Battery cell, battery, and electrical apparatus

Abstract

A battery cell (20), a battery, and an electrical apparatus, relating to the field of batteries. The battery cell (20) comprises: a casing (21), the casing (21) comprising a first wall (211) and an electrode terminal (212), the electrode terminal (212) being disposed on the first wall (211); an electrode assembly (22) provided in the casing (21), the electrode assembly (22) comprising an electrode connecting member (221), and the electrode connecting member (221) being electrically connected to the electrode terminal (212); and a high-temperature-resistant insulating layer (23), which is at least partially disposed between the first wall (211) and the electrode connecting member (221), so as to insulate and isolate the first wall (211) from the electrode connecting member (221). The battery cell (20) reduces the risk of thermal runaway.

Description

Battery cells, batteries and electrical devices

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on February 2, 2024, with application number 202420264406.X, and invention name “Battery Cell, Battery and Electrical Device”, the entire contents of which are incorporated by reference into this application. Technical Field

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

[0003] Energy conservation and emission reduction are key to the sustainable development of the automotive industry. Electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of the sustainable development of the automotive industry. For electric vehicles, battery technology is a key factor in their development.

[0004] Power batteries generally include battery cells. How to reduce the risk of thermal runaway of battery cells is an urgent problem that needs to be solved in battery technology.

[0005] Summary of the Invention

[0006] In view of this, embodiments of the present application provide a battery cell, a battery, and an electrical device, which can reduce the risk of thermal runaway of the battery cell.

[0007] An embodiment of the first aspect of the present application provides a battery cell, comprising:

[0008] a housing comprising a first wall and an electrode terminal, wherein the electrode terminal is disposed on the first wall;

[0009] an electrode assembly disposed in the housing, the electrode assembly comprising an electrode connector electrically connected to the electrode terminal; and

[0010] A high temperature resistant insulating layer is at least partially disposed between the first wall and the electrode connector to insulate and separate the first wall from the electrode connector.

[0011] The battery cell provided in the embodiments of the present application includes a housing, an electrode assembly, and a high-temperature resistant insulating layer. The housing includes a first wall and an electrode terminal provided on the first wall. The electrode assembly includes an electrode connector. The high-temperature resistant insulating layer is provided between the first wall and the electrode connector. The high-temperature resistant insulating layer has high-temperature resistance and insulation properties. During the battery cell cycle, the temperature inside the battery cell may gradually increase. The high-temperature resistant insulating layer can maintain good insulation performance in a high-temperature environment, reducing the risk of a short circuit between the housing and the electrode connector of the battery cell, and improving the insulation performance of the battery cell in a high-temperature environment. The embodiments provided in the present application can limit thermal runaway of the battery cell before the battery thermal runaway occurs, reducing the risk of thermal runaway and improving the safety and reliability of the battery cell.

[0012] In some embodiments, the electrode connector includes a tab and a transition piece, the transition piece includes a terminal connection portion and a tab connection portion connected to each other, the terminal connection portion is connected to the electrode terminal, and the tab connection portion is connected to the tab;

[0013] The high temperature resistant insulating layer includes a protective glue provided between the adapter plate and the first wall. Along the thickness direction of the first wall, the projection of the tab connection portion and the projection of the tab are located within the projection range of the protective glue.

[0014] By adopting the above technical solution, the protective glue covers the tabs and adapters, and the protective glue is not easy to melt, which can significantly reduce the risk of short circuit caused by direct contact between the adapter and / or tabs and the shell, thereby reducing the risk of thermal runaway caused by short circuit.

[0015] In some embodiments, in the adapter sheet, there are multiple tab connection parts, and the multiple tab connection parts are arranged along the width direction of the adapter sheet, and the terminal connection part is arranged between two adjacent tab connection parts; the protective glue includes multiple films, and the multiple films are arranged one-to-one corresponding to the multiple tab connection parts.

[0016] By adopting the above technical solution, multiple films are arranged at intervals, which reduces the overall size of the high-temperature resistant insulation layer. Each film can be easily attached to the adapter, so that the attachment method of the high-temperature resistant insulation layer is simple and easy to implement.

[0017] In some embodiments, the length of the film is greater than or equal to the length of the adapter, and the width of the film is greater than or equal to the width of the tab connecting portion.

[0018] The film that meets the above-mentioned size conditions can cover the tab connection part of the adapter, effectively separate the adapter and the shell, and reduce the risk of short circuit caused by contact between the tab connection part and the shell.

