Battery monomer, battery device and electric equipment

Abstract

The utility model relates to a battery monomer, a battery device and electric equipment, and belongs to the technical field of batteries. The battery monomer comprises a shell and a fire extinguishing medium, the shell comprises an end cover assembly and a shell body, the end cover assembly and the shell body jointly define a containing space, and the end cover assembly is provided with a cavity communicated with the containing space; the fire extinguishing medium is arranged in the containing space and / or the cavity. According to the battery monomer, the battery device and the electric equipment provided by the invention, rapid response is realized at the initial stage of thermal runaway of the battery monomer, the risk that the thermal runaway of the single battery monomer spreads to the adjacent battery monomer is reduced, and the reliability of the battery monomer is improved.

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] With the development of new energy, more and more fields are adopting new energy as a power source. Due to its advantages such as high energy density, rechargeable, safe and environmentally friendly, power batteries are widely used in new energy vehicles, consumer electronics, energy storage systems and other fields.

[0003] In the development of battery cell technology, in addition to improving the performance of battery cells, the reliability of battery cells is also an issue that needs to be considered. Therefore, how to improve the reliability of battery cells is an issue that needs to be continuously improved in battery device technology. Utility Model Content

[0004] In view of the above problems, the present application provides a battery cell, a battery device and an electrical equipment, which can respond quickly in the early stage of thermal runaway of the battery cell, reduce the risk of thermal runaway of a single battery cell spreading to adjacent battery cells, and have higher reliability.

[0005] In a first aspect, an embodiment of the present application provides a battery cell, which includes an outer shell and a fire extinguishing medium, wherein the outer shell includes an end cover assembly and a shell, the end cover assembly and the shell together form a receiving space, and the end cover assembly is provided with a cavity connected to the receiving space; the fire extinguishing medium is provided in the receiving space and / or the cavity.

[0006] In the technical solution of the embodiment of the present application, by arranging the fire extinguishing medium in the containing space and / or cavity, the fire extinguishing medium can quickly sense the temperature change in the early stage of the fire, thereby improving the fire response sensitivity of the fire extinguishing medium; at the same time, such an arrangement enables the fire extinguishing medium to act directly in the containing space, realize active fire extinguishing in the early stage of the fire, reduce the risk of thermal runaway of a single battery cell spreading to adjacent battery cells, and improve reliability.

[0007] In some embodiments, the fire extinguishing medium is connected to the end cap assembly, with at least a portion of the fire extinguishing medium protruding from the surface of the end cap assembly near the receiving space. This design directly positions at least a portion of the fire extinguishing medium within the receiving space, further reducing the fire extinguishing medium's response speed to a fire and facilitating its direct action at the fire's location, thereby reducing the risk of large-scale fires in battery cells due to thermal runaway.

[0008] In some embodiments, the fire extinguishing medium is disposed within the cavity. This allows the fire extinguishing medium to be separated from other components within the storage space, reducing its impact on the normal operation of the battery cells when no fire occurs and allowing for rapid response and extinguishing of fires when they occur.

[0009] In some embodiments, the end cap assembly includes a stacked insulating member and an end cap, the insulating member being located on a side of the end cap proximal to the receiving space, and the cavity being disposed within the insulating member. The end cap assembly includes a stacked insulating member and an end cap, and the materials of the insulating member and the end cap can be designed to meet the insulation and sealing requirements of the battery cell.

[0010] In some embodiments, the end cap is equipped with a pressure relief mechanism, with the cavity and the pressure relief mechanism positioned opposite each other along the stacking direction of the insulating member and the end cap. This arrangement fully utilizes the space on the side of the pressure relief mechanism closest to the receiving space, eliminating the need for additional space on the end cap assembly for the fire extinguishing medium, thereby improving battery cell production efficiency.

[0011] In some embodiments, the cavity is formed by bending from the insulating member away from the end cap, and a communication channel is provided between the cavity and the accommodating space, with the communication channel being provided in the bottom wall and / or side wall of the cavity. By configuring the cavity to be formed by bending from the insulating member away from the end cap, the gap between the electrode assembly and the end cap assembly can be fully utilized, expanding the design space of the cavity, thereby allowing for the storage of a larger dose of fire extinguishing medium, thereby improving the fire extinguishing effect.

[0012] In some embodiments, the communication channel is provided on the bottom wall of the cavity and includes a plurality of through-grooves spaced apart in sequence; at least some of the through-grooves connect the cavity with the receiving space in a direction intersecting the thickness of the bottom wall of the cavity. By providing the communication channel with a plurality of through-grooves, with at least some of the through-grooves connecting the cavity with the receiving space in a direction intersecting the thickness of the bottom wall of the cavity, i.e., by providing at least some of the through-grooves as an obliquely disposed groove structure, heat from various locations in the receiving space is facilitated from diffusing into the cavity, further enhancing the responsiveness of the fire extinguishing medium. Furthermore, the uniformity with which the fire extinguishing medium diffuses into the receiving space after being activated is also enhanced, further improving the fire extinguishing coverage and reliability of the fire extinguishing medium.

[0013] In some embodiments, the insulation is made of polyphenylene sulfide sheet material or a composite sheet material of polypropylene and glass fiber. This configuration ensures that the insulation has excellent heat resistance and is not easily deformed in the event of a fire, allowing the fire extinguishing medium to be accurately applied to the containment space after being activated. Furthermore, the more heat-resistant insulation material helps to trap heat within the battery cell experiencing thermal runaway, slowing the rate of heat radiation to other battery cells and improving reliability.

