Battery cell, battery, and electrical device

Abstract

Provided are a battery cell (20), a battery (100), and an electrical device. The battery cell (20) comprises a casing (21), an electrode assembly (22), and an insulating protective layer (23), the insulating protective layer (23) covering the electrode assembly (22). In the battery cell (20) provided in the embodiments of the present application, the insulating protective layer (23) is used to wrap the electrode assembly (22), and the electrode assembly (22) and the casing (21) are separated by means of the insulating protective layer (23), so as to increase the creepage distance between the casing (21) and the electrode assembly (22). Thus, the aim of increasing the breakdown voltage between the casing (21) and the electrode assembly (22) is achieved, thereby effectively improving the high-voltage breakdown resistance of the casing (21) and reducing the probability of combustion or explosion of the battery cell (20).

Description

Battery cells, batteries and electrical equipment

[0001] This application refers to Chinese patent application No. 202311271481.5 filed on September 28, 2023, entitled “Battery Cell, Battery and Electrical Equipment”, which is incorporated into this application in its entirety by reference. Technical Field

[0002] The present application relates to the technical field of battery structures, and in particular provides a battery cell, a battery, and an electrical device. Background Art

[0003] In the related art, multiple battery cells are connected in series and then in parallel to form a group; however, multiple battery cells connected in series will generate high voltage. When one of the battery cells melts, a high voltage will be generated between the outer shell of the battery cell and the electrode assembly. The shell is prone to the risk of high-voltage breakdown, which may lead to the risk of combustion or explosion of the battery cell.

[0004] Application Contents

[0005] The purpose of the embodiments of the present application is to provide a battery cell, a battery, and an electrical device, aiming to solve the problem that the outer shell of the battery cell is prone to high-voltage breakdown in a high-voltage environment.

[0006] To achieve the above objectives, the technical solutions adopted in the embodiments of the present application are:

[0007] In a first aspect, an embodiment of the present application provides a battery cell, comprising a housing, an electrode assembly, and an insulating protective layer. The housing has a receiving cavity, the electrode assembly is disposed in the receiving cavity, and the insulating protective layer covers the electrode assembly.

[0008] Beneficial effects of the embodiments of the present application: The battery cell provided in the embodiments of the present application utilizes an insulating protective layer to cover the electrode assembly, and the electrode assembly and the outer shell are separated by the insulating protective layer to increase the creepage distance between the outer shell and the electrode assembly, thereby achieving the purpose of increasing the breakdown voltage between the outer shell and the electrode assembly, and further effectively improving the high-voltage breakdown resistance of the outer shell, thereby reducing the probability of combustion or explosion of the battery cell.

[0009] In some embodiments, the outer shell includes an end cover and a shell, a accommodating cavity with an opening is formed on the shell, and the end cover is arranged at the opening; a lower plastic layer is provided on the inner surface of the end cover, and the lower plastic layer is at least partially connected to the insulating protective layer to form a sealed connection section.

[0010] By adopting the above-mentioned technical solution, at least a portion of the lower plastic layer is connected to at least a portion of the insulating protective layer to form a sealed connection section, and the lower plastic layer and the insulating protective layer are used together to provide insulating protection for the electrode assembly, thereby further increasing the creepage distance between the electrode assembly and the outer shell, thereby further increasing the breakdown voltage between the outer shell and the electrode assembly, and optimizing the high-voltage breakdown resistance of the shell, thereby further reducing the probability of combustion or explosion of the battery cell.

[0011] In some embodiments, the battery cell further includes an adapter plate, which is electrically connected to the electrode assembly, and a sealed connection section is provided between at least a portion of the adapter plate and the shell.

[0012] By adopting the above-mentioned technical solution, a sealed connection section is set between at least part of the adapter and the shell, that is, the lower plastic layer and the insulating protective layer between at least part of the adapter and the shell are connected to form a separation, thereby effectively improving the creepage distance between the adapter and the shell, thereby improving the high-voltage breakdown resistance of the shell.

[0013] In some embodiments, the housing includes a plurality of side walls, and a sealing connection section is provided between the adapter piece and each side wall.

[0014] By adopting the above-mentioned technical solution, a sealed connection section is formed between the adapter and each side wall of the shell by connecting them through the lower plastic layer and the insulating protective layer, so that the creepage distance between the adapter and each side wall of the shell is improved, that is, the breakdown voltage between the adapter and any side surface of the shell is improved, and the high-voltage breakdown resistance of the shell is effectively improved.

[0015] In some embodiments, the adapter piece has an outer edge portion, and the sealing connection section is configured to block the shortest path from the outer edge portion to the side wall.

[0016] By adopting the above-mentioned technical solution, the sealed connection section can block the shortest path from the outer edge to the side wall, and the creepage distance between any point on the outer edge and the side wall on either side can be increased, thereby improving the breakdown voltage between the adapter and any side surface of the shell, and effectively improving the high-voltage breakdown resistance of the shell.

[0017] In some embodiments, the sealing connection section is annular and wound around the adapter plate.

[0018] By adopting the above technical solution, the sealing connection section is wrapped around the adapter plate, that is, the sealing connection section can fully separate the adapter plate and the shell, effectively improving the breakdown voltage between the adapter plate and the shell, and the high-voltage breakdown resistance of the shell is effectively improved.