[0019] In some embodiments, the tab includes a plurality of stacked tab sheets; along the length direction of the adapter sheet, the difference between the length of the film and the width of the tab sheet is 12 mm-14 mm.

[0020] In some embodiments, the width of the film satisfies:

[0021] W3≥[H+(W1-W2)]*2;

[0022] Wherein W1 is the width of the tab connection portion, W2 is the width of the overlapping area between the tab connection portion and the tab, W3 is the width of the film, and H is the height of the tab.

[0023] By adopting the above technical solution, part of the film is attached to the electrode connector, and the other part is bent and attached to the side of the electrode assembly. Not only is the adhesion effect more firm, but the film can also play an insulating role between the side of the electrode assembly and the outer shell; and the film can cover the pole ear connection part and the pole ear of the adapter along the width direction, and the insulation effect is better.

[0024] In some embodiments, the width of the film satisfies:

[0025] W3=[H+(W1-W2)+2mm]*2.

[0026] By adopting the above technical solution, within the allowable range of process tolerance, the film can cover the tab connection part and the tab of the adapter along the width direction, further improving the insulation reliability.

[0027] In some embodiments, the difference between the length of the film and the length of the adapter sheet is 1 mm and -3 mm; and / or,

[0028] The difference between the width of the film and the width of the tab connecting portion is 10 mm to 15 mm.

[0029] By adopting the above technical solution, the size of the film is reasonable, which can cover the tab connection part and the tab of the adapter along the width and length directions, while avoiding excessive size to waste cost and occupy volume.

[0030] In some embodiments, the protective glue has a thickness of 0.1 mm to 0.5 mm.

[0031] By setting the thickness of the protective glue to meet the above range, the protective glue has good high temperature resistance and insulation performance, and the protective glue will not occupy too much space in the shell due to excessive thickness.

[0032] In some embodiments, the thickness of the protective adhesive is 0.1 mm to 0.3 mm. In this way, the protective adhesive also has good bending performance and is convenient for attachment to the electrode assembly.

[0033] In some embodiments, the melting point of the protective glue is 320°C to 500°C.

[0034] The protective glue provided in the embodiment of the present application has a relatively high melting point, which can reduce the risk of the protective glue melting due to the excessive temperature of the electrode assembly causing a short circuit between the electrode connector and the shell, thereby reducing the risk of thermal runaway.

[0035] In some embodiments, the melting point of the protective glue is greater than 350° C. and less than or equal to 500° C.

[0036] In some embodiments, the protective adhesive is PI tape or Teflon tape.

[0037] By adopting the above technical solution, the protective glue has good high temperature resistance and insulation performance and has good chemical stability, water resistance, moisture resistance, aging resistance, corrosion resistance and other advantages, and is suitable for lithium battery systems.

[0038] In some embodiments, the housing includes an end cap and a shell, the end cap forming the first wall and covering the shell, and a plastic part is provided on a side of the end cap facing the shell, the plastic part being used to separate the end cap and the electrode assembly;

[0039] The high-temperature resistant insulating layer includes an insulating coating located between the end cover and the plastic component, and the heat-resistant temperature of the insulating coating is greater than the melting point of the plastic component.

[0040] In the embodiment of the present application, an insulating coating is provided between the end cap and the plastic part, which can reduce the risk of the plastic part melting in a high-temperature environment and causing the electrode connector to directly contact the end cap, that is, reduce the risk of a short circuit between the electrode connector and the outer shell, thereby reducing the risk of thermal runaway caused by an internal short circuit in the battery cell, and improving the safety and reliability of the battery cell.

[0041] In some embodiments, the insulating coating is provided on a surface of the end cap facing the housing and does not cover the electrode terminal.

[0042] The above-mentioned insulating coating is provided on the end cover, is simple to manufacture and has uniform film formation, and can play a good insulating role between the end cover and the electrode assembly.

[0043] In some embodiments, along the thickness direction of the first wall, the projection of the electrode connector is located within the projection range of the insulating coating.

[0044] In some embodiments, the insulating coating has a heat-resistant temperature of 400°C to 1000°C.

[0045] The insulating coating has a high heat resistance temperature. When the temperature of the battery cell gradually increases and when thermal runaway occurs, the insulating coating can maintain its chemical properties for a long time. The insulating coating can separate the end cover and the electrode assembly. The above insulating coating can be applied to lithium battery systems.

[0046] In some embodiments, the material of the insulating coating includes an organic polymer or a metal oxide, the organic polymer includes one of polytetrafluoroethylene, polyethylene, polypropylene, polyethylene terephthalate, and polyimide, and the metal oxide includes one of aluminum oxide, aluminum hydroxide, titanium dioxide, and magnesium oxide.