[0014] In some embodiments, the fire extinguishing medium is bonded to the end cap assembly. This design helps improve the structural stability of the fire extinguishing medium, reduces the risk of the fire extinguishing medium being displaced from its designed position when bumped, bumped, or dropped, and helps improve the stability of fire extinguishing through the fire extinguishing medium.

[0015] In some embodiments, the fire extinguishing medium is a perfluorohexanone sheet, a heptafluoropropane sheet, a perfluoro(2-methyl-3-pentanone) sheet, or an ammonium polyphosphate sheet. This allows the fire extinguishing medium to enhance the flame retardancy of the battery cells after being activated, further improving the reliability of the battery cells in the event of thermal runaway.

[0016] In a second aspect, an embodiment of the present application further provides a battery device, which includes a battery cell provided in any of the aforementioned embodiments.

[0017] In a third aspect, an embodiment of the present application further provides an electrical device, which includes a battery device as provided in any of the aforementioned embodiments, and the battery device is used to provide electrical energy.

[0018] 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

[0019] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 A schematic structural diagram of a vehicle provided in one embodiment of the present application;

[0021] Figure 2 A schematic diagram of the three-dimensional structure of a battery device provided in one embodiment of the present application;

[0022] Figure 3 A schematic diagram of the exploded three-dimensional structure of a battery cell provided in one embodiment of the present application;

[0023] Figure 4 A schematic diagram of the exploded three-dimensional structure of an end cap assembly in a battery cell according to an embodiment of the present application;

[0024] Figure 5 A schematic diagram of the exploded three-dimensional structure of an end cap assembly in a battery cell provided in another embodiment of the present application;

[0025] Figure 6 A cross-sectional view of an insulating member in a battery cell provided in one embodiment of the present application;

[0026] Figure 7 for Figure 6 An enlarged view of part A of the battery cell is shown.

[0027] Description of reference numerals: 1, vehicle; 2000, controller; 3000, motor; 1000, battery device; 200, housing; 201, first part; 202, second part;

[0028] 100, battery cell; 10, housing; 11, end cap assembly; 111, insulation; 1111, pressure relief mechanism; 112, end cap; 12, housing; 13, electrode assembly; 20, fire extinguishing medium;

[0029] 101. Accommodation space; 102. Cavity; 103. Communication channel; 1031. Through groove. DETAILED DESCRIPTION

[0030] To make the above-mentioned objects, features, and advantages of the present application more clearly understood, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0031] In the description of this application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0032] In addition, if the term "and / or" appears, "and / or" is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent three situations: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the objects associated with each other are in an "or" relationship. If the terms "first" and "second" appear, these terms are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "multiple" appears, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0033] In this application, unless otherwise specified or limited, the terms "mounted," "connected," "connected," "fixed," etc., should be interpreted broadly. For example, these terms may refer to fixed connections, removable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediary; and internal communication between two components or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0034] In this application, unless otherwise expressly specified or limited, if a first feature is described as being "above" or "below" a second feature, or similar descriptions, this may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is described as being "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is described as being "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0035] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only embodiment.

[0036] Compared to other battery types, such as lead-acid and nickel-cadmium batteries, lithium-ion batteries offer advantages such as high specific capacity, high operating voltage, fast charging, a wide operating temperature range, long cycle life, compact size, and light weight. They are widely used not only in portable electronic devices such as mobile phones, digital cameras, and laptops, but also in large and medium-sized electric devices such as electric vehicles, electric bicycles, and power tools. However, the safety of lithium batteries remains a key factor influencing their development.

[0037] The positive electrode materials of lithium-ion batteries generally include lithium-rich manganese-based materials, lithium cobalt oxide, lithium manganese oxide, lithium nickel cobalt manganese oxide, and lithium iron phosphate. The negative electrode is generally composed of graphite or silicon-carbon composite materials. During the charging process, lithium ions are released from the positive electrode material and embedded in the negative electrode material through the electrolyte and separator. When fully charged, the positive electrode of a lithium-ion battery is highly oxidizing, while the negative electrode is highly reducing. The electrolyte used is LiPF6, which decomposes easily when heated and is sensitive to water. The electrolyte solvent is generally an organic carbonate solvent with a low flash point. Under conditions such as overcharging, over-discharging, and overheating, the battery can cause thermal runaway, resulting in combustion or even explosion.

[0038] In order to improve the problem of combustion or even explosion caused by thermal runaway of batteries, relevant technologies usually adopt the method of embedding fire extinguishing medium in the plastic parts of the end cover assembly. When thermal runaway occurs in the battery cell or battery module, the plastic parts melt due to heat and release the fire extinguishing medium, thereby controlling the fire.

[0039] However, research has found that the flame retardant and fire extinguishing methods of related technologies cannot stop the fire in a timely manner. In other words, the fire extinguishing medium embedded in the end cap assembly cannot be released until the temperature rises to a level sufficient to melt the plastic parts of the end cap assembly, which has a certain lag in implementing flame retardant, fire extinguishing, and explosion-proof measures for battery cells experiencing thermal runaway. Furthermore, the melting point of the plastic parts of the end cap assembly of related technologies is generally between 160°C and 170°C. Once a battery cell experiences thermal runaway and the temperature reaches 160°C to 170°C, the difficulty of implementing fire extinguishing remedial measures increases significantly, and there is a risk of heat radiation spreading to other battery cells that have not experienced thermal runaway.