[0019] In some embodiments, a gap is provided between the adapter piece and the sealing connection section.

[0020] By adopting the above-mentioned technical solution, the sealing connection section and the adapter plate are arranged at intervals, that is, there is a gap between the connection between the lower plastic layer and the insulating protective layer and the adapter plate, thereby effectively improving the convenience of connecting the lower plastic layer and the insulating protective layer and reducing the interference effect between the sealing connection section and the adapter plate.

[0021] In some embodiments, the gap width between the adapter piece and the sealing connection section is M, 0<M≤50mm.

[0022] By adopting the above-mentioned technical solution, the gap width between the adapter and the sealing connection section is set to be greater than 0 and less than or equal to 50 mm. The sealing connection section can form a gap with the adapter, effectively insulating the adapter to achieve the purpose of increasing the creepage distance between the adapter and the shell and improving the adapter's resistance to high-voltage breakdown.

[0023] In some embodiments, the width of the gap between the adapter piece and the sealing connection section is M, and 3 mm ≤ M ≤ 10 mm.

[0024] By adopting the above-mentioned technical solution, the gap width between the adapter and the sealing connection section is set to be greater than or equal to 3 mm and less than or equal to 10 mm. The sealing connection section can form a gap with the adapter, effectively insulating the adapter to achieve the purpose of increasing the creepage distance between the adapter and the shell and improving the adapter's resistance to high-voltage breakdown.

[0025] In some embodiments, the sealing connection section has a sealing width N, 0<N≤3 mm.

[0026] By adopting the above technical solution, the sealing width of the sealing connection section is set to be greater than 0 and less than or equal to 3 mm, so that the connection between the lower plastic layer and the insulating protective layer has a certain sealing width to ensure the insulating protection performance of the sealing connection section.

[0027] In some embodiments, the sealed connection section has a sealing width N, 1 mm ≤ N ≤ 3 mm.

[0028] By adopting the above-mentioned technical solution, the sealing width of the sealed connection section is set to be greater than or equal to 1 mm and less than or equal to 3 mm, so that the connection between the lower plastic layer and the insulating protective layer has a certain sealing width to ensure the insulating protection performance of the sealed connection section.

[0029] In some embodiments, the insulating protective layer includes a first insulating portion and a second insulating portion, a sealing fold is provided between the first insulating portion and the second insulating portion, and the first insulating portion and / or the second insulating portion is configured to be able to bend around the sealing fold.

[0030] By adopting the above-mentioned technical solution, the first insulating part can be used to insulate and protect the side of the electrode assembly, and the first insulating part and / or the second insulating part can be used to insulate and protect the bottom of the electrode assembly after being bent around the sealing fold, thereby effectively improving the insulating protection effect of the insulating protective layer on the electrode assembly.

[0031] In a second aspect, an embodiment of the present application further provides a battery comprising the battery cell as described above.

[0032] Beneficial effects of the embodiments of the present application: The battery provided by the embodiments of the present application includes the above-mentioned battery cell. On the basis that the shell of the battery cell has better resistance to high-voltage breakdown, the probability of combustion or explosion of the battery can be effectively reduced.

[0033] In a third aspect, an embodiment of the present application further provides an electrical device comprising the battery as described above.

[0034] Beneficial effects of the embodiments of the present application: The electrical equipment provided by the embodiments of the present application includes the above-mentioned battery. On the basis of the low probability of combustion or explosion of the battery, the probability of combustion or explosion of the electrical equipment is also low. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or related technical descriptions. 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.

[0036] FIG1 is a schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0037] FIG2 is an exploded view of a battery provided in some embodiments of the present application;

[0038] FIG3 is a schematic diagram of the exploded structure of a battery cell provided in some embodiments of the present application;

[0039] FIG4 is a schematic diagram of the internal structure of a battery cell provided in some embodiments of the present application;

[0040] FIG5 is a partial enlarged schematic diagram of point A in FIG4 ;

[0041] FIG6 is a partial enlarged schematic diagram of point B in FIG4 ;

[0042] FIG7 is a schematic structural diagram of an end cap provided in some embodiments of the present application;

[0043] FIG8 is a schematic diagram showing the positional relationship between an adapter sheet and a sealing connector provided in some embodiments of the present application;

[0044] FIG9 is a schematic diagram showing the positional relationship between another adapter plate and a sealing connector provided in some embodiments of the present application.

[0045] Among them, the figure marks are: battery 100, controller 200, motor 300; box body 10, first part 11, second part 12; battery cell 20, outer shell 21, accommodating cavity 21a, end cover 211, electrode terminal 211a, shell 212, electrode assembly 22, tab 22a, connecting cavity 221, insulating protective layer 23, first insulating part 231, second insulating part 232, sealing fold 233, lower plastic layer 24, sealing connecting section 25, adapter plate 26, first adapter part 261, second adapter part 262, outer edge part 263. DETAILED DESCRIPTION

[0046] The following describes in detail embodiments of the present application, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0047] In the description of this application, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0048] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0049] In this application, unless otherwise expressly specified or limited, terms such as "mounted," "connected," "connect," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components or interactions between two components. Those skilled in the art will understand the specific meanings of these terms in this application based on specific circumstances.

