the first opening and to the receiving cavity 11 through the second opening. The electrolyte 20 can enter the capillary channel through the second opening and then enter the cavity 51 through the first opening.

[0181] In the early stage of thermal runaway of battery cell 7, the internal temperature of battery cell 7 rises rapidly. Electrolyte 20 can be collected more quickly into cavity 51 through drainage tube 60, which can provide timely source of electrolyte 20 for atomizing component 40, thereby improving the response speed of atomizing component 40.

[0182] In some embodiments, one end of the drainage tube 60 is connected to the side wall 53.

[0183] In some embodiments, one end of the drainage tube 60 is connected to the bottom wall 54.

[0184] In some embodiments, the end of the drain tube 60 away from the collecting component 50 is inserted into the electrolyte 20. This can further improve the timeliness of the electrolyte 20 entering the cavity 51 and further improve the response speed of the atomizing component 40.

[0185] Figure 12 For some embodiments of this application, another type of battery cell with a first wall edge Figure 8 The diagram shows a cross-sectional structure of BB.

[0186] Continue to refer to Figure 12 In some embodiments, the battery cell 7 further includes a sealing component 70 connected to the collecting component 50 and closing the opening 52. The sealing component 70 is configured to break when the battery cell 7 reaches a preset state to connect the cavity 51 and the pressure relief mechanism 30.

[0187] Under normal operating conditions of the battery cell 7, the sealing component 70 closes the opening 52, isolating the atomizing component 40 from the internal environment of the battery cell 7, thereby reducing the risk of failure of the atomizing component 40 due to the influence of the internal environment of the battery cell 7. When the battery cell 7 reaches a preset state, such as thermal runaway, the sealing component 70 will break, exposing the opening 52 to connect the cavity 51 and the pressure relief mechanism 30, providing conditions for the atomizing component 40 to spray liquid mist into the pressure relief mechanism 30.

[0188] As an example, the sealing component 70 is configured to break when the pressure within the receiving cavity 11 reaches a first threshold to connect the cavity 51 and the pressure relief mechanism 30.

[0189] For example, when the battery cell 7 experiences thermal runaway, the pressure inside the containment cavity 11 will rise rapidly. When the pressure inside the containment cavity 11 reaches a first threshold, the pressure can cause the sealing component 70 to rupture or brittlely disintegrate. The damaged sealing component 70 exposes the opening 52, allowing the atomizing component 40 to spray liquid mist into the pressure relief mechanism 30 through the opening 52.

[0190] As another example, the sealing component 70 is configured to break when the temperature within the receiving cavity 11 reaches a certain threshold to connect the cavity 51 and the pressure relief mechanism 30.

[0191] For example, when the battery cell 7 experiences thermal runaway, the temperature inside the containment cavity 11 rises rapidly. When the temperature inside the containment cavity 11 reaches a first threshold, the temperature is sufficient to cause the sealing component 70 to melt, rupture, or brittlely disintegrate. The damaged sealing component 70 exposes the opening 52, allowing the atomizing component 40 to spray atomized liquid into the pressure relief mechanism 30 through the opening 52.

[0192] Optionally, the sealing component 70 may be made of a thermally responsive material, such as a low-melting-point material or a thin sheet of polymer material with brittle fracture properties.

[0193] Optionally, the sealing component 70 may be, but is not limited to, a plate-like structure, a block-like structure, or a membrane-like structure.

[0194] In some embodiments, there are multiple atomizing components 40, and at least a portion of the multiple atomizing components 40 are arranged along the outer contour of the pressure relief mechanism 30.

[0195] In other words, when the pressure relief mechanism 30 is provided on the first wall 12, at least a portion of the atomizing components 40 are arranged along the outer periphery of the orthogonal projection of the pressure relief mechanism 30 in the same plane perpendicular to the first direction X.

[0196] In the embodiments of this application, "multiple" refers to two or more.

[0197] Multiple atomizing components 40 arranged along the outer contour of the pressure relief mechanism 30 can spray the pressure relief mechanism 30 from different directions to increase the overall droplet coverage and further improve the cooling effect of the atomizing components 40 on the pressure relief mechanism 30 in the event of thermal runaway of the battery cell 7. In addition, the spraying of multiple atomizing components 40 can form a droplet overlap area, which can further improve the local cooling effect.

[0198] In some embodiments, the number of atomizing components 40 is multiple, and at least a portion of the atomizing components 40 are spaced apart along the outer contour of the pressure relief mechanism 30.