[0047] By adopting the above technical solution, the insulating coating made of the above material has good insulation performance and high temperature resistance.

[0048] In some embodiments, the thickness of the insulating coating is 0.05 mm to 0.15 mm.

[0049] By adopting the above technical solution, the thickness of the insulating coating will not significantly increase the thickness of the end cover and can play a better protective role.

[0050] In some embodiments, the battery cell further includes a high-temperature resistant protective film, which covers at least a portion of the housing, and the melting point of the high-temperature resistant protective film is greater than or equal to 500°C.

[0051] The melting point of the high-temperature resistant protective film is greater than or equal to 500°C. When the electrode assembly is charged and discharged with a large current or thermal runaway occurs, causing the temperature to rise, the high-temperature resistant protective film on the surface of the electrode assembly will not melt, which can reduce the heat transfer between the battery cells in the module, lower the temperature of adjacent battery cells, reduce the risk of heat spread, and further improve safety.

[0052] In some embodiments, the material of the high temperature resistant protective film includes PI glue.

[0053] Since PI glue has good heat resistance, the high temperature resistant protective film has significantly improved resistance performance compared to traditional blue film.

[0054] In some embodiments, the thickness of the high temperature resistant protective film is 0.15 mm to 0.25 mm.

[0055] By adopting the above technical solution, the high-temperature resistant protective film can not only provide good protection for the battery cells, but also avoid occupying too much space in the module.

[0056] An embodiment of the second aspect of the present application provides a battery, comprising the battery cell provided in the first aspect.

[0057] An embodiment of the third aspect of the present application provides an electrical device, comprising the battery provided in the second aspect.

[0058] 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

[0059] 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 conventional 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 labor.

[0060] FIG1 is a schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0061] FIG2 is a schematic structural diagram of a battery provided in some embodiments of the present application;

[0062] FIG3 is a schematic structural diagram of a battery cell provided in some embodiments of the present application;

[0063] FIG4 is a schematic structural diagram of an electrode assembly provided in some embodiments of the present application;

[0064] FIG5 is a schematic structural diagram of an electrode assembly and a high-temperature resistant insulating layer provided in some embodiments of the present application;

[0065] FIG6 is a schematic structural diagram of a high-temperature resistant insulation layer on an end cap provided in some embodiments of the present application;

[0066] FIG7 is a schematic structural diagram of a first wall provided in some embodiments of the present application.

[0067] The meanings of the marks in the figure are: 1000, vehicle; 100, battery; 200, controller; 300, motor; 10, casing; 11, first part; 12, second part; 20, battery cell; 21, outer shell; 211, first wall; 2113, electrode lead-out hole; 212, electrode terminal; 213, shell; 214, plastic part; 215, top patch; 22, electrode assembly; 221, electrode connector; 2211, tab; 22111, tab sheet; 2211a, positive tab; 2211b, negative tab; 2212, adapter; 2212a, terminal connection part; 2212b, tab connection part; 222, main body; 223, insulating sheet; 23, high temperature resistant insulating layer; 231, protective glue; 2311, film; 232, insulating coating; 24, high temperature resistant protective film. Modes for Carrying Out the Invention

[0068] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0069] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art 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" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0070] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0071] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0072] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0073] 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).

[0074] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They 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 device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the embodiments of the present application.

[0075] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0076] Lithium battery safety has long been a research focus. The primary safety risk stems from uncontrolled heat generation caused by internal or external short circuits within the battery cell, resulting from overcharging, abuse, external heating, physical collisions, and internal defects. This can ultimately lead to heat spread within the battery cell, and even fire and explosion, resulting in accidents. Thermal runaway is most often caused by internal short circuits. After a localized internal short circuit occurs, the battery cell rapidly discharges, causing the temperature to rise, leading to thermal contraction or melting of the separator, further exacerbating the short circuit hazard. This leads to a sharp rise in battery temperature, accompanied by chain reactions such as electrolyte and material decomposition, ultimately culminating in battery fire and explosion.

[0077] In view of this, the present application provides a battery cell that can reduce the risk of internal short circuit in the battery cell, thereby reducing the risk of thermal runaway in the battery cell, and reducing the risk of heat spread between battery cells. The battery cell provided in the embodiment of the present application includes a shell, an electrode assembly and a high-temperature resistant insulating layer, the first wall of the shell is provided with an electrode terminal, the electrode assembly is provided with an electrode connector, and the high-temperature resistant insulating layer is provided between the first wall and the electrode connector. The high-temperature resistant insulating layer has high-temperature resistance and insulation properties. When the temperature inside the battery cell rises, the high-temperature resistant insulating layer can still isolate the shell and the electrode connector, reducing the risk of short circuit between the shell and the electrode connector, thereby reducing the risk of thermal runaway due to internal short circuit in the battery cell, and reducing the risk of combustion or even explosion of the battery cell.

[0078] The battery cells provided in the embodiments of the present application can be used in electrical devices that use batteries as power sources. The electrical devices may include, but are not limited to, mobile phones, tablets, laptop computers, electric toys, power tools, battery-powered vehicles, electric vehicles, ships, spacecraft, and the like. Among them, electric toys may include fixed or mobile electric toys, such as game consoles, electric vehicle toys, electric ship toys, and electric airplane toys, and the like. Spacecraft may include airplanes, rockets, space shuttles, and spacecraft, and the like.

[0079] 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.

[0080] 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.

[0081] 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.

[0082] Please refer to Figure 2, which is an exploded view of a battery 100 provided in some embodiments of the present application. In some embodiments, the battery 100 includes a housing 10 and a battery cell 20, wherein the battery cell 20 is accommodated in the housing 10.

[0083] The box body 10 is used to provide a storage space for the battery cells, and the box body 10 can adopt a variety of structures. In some embodiments, the box body 10 may include a first part 11 and a second part 12, and the first part 11 and the second part 12 cover each other, and the first part 11 and the second part 12 jointly define a storage space for accommodating the battery cells. The second part 12 can be a hollow structure with one end open, and the first part 11 can be a plate-like structure, and the first part 11 covers the open side of the second part 12, so that the first part 11 and the second part 12 jointly define a storage space; the first part 11 and the second part 12 can also be hollow structures with one side open, and the open side of the first part 11 covers the open side of the second part 12. Of course, the box body 10 formed by the first part 11 and the second part 12 can be a variety of shapes, such as a cylinder, a cuboid, etc.

[0084] 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 single unit 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.

[0085] 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.

[0086] The first embodiment of the present application provides a battery cell 20. Referring to Figures 3 to 5 , the battery cell 20 includes a housing 21, an electrode assembly 22, and a high-temperature-resistant insulating layer 23. The housing 21 includes a first wall 211 and an electrode terminal 212, with the electrode terminal 212 disposed on the first wall 211. The electrode assembly 22 is disposed within the housing 21 and includes an electrode connector 221 electrically connected to the electrode terminal 212. The high-temperature-resistant insulating layer 23 is disposed between the first wall 211 and the electrode connector 221 to insulate and separate the first wall 211 from the electrode connector 221.

[0087] The outer shell 21 is a component used to create the internal environment of the battery cell 20. The internal environment formed by the outer shell 21 can be used to accommodate the electrode assembly 22, electrolyte, and other components. The outer shell 21 may include a shell 213 with an open end and an end cap disposed on the shell 213. It can also be a one-piece structure. The outer shell 21 can have a variety of shapes and sizes, such as a rectangular parallelepiped, a cylinder, a hexagonal prism, etc. Specifically, the shape of the outer shell 21 can be determined based on the specific shape and size of the electrode assembly 22. The outer shell 21 can be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc. The first wall 211 of the outer shell 21 is provided with an electrode lead-out hole 2113. The first wall 211 with the electrode lead-out hole 2113 can be located on the side, top, or bottom of the outer shell 21. The electrode lead-out hole 2113 is used to mount the electrode terminal 212. The electrode lead-out hole 2113 can be a circular through-hole or a through-hole of other shapes.

[0088] The electrode assembly 22 is the component within the battery cell 20 where the electrochemical reaction occurs. One or more electrode assemblies 22 may be contained within the housing 21. The electrode assembly 22 is primarily composed of a positive electrode sheet and a negative electrode sheet wound or stacked, typically with a separator between them. The portions of the positive and negative electrode sheets containing active material constitute the main body of the electrode assembly 22, while the portions of the positive and negative electrode sheets without active material each constitute the tabs 2211.

[0089] The electrode connector 221 in the embodiment of the present application includes at least a tab 2211. In some embodiments, the electrode connector 221 may further include other components electrically connected between the tab 2211 and the electrode terminal 212. For example, the electrode connector 221 includes the tab 2211 and a transition piece 2212, and the transition piece 2212 is welded to the tab 2211 and the electrode terminal 212. During the charge and discharge process of the battery cell 20, the positive electