Battery cells, battery devices and electrical equipment

Abstract

The present application discloses a battery cell, a battery device and an electrical equipment. The battery cell includes a shell, a pressure relief mechanism and an electrode assembly. The shell is provided with a storage space for accommodating the electrode assembly, and the shell includes an end cover. The pressure relief mechanism is provided on the end cover. Among them, a first groove and a second groove are provided on the surface of the end cover facing the electrode assembly, the pressure relief mechanism is provided in the first groove, the second groove is interconnected with the first groove, and the second groove is used to guide the gas in the storage space to the pressure relief mechanism. The battery cell, battery device and electrical equipment of the present application can guide the gas inside the battery cell to the pressure relief mechanism, reduce the gas accumulation inside the battery cell, reduce the risk of accidents such as combustion or explosion of the battery cell, and improve the stability of the operation of the battery cell.

Description

Technical Field

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

[0002] Batteries are widely used in various electronic devices, such as mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy airplanes, electric toy ships, power tools and energy storage systems, etc.

[0003] At present, how to improve the stability of battery cells during operation and reduce the incidence of accidents such as combustion and explosion is one of the issues being studied in this field. 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 guide the gas inside the battery cell to the pressure relief mechanism, reduce the gas accumulation inside the battery cell, reduce the risk of accidents such as combustion or explosion of the battery cell, and improve the stability of the battery cell operation.

[0005] In a first aspect, the present application provides a battery cell, including a housing, a pressure relief mechanism, and an electrode assembly. The housing is provided with a storage space for accommodating the electrode assembly, and the housing includes an end cover. The pressure relief mechanism is provided on the end cover. A first groove and a second groove are provided on the surface of the end cover facing the electrode assembly, the pressure relief mechanism is provided in the first groove, the second groove is connected to the first groove, and the second groove is used to guide the gas in the storage space to the pressure relief mechanism.

[0006] In the technical solution of the embodiment of the present application, by providing a shell to accommodate the electrode assembly, damage to the electrode assembly caused by external impurities and moisture is reduced, and a stable environment is provided for the operation of the electrode assembly. The electrode assembly is an important component for converting electrical energy and chemical energy in the battery cell. By providing a second groove on the end cover, the gas accumulated in the accommodating space is guided to the second groove, and then through the second groove to the first groove. The first groove guides the gas to the pressure relief mechanism, reducing the accumulation of gas in the shell, improving the convenience of gas discharge, allowing the pressure relief mechanism to open the valve normally, reducing the risk of accidents such as combustion and explosion in the battery cell, thereby improving the operating stability of the battery cell.

[0007] In some embodiments, the electrode assembly is a wound electrode, and there is a gap between the wound electrode and the shell, and the second groove extends to the range of the gap. The electrode assembly is wound into the shell, which can improve the utilization rate of the internal space of the shell and improve the energy density of the battery cell. The second groove extends to the gap between the electrode assembly and the shell, and is connected to the space in the gap, which reduces the accumulation of gas inside the electrode assembly, makes the pressure relief mechanism open the valve more smoothly, and improves the stability of the operation of the battery cell.

[0008] In some embodiments, the electrode assembly further includes a tab, and the first groove is used to accommodate at least part of the tab. In the above structure, the tab is provided to transmit the electrical energy in the electrode assembly, and the first groove accommodates the tab. The provision of the first groove can increase the space inside the housing to accommodate other parts of the electrode assembly, thereby increasing the energy density of the battery cell and facilitating the connection between the tab and the end cap.

[0009] In some embodiments, the end cap includes a body, a first protrusion, and a second protrusion. The first protrusion protrudes along a side surface of the body away from the accommodating space, and the first groove extends from the body into the first protrusion. The second protrusion protrudes along a side surface of the body away from the accommodating space, and the second groove extends from the body into the second protrusion. In the above structure, the first protrusion and the second protrusion can use the space outside the end cap to provide space for the first groove and the second groove.

[0010] In some embodiments, the minimum distance M between the second protrusion and the edge of the end cap satisfies 0<M≤20mm. The above structure extends the second protrusion to the edge of the end cap, which facilitates the second groove to extend to the gap between the electrode assembly and the shell, guides the gas in the side space to the pressure relief mechanism, and improves the exhaust efficiency.

[0011] In some embodiments, the maximum height of the first protrusion along the thickness direction of the main body is H1, and the maximum height of the second protrusion along the thickness direction of the main body is H2, and H1 and H2 satisfy H2≤H1. In the above structure, reducing the protrusion height of the second protrusion can provide installation space for the connecting bar in the battery module and reduce the risk of interference between the second protrusion and other components.

[0012] In some embodiments, an electrode terminal is also provided on the end cap. The battery cell also includes a transition piece, which includes a first connection portion connected to the pole ear and a second connection portion connected to the electrode terminal, and the first connection portion is bent in the direction of the first groove. In the above structure, by setting a click terminal, it is convenient to connect the battery cell with other components to transmit the electric energy generated by the electrode assembly. One end of the transition piece connected to the pole ear is bent toward the first groove, which reduces the space inside the shell occupied by the first connection portion, improves the utilization rate of the space inside the shell, and thus improves the energy density of the battery cell.

[0013] In some embodiments, the battery cell further includes an insulating member, which is disposed between the end cap and the electrode assembly, and is used to insulate the electrode assembly from the end cap. In the above structure, by providing the insulating member, the creepage distance between the electrode assembly and the end cap is increased, the insulation protection performance is improved, and the risk of short circuit of the housing is reduced.

[0014] In some embodiments, the insulating member is provided with a vent hole, which is connected to the second groove. In the above structure, by providing the vent hole on the insulating member, the gas in the electrode assembly can be discharged into the first groove through the vent hole, and discharged from the pressure relief mechanism under certain conditions, thereby reducing the risk of internal gas accumulation in the battery cell and improving the reliability of the battery cell operation.