[0199] In some embodiments, a plurality of atomizing components 40 are spaced apart along a direction intersecting the first direction X.

[0200] In some embodiments, a plurality of atomizing components 40 are spaced apart along a direction perpendicular to the first direction X.

[0201] In some embodiments, a plurality of atomizing components 40 are arranged in an array along a direction intersecting the first direction X.

[0202] In some embodiments, a plurality of atomizing components 40 are arranged in an array along a direction perpendicular to the first direction X.

[0203] In some embodiments, the assembly component 50 and the first wall 12 are integrally formed.

[0204] On the one hand, the assembly component 50 and the first wall 12 do not require additional connection processes, simplifying the manufacturing process. On the other hand, compared to connecting the assembly component 50 and the first wall 12 through additional connection processes, the integrated structure of the assembly component 50 and the first wall 12 provides higher structural strength.

[0205] In some embodiments, the housing 10 includes an end cap and a housing having a receiving cavity 11 and an opening 52 communicating with the receiving cavity 11, the end cap closing onto the opening 52, and the end cap being configured as a first wall 12.

[0206] According to some embodiments of this application, this application also provides a battery device including a battery cell 7 of any of the above schemes.

[0207] According to some embodiments of this application, this application provides an electrical device for an energy storage device, which includes multiple battery cells or multiple battery devices provided by any of the above schemes, wherein the battery cells or battery devices are used to store or provide electrical energy.

[0208] According to some embodiments of this application, this application provides an energy storage system, which includes an energy conversion system and an energy storage device provided by any of the above schemes. The energy conversion system is connected to the energy storage device to convert the current input to the energy storage device or output from the energy storage device into energy.

[0209] According to some embodiments of this application, this application provides a charging network, which includes a charging pile and an energy storage device or an energy storage system provided by any of the above solutions, wherein the energy storage device is used to provide electrical energy to the charging pile.

[0210] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions. All technical features and optional technical features of this application can be combined to form new technical solutions.

[0211] To better understand the battery cell 7 provided in the embodiments of this application, based on the same inventive concept, an embodiment of the battery cell 7 in practical application is provided here for illustration.

[0212] This application provides a battery cell 7, which includes a housing 10, an electrolyte 20, a pressure relief mechanism 30, an atomizing component 40, a collecting component 50, and a sealing component 70. The housing 10 has a receiving cavity 11, in which the electrolyte 20 is contained. The pressure relief mechanism 30 is disposed on the housing 10. The housing 10 includes a first wall 12, which is disposed on one side of the receiving cavity 11 along a first direction X. The pressure relief mechanism 30 is disposed on the first wall 12.

[0213] The atomizing component 40 is housed within the receiving cavity 11 and connected to the outer casing 10. The atomizing component 40 is disposed on the side of the pressure relief mechanism 30 facing the receiving cavity 11. The atomizing component 40 is configured to atomize the electrolyte 20 and spray it toward the pressure relief mechanism 30 when the pressure within the receiving cavity 11 reaches a first threshold, and / or, the atomizing component 40 is configured to atomize the electrolyte 20 and spray it toward the pressure relief mechanism 30 when the temperature within the receiving cavity 11 reaches a second threshold.

[0214] A collecting component 50 is connected to the side of the first wall 12 facing the receiving cavity 11. The collecting component 50 has a cavity 51, and an opening 52 is provided on the side of the collecting component 50 facing the first wall 12, the opening 52 communicating with the cavity 51. In the same plane perpendicular to the first direction X, the orthographic projection of the pressure relief mechanism 30 at least partially overlaps with the orthographic projection of the opening 52. The collecting component 50 includes a side wall 53, which surrounds the opening 52. A through hole 531 is provided on the side wall 53, communicating with the cavity 51 and the receiving cavity 11. At least a portion of the atomizing component 40 is disposed within the cavity 51. In the same plane perpendicular to the first direction X, the orthographic projection of the atomizing component 40 at least partially overlaps with the orthographic projection of the opening 52. The atomizing component 40 is disposed at the end of the collecting component 50 away from the pressure relief mechanism 30, and the surface of the side wall 53 facing the cavity 51 is a tapered surface that gradually tapers away from the pressure relief mechanism 30.

[0215] The sealing component 70 is connected to the collecting component 50 and closes the opening 52. The sealing component 70 is configured to break when the pressure in the receiving cavity 11 reaches a first threshold to connect the cavity 51 and the pressure relief mechanism 30, and / or, the sealing component 70 is configured to break when the temperature in the receiving cavity 11 reaches a second threshold to connect the cavity 51 and the pressure relief mechanism 30.

[0216] When thermal runaway occurs in the battery cell 7, the temperature, pressure, and electrolyte level 20 inside the battery cell 7 will rise sharply. When the battery cell 7 reaches a preset state, the atomizing component 40 can atomize the electrolyte 20 and spray it towards the pressure relief mechanism 30. The atomized electrolyte 20 has a very large specific surface area, which can instantly absorb heat from the surrounding environment (especially the high-temperature area near the pressure relief mechanism 30) and evaporate violently. The evaporation process absorbs a large amount of heat, which will generate a strong local cooling effect, thereby effectively reducing the risk of combustion and improving the reliability of the battery cell 7.

[0217] In addition, in the safety test of battery cell 7, the embodiments of this application can significantly improve the pass rate of the safety test.

[0218] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0219] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized in that, include: The housing has a receiving cavity, the housing including a first wall disposed on one side of the receiving cavity along a first direction; Electrolyte is contained within the containment cavity; A pressure relief mechanism is installed on the first wall; A collecting component is connected to the side of the first wall facing the receiving cavity. The collecting component has a cavity and an opening on the side of the collecting component facing the first wall, the opening communicating with the cavity. In the same plane perpendicular to the first direction, the orthographic projection of the pressure relief mechanism and the orthographic projection of the opening at least partially overlap. The collecting component includes a sidewall surrounding the opening and a through hole on the sidewall communicating with the cavity and the receiving cavity. An atomizing component, at least a portion of which is disposed within the cavity, is configured to atomize the electrolyte and spray it toward the pressure relief mechanism when the battery cell reaches a preset state.

2. The battery cell according to claim 1, characterized in that, The atomizing component is configured to atomize the electrolyte and spray it toward the pressure relief mechanism when the pressure within the receiving cavity reaches a first threshold; and / or The atomizing component is configured to atomize the electrolyte and spray it toward the pressure relief mechanism when the temperature within the containment cavity reaches a second threshold.

3. The battery cell according to claim 1, characterized in that, The atomizing component is located on the side of the pressure relief mechanism facing the receiving cavity.

4. The battery cell according to claim 1, characterized in that, In the same plane perpendicular to the first direction, the orthographic projection of the atomizing component at least partially overlaps with the orthographic projection of the opening.

5. The battery cell according to claim 1, characterized in that, The atomizing component is located at the end of the collecting component away from the pressure relief mechanism.

6. The battery cell according to claim 5, characterized in that, The sidewall facing the cavity is a tapered surface that gradually tapers away from the pressure relief mechanism.

7. The battery cell according to claim 1, characterized in that, The collecting component also includes a bottom wall located on the side of the cavity opposite to the opening, the bottom wall being connected to the side wall, and the atomizing component being connected to the bottom wall.

8. The battery cell according to claim 1, characterized in that, The battery cell also includes a drain tube, one end of which is connected to the collecting component and communicates with the cavity, and the other end of which is further away from the first wall in the first direction relative to the collecting component.

9. The battery cell according to claim 8, characterized in that, The end of the drain tube furthest from the collecting component is inserted into the electrolyte.

10. The battery cell according to claim 1, characterized in that, The battery cell also includes a sealing component, which is connected to the collecting component and closes the opening; The sealing component is configured to break when the battery cell reaches the preset state to connect the cavity and the pressure relief mechanism.

11. The battery cell according to claim 1, characterized in that, The number of atomizing components is multiple, and at least a portion of the multiple atomizing components are arranged along the outer contour of the pressure relief mechanism.

12. A battery device, characterized in that, It includes multiple battery cells as described in any one of claims 1-11.

13. An energy storage device, characterized in that, It includes a plurality of battery cells as described in any one of claims 1-11 or a plurality of battery devices as described in claim 12, wherein the battery cells or the battery devices are used to store or provide electrical energy.

14. An energy storage system, characterized in that, It includes an energy conversion system and an energy storage device as described in claim 13, wherein the energy conversion system is connected to the energy storage device to convert the current input to or output from the energy storage device into energy.

15. A charging network, characterized in that, It includes a charging pile and an energy storage device as described in claim 13 or an energy storage system as described in claim 14, wherein the energy storage device is used to provide electrical energy to the charging pile.

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