[0040] Based on the above considerations, the inventors conducted in-depth research and designed a battery cell, in which a fire extinguishing medium is set in the storage space and / or cavity of the battery cell. When the battery cell experiences thermal runaway, the fire extinguishing medium can respond to the fire in a timely manner and perform flame retardant, fire extinguishing and other control measures on the part of the battery cell where thermal runaway occurs, thereby reducing the risk of further spread of the fire and improving the reliability of the battery cell.

[0041] The battery cells disclosed in the embodiments of the present application can be used in, but are not limited to, electrical equipment such as vehicles, ships, or aircraft.

[0042] The present invention provides an electrical device that uses a battery device as a power source. The electrical device may include, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery-powered vehicle, an electric car, a ship, a spacecraft, and the like. The electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, and the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, and the like.

[0043] For the convenience of description, the following embodiments are described by taking a vehicle 1 as an example of an electrical device according to an embodiment of the present application.

[0044] Please refer to Figure 1 , Figure 1 A schematic structural diagram of a vehicle provided for one embodiment of the present application. Vehicle 1 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery device 1000 is provided inside the vehicle 1, and the battery device 1000 may be provided at the bottom, head or tail of the vehicle 1. The battery device 1000 may be used to power the vehicle 1, for example, the battery device 1000 may serve as an operating power source for the vehicle 1. The vehicle 1 may further include a controller 2000 and a motor 3000, and the controller 2000 is used to control the battery device 1000 to power the motor 3000, for example, for starting, navigating and operating power requirements of the vehicle 1 during driving.

[0045] In some embodiments of the present application, the battery device 1000 can serve not only as an operating power source for the vehicle 1 , but also as a driving power source for the vehicle 1 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1 .

[0046] Please refer to Figure 2 , Figure 2A schematic diagram of the three-dimensional structure of a battery device provided in one embodiment of the present application. The battery device 1000 includes a housing 200 and a battery cell 100, with the battery cell 100 being housed in the housing 200. The housing 200 is used to provide a storage space for the battery cell 100, and the housing 200 can adopt a variety of structures. In some embodiments, the housing 200 can include a first portion 201 and a second portion 202, the first portion 201 and the second portion 202 covering each other, and the first portion 201 and the second portion 202 jointly defining a storage space for accommodating the battery cell 100. The second portion 202 can be a hollow structure with one end open, and the first portion 201 can be a plate-like structure, with the first portion 201 covering the open side of the second portion 202, so that the first portion 201 and the second portion 202 jointly define a storage space; the first portion 201 and the second portion 202 can also be hollow structures with one side open, with the open side of the first portion 201 covering the open side of the second portion 202. Of course, the box body 200 formed by the first part 201 and the second part 202 can be in various shapes, such as a cylinder, a cuboid, etc.

[0047] In the battery device 1000, there may be multiple battery cells 100, and the multiple battery cells 100 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 100. The multiple battery cells 100 may be directly connected in series, in parallel, or in a hybrid connection, and then the entire battery unit formed by the multiple battery cells 100 may be housed within the housing 200. Of course, the battery device 1000 may also be a battery module formed by first connecting multiple battery cells 100 in series, in parallel, or in a hybrid connection, and then the multiple battery modules are further connected in series, in parallel, or in a hybrid connection to form an entire battery unit, which is then housed within the housing 200. The battery device 1000 may also include other structures, for example, the battery device 1000 may further include a busbar component for achieving electrical connection between the multiple battery cells 100.

[0048] Each battery cell 100 may be a secondary battery or a primary battery; it may also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 100 may be cylindrical, flat, rectangular, or in other shapes.

[0049] Please refer to Figure 3 , Figure 3 A schematic diagram of the three-dimensional structure of a battery cell provided in one embodiment of the present application. A battery cell 100 is the smallest unit that constitutes a battery. Figure 3 The battery cell 100 includes an end cap assembly 11, a shell 12, an electrode assembly 13 and other functional components.

[0050] The end cap assembly 11 is a component that covers the opening of the housing 12 to isolate the internal environment of the battery cell 100 from the external environment. The shape of the end cap assembly 11 can be adapted to the shape of the housing 12 to fit the housing 12. Optionally, the end cap assembly 11 can be made of a material with a certain hardness and strength (such as an aluminum alloy). This prevents the end cap assembly 11 from deforming when subjected to compression or collision, thereby providing the battery cell 100 with greater structural strength and improved safety. The end cap assembly 11 can be provided with functional components such as electrode terminals. The electrode terminals can be used to electrically connect to the electrode assembly 13 for outputting or inputting electrical energy into or out of the battery cell 100. In some embodiments, the end cap assembly 11 can also be provided with a pressure relief mechanism for relieving internal pressure when the internal pressure or temperature of the battery cell 100 reaches a threshold. The end cap assembly 11 can also be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this embodiment of the present application does not impose any specific limitations on this.

[0051] The housing 12 is a component that cooperates with the end cap assembly 11 to form the internal environment of the battery cell 100. This internal environment can be used to accommodate the electrode assembly 13, electrolyte, and other components. The housing 12 and the end cap assembly 11 can be separate components. An opening can be provided in the housing 12, and the end cap assembly 11 is placed over the opening to form the internal environment of the battery cell 100. Alternatively, the end cap assembly 11 and the housing 12 can be integrated. Specifically, the end cap assembly 11 and the housing 12 can form a common connection surface before other components are inserted into the housing. When the interior of the housing 12 is to be enclosed, the end cap assembly 11 is placed over the housing 12. The housing 12 can have a variety of shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, or a hexagonal prism. Specifically, the shape of the housing 12 can be determined based on the specific shape and size of the electrode assembly 13. The housing 12 can be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this embodiment of the present application does not impose any particular limitations on this.