[0015] In some embodiments, the surface of the insulating member facing the electrode assembly is concave to form a third groove, and the orthographic projection of the third groove on the end cap at least partially overlaps with the first groove. The insulating member is also provided with a pressure relief hole, and the orthographic projection of the pressure relief hole on the end cap at least partially falls within the range of the first groove. In the above structure, by providing the third groove, the shape of the insulating member and the end cap are matched, the assembly efficiency is improved, and the setting of the adapter and the pole ear is facilitated, and the compactness of the setting of each component inside the shell is improved, thereby improving the energy density of the battery cell.

[0016] In some embodiments, the surface of the insulating member facing the electrode assembly is concave to form a fourth groove, the fourth groove extends along the direction of the bent portion toward the straight portion, and the fourth groove extends to communicate with the third groove. In the above structure, the gas inside the electrode assembly is guided to the third groove by providing the fourth groove, and then the gas is guided to the first groove through the pressure relief hole, and finally can be discharged through the pressure relief mechanism, so the fourth groove can increase the speed of gas discharge.

[0017] In some embodiments, the orthographic projection of the fourth groove on the end cover at least partially falls within the range of the second groove. In the above structure, the fourth groove is arranged corresponding to the second groove, which improves the compactness of the structure and the efficiency of gas discharge.

[0018] In some embodiments, the insulating member includes an insulating body, a third protrusion, and a fourth protrusion. The third protrusion protrudes along a side surface of the insulating body away from the accommodating space, and the third groove extends from the insulating body into the third protrusion. The fourth protrusion protrudes along a side surface of the insulating body away from the accommodating space, and the fourth groove extends from the insulating body into the fourth protrusion. In the above structure, by providing the third protrusion and the fourth protrusion, the space between the insulating member and the end cover is utilized to facilitate the accommodation of the third groove and the fourth groove, thereby improving the compactness of the structure and the space utilization rate.

[0019] In a second aspect, the present application provides a battery device, which includes the battery cell in the above embodiment.

[0020] In a third aspect, the present application provides an electrical device, which includes the battery device in the above embodiment, and the battery device is used to provide electrical energy.

[0021] 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

[0022] The features, advantages and technical effects of exemplary embodiments of the present application will be described below with reference to the accompanying drawings.

[0023] Figure 1 A schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0024] Figure 2 A schematic diagram of the exploded structure of a battery device provided in some embodiments of the present application;

[0025] Figure 3 A schematic diagram of the exploded structure of a battery cell provided in some embodiments of the present application;

[0026] Figure 4 A schematic diagram of the structure of an end cover of a battery cell provided in some embodiments of the present application;

[0027] Figure 5 A schematic diagram of the structure of an insulating member of a battery cell provided in some embodiments of the present application;

[0028] Figure 6 A schematic diagram of the structure of an insulating member of a battery cell provided in some other embodiments of the present application;

[0029] Figure 7 A schematic diagram of the structure of a battery cell provided in some embodiments of the present application;

[0030] Figure 8 A front view of a battery cell provided for some embodiments of the present application;

[0031] Fig. 9 for Figure 8 Structural diagram of the AA section;

[0032] Fig.10 for Fig. 9 A schematic diagram of the enlarged structure at B in the middle;

[0033] Fig.11 A schematic structural diagram of an insulating component of a battery cell provided in some other embodiments of the present application.

[0034] DETAILED DESCRIPTION OF REFERENCE NUMERALS

[0035] 1. Vehicle; 2. Battery device; 3. Controller; 4. Motor; 5. Box; 51. First box part; 52. Second box part; 6. Battery cell; 10. Electrode assembly; 11. Straight part; 12. Bend part; 20. Shell; 21. Gap; 24. Pressure relief mechanism; 25. Electrode terminal; 30. End cover; 301. Second groove; 302. First groove; 303. First protrusion; 304. Second protrusion; 305. Main body; 40. Shell; 50. Adapter; 60. Insulator; 601. Vent; 602. Third groove; 603. Fourth groove; 604. Pressure relief hole; 605. Insulating body; 606. Third protrusion; 607. Fourth protrusion. DETAILED DESCRIPTION

[0036] The following embodiments of the technical solution of the present application will be described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0038] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0039] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0040] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: 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 associated objects before and after are in an "or" relationship.

[0041] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0042] In the description of the embodiments of the present application, the technical 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. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0043] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0044] The term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0045] In the embodiments of the present application, the same reference numerals represent 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 the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

[0046] During the operation of the battery cell, a certain amount of gas will be generated due to the redox reaction between the negative electrode and the electrode liquid, the decomposition of the solid electrolyte interface film, and the release of active oxygen by the active material on the positive electrode. The gas accumulates inside the battery cell, which can easily cause the shell of the battery cell to crack, or even cause risks such as combustion and explosion due to increased temperature. In order to reduce the various damages caused by the increase in gas volume mentioned above, a pressure relief mechanism is usually set on the outer shell of the battery cell. The pressure relief mechanism is configured to open when the pressure inside the battery cell reaches a threshold, discharge the high-temperature and high-pressure substances inside the battery cell, and reduce the risk of combustion or explosion of the battery cell.

[0047] However, in order to improve the utilization rate of the internal space of the battery cell, the volume of the electrode assembly is usually increased, so the gap between the electrode assembly and the shell is further compressed, and even part of the surface of the electrode assembly is completely fitted with the shell. The above-mentioned structural setting makes it impossible for some of the gas generated by the electrode assembly to be discharged through the gap between the electrode assembly and the shell. In the exhaust gap formed between the bent portion of the electrode assembly and the shell, a large amount of gas is accumulated in the gap between the bent portion of the electrode assembly and the shell, and cannot be discharged normally from the pressure relief mechanism. The pressure relief mechanism cannot be opened normally, and the risk of battery cell operation is greatly increased.