[0050] Currently, market developments indicate that power batteries are becoming increasingly widely used. They are not only used in energy storage systems such as hydropower, thermal, wind, and solar power plants, but are also widely used in electric vehicles like electric bicycles, electric motorcycles, and electric vehicles, as well as in military equipment and aerospace. As power battery applications continue to expand, market demand is also growing.

[0051] Battery cells are generally connected in series or parallel to form battery modules or batteries for use. During the operation of the battery or battery module, a battery cell may melt. At this time, a high voltage may be generated between the electrode assembly and the shell of the battery cell, and the shell is prone to the risk of high-voltage breakdown, which may lead to the risk of combustion or explosion of the battery cell.

[0052] Based on the above considerations, in order to solve the problem that the outer shell of the battery cell is prone to high-voltage breakdown in a high-voltage environment, a battery cell is designed, in which an insulating protective layer is wrapped around the electrode assembly so that the insulating protective layer can separate the electrode assembly and the outer shell, thereby increasing the creepage distance between the outer shell and the electrode assembly, thereby achieving the purpose of increasing the breakdown voltage between the outer shell and the electrode assembly, and further effectively improving the high-voltage breakdown resistance of the shell, thereby reducing the probability of combustion or explosion of the battery cell.

[0053] The battery cells disclosed in the embodiments of the present application can be used in electrical devices that use batteries as power sources or various energy storage systems that use batteries as energy storage elements. Electrical devices may include, but are not limited to, mobile phones, tablets, laptops, electric toys, power tools, battery-powered vehicles, electric vehicles, ships, spacecraft, and the like. Electric toys may include fixed or mobile electric toys, such as game consoles, electric vehicle toys, electric ship toys, and electric airplane toys, and spacecraft may include airplanes, rockets, space shuttles, and spacecraft, and the like.

[0054] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present application.

[0055] Please refer to Figure 1, which is a schematic structural diagram of a vehicle 1000 provided in some embodiments of the present application. The vehicle 1000 can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000, and the battery 100 can be provided at the bottom, head or tail of the vehicle 1000. The battery 100 can be used to power the vehicle 1000. For example, the battery 100 can serve as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0056] In some embodiments of the present application, the battery 100 can serve not only as an operating power source for the vehicle 1000, but also as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0057] Please refer to Figure 2, which is an exploded view of a battery 100 provided in some embodiments of the present application. The battery 100 includes a housing 10 and a battery cell 20, with the battery cell 20 housed within the housing 10. The housing 10 provides a storage space for the battery cell 20 and can have various structures. In some embodiments, the housing 10 can include a first portion 11 and a second portion 12, which overlap each other and together define a storage space for the battery cell 20. The second portion 12 can be a hollow structure with one end open. The first portion 11 can be a plate-like structure, with the first portion 11 overlapping the open side of the second portion 12, so that the first portion 11 and the second portion 12 together define a storage space. Alternatively, the first portion 11 and the second portion 12 can each be a hollow structure with one end open, with the open side of the first portion 11 overlapping the open side of the second portion 12. Of course, the housing 10 formed by the first portion 11 and the second portion 12 can have various shapes, such as a cylinder, a rectangular parallelepiped, etc.

[0058] In the battery 100, there may be multiple battery cells 20, and the multiple battery cells 20 may be connected in series, in parallel, or in a hybrid connection. A hybrid connection refers to a combination of series and parallel connections among the multiple battery cells 20. The multiple battery cells 20 may be directly connected in series, in parallel, or in a hybrid connection, and then the entire battery cell 20 may be housed within the housing 10. Alternatively, the battery 100 may be constructed by first connecting multiple battery cells 20 in series, in parallel, or in a hybrid connection to form a battery module, which is then connected in series, in parallel, or in a hybrid connection to form a complete battery module, and then housed within the housing 10. The battery 100 may also include other structures, such as a busbar assembly for electrically connecting the multiple battery cells 20.

[0059] Each battery cell 20 may be a secondary battery or a primary battery, and may also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 20 may be cylindrical, flat, rectangular, or in other shapes.

[0060] Please refer to Figure 3, which shows an exploded schematic diagram of a battery cell 20 provided in some embodiments of the present application. A battery cell 20 is the smallest unit of a battery. As shown in Figure 3, a battery cell 20 includes a housing 21, an electrode assembly 22, and other functional components. The housing 21 includes an end cap 211 and a casing 212.