[0052] The electrode assembly 13 is a component in the battery cell 100 where electrochemical reactions occur. One or more electrode assemblies 13 may be contained in the housing 12. The electrode assembly 13 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The parts of the positive and negative electrode sheets with active materials constitute the main body of the battery cell assembly, and the parts of the positive and negative electrode sheets without active materials each constitute a tab. The positive and negative electrode tabs may be located together at one end of the main body or respectively at both ends of the main body. During the charge and discharge process of the battery, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tabs connect the electrode terminals to form a current loop.

[0053] Please refer to Figures 1 to 4 , Figure 4 This is a schematic diagram of the exploded three-dimensional structure of the end cover assembly in a battery cell provided in one embodiment of the present application.

[0054] An embodiment of the present application provides a battery cell 100, which includes an outer shell 10 and a fire extinguishing medium 20, wherein the outer shell 10 includes an end cover assembly 11 and a shell 12, the end cover assembly 11 and the shell 12 together enclose a receiving space 101, and the end cover assembly 11 is provided with a cavity 102 connected to the receiving space 101; the fire extinguishing medium 20 is arranged in the receiving space 101 and / or the cavity 102.

[0055] The housing 10 is an external structural component of the battery cell 100 , and is used to define the external structure of the battery cell 100 and provide a relatively stable and sealed working environment for the normal operation of the battery cell 100 .

[0056] The housing 10 includes an end cap assembly 11 and a shell 12. The end cap assembly 11 and the shell 12 together enclose a receiving space 101. In the embodiments of the present application, the shell 12 is described as having an open structure at one end, with the end cap assembly 11 covering the open end of the shell 12 to form a sealed receiving space 101. In some embodiments, the shell 12 may also be configured as a structure having open ends at both ends. In this case, two end cap assemblies 11 are provided, each covering the two open ends of the shell 12.

[0057] The end cover assembly 11 is provided with a cavity 102 connected to the accommodating space 101. A possible implementation method is that a hollow structure is provided inside the end cover assembly 11, and the hollow structure is connected to the accommodating space 101 through a channel to facilitate heat exchange between the accommodating space 101 and the cavity 102; or, in some embodiments, the surface of the end cover assembly 11 close to the accommodating space 101 may be provided with a blind groove, blind hole or other structure, and the blind groove or blind hole structure is the aforementioned cavity 102.

[0058] The fire extinguishing medium 20 is used when the electrode assembly 13 in the storage space 101 has abnormal conditions such as overheating and short circuit. The fire extinguishing medium 20 can be excited by heat, absorb heat through phase change, and release free radicals that can capture fuel combustion into the storage space 101, thereby providing a self-excited fire extinguishing measure for thermal runaway occurring in the storage space 101, reducing the risk of the fire continuing to develop and spread.

[0059] In the embodiments of the present application, the fire extinguishing medium 20 may be in, but is not limited to, granular, block, or plate form.

[0060] The fire extinguishing medium 20 is arranged in the accommodating space 101 and / or the cavity 102. In the embodiment where the fire extinguishing medium 20 is arranged in the accommodating space 101, a possible implementation method is that the fire extinguishing medium 20 is arranged on the surface of the end cover assembly 11 close to the accommodating space 101 and / or the side wall of the shell 12 corresponding to the gap between the electrode assembly 13 and the end cover assembly 11. In this way, the fire extinguishing medium 20 is directly arranged in the accommodating space 101, and can be activated at the early stage of thermal runaway of the battery cell 100, thereby improving the sensitivity of the fire extinguishing medium 20 to thermal runaway, and controlling and extinguishing the fire at the early stage of thermal runaway.

[0061] Accordingly, since the cavity 102 is connected to the accommodating space 101, the cavity 102 can directly exchange heat with the accommodating space 101. Placing the fire extinguishing medium 20 in the cavity 102 can also enhance the sensitivity of the fire extinguishing medium 20 to the heat changes in the accommodating space 101. Similarly, it can be activated at the early stage of thermal runaway of the battery cell 100, thereby enhancing the sensitivity of the fire extinguishing medium 20 to thermal runaway and controlling and extinguishing the fire in the early stage of thermal runaway.

[0062] In the embodiment where the fire extinguishing medium 20 is disposed in the cavity 102 , the cavity 102 may be used as a storage structure for the fire extinguishing medium 20 . In this case, the fire extinguishing medium 20 may be encapsulated in the hollow space when the end cap assembly 11 is formed.

[0063] In this way, the risk of the fire extinguishing medium 20 contacting other components such as the electrolyte, electrode assembly 13 in the accommodating space 101 can be reduced, which is conducive to maintaining the performance of the fire extinguishing medium 20 itself and can also reduce contamination of the electrolyte or the impact on the normal operation of the electrode assembly 13.

[0064] In some embodiments, the fire extinguishing medium 20 may also be disposed in both the accommodating space 101 and the cavity 102 to further enhance the response rate of the battery cell 100 to a fire and the fire extinguishing effect.

[0065] According to the battery cell 100 provided in the embodiment of the present application, by arranging the fire extinguishing medium 20 in the accommodating space 101 and / or the cavity 102, the fire extinguishing medium 20 can quickly sense temperature changes in the early stage of a fire, thereby improving the fire response sensitivity of the fire extinguishing medium 20; at the same time, such an arrangement enables the fire extinguishing medium 20 to act directly in the accommodating space 101, thereby achieving active fire extinguishing in the early stage of a fire, reducing the risk of thermal runaway of a single battery cell 100 spreading to adjacent battery cells 100, and improving reliability.

[0066] Please refer to Figures 1 to 5 , Figure 5 This is a schematic diagram of the exploded three-dimensional structure of an end cover assembly in a battery cell provided in another embodiment of the present application.

[0067] In some embodiments, the fire extinguishing medium 20 is connected to the end cover assembly 11 , and at least a portion of the fire extinguishing medium 20 protrudes from a surface of the end cover assembly 11 close to the accommodating space 101 .

[0068] At least part of the fire extinguishing medium 20 protrudes from the surface of the end cover assembly 11 close to the accommodating space 101, so that the fire extinguishing medium 20 can directly sense the temperature change in the accommodating space 101, thereby sensing the fire in the accommodating space 101 more quickly.

[0069] That is, a portion of the fire extinguishing medium 20 can be embedded in the end cap assembly 11, with a portion exposed and protruding from the end cap assembly 11, and disposed within the accommodating space 101. In this case, the portion of the fire extinguishing medium 20 embedded in the end cap assembly 11 can greatly enhance the structural stability of the fire extinguishing medium 20. When a fire occurs in the accommodating space 101, the portion of the fire extinguishing medium 20 disposed in the accommodating space 101 is first heated and excited. When this portion of the fire extinguishing medium 20 is completely consumed, the portion of the fire extinguishing medium 20 embedded in the end cap assembly 11 is exposed to the accommodating space 101, where it continues to be excited and absorbs heat from the accommodating space 101.

[0070] In some embodiments, the fire extinguishing medium 20 may be entirely disposed within the accommodation space 101 , so that when a fire occurs in the accommodation space 101 , the fire extinguishing medium 20 is activated as a whole, responding to the fire more quickly and controlling and extinguishing the fire in the early stages of thermal runaway.

[0071] The fire extinguishing medium 20 is connected to the end cover assembly 11. A possible implementation method is that a slot structure is provided on the surface of the end cover assembly 11 close to the accommodating space 101, and the fire extinguishing medium 20 is fastened to the slot structure by a snap-on manner; alternatively, the end cover assembly 11 can be pre-embedded with a metal wire structure during molding, and the fire extinguishing medium 20 is coated on the outer surface of the metal wire structure to achieve the connection between the fire extinguishing medium 20 and the end cover assembly 11.

[0072] In some embodiments, the fire extinguishing medium 20 is disposed within the cavity 102 .

[0073] Cavity 102 may be a hollow structure defined in the center of end cap assembly 11, with a through hole, through slot, or other communication structure defined on a side wall of cavity 102 adjacent to accommodating space 101. In these embodiments of the present application, the design of these through holes, through slot, or other communication structures can be used to simultaneously seal the fire extinguishing medium 20 within cavity 102 while improving the angle at which the fire extinguishing medium 20 is ejected into accommodating space 101 after being activated, thereby allowing the fire extinguishing medium 20 to cover a wider area as possible.

[0074] In these embodiments of the present application, the number of cavities 102 can be, but is not limited to, one, two, or three, and can be selected and designed based on the size of the end cover assembly 11 and the size of the cavity 102 so that the fire extinguishing medium 20 can cover most of the space of the accommodating space 101 when it is activated.

[0075] According to the battery cell 100 provided in the embodiment of the present application, by setting the fire extinguishing medium 20 in the cavity 102, the fire extinguishing medium 20 can be separated from other components in the accommodating space 101, thereby reducing the impact of the fire extinguishing medium 20 on the normal operation of the battery cell 100 when no fire occurs, and quickly responding and extinguishing the fire when a fire occurs.

[0076] In some embodiments, the end cap assembly 11 includes a stacked insulating member 111 and an end cap 112 . The insulating member 111 is located on a side of the end cap 112 close to the accommodating space 101 , and the cavity 102 is disposed in the insulating member 111 .

[0077] The end cap assembly 11 includes a stacked insulating member 111 and an end cap 112. In these embodiments of the present application, the insulating member 111 can be made of plastic, and the end cap 112 can be made of a conductive metal material such as aluminum, magnesium, or stainless steel. In this way, the electrode assembly 13 in the accommodating space 101 can be electrically connected to the outside world by providing a conductive terminal on the end cap 112. The insulating member 111 made of plastic can improve the insulation performance of the battery cell 100. At the same time, the insulating member 111 made of plastic can also reduce the overall weight of the battery cell 100, which is beneficial to improving the weight energy density of the battery cell 100.

[0078] On this basis, the end cap assembly 11 can also be used to seal the open end of the housing 12 to form a sealed and stable accommodation space 101, providing a stable and sealed working environment for the electrode assembly 13. In some embodiments, the end cap assembly 11 can also be provided with structures such as a liquid injection hole, a terminal avoidance hole, and a pressure relief mechanism installation hole that are connected to the accommodation space 101.

[0079] The insulating member 111 is located on a side of the end cover 112 close to the accommodating space 101 , and the cavity 102 is provided on the insulating member 111 so that the cavity 102 is provided close to the accommodating space 101 , which is beneficial to the communication design between the space where the fire extinguishing medium 20 is located (cavity 102 ) and the accommodating space 101 .

[0080] In these embodiments of the present application, the outer dimensions of the insulating member 111 can be slightly smaller than those of the end cap 112 along the direction in which the insulating member 111 and the end cap 112 are stacked, so that the end cap 112 covers the insulating member 111. The insulating member 111 and the end cap 112 can be formed during the ultrasonic welding process of the pole, thereby directly achieving a better bonding strength between the insulating member 111 and the end cap 112 and improving the structural consistency of the end cap assembly 11.

[0081] In some embodiments, the end cover 112 is provided with a pressure relief mechanism 1111 , and along the stacking direction of the insulating member 111 and the end cover 112 , the cavity 102 and the pressure relief mechanism 1111 are arranged opposite to each other.

[0082] The pressure relief mechanism 1111 is used to open when the pressure in the accommodation space 101 is too high, so as to release the pressure in the accommodation space 101 and reduce the risk of explosion of the battery cell 100 due to excessive internal pressure.

[0083] Along the stacking direction of the insulating member 111 and the end cover 112, the cavity 102 and the pressure relief mechanism 1111 are arranged opposite to each other. By limiting the relative position between the cavity 102 and the pressure relief mechanism 1111, the fire extinguishing medium 20 is arranged opposite to the pressure relief mechanism 1111 in the stacking direction of the insulating member 111 and the end cover 112.

[0084] In related technologies, since the pressure relief mechanism 1111 needs to sense the pressure changes in the accommodating space 101, it is usually necessary to leave space at the position of the insulating part 111 corresponding to the location of the pressure relief mechanism 1111, so that the pressure relief mechanism 1111 can be connected to the accommodating space 101 and sense the pressure changes in the accommodating space 101.

[0085] In these embodiments of the present application, cavity 102 is positioned opposite pressure relief mechanism 1111 in order to fully utilize the airtight space on insulating member 111 and reduce the need for irregularly shaped end cap assembly 11. Furthermore, upon activation, pressure relief mechanism 1111 forms a channel on end cap assembly 11 that connects accommodating space 101 to the outside world. In this embodiment of the present application, fire extinguishing medium 20 is positioned corresponding to pressure relief mechanism 1111, thereby providing a barrier for battery cells 100. This prevents heat within accommodating space 101 from radiating outward through the channel formed by pressure relief mechanism 1111, effectively suppressing the spread of fire.

[0086] At the same time, this arrangement allows the pressure relief mechanism 1111 to activate and release pressure when abnormal gas production within the battery cell 100 causes a sharp rise in internal pressure. At this point, the presence of the fire extinguishing medium 20 can also cushion the impact of the high-temperature gas and flames ejected from the pressure relief mechanism 1111 on the outside world. The activation of the fire extinguishing medium 20 helps reduce the rate of pressure rise within the battery cell 100, making the activation process of the pressure relief mechanism 1111 smoother, reducing the risk of secondary damage caused by sudden pressure changes within the battery cell 100, and lowering the probability of electrolyte splashing within the battery cell 100.

[0087] Of course, in these embodiments of the present application, in addition to arranging the cavity 102 at a position opposite to the pressure relief mechanism 1111 along the stacking direction of the insulating member 111 and the end cap 112, the cavity 102 may also be arranged at other positions of the insulating member 111 so as to utilize the fire extinguishing medium 20 in each cavity 102 to jointly extinguish the fire. That is, at least one cavity 102 is arranged at a position on the insulating member 111 opposite to the pressure relief mechanism 1111 along the stacking direction of the insulating member 111 and the end cap 112.

[0088] In some embodiments, the cavity 102 is formed by bending from the insulating member 111 in a direction away from the end cover 112 , and a connecting channel 103 is provided between the cavity 102 and the accommodating space 101 . The connecting channel 103 is provided on the bottom wall and / or side wall of the cavity 102 .

[0089] Cavity 102 is formed by bending from insulating member 111 in a direction away from end cap 112. This is different from the previously described embodiment in which the cavity is formed as a hollow structure within insulating member 111. In these embodiments of the present application, cavity 102 is formed as a whole by protruding from insulating member 111 in a direction closer to accommodation space 101. Therefore, cavity 102 includes side walls formed by bending from insulating member 111 in a direction away from end cap 112, and a bottom wall formed by bending again from the side walls.

[0090] In these embodiments of the present application, since the cavity 102 is formed to protrude as a whole toward the accommodating space 101, the connecting channel 103 can be set on the aforementioned bottom wall and / or side wall of the cavity 102 to achieve communication between the cavity 102 and the accommodating space 101.

[0091] Among them, in the embodiment where the connecting channel 103 is arranged on the bottom wall of the cavity 102, the cavity 102 points to the electrode assembly 13 through the connecting channel 103, so that when a fire occurs, the fire extinguishing medium 20 can directly act on the electrode assembly 13 through the connecting channel 103; in the embodiment where the connecting channel 103 is arranged on the side wall of the cavity 102, the cavity 102 points to the side wall of the shell 12 through the connecting channel 103, which can reduce the contact between the fire extinguishing medium 20 and the electrolyte during the production stage and normal working stage of the battery cell 100, and reduce the risk of mutual interference between the fire extinguishing medium 20 and the electrolyte. The above setting method can be freely selected according to the usage scenario requirements of the battery cell 100.

[0092] In some embodiments, the communication channel 103 has a porous structure, or the communication channel 103 has a grid structure.

[0093] The communication channel 103 has a multi-porous structure, that is, the communication channel 103 is formed by a plurality of small holes spaced apart from each other, and the plurality of small holes are spaced apart from each other to form a porous structure that can support the fire extinguishing medium 20 and allow the fire extinguishing medium 20 to be ejected after the fire extinguishing medium 20 is excited.

[0094] In these embodiments of the present application, the cross-sectional shape of each of the aforementioned small holes can be, but is not limited to, circular, elliptical, triangular, or rectangular. In some embodiments, a plurality of small holes can be arranged in an array so that the fire extinguishing medium 20 is ejected from the cavity 102 more uniformly when activated.

[0095] The connecting channel 103 is in a grid structure, which means that the cross-sectional shape of the connecting channel 103 can be a plurality of mesh-like connecting structures, and the plurality of mesh-like connecting structures can be spaced apart from each other or staggered.

[0096] The mesh-like connecting structure can extend along a straight line or a curve. For example, in some embodiments, the cross-sectional shape of the connecting channel 103 can be configured as a plurality of parallel and spaced straight lines, or as a plurality of concentric circles arranged in sequence, or as a staggered straight line. The above configurations can be freely selected based on the actual needs of the battery cell 100.

[0097] Please refer to Figures 1 to 7 , Figure 6 A cross-sectional view of an insulating member in a battery cell provided in one embodiment of the present application; Figure 7 for Figure 6 An enlarged view of part A of the battery cell is shown.

[0098] In some embodiments, the connecting channel 103 is arranged on the bottom wall of the cavity 102 and includes a plurality of through grooves 1031 arranged in sequence and spaced apart; at least some of the through grooves 1031 connect the cavity 102 with the accommodating space 101 along a direction intersecting with the thickness direction of the bottom wall of the cavity 102.

[0099] The communication channel 103 includes a plurality of through slots 1031 spaced apart in sequence, that is, the cross-sectional shape of the communication channel 103 is an embodiment of a plurality of parallel linear structures spaced apart. Such a structure is easy to form, and the bottom wall of the cavity 102 is more stable.

[0100] In these embodiments of the present application, at least part of the through grooves 1031 connects the cavity 102 with the accommodating space 101 along a direction intersecting with the thickness direction of the bottom wall of the cavity 102, which means that in some of the through grooves 1031, the groove walls of the through grooves 1031 intersect with the thickness direction of the bottom wall of the cavity 102, that is, at least part of the through grooves 1031 are inclined groove bodies. In this way, the direction in which the fire extinguishing medium 20 is ejected from the cavity 102 after being excited can be changed, so that the fire extinguishing medium 20 can cover a larger range of the accommodating space 101 after being excited, further improving the fire extinguishing effect after the fire extinguishing medium 20 is excited.

[0101] For example, the description is made using five through-slots 1031 as an example. The cross-sectional shapes of the five through-slots 1031 are parallel to each other and are independently spaced apart from each other. The five through-slots 1031 are labeled as a first through-slot, a second through-slot, a third through-slot, a fourth through-slot, and a fifth through-slot in the order of arrangement.

[0102] Among them, the third through groove is located at the center position of multiple through grooves 1031. At this time, the groove wall of the third through groove can be set to be parallel to the thickness direction of the bottom wall of the cavity 102, so that the excited fire extinguishing medium 20 can directly act on the center position of the electrode assembly 13 near the end cover assembly 11 when it is ejected through the third through groove.

[0103] The second through-slot and the fourth through-slot are respectively located on both sides of the third through-slot. In this case, the groove walls of the second through-slot and the fourth through-slot can be arranged to intersect with the thickness direction of the bottom wall of the cavity 102, and the end close to the cavity 102 is arranged closer to the third through-slot than the end close to the accommodating space 101, so as to form an "outward" injection structure, so that the excited fire extinguishing medium 20 can "outward" cover a larger range of the electrode assembly 13 when it is injected through the second through-slot or the fourth through-slot.

[0104] The groove wall settings of the first through groove and the fifth through groove are similar to those of the second through groove and the fourth through groove, respectively. In these embodiments of the present application, the slopes of the first through groove and the fifth through groove can be set to be larger to further increase the range of the connecting channel 103 covering the electrode assembly 13.

[0105] It should be noted that this application only uses five through slots 1031 as an example for description. In some embodiments, the number of the first through slot, the second through slot, the third through slot, the fourth through slot and the fifth through slot can also be set to multiple.

[0106] According to the battery cell 100 provided in the embodiment of the present application, the connecting channel 103 is provided to include a plurality of through grooves 1031, and at least a portion of the through grooves 1031 connects the cavity 102 with the accommodating space 101 along an oblique direction. This facilitates the diffusion of heat from various positions in the accommodating space 101 into the cavity 102, further improving the response sensitivity of the fire extinguishing medium 20. At the same time, it can also improve the uniformity of the diffusion of the fire extinguishing medium 20 into the accommodating space 101 after excitation, further improving the fire extinguishing coverage and reliability of the fire extinguishing medium 20.

[0107] In some embodiments, the insulating member 111 is a polyphenylene sulfide sheet or a composite sheet of polypropylene and glass fiber.

[0108] This arrangement can make the insulating part 111 have good heat resistance, and it is not easy to be deformed by heat when a fire occurs, so that the fire extinguishing medium 20 can accurately act in the accommodating space 101 after being activated; at the same time, the insulating part 111 material with higher heat resistance is conducive to locking heat in the battery cell 100 that has thermal runaway, slowing down the rate of heat radiation to other battery cells 100, and improving reliability.

[0109] In some embodiments, the fire extinguishing medium 20 is bonded to the end cap assembly 11 .

[0110] Such a design method is conducive to improving the structural stability of the fire extinguishing medium 20, reducing the risk of the fire extinguishing medium 20 being out of the designed position when bumped, bumped, or dropped, and is conducive to improving the stability of fire extinguishing by the fire extinguishing medium 20.

[0111] In some embodiments, the fire extinguishing medium 20 is a perfluorohexanone sheet, a heptafluoropropane sheet, a perfluoro(2-methyl-3-pentanone) sheet, or an ammonium polyphosphate sheet. This allows the fire extinguishing medium 20 to enhance the flame retardancy of the battery cell 100 after being activated, further improving the reliability of the battery cell 100 in the event of thermal runaway.

[0112] An embodiment of the present application further provides a battery device 1000 , which includes a battery cell 100 provided in any of the aforementioned embodiments.

[0113] An embodiment of the present application further provides an electrical device, which includes the battery device 1000 provided in any of the aforementioned embodiments, and the battery device 1000 is used to provide electrical energy.

[0114] According to some embodiments of this application, please refer to Figures 1 to 7 An embodiment of the present application provides a battery cell 100, which includes a shell 10 and a fire extinguishing medium 20, wherein the shell 10 includes an end cover assembly 11 and a shell 12, the end cover assembly 11 and the shell 12 together enclose a receiving space 101, and the end cover assembly 11 is provided with a cavity 102 connected to the receiving space 101; the fire extinguishing medium 20 is provided in the receiving space 101 and / or the cavity 102.

[0115] The fire extinguishing medium 20 is used when the electrode assembly 13 in the storage space 101 has abnormal conditions such as overheating and short circuit. The fire extinguishing medium 20 can be excited by heat, absorb heat through phase change, and release free radicals that can capture fuel combustion into the storage space 101, thereby providing a self-excited fire extinguishing measure for thermal runaway occurring in the storage space 101, reducing the risk of the fire continuing to develop and spread.

[0116] The fire extinguishing medium 20 is arranged in the accommodating space 101 and / or the cavity 102. In the embodiment where the fire extinguishing medium 20 is arranged in the accommodating space 101, a possible implementation method is that the fire extinguishing medium 20 is arranged on the surface of the end cover assembly 11 close to the accommodating space 101 and / or the side wall of the shell 12 corresponding to the gap between the electrode assembly 13 and the end cover assembly 11. In this way, the fire extinguishing medium 20 is directly arranged in the accommodating space 101, and can be activated at the early stage of thermal runaway of the battery cell 100, thereby improving the sensitivity of the fire extinguishing medium 20 to thermal runaway, and controlling and extinguishing the fire at the early stage of thermal runaway.

[0117] The fire extinguishing medium 20 may be made of perfluorohexanone sheet material, so that the fire extinguishing medium 20 can enhance the flame retardant performance of the battery cell 100 after being excited, further improving the reliability of the battery cell 100 when thermal runaway occurs.

[0118] In some embodiments, the fire extinguishing medium 20 is disposed within the cavity 102 .

[0119] End cap assembly 11 includes a stacked insulating member 111 and an end cap 112. Insulating member 111 is located on the side of end cap 112 adjacent to receiving space 101, and cavity 102 is disposed within insulating member 111. In some embodiments, insulating member 111 may be constructed of polyphenylene sulfide sheet material to enhance its thermal insulation performance, reduce the likelihood of melting in the event of a fire, and improve the structural reliability of end cap assembly 11.

[0120] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0121] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A battery cell, characterized in that: include: The housing comprises an end cap assembly and a shell, wherein the end cap assembly and the shell together enclose a receiving space, and the end cap assembly is provided with a cavity communicating with the receiving space; The fire extinguishing medium is arranged in the accommodating space and / or the cavity.

2. The battery cell according to claim 1, wherein: The fire extinguishing medium is connected to the end cover assembly, and at least a portion of the fire extinguishing medium protrudes from a surface of the end cover assembly close to the accommodating space.

3. The battery cell according to claim 1, wherein: The fire extinguishing medium is arranged in the cavity.

4. The battery cell according to claim 3, characterized in that The end cover assembly includes a stacked insulating member and an end cover. The insulating member is located on a side of the end cover close to the accommodating space, and the cavity is provided on the insulating member.

5. The battery cell according to claim 4, characterized in that The battery cell further includes a pressure relief mechanism, which is provided on the end cover. Along the stacking direction of the insulating member and the end cover, the cavity and the pressure relief mechanism are arranged opposite to each other.

6. The battery cell according to claim 4, characterized in that The cavity is formed by bending from the insulating member in a direction away from the end cover. A communication channel is provided between the cavity and the accommodating space. The communication channel is provided on the bottom wall and / or side wall of the cavity.

7. The battery cell according to claim 6, characterized in that The communication channel is provided on the bottom wall of the cavity and comprises a plurality of through grooves arranged sequentially and spaced apart; At least a portion of the through grooves connects the cavity with the accommodation space along a direction intersecting with a thickness direction of the bottom wall of the cavity.

8. The battery cell according to claim 4, characterized in that The insulating member is a polyphenylene sulfide sheet or a composite sheet of polypropylene and glass fiber.

9. The battery cell according to any one of claims 1 to 8, characterized in that: The fire extinguishing medium is bonded to the end cover assembly.

10. The battery cell according to any one of claims 1 to 8, characterized in that: The fire extinguishing medium is a perfluorohexanone sheet, a heptafluoropropane sheet, a perfluoro(2-methyl-3-pentanone) sheet, or an ammonium polyphosphate sheet.

11. A battery device, characterized in that: The battery cell comprises the battery cell according to any one of claims 1 to 10.

12. An electrical device, characterized in that: The battery device according to claim 11 is used to provide electrical energy.

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