[0048] Based on the above situation, the embodiment of the present application provides a battery cell, which is provided with a shell to accommodate the electrode assembly, reduce the damage to the electrode assembly caused by external impurities and moisture, and provide a stable environment for the operation of the electrode assembly. The electrode assembly is an important component for converting electrical energy and chemical energy in the battery cell. The electrode assembly is formed into a straight portion and a bent portion after winding and shaping, which can be easily loaded into the shell, and can improve the utilization rate of the internal space of the shell and improve the energy density of the battery cell. Furthermore, by providing a second groove on the end cover, the gas accumulated in the gap between the bent portion and the shell is guided to the second groove, and then from the second groove to the first groove, and then from the first groove to the pressure relief mechanism for discharge, so as to reduce the accumulation of gas in the shell, improve the convenience of gas discharge, so that the pressure relief mechanism can open the valve normally, reduce the risk of accidents such as combustion and explosion of the battery cell, and thus improve the operation stability of the battery cell.

[0049] The battery apparatus mentioned in the embodiments of the present application may include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly may include multiple battery cells, which are connected in series, in parallel or in mixed connection through a busbar component.

[0050] In some embodiments, a battery cell assembly is generally formed by arranging a plurality of battery cells; as an example, a battery cell assembly may be a battery module, and a battery module is formed by arranging and fixing a plurality of battery cells to form an independent module. As an example, a battery module may be formed by bundling a plurality of battery cells by a cable tie.

[0051] In some embodiments, the battery device may be a battery pack, which includes a case and one or more battery cell assemblies, wherein the battery cell assemblies are accommodated in the case.

[0052] As an example, the battery cell assembly may be a battery module, and the battery cell assembly may be accommodated in the box by fixing the battery module in the box.

[0053] As an example, the battery cell assembly may also be housed in the case by directly fixing a plurality of battery cells to the case.

[0054] In the embodiment of the present application, the battery cell may be a secondary battery cell, which refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0055] Battery cells may include but are not limited to lithium ion battery cells, sodium ion battery cells, sodium lithium ion battery cells, lithium metal battery cells, sodium metal battery cells, lithium sulfur battery cells, magnesium ion battery cells, nickel metal hydride battery cells, nickel cadmium battery cells, lead storage battery cells, etc.

[0056] As an example, the battery cell may be a cylindrical battery cell, a prismatic battery cell or a battery cell of other shapes. The prismatic battery cell includes a square shell battery cell, a blade-shaped battery cell, a polygonal battery, such as a hexagonal battery, etc. There is no particular limitation in the present application.

[0057] In some embodiments, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0058] In some embodiments, the battery device may be an energy storage device, which includes an energy storage container, an energy storage cabinet, and the like.

[0059] The battery device disclosed in the embodiments of the present application can be used in various energy storage systems that use the battery device as a power source or use the battery device as an energy storage element. The electrical device can be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, and the like. Among them, the electric toy can include a fixed or mobile electric toy, for example, a game console, an electric car toy, an electric ship toy, and an electric airplane toy, and the like, and the spacecraft can include an airplane, a rocket, a space shuttle, and a spacecraft, and the like.

[0060] For the convenience of description, the following embodiments are described by taking the electric device as a vehicle as an example.

[0061] Figure 1 A schematic diagram of the structure of a vehicle provided for some embodiments of the present application.

[0062] like Figure 1 As shown, a battery device 2 is disposed inside the vehicle 1, and the battery device 2 may be disposed at the bottom, head, or tail of the vehicle 1. The battery device 2 may be used to power the vehicle 1, for example, the battery device 2 may be used as an operating power source for the vehicle 1.

[0063] The vehicle 1 may further include a controller 3 and a motor 4 , wherein the controller 3 is used to control the battery device 2 to supply power to the motor 4 , for example, to meet the power requirements of starting, navigating and driving the vehicle 1 .

[0064] In some embodiments of the present application, the battery device 2 can not only serve as an operating power source for the vehicle 1, but also serve 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.

[0065] Figure 2 Schematic diagram of the exploded structure of a battery device provided in some embodiments of the present application.

[0066] The box 5 is used to accommodate the battery cell 6, and the box 5 can be of various structures. In some embodiments, the box 5 can include a first box portion 51 and a second box portion 52, the first box portion 51 and the second box portion 52 cover each other, and the first box portion 51 and the second box portion 52 jointly define a storage space 53 for accommodating the battery cell. The first box portion 51 can be a hollow structure with one end open, and the second box portion 52 is a plate-like structure, and the second box portion 52 covers the open side of the first box portion 51 to form a box 5 with a storage space 53; the first box portion 51 and the second box portion 52 can also be hollow structures with one side open, and the open side of the first box portion 51 covers the open side of the second box portion 52 to form a box 5 with a storage space 53. Of course, the first box portion 51 and the second box portion 52 can be of various shapes, such as a cylinder, a cuboid, etc.

[0067] In order to improve the sealing performance after the first box body 51 and the second box body 52 are connected, a sealing member, such as a sealant, a sealing ring, etc., may also be provided between the first box body 51 and the second box body 52 .

[0068] Assuming that the first box body portion 51 covers the top of the second box body portion 52 , the first box body portion 51 can also be referred to as an upper box cover, and the second box body portion 52 can also be referred to as a lower box body.

[0069] In the battery device 2, the battery cell 6 can be one or more. If there are more than one battery cell 6, the battery cells 6 can be connected in series, in parallel or in mixed connection. Mixed connection means that the battery cells 6 are both connected in series and in parallel. The battery cells 6 can be directly connected in series, in parallel or in mixed connection, and then the whole formed by the battery cells 6 is accommodated in the box 5; of course, the battery cells can also be connected in series, in parallel or in mixed connection to form a battery module, and then the battery modules are connected in series, in parallel or in mixed connection to form a whole, and then accommodated in the box 5.

[0070] In some optional embodiments, the battery cells 6 may also be directly accommodated in the box body 5 to reduce the connecting components or supporting components required to form the battery module and improve the energy density of the battery device 2 .

[0071] For example, the battery cell 6 may be the smallest unit constituting the battery device 2 .

[0072] Figure 3 A schematic diagram of the exploded structure of a battery cell provided in some embodiments of the present application.

[0073] like Figure 3 As shown, in some embodiments, the battery cell 6 includes a housing 40 and an electrode assembly 10 accommodated in the housing 40 .

[0074] The electrode assembly 10 includes a positive electrode and a negative electrode. During the charge and discharge process of the battery cell 6, active ions (such as lithium ions) are inserted and removed back and forth between the positive electrode and the negative electrode. Optionally, the electrode assembly 10 also includes a separator disposed between the positive electrode and the negative electrode, which can reduce the risk of short circuit between the positive and negative electrodes while allowing active ions to pass through.

[0075] The housing 40 is used to encapsulate the electrode assembly 10 and the electrolyte and other components. The housing 40 may be a steel housing, an aluminum housing, a plastic housing (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing 40 ), or an aluminum-plastic film.

[0076] In some embodiments, the housing 40 includes a shell 20 and an end cover 30 . The shell 20 has an opening, and the end cover 30 is used to cover the opening.

[0077] In some embodiments, the battery cell 6 further includes an electrolyte contained in the housing 40. The electrolyte plays a role in conducting ions between the positive and negative electrodes and can be in liquid, gel or solid state.

[0078] In some embodiments, the battery cell 6 includes an electrode terminal 25 . The electrode terminal 25 is electrically connected to the electrode assembly 10 to output or input electrical energy of the battery cell 6 .

[0079] In some embodiments, the battery cell 6 includes a pressure relief mechanism 24, which is used to rupture when the internal pressure of the battery cell 6 exceeds a threshold value to release the pressure inside the battery cell 6. Specifically, the pressure relief mechanism 24 can be an element or component that is actuated when the battery cell 6 reaches a certain condition. Optionally, the housing 40 includes an end cap 30 and a shell 20. The shell 20 has an opening, and the end cap 30 covers the opening and is sealed and connected to the shell 20.

[0080] Please refer to Figures 3 to 5 , Figure 3 A schematic diagram of the exploded structure of a battery cell 6 provided in some embodiments of the present application, Figure 4 This is a schematic diagram of the structure of the end cover 30 of the battery cell 6 provided in some embodiments of the present application. Figure 5 A schematic structural diagram of an insulating member 60 of a battery cell 6 provided in some embodiments of the present application.

[0081] As shown in the figure, the embodiment of the present application provides a battery cell 6, including a shell 40, a pressure relief mechanism 24 and an electrode assembly 10. The shell 40 is provided with a storage space for accommodating the electrode assembly 10, and the shell 40 includes an end cover 30. The pressure relief mechanism 24 is arranged on the end cover 30. Among them, the surface of the end cover 30 facing the electrode assembly 10 is provided with a first groove 302 and a second groove 301, the pressure relief mechanism 24 is arranged in the first groove 302, and the second groove 301 is connected with the first groove 302. The second groove 301 is used to guide the gas in the storage space to the first groove 302, and the first groove 302 guides the gas to the pressure relief mechanism 24 for discharge.

[0082] The electrode assembly 10 includes a plurality of stacked positive electrode sheets, negative electrode sheets, and separators. Exemplarily, the stacked positive electrode sheets, negative electrode sheets, and separators are wound to form a cylindrical body, and the cylindrical body is rolled to form an electrode assembly 10 with a flat middle and bent sides. The two sides of the middle straight portion 11 are connected to the bent portions 12. Such a structure is easy to be loaded into the square housing 40, and a gap 21 is formed between the bent portion 12 and the shell wall of the square shell 20.

[0083] The shell 40 includes an end cap 30 and a shell 20, the electrode assembly 10 is arranged in the shell 20, the shell 20 has an opening, and the end cap 30 covers the opening. Exemplarily, a pressure relief mounting hole is provided on the end cap 30, and a pressure relief mechanism 24 is provided in the pressure relief mounting hole. The pressure relief mechanism 24 includes a pressure relief sheet, and the edge of the pressure relief sheet is sealed and connected to the hole wall of the pressure relief mounting hole. A weak portion may be provided on the pressure relief sheet. The weak portion may rupture under a certain pressure to release the substance inside the shell 40. The shell 40 may be manufactured using a material with a certain structural strength, such as aluminum alloy, stainless steel, etc.

[0084] One end of the second groove 301 extends to the gap 21 between the electrode assembly 10 and the housing 40 , and the other end of the second groove 301 extends to the first groove 302 , so that the gap 21 and the pressure relief mechanism 24 can communicate with each other.

[0085] In the technical solution of the embodiment of the present application, the housing 40 is provided to contain the electrode assembly 10, thereby reducing the damage to the electrode assembly 10 caused by external impurities and moisture, and providing a stable environment for the operation of the electrode assembly 10. The electrode assembly 10 is an important component in the battery cell 6 for converting electrical energy and chemical energy.

[0086] Furthermore, by providing a second groove 301 on the end cover 30, the gas accumulated in the gap 21 is guided to the pressure relief mechanism 24, thereby reducing the accumulation of gas in the outer shell 40 and improving the convenience of gas discharge, so that the pressure relief mechanism 24 can open the valve normally, reducing the risk of accidents such as combustion and explosion of the battery cell 6, thereby improving the operating stability of the battery cell 6.

[0087] In some embodiments of the present application, the electrode assembly 10 is a wound electrode, and there is a gap 21 between the wound electrode and the housing 40, and the second groove 301 extends to the range of the gap 21. The electrode assembly 10 is wound into the housing 40, which can improve the utilization rate of the internal space of the housing 40 and improve the energy density of the battery cell 6. The second groove 301 extends to the gap 21 between the electrode assembly 10 and the housing 40, and is connected to the space of the gap 21, which reduces the accumulation of gas inside the electrode assembly 10, makes the pressure relief mechanism 24 open the valve more smoothly, and improves the stability of the operation of the battery cell 6.

[0088] In some embodiments of the present application, the electrode assembly 10 further includes a tab, and the first groove 302 is used to accommodate at least a portion of the tab.

[0089] The tabs are connected to the electrode plates, and the tabs include positive tabs and negative tabs. The positive tabs are connected to the positive plates, and the negative tabs are connected to the negative plates. The tabs transmit the electrical energy generated on the electrode plates to the circuit system outside the battery.

[0090] The first groove 302 formed by the concave surface of one side of the end cap 30 corresponding to the pole ear can accommodate at least part of the pole ear, effectively utilize the space of the end cap 30, and reduce the volume occupied by the pole ear inside the shell 20, thereby providing more space for other battery components (such as diaphragms, electrolytes, etc.). This space optimization improves the energy density of the battery cell 6 because more active substances can be encapsulated in a limited volume. The presence of the first groove 302 also simplifies the connection process between the pole ear and the end cap 30. Since the pole ear is partially accommodated by the groove, it is easier to achieve precise alignment and fixation during the assembly process, reducing the difficulty and cost of assembly. The first groove 302 indirectly improves the overall safety of the battery by optimizing the internal layout and reducing unnecessary structural interference. For example, reducing the crowding of the internal space can reduce the risk of short circuits caused by mechanical stress or thermal stress.

[0091] In the above structure, a pole ear is provided to transmit the electrical energy in the electrode assembly 10, and the first groove 302 accommodates the pole ear. The setting of the first groove 302 can increase the space inside the shell 20 to accommodate other parts of the electrode assembly 10, thereby improving the energy density of the battery cell 6 and facilitating the connection between the pole ear and the end cover 30.

[0092] like Figure 7 As shown, in some embodiments of the present application, the end cover 30 includes a body portion 305, a first protrusion portion 303, and a second protrusion portion 304. The first protrusion portion 303 protrudes along a side surface of the body portion away from the accommodation space, and the first groove 302 extends from the body portion 305 into the first protrusion portion 303. The second protrusion portion 304 protrudes along a side surface of the body portion 305 away from the accommodation space, and the second groove 301 extends from the body portion into the second protrusion portion 304. In the above structure, the first protrusion portion 303 and the second protrusion portion 304 can use the space outside the end cover to provide space for the arrangement of the first groove 302 and the second groove 301.

[0093] like Figure 8 As shown, in some embodiments of the present application, the minimum distance M between the second protrusion 304 and the edge of the end cover 30 satisfies 0<M≤20mm. The above structure extends the second protrusion 304 to the edge of the end cover 30, which facilitates the second groove 301 to extend to the gap 21 between the electrode assembly 10 and the housing 40, and guides the gas in the side space to the pressure relief mechanism 24, thereby improving the exhaust efficiency.

[0094] like Fig. 9 as well as Fig.10As shown, in some embodiments of the present application, the maximum height of the first protrusion 303 protruding along the thickness direction of the main body 305 is H1, and the maximum height of the second protrusion 304 protruding along the thickness direction of the main body 305 is H2, and H1 and H2 satisfy that H2≤H1. In the above structure, reducing the protrusion height of the second protrusion 304 can provide installation space for the connection bar in the battery module and reduce the risk of interference between the second protrusion 304 and other components.

[0095] In some embodiments of the present application, the pressure relief mechanism 24 is disposed in the first groove 302 , and the second groove 301 is connected to the first groove 302 .

[0096] The pressure relief mechanism 24 is disposed in the first groove 302 and connected thereto through the second groove 301, and the space of the first groove 302 is used to guide the gas. When the internal pressure of the battery increases, the gas will flow from the electrode sheet to the gap 21 between the bent portion 12 and the housing 20, and then enter the second groove 301 from the gap 21, and then enter the first groove 302 through the second groove 301, and finally be guided to the pressure relief mechanism 24. This structure increases the speed of gas flow, making the pressure relief process faster and more efficient.

[0097] Furthermore, the first groove 302 can not only guide the gas, but also accommodate part of the gas to a certain extent. This accommodation effect helps to reduce the degree of gas accumulation inside the electrode assembly 10, and reduce the direct impact and damage of the gas on the internal structure of the battery. At the same time, it also provides more response time for the pressure relief mechanism 24, making the valve opening process smoother and more stable. By quickly and effectively releasing the accumulated gas, the fluctuation amplitude of the internal pressure of the battery can be reduced, thereby maintaining the stability of the operation of the battery cell 6, and can extend the battery life, improve battery performance and stabilize operation.

[0098] In some embodiments of the present application, the end cap 30 is further provided with an electrode terminal 25. The battery cell 6 further includes a transition piece 50, which includes a first connection portion connected to the tab and a second connection portion connected to the electrode terminal 25, and the first connection portion is bent toward the first groove 302.

[0099] By bending the first connecting portion and directing it toward the first groove 302, the space of the shell 20 occupied by the adapter 50 is reduced, so that more space can be used to accommodate other key components such as the electrode assembly 10 and the electrolyte, thereby improving the overall energy density of the battery cell 6. The bending can also reduce the interference and collision between the adapter 50 and other internal components. Inside the battery cell 6, the space is usually very limited and compact, and any unnecessary interference may lead to performance degradation or safety hazards. Therefore, reducing these interferences through reasonable layout and structural design can effectively improve the operating stability of the battery cell 6. The bent design can also improve the connection stability between the first connecting portion and the pole ear. After bending, the contact area between the adapter 50 and the pole ear is increased and the contact angle is improved, thereby improving the low resistance and high efficiency during the power transmission process.

[0100] In some embodiments of the present application, there are two bending portions 12, which are respectively connected to the two ends of the straight portion 11 along the first direction X. The number of second grooves 301 is correspondingly two, and the two second grooves 301 are respectively arranged on both sides of the first groove 302 along the first direction X.

[0101] There are two bends 12, and the two bends 12 are respectively connected to the two ends of the straight portion 11 along the first direction X, which is the most common structure of the wound electrode assembly 10. There are two corresponding second grooves 301, which are respectively arranged on both sides of the first groove 302 along the first direction X. This symmetrical layout enables the gas generated by the battery cell 6 on both sides along the first direction X to be promptly guided into the first groove 302. When the pressure inside the battery increases due to overcharging, short circuit or other abnormal conditions, the gas on both sides can quickly enter the first groove 302 through their respective second grooves 301, and then be guided to the pressure relief mechanism 24 for release. This design increases the speed of gas discharge and reduces the degree of gas accumulation inside the electrode assembly 10, thereby effectively reducing the risk of combustion and explosion during the operation of the battery cell 6.

[0102] In some optional embodiments, there are multiple second grooves 301 at any end along the first direction X. Exemplarily, the first direction X is the width direction of the battery cell 6, and multiple second grooves 301 can be arranged at intervals along the thickness direction of the battery cell 6, so as to further improve the efficiency of gas guidance, reduce the accumulation of gas inside the housing 20, and improve the stability of the operation of the battery cell 6.

[0103] In some embodiments of the present application, the battery cell 6 further includes an insulating member 60 , which is disposed between the end cover 30 and the electrode assembly 10 , and is used to insulate the electrode assembly 10 from the end cover 30 .

[0104] The insulating member 60 is disposed between the end cap 30 and the electrode assembly 10, and its main function is to provide electrical insulation, that is, to block direct electrical contact between the electrode assembly 10 and the end cap 30. By providing the insulating member 60, the creepage distance between the electrode assembly 10 and the end cap 30 is increased, thereby improving the insulation protection performance.

[0105] Exemplarily, the insulating member 60 is generally made of a material with good insulating properties, such as plastic, rubber or ceramic. These materials can effectively isolate the electric field between the electrode assembly 10 and the end cap 30, and prevent the charge from leaking through the air or other media. Therefore, the presence of the insulating member 60 greatly improves the insulation protection performance of the battery cell 6 and reduces the risk of short circuit of the housing 40.

[0106] In some optional embodiments, the adapter plate 50 is disposed on a side of the insulating member 60 that is away from the end cover 30. The above structure can achieve effective insulation between the adapter plate 50 and the end cover 30.

[0107] In some optional embodiments, the insulating member 60 may be made of a material with a lower melting point, which can melt when the temperature of the electrode assembly 10 is high, so that the gas inside the electrode assembly 10 can more smoothly reach the second groove 301 and be discharged through the pressure relief mechanism 24. Generally, the accumulation of gas inside the electrode assembly 10 is accompanied by a temperature increase, so the gas barrier effect of the insulating member 60 can be eliminated by melting, and the gas can be discharged smoothly.

[0108] like Figure 5 As shown, in some embodiments of the present application, a vent hole 601 is provided on the insulating member 60 , and the vent hole 601 is communicated with the second groove 301 .

[0109] The vent 601 is provided on the insulating member 60, which not only maintains the integrity of the insulating member, but also allows the gas to be discharged smoothly. When gas is generated inside the battery due to factors such as charging and discharging, temperature increase, etc., these gases will enter the second groove 301 through the vent 601, and then be guided into the first groove 302, and finally discharged from the battery cell 6 through the pressure relief mechanism 24. The connection design between the vent 601 and the second groove 301 improves the discharge efficiency of the gas inside the battery. In the absence of the vent 601, the gas may need to bypass multiple obstacles to reach the discharge port, which not only increases the resistance to discharge, but also may cause gas accumulation inside the battery. By directly providing the vent 601 on the insulating member 60 and connecting it to the second groove 301, the gas can be discharged more directly and quickly, thereby reducing the risk of internal gas accumulation in the battery cell 6 and improving the reliability of the operation of the battery cell 6.

[0110] In some embodiments of the present application, there are multiple vent holes 601 , and the multiple vent holes 601 are arranged at intervals along the direction of the bending portion 12 toward the pressure relief mechanism 24 .

[0111] The provision of multiple vents 601 provides more discharge channels for the gas inside the electrode assembly 10. When gas is generated inside the battery, the gas can quickly enter the second groove 301 through the nearest vent 601 and be guided into the first groove 302. Compared with a single vent 601, multiple vents 601 can improve the gas discharge efficiency and reduce the gas accumulation time inside the battery.

[0112] Optionally, the diameter and shape of the vent 601 can be determined according to the specific needs and structure of the battery cell 6 to ensure that it can meet the needs of gas discharge without negatively affecting the insulation performance of the insulating member. The vents 601 should be spaced along the direction of the bend 12 toward the pressure relief mechanism 24 to ensure that the gas can flow smoothly and reach the pressure relief valve. At the same time, the layout and structure of other components inside the battery must also be considered to avoid conflict or interference between the vent 601 and other components. The insulating member 60 should be made of a material with good insulation properties and mechanical strength to ensure that it will not deform or rupture when subjected to internal gas pressure.

[0113] By providing a plurality of vent holes 601 , the efficiency of gas discharge from the electrode assembly 10 is improved, so that the pressure relief valve can be opened smoothly, thereby reducing the risk of combustion and explosion of the battery cell 6 caused by poor opening of the pressure relief valve.

[0114] like Figure 6 As shown, in some embodiments of the present application, the insulating member 60 is concave toward the surface of the electrode assembly 10 to form a third groove 602, and the orthographic projection of the third groove 602 on the end cover 30 at least partially overlaps with the first groove 302. A pressure relief hole 604 is also provided on the insulating member 60, and the orthographic projection of the pressure relief hole 604 on the end cover 30 at least partially falls within the range of the first groove 302.

[0115] The surface of the insulating member 60 facing the electrode assembly 10 is concave to form a third groove 602, and the insulating member 60 has a higher shape matching with the end cover 30. During the assembly process, the assembly error can be reduced and the assembly efficiency can be improved. At the same time, the existence of the third groove 602 also provides more space for the setting of the adapter 50 and the tab, so that these components can be arranged more compactly inside the battery cell 6.

[0116] By designing the third groove 602, the space between the insulating member 60 and the end cover 30 is more effectively utilized. This helps to achieve a compact layout of the components inside the housing 40 and reduce unnecessary space waste. The compact layout can not only improve the energy density of the battery cell 6, but also enhance its structural stability.

[0117] The pressure relief hole 604 is at least partially arranged corresponding to the first groove 302 on the end cover 30. When the internal pressure of the battery increases abnormally, the gas can quickly enter the first groove 302 through the pressure relief hole 604 and be smoothly guided to the pressure relief mechanism 24 for release. This design improves the response speed and safety of the battery cell 6 when dealing with abnormal internal pressure.

[0118] The communication design between the pressure relief hole 604 and the first groove 302 enables the battery cell 6 to quickly release gas when the internal pressure is too high, thereby reducing the risk of explosion caused by gas accumulation.

[0119] In the above structure, by setting the third groove 602, the insulating part 60 is matched with the shape of the end cover 30, which improves the efficiency of assembly, facilitates the setting of the adapter 50 and the pole ear, and improves the compactness of the setting of each component inside the shell 40, thereby improving the energy density of the battery cell 6.

[0120] like Figure 6 As shown, in some embodiments of the present application, the insulating member 60 is concave toward the surface of the electrode assembly 10 to form a fourth groove 603, and the fourth groove 603 extends along the bending portion 12 toward the straight portion 11, and the fourth groove 603 extends to communicate with the third groove 602.

[0121] The fourth groove 603 extends along the direction of the bent portion 12 toward the straight portion 11, and is finally connected to the third groove 602, so that the gas generated inside the electrode assembly 10 can flow quickly along the fourth groove 603 to the first groove 302, reducing the accumulation of gas inside the electrode assembly 10. When gas is generated inside the battery, the gas can quickly enter the third groove 602 through the fourth groove 603, and further be guided to the pressure relief mechanism 24 for discharge through the pressure relief hole 604 and the first groove 302. The design of the fourth groove 603 being connected with the third groove 602, the pressure relief hole 604 and the first groove 302 makes the gas discharge path inside the battery cell 6 more direct and efficient. This design not only improves the efficiency of gas discharge, but also optimizes the layout of the internal components of the battery cell 6.

[0122] In the above structure, the gas inside the electrode assembly 10 is guided to the third groove 602 by setting the fourth groove 603, and then the gas is guided to the first groove 302 through the pressure relief hole 604, and finally can be discharged through the pressure relief mechanism 24, so the fourth groove 603 can increase the speed of gas discharge.

[0123] In some embodiments of the present application, the orthographic projection of the fourth groove 603 on the end cover 30 at least partially falls within the range of the second groove 301 .

[0124] The corresponding arrangement of the fourth groove 603 and the second groove 301 makes the gas discharge path inside the battery cell 6 more direct and efficient. This design reduces unnecessary space waste and improves the compactness of the internal structure. By matching the positions of the fourth groove 603 and the second groove 301, the space inside the battery cell 6 is more effectively utilized, which helps to improve the energy density of the battery and also enhances the overall structural strength of the battery cell 6.

[0125] Due to the corresponding arrangement of the fourth groove 603 and the second groove 301, the gas generated inside the electrode assembly 10 can enter the second groove 301 more directly through the fourth groove 603, and then be guided to the pressure relief mechanism 24 for discharge, thereby improving the efficiency of gas discharge and reducing the retention time of the gas inside the battery cell 6. The smooth connection between the fourth groove 603 and the second groove 301 reduces the resistance during the gas flow, so that the gas can be discharged from the battery cell 6 more smoothly. This helps to reduce the increase in internal pressure caused by gas accumulation and improves the safety of the battery cell 6.

[0126] In the above structure, the fourth groove 603 is arranged corresponding to the second groove 301, which improves the compactness of the structure and the efficiency of gas exhaust.

[0127] like Figure 7 As shown, in some optional embodiments, the surface of the end cap 30 facing away from the electrode assembly 10 protrudes to form a first protrusion 303, and the first protrusion 303 is formed by the second groove 301 protruding from the inner side of the end cap 30. It can be understood that the second groove 301 is formed by the inner side of the end cap 30 being pressed outwardly deformed, and the second groove 301 is formed on the inner side of the end cap 30 facing the electrode assembly 10, and the first protrusion 303 is formed on the outer side of the end cap 30 facing away from the electrode assembly 10. Similarly, the surface of the end cap 30 facing away from the electrode assembly 10 protrudes to form a second protrusion 304, and the second protrusion 304 is formed by the first groove 302 protruding from the inner side of the end cap 30.

[0128] like Fig.10 as well as Fig.11As shown, in some embodiments of the present application, the insulating member 60 includes an insulating body 605, a third protrusion 606, and a fourth protrusion 607. The third protrusion 606 protrudes along a side surface of the insulating body away from the accommodation space, and the third groove 602 extends from the insulating body 605 into the third protrusion 606. The fourth protrusion 607 protrudes along a side surface of the insulating body 605 away from the accommodation space, and the fourth groove 603 extends from the insulating body 605 into the fourth protrusion 607. In the above structure, by providing the third protrusion 606 and the fourth protrusion 607, the space between the insulating member 60 and the end cover 30 is utilized to facilitate the accommodation of the third groove 602 and the fourth groove 603, thereby improving the compactness of the structure and the space utilization rate.

[0129] In some optional embodiments, the battery cell 6 includes a shell 40 and an electrode assembly 10. The shell 40 includes an end cap 30, and a pressure relief mechanism 24 is provided on the end cap 30. The electrode assembly 10 is arranged in the shell 40, and the electrode assembly 10 includes a straight portion 11 and a bent portion 12, and the straight portion 11 is arranged opposite to the pressure relief mechanism 24. Among them, the surface of the end cap 30 facing the electrode assembly 10 is concave to form a second groove 301. The second groove 301 extends along the direction of the bent portion 12 toward the straight portion 11, and extends to communicate with the pressure relief mechanism 24 to guide the gas generated by the electrode assembly 10 to the pressure relief mechanism 24. The pressure relief mechanism 24 is provided in the first groove 302, and the second groove 301 is connected to the first groove 302. The end cap 30 is also provided with an electrode terminal 25. The battery cell 6 also includes a transition piece 50, and the transition piece 50 includes a first connection portion connected to the pole ear and a second connection portion connected to the electrode terminal 25, and the first connection portion is bent in the direction of the first groove 302. The battery cell 6 also includes an insulating member 60, which is disposed between the end cap 30 and the electrode assembly 10, and is used to insulate the electrode assembly 10 from the end cap 30. The surface of the insulating member 60 facing the electrode assembly 10 is concave to form a third groove 602, and the orthographic projection of the third groove 602 on the end cap 30 at least partially overlaps with the first groove 302. The insulating member 60 is also provided with a pressure relief hole 604, and the orthographic projection of the pressure relief hole 604 on the end cap 30 at least partially falls within the range of the first groove 302. The surface of the insulating member 60 facing the electrode assembly 10 is concave to form a fourth groove 603, and the fourth groove 603 extends along the direction of the bent portion 12 toward the straight portion 11, and the fourth groove 603 extends to communicate with the third groove 602. The orthographic projection of the fourth groove 603 on the end cap 30 at least partially falls within the range of the second groove 301.

[0130] The embodiment of the present application provides a battery device 2, which includes the battery cell 6 in the above embodiment. The embodiment of the present application also provides an electrical device, which includes the battery device 2 in the above embodiment, and the battery device 2 is used to provide electrical energy. The battery device 2 and the electrical device both include the battery cell 6 in the above embodiment. The battery cell 6 is provided with a shell 40 to accommodate the electrode assembly 10, thereby reducing the damage to the electrode assembly 10 caused by external impurities and moisture, and providing a stable environment for the operation of the electrode assembly 10. The electrode assembly 10 is an important component for converting electrical energy and chemical energy in the battery cell 6. The electrode assembly 10 is formed into a straight portion 11 and a bent portion 12 after winding and shaping, which can be easily loaded into the shell 40, and can improve the utilization rate of the internal space of the shell 40, and improve the energy density of the battery cell 6.

[0131] In particular, by providing a second groove 301 on the end cover 30, the gas accumulated in the space between the bent portion 12 and the outer shell 40 is guided to the first groove 302 through the second groove 301, and then guided to the pressure relief mechanism 24 for discharge through the first groove 302, thereby reducing the accumulation of gas in the outer shell 40 and improving the convenience of gas discharge, so that the pressure relief mechanism 24 can open the valve normally, reducing the risk of accidents such as combustion and explosion of the battery cell 6, thereby improving the operating stability of the battery cell 6.

[0132] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: Electrode assembly, A housing having a receiving space for receiving the electrode assembly, wherein the housing includes an end cover; A pressure relief mechanism, provided on the end cover; Among them, the surface of the end cover facing the electrode assembly is provided with a first groove and a second groove, the pressure relief mechanism is arranged in the first groove, the second groove is connected with the first groove, and the second groove is used to guide the gas in the accommodating space to the pressure relief mechanism.

2. The battery cell according to claim 1, characterized in that: The electrode assembly is a wound electrode, a gap is provided between the wound electrode and the shell, and the second groove extends to the range of the gap.

3. The battery cell according to claim 1, characterized in that: The electrode assembly further includes a pole lug, and the first groove is used to accommodate at least a portion of the pole lug.

4. The battery cell according to claim 3, characterized in that: The end cap comprises: Body part; A first protrusion protrudes along a surface of the main body away from the accommodating space, and the first groove extends from the main body to the first protrusion; The second protrusion protrudes along a side surface of the main body away from the accommodating space, and the second groove extends from the main body to the inside of the second protrusion.

5. The battery cell according to claim 4, characterized in that: The minimum distance M between the second protrusion and the edge of the end cover satisfies 0<M≤20mm.

6. The battery cell according to claim 4, characterized in that: The maximum height of the first protrusion along the thickness direction of the main body is H1, and the maximum height of the second protrusion along the thickness direction of the main body is H2. H1 and H2 satisfy H2≤H1.

7. The battery cell according to any one of claims 3 to 6, characterized in that: The end cap is also provided with an electrode terminal. The battery cell further includes a transfer plate, wherein the transfer plate includes a first connection portion connected to the electrode tab and a second connection portion connected to the electrode terminal, and the first connection portion is bent toward the first groove.

8. The battery cell according to any one of claims 4 to 6, characterized in that: The battery cell further includes an insulating member, which is disposed between the end cover and the electrode assembly, and is used to insulate the electrode assembly from the end cover.

9. The battery cell according to claim 8, characterized in that: The insulating member is provided with a vent hole, and the vent hole is communicated with the second groove.

10. The battery cell according to claim 8, characterized in that: The insulating member is concave on the surface of the electrode assembly to form a third groove, and the orthographic projection of the third groove on the end cover at least partially overlaps with the first groove. The insulating member is also provided with a pressure relief hole, and the orthographic projection of the pressure relief hole on the end cover at least partially falls within the range of the first groove.

11. The battery cell according to claim 10, characterized in that: The surface of the insulating member facing the electrode assembly is concave to form a fourth groove, and the fourth groove extends to communicate with the third groove.

12. The battery cell according to claim 11, characterized in that: The orthographic projection of the fourth groove on the end cover at least partially falls within the range of the second groove.

13. The battery cell according to claim 12, characterized in that: The insulating member comprises: Insulation body; a third protrusion protruding along a side surface of the insulating body away from the accommodating space, and the third groove extending from the insulating body to the inside of the third protrusion; A fourth protrusion protrudes along a side surface of the insulating body away from the accommodating space, and the fourth groove extends from the insulating body to the inside of the fourth protrusion.

14. A battery device, characterized in that: The invention comprises a battery cell as claimed in any one of claims 1 to 13.

15. An electrical equipment, characterized in that: The electrical equipment comprises the battery device as claimed in claim 14, wherein the battery device is used to provide electrical energy.

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