[0061] The end cap 211 is a component that covers the opening of the housing 212 to isolate the internal environment of the battery cell 20 from the external environment. The shape of the end cap 211 can be adapted to the shape of the housing 212 to match the housing 212. Optionally, the end cap 211 can be made of a material with a certain hardness and strength (such as an aluminum alloy). This makes the end cap 211 less likely to deform when subjected to compression or collision, thereby providing the battery cell 20 with greater structural strength and improved reliability. Functional components such as electrode terminals 211a can be provided on the end cap 211. The electrode terminal 211a can be used to electrically connect to the electrode assembly 22 for outputting or inputting electrical energy from the battery cell 20; wherein the electrode terminal 211a includes a positive electrode post, a negative electrode post, an upper plastic, etc., one end of the positive electrode post and the negative electrode post can be directly connected to the bus bar, and the other end of the positive electrode post and the negative electrode post can be connected to one of the poles of the adjacent battery cell 20 in the battery 100 or the battery module. In some embodiments, the end cap 211 can also be provided with a pressure relief mechanism for releasing the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold value. The material of the end cap 211 can also be various, for example, the material of the end cap 211 includes but is not limited to copper, iron, aluminum, stainless steel, aluminum alloy, etc.

[0062] The housing 212 is a component that cooperates with the end cap 211 to form the internal environment of the battery cell 20. This internal environment can be used to accommodate the electrode assembly 22, electrolyte, and other components. The housing 212 and the end cap 211 can be separate components. An opening can be provided in the housing 212, and the end cap 211 can be placed over the opening to form the internal environment of the battery cell 20. Alternatively, the end cap 211 and the housing 212 can be integrated. Specifically, the end cap 211 and the housing 212 can form a common connection surface before other components are inserted into the housing. When the interior of the housing 212 is to be enclosed, the end cap 211 is placed over the housing 212. The housing 212 can have a variety of shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the housing 212 can be determined based on the specific shape and size of the electrode assembly 22. The housing 212 can be made of a variety of materials, including, but not limited to, copper, iron, aluminum, stainless steel, and aluminum alloys.

[0063] The electrode assembly 22 is a component in the battery cell 20 where electrochemical reactions occur. One or more electrode assemblies 22 may be contained in the housing 212. The electrode assembly 22 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 electrode assembly 22, and the parts of the positive and negative electrode sheets without active materials each constitute a tab 22a. The positive tab and the negative tab 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 active material and the negative active material react with the electrolyte, and the tab 22a connects the electrode terminals to form a current loop.

[0064] According to some embodiments of the present application, please refer to Figures 3 and 4. The embodiments of the present application provide a battery cell 20, including a shell 21, an electrode assembly 22 and an insulating protective layer 23. The shell 21 has a accommodating cavity 21a, the electrode assembly 22 is arranged in the accommodating cavity 21a, and the insulating protective layer 23 is coated on the electrode assembly 22.

[0065] Among them, the insulating protective layer 23 is an insulating layer structure, and the insulating protective layer 23 can be but is not limited to an insulating coating, an insulating film, an insulating adhesive layer, etc.; the insulating protective layer 23 can be directly connected to the electrode assembly 22, for example, by coating, bonding, etc., and is set on the outer surface of the electrode assembly 22; or, the insulating protective layer 23 can be set on the outer surface of the electrode assembly 22 by sleeves or wrapping.

[0066] It can be understood that the electrode assembly 22 is arranged in the accommodating cavity 21a of the shell 21, and the distance between the electrode assembly 22 and the shell 21 is small, so the creepage distance between the electrode assembly 22 and the shell 21 is small. When a high voltage environment is formed between the electrode assembly 22 and the shell 21, the shell 21 is prone to the risk of high-voltage breakdown; therefore, the electrode assembly 22 is covered with an insulating protective layer 23 to separate the electrode assembly 22 and the shell 21, so that the creepage distance between the electrode assembly 22 and the shell 21 can be increased. Therefore, the electrode assembly 22 and the shell 21 can withstand higher voltages without being broken down, that is, the breakdown voltage between the shell 21 and the electrode assembly 22 is improved, and the high-voltage breakdown resistance of the shell 21 is also effectively improved.

[0067] The battery cell 20 provided in the embodiment of the present application utilizes an insulating protective layer 23 to cover the electrode assembly 22, and the electrode assembly 22 and the outer shell 21 are separated by the insulating protective layer 23 to increase the creepage distance between the outer shell 21 and the electrode assembly 22, thereby achieving the purpose of increasing the breakdown voltage between the outer shell 21 and the electrode assembly 22, and further effectively improving the high-voltage breakdown resistance of the outer shell 21, thereby reducing the probability of combustion or explosion of the battery cell 20.

[0068] According to some embodiments of the present application, please refer to Figures 3 to 5. The outer shell 21 includes an end cover 211 and a shell body 212. A accommodating cavity 21a with an opening is formed on the shell body 212, and the end cover 211 is arranged at the opening; a lower plastic layer 24 is provided on the inner surface of the end cover 211, and the lower plastic layer 24 is at least partially connected to the insulating protective layer 23 to form a sealed connection section 25.

[0069] The lower plastic layer 24 is disposed on the inner wall of the end cap 211 and is used to insulate and protect the inner wall of the end cap 211. The lower plastic layer 24 can be fixed to the inner wall of the end cap 211 by adhesion. It is understood that the inner wall of the end cap 211 refers to the wall surface of the end cap 211 facing the housing 212.

[0070] The aforementioned sealed connection section 25 refers to the point where the lower plastic layer 24 and the insulating protective layer 23 are connected. It is understood that the lower plastic layer 24 and the insulating protective layer 23 can be connected by hot melting, whereby portions of the lower plastic layer 24 and the insulating protective layer 23 are melted, and then the melted portions of the lower plastic layer 24 and the insulating protective layer 23 are fused together. After cooling, the lower plastic layer 24 and the insulating protective layer 23 form an integrated structure, and the point where the lower plastic layer 24 and the insulating protective layer 23 are integrated is the sealed connection section 25. Alternatively, the lower plastic layer 24 and the insulating protective layer 23 can be connected by bonding, whereby portions of the lower plastic layer 24 and the insulating protective layer 23 are fixedly bonded together, so that the point where the lower plastic layer and the insulating protective layer 23 are bonded together is the sealed connection section 25.

[0071] Optionally, the insulating protective layer 23 can be connected to the end face of the lower plastic layer 24 facing the electrode assembly 22, that is, the sealing connection section 25 formed by the insulating protective layer 23 and the lower plastic layer 24 is formed on the end face of the lower plastic layer 24 facing the electrode assembly 22; or, the insulating protective layer 23 can also be connected to the side where the lower plastic layer 24 intersects with the inner wall of the end cover 211, and the sealing connection section 25 formed by the insulating protective layer 23 and the lower plastic layer 24 is formed on the side where the lower plastic layer 24 intersects with the inner wall of the end cover 211, that is, the insulating protective layer 23 is coated on the electrode assembly 22 and extends toward the end cover 211, and the insulating protective layer 23 can be coated on the outer surface of the lower plastic layer 24 (the side of the lower plastic layer 24) and form the sealing connection section 25. As shown in Figure 7, the insulating protective layer 23 can be connected to the side of the lower plastic layer 24 in the figure and at the position shown by the hatched line.

[0072] The insulating protective layer 23 may be partially connected to the lower plastic layer 24 , or the insulating protective layer 23 may surround the lower plastic and be connected to the lower plastic to form a circle of sealed connection section 25 .

[0073] In this way, at least a portion of the lower plastic layer 24 is connected to at least a portion of the insulating protective layer 23 to form a sealed connection section 25. The lower plastic layer 24 and the insulating protective layer 23 are used together to provide insulating protection for the electrode assembly 22, thereby further improving the creepage distance between the electrode assembly 22 and the outer shell 21, thereby further improving the breakdown voltage between the outer shell 21 and the electrode assembly 22, and optimizing the high-voltage breakdown resistance of the shell 212, thereby further reducing the probability of combustion or explosion of the battery cell 20.

[0074] According to some embodiments of the present application, referring to FIG. 3 to FIG. 7 , the battery cell 20 further includes a transition piece 26 , which is electrically connected to the electrode assembly 22 , and a sealing connection section 25 is provided between at least a portion of the transition piece 26 and the shell 212 .

[0075] The adapter plate 26 is used to connect the poles (including the positive pole and the negative pole) provided on the end cap 211 and the tabs of the electrode assembly 22 to establish current conduction. It is understood that the adapter plate 26 is generally located between the electrode assembly 22 and the end cap 211 and is in contact with the poles on the end cap 211. The other portion of the adapter plate 26 is located within the accommodating cavity 21a and is in contact with the tabs of the electrode assembly 22.

[0076] Adapter plate 26 is electrically charged, and thus high voltages may form between adapter plate 26 and the housing 212, as well as between the welds between the housing 212 and the end cap 211. A sealed connection section 25 is formed between adapter plate 26 and the housing 212 using the lower plastic layer 24 and the insulating protective layer 23. This sealed connection section 25 separates adapter plate 26 from the housing 212, increasing the creepage distance between adapter plate 26 and the housing 212 and thereby improving the housing 212's ability to withstand high-voltage breakdown.

[0077] Optionally, a sealing connection section 25 can be set between the shell 212 and part of the adapter plate 26; or, a sealing connection section 25 can be set between both the shell 212 and the adapter plate 26, that is, the sealing connection section 25 can surround the adapter plate 26 to improve the creepage resistance between the adapter plate 26 and the shell 212.

[0078] In this way, by setting a sealed connection section 25 between at least part of the adapter plate 26 and the shell 212, that is, the lower plastic layer 24 and the insulating protective layer 23 between at least part of the adapter plate 26 and the shell 212 are connected to form a partition, the creepage distance between the adapter plate 26 and the shell 212 is effectively increased, thereby improving the high-voltage breakdown resistance of the shell 212.

[0079] According to some embodiments of the present application, referring to FIG. 4 to FIG. 9 , the housing 212 includes a plurality of side walls, and a sealing connection section 25 is provided between the adapter piece 26 and each side wall.

[0080] The side wall of the housing 212 refers to a wall surface surrounding the housing 212 in the height direction. It can be understood that one end of the side wall of the housing 212 in the height direction is surrounded to form an opening for welding and assembly with the end cover 211.

[0081] The shell 212 of the battery cell 20 may be, but is not limited to, a cylindrical shell 212, a rectangular shell 212, or a shell 212 of other configurations. For example, when the shell 212 is a cylindrical shell 212, the cylindrical shell 212 includes an annular side wall, the lower plastic layer 24 and the insulating protective layer 23 can be connected to form a sealed connection section 25, and the sealed connection section 25 is arranged around the adapter 26 so that the sealed connection section 25 can separate the adapter 26 and the annular side wall; or, when the shell 212 is a rectangular shell 212, the rectangular shell 212 includes four side walls connected in sequence, the lower plastic layer 24 and the insulating protective layer 23 can be connected to form four sealed connection sections 25, each sealed connection The segments 25 are respectively formed between the adapter plate 26 and the side wall of the corresponding side, so that each sealing connection segment 25 can separate the adapter plate 26 from the side wall of the corresponding side, as shown in Figure 8; or, when the shell 212 is a rectangular shell 212, the rectangular shell 212 includes four side walls connected in sequence, the lower plastic layer 24 and the insulating protective layer 23 can be connected to form a sealing connection segment 25, and the sealing connection segment 25 is arranged in an annular manner on the adapter plate 26, so that the sealing connection segment 25 can be arranged in an annular manner on the adapter plate 26 and separate it from the four side walls, as shown in Figure 9.

[0082] With such a configuration, a sealed connection section 25 is formed between the adapter plate 26 and each side wall of the shell 212 via the lower plastic layer 24 and the insulating protective layer 23, thereby improving the creepage distance between the adapter plate 26 and each side wall of the shell 212, that is, the breakdown voltage between the adapter plate 26 and any side surface of the shell 212 is improved, and the high-voltage breakdown resistance of the shell 212 is effectively improved.

[0083] According to some embodiments of the present application, referring to FIG. 4 to FIG. 8 , the adapter piece 26 has an outer edge portion 263 , and the sealing connection section 25 is configured to block the shortest path from the outer edge portion 263 to the side wall.

[0084] The outer edge portion 263 of the adapter plate 26 refers to a side surface of the adapter plate 26 along its thickness direction.

[0085] The shortest path from the outer edge 263 to the side wall refers to the path formed by any point on the outer edge 263 along a direction perpendicular to the side wall and reaching the side wall. The length of the shortest path is the distance between the point on the outer edge 263 and the side wall.

[0086] The sealing connection section 25 can block the shortest path from the outer edge 263 to the side wall, which means that any point on the outer edge 263 along the direction perpendicular to one of the side walls and the path formed by reaching the side wall needs to pass through the sealing connection section 25 between the side wall and the adapter 26. Therefore, the sealing connection section 25 can effectively block the creepage between the adapter 26 and the side wall, so that the creepage distance is increased, thereby the breakdown voltage between the adapter 26 and any side surface of the shell 212 is improved, and the high-voltage breakdown resistance of the shell 212 is effectively improved.

[0087] It can be understood that the shortest path from the outer edge portion 263 to any side wall can be blocked by the sealing connection section 25 provided between the side wall and the adapter piece 26 .

[0088] In this arrangement, the sealing connection section 25 can block the shortest path from the outer edge 263 to the side wall, and the creepage distance between any point on the outer edge 263 and the side wall on either side can be increased, thereby increasing the breakdown voltage between the adapter 26 and any side wall of the shell 212, and effectively improving the high-voltage breakdown resistance of the shell 212.

[0089] It should be understood that the electrode assembly 22 includes a pole ear 22a, and the adapter plate 26 can be connected to the pole ear 22a at one end and connected to the pole arranged on the end cover 211 at the other end; at this time, the outer edge 263 of the adapter plate 26 is a circle of side wall surface of the adapter plate 26 wrapped around its own thickness direction.

[0090] Alternatively, the adapter plate 26 may include a first adapter portion 261 and a second adapter portion 262, the first adapter portion 261 being arranged between the pole ear 22a and the end cover 211, and the first adapter portion 261 being used to connect the pole arranged on the end cover 211; the pole ear 22a can extend between the first adapter portion 261 and the second adapter portion 262, and be used to connect with the second adapter portion 262; at this time, the outer edge portion 263 of the adapter plate 26 refers to a circle of side wall surface of the first adapter portion 261 wrapped around its own thickness direction, as shown in Figures 5 and 7.

[0091] The first adapter portion 261 and the second adapter portion 262 may be, but are not limited to, sheet structures, block structures, etc. The first adapter portion 261 and the second adapter portion 262 may be welded together, or may be integrally formed. The second adapter portion 262 may be connected to the tab 22a by welding.

[0092] The tab 22a is bent to fit the second transition portion 262 to achieve connection with the second transition portion 262; optionally, the tab 22a can be bent to form a connecting cavity 221 for insertion of the second transition portion 262, thereby achieving a reliable connection between the tab 22a and the second transition portion 262.

[0093] According to some embodiments of the present application, referring to FIG. 4 to FIG. 7 and FIG. 9 , the sealing connection section 25 is annular and wound around the adapter piece 26 .

[0094] It can be understood that the sealing connection section 25 is annular, that is, the lower plastic layer 24 and the insulating protective layer 23 are connected around the adapter 26, and the sealing connection section 25 formed by the connection between the lower plastic layer 24 and the insulating protective layer 23 can surround the adapter 26, effectively improving the creepage distance between the adapter 26 and the shell 212.

[0095] In this way, the sealing connection section 25 is arranged around the adapter plate 26, that is, the sealing connection section 25 can fully separate the adapter plate 26 and the shell 212, effectively improving the breakdown voltage between the adapter plate 26 and the shell 212, and the high-voltage breakdown resistance of the shell 212 is effectively improved.

[0096] According to some embodiments of the present application, referring to FIG. 4 and FIG. 5 , there is a gap between the adapter piece 26 and the sealing connection section 25 .

[0097] It can be understood that when the adapter plate 26 includes the first adapter portion 261 and the second adapter portion 262 , the gap between the adapter plate 26 and the sealing connection section 25 can be formed between the first adapter portion 261 and the sealing connection section 25 .

[0098] In this way, the sealing connection section 25 and the adapter piece 26 are arranged at intervals, that is, there is a gap between the connection between the lower plastic layer 24 and the insulating protective layer 23 and the adapter piece 26, and there is an operating space between the sealing connection section 25 and the adapter piece 26, thereby effectively improving the assembly convenience between the lower plastic layer 24, the insulating protective layer 23 and the adapter piece 26, etc., and at the same time reducing the interference effect between the sealing connection section 25 and the adapter piece 26.

[0099] According to some embodiments of the present application, referring to FIG. 4 and FIG. 5 , the gap width between the adapter piece 26 and the sealing connection section 25 is M, 0<M≤50 mm (hereinafter “mm” is used instead of millimeters).

[0100] It can be understood that in this embodiment, the gap width M between the adapter plate 26 and the sealing connection section 25 can specifically be the gap width between the first adapter portion 261 of the adapter plate 26 and the sealing connection section 25 on the corresponding side, as shown in Figure 5.

[0101] In this way, the gap width between the adapter plate 26 and the sealing connection section 25 is set to be greater than 0 and less than or equal to 50 mm. The sealing connection section 25 can form a gap with the adapter plate 26, effectively insulating and protecting the adapter plate 26, so as to achieve the purpose of increasing the creepage distance between the adapter plate 26 and the shell 212 and improving the high-voltage breakdown resistance of the adapter plate 26.

[0102] According to some embodiments of the present application, referring to FIG. 4 and FIG. 5 , the width of the gap between the adapter piece 26 and the sealing connection section 25 is M, and 3 mm ≤ M ≤ 10 mm.

[0103] With this setting, the gap width between the adapter plate 26 and the sealing connection section 25 is optimized to 3 mm to 10 mm, so as to further reduce the interference effect between the sealing connection section 25 and the adapter plate 26, while increasing the creepage distance between the adapter plate 26 and the shell 212, and improving the high-voltage breakdown resistance of the adapter plate 26.

[0104] According to some embodiments of the present application, referring to FIG. 4 and FIG. 5 , the sealing connection section 25 has a sealing width N, 0<N≤3 mm.

[0105] The sealing width of the sealing connection section 25 refers to the width of the connection between the lower plastic layer 24 and the insulating protective layer 23. Optionally, when the insulating protective layer 23 is connected to the side of the lower plastic layer 24 to form the sealing connection section 25, the sealing width of the sealing connection section 25 is specifically the width along the thickness direction of the lower plastic layer 24.

[0106] In this way, the sealing width of the sealing connection section 25 is set to be greater than 0 and less than or equal to 3 mm, so that the connection between the lower plastic layer 24 and the insulating protective layer 23 has a certain sealing width to ensure the insulating protection performance of the sealing connection section 25.

[0107] According to some embodiments of the present application, referring to FIG. 4 and FIG. 5 , the sealing connection section 25 has a sealing width N, 1 mm ≤ N ≤ 3 mm.

[0108] With this configuration, the width of the sealing connection section 25 is optimized to 1 mm to 3 mm, so that the sealing connection section 25 has the required insulation protection.

[0109] According to some embodiments of the present application, please refer to Figures 4 to 7, the insulating protective layer 23 includes a first insulating portion 231 and a second insulating portion 232, and a sealing fold 233 is provided between the first insulating portion 231 and the second insulating portion 232. The first insulating portion 231 and / or the second insulating portion 232 is configured to be able to be bent around the sealing fold 233.

[0110] It can be understood that the first insulating portion 231 and the second insulating portion 232 are different parts of the insulating protective layer 23. The first insulating portion 231 can be used to cover the side of the electrode assembly 22 and separate the side wall of the shell 212 from the side of the electrode assembly 22; the second insulating portion 232 can be used to cover the end surface of the electrode assembly 22, for example, it can cover the end surface away from the end cover 211, and separate the corresponding end side of the inner wall of the shell 212 from the end surface of the electrode assembly 22.

[0111] The sealing fold 233 is a structure between the first insulating portion 231 and the second insulating portion 232 and is used to fold the first insulating portion 231 or the second insulating portion 232. It is understood that the first insulating portion 231 or the second insulating portion 232 can be folded around the sealing fold 233 so that the first insulating portion 231 and the second insulating portion 232 can be folded to form an angle, so that the first insulating portion 231 and the second insulating portion 232 can be simultaneously covered on different sides of the electrode assembly 22.

[0112] The sealing fold 233 is a mark that does not penetrate the insulating protective layer 23 and is used to improve folding ease. Optionally, the sealing fold 233 can be a continuous groove formed between the first insulating portion 231 and the second insulating portion 232; or the sealing fold 233 can be a discontinuous groove structure formed between the first insulating portion 231 and the second insulating portion 232.

[0113] The first insulating part 231 is used to cover the side of the electrode assembly 22, and the second insulating part 232 is used to cover the end face of the electrode assembly 22 away from the end cover 211. At the same time, the insulating protective layer 23 and the lower plastic layer 24 are connected to form a sealed connection section 25, so as to fully separate the electrode assembly 22 from the outer shell 21, which can effectively increase the creepage distance between the electrode assembly 22 and the outer shell 21, thereby improving the high-voltage breakdown resistance of the outer shell 21.

[0114] With such a configuration, the first insulating portion 231 can be used to insulate and protect the side of the electrode assembly 22, and the second insulating portion 232 can be used to insulate and protect the bottom of the electrode assembly 22 after being bent around the sealing fold 233, thereby effectively improving the insulating protection effect of the insulating protective layer 23 on the electrode assembly 22.

[0115] For example, in some specific embodiments, the battery cell 20 includes a shell 212, an end cap 211, an electrode assembly 22 and an insulating protective film. The electrode assembly 22 is arranged in the accommodating cavity 21a of the shell 212, and the tabs of the electrode assembly 22 are electrically connected to the poles of the end cap 211 through the adapter 26; the surface of the electrode assembly 22 is covered with an insulating protective film, and the insulating protective film can completely cover the side of the electrode assembly 22 and the end face away from the end cap 211, and the insulating protective film can also extend in the direction of the end cap 211 until the insulating protective film and the lower plastic provided on the inner wall of the end cap 211 are connected. The insulating protective film can be arranged around the side of the lower plastic layer 24, and the insulating protective film is connected to the lower plastic layer 24 by full hot melting to form a sealed connection section 25. Specifically, a sealed connection section 25 is formed between the adapter 26 and the side wall of each side of the shell 212, so that the creepage distance between the adapter 26 and the electrode assembly 22 and the shell 212 can be improved, thereby achieving the purpose of increasing the breakdown voltage between the shell 21 and the electrode assembly 22, and can effectively improve the high-voltage breakdown resistance of the shell 21, thereby reducing the probability of combustion or explosion of the battery cell 20.

[0116] According to some embodiments of the present application, referring to Figures 2 to 4, the present application also provides a battery 100 including the above-mentioned battery cell 20. The battery 100 uses any of the battery cells 20 described in the above embodiments, which will not be described in detail here.

[0117] According to some embodiments of the present application, please continue to refer to Figures 1 and 2. The present application also provides an electric device, including the battery 100 as described above. The electric device can be any electric device described in the above embodiments, such as a vehicle 1000, which will not be repeated here.

[0118] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A battery cell, characterized in that: include: A housing having a receiving cavity; an electrode assembly, wherein the electrode assembly is disposed in the accommodating cavity; as well as An insulating protective layer is coated on the electrode assembly.

2. The battery cell according to claim 1, characterized in that: The shell includes an end cover and a shell, the shell is formed with the accommodating cavity with an opening, and the end cover is arranged at the opening; a lower plastic layer is arranged on the inner surface of the end cover, and the lower plastic layer is at least partially connected to the insulating protective layer to form a sealed connection section.

3. The battery cell according to claim 2, characterized in that: The battery cell further includes a switching plate, which is electrically connected to the electrode assembly, and the sealing connection section is provided between at least a portion of the switching plate and the shell.

4. The battery cell according to claim 3, characterized in that: The shell includes a plurality of side walls, and the sealing connection section is provided between the adapter plate and each of the side walls.

5. The battery cell according to claim 4, characterized in that: The adapter plate has an outer edge portion, and the sealing connection section is configured to block the shortest path from the outer edge portion to the side wall.

6. The battery cell according to any one of claims 3 to 5, characterized in that: The sealing connection section is annular and is wound around the adapter plate.

7. The battery cell according to any one of claims 3 to 6, characterized in that: A gap is provided between the adapter plate and the sealing connection section.

8. The battery cell according to claim 7, characterized in that: The gap width between the adapter plate and the sealing connection section is M, 0<M≤50mm.

9. The battery cell according to claim 8, characterized in that: The width of the gap between the adapter plate and the sealing connection section is M, 3mm≤M≤10mm.

10. The battery cell according to any one of claims 2 to 9, characterized in that: The sealing connection section has a sealing width N, 0<N≤3mm.

11. The battery cell according to claim 10, characterized in that: The sealed connection section has a sealing width N, 1 mm ≤ N ≤ 3 mm.

12. The battery cell according to any one of claims 1 to 11, characterized in that: The insulating protective layer includes a first insulating portion and a second insulating portion, a sealing fold is provided between the first insulating portion and the second insulating portion, and the first insulating portion and / or the second insulating portion are configured to be able to be bent around the sealing fold.

13. A battery, characterized in that: The battery comprises the battery cell according to any one of claims 1 to 12.

14. An electrical equipment, characterized in that: The electric device comprises the battery as claimed in claim 13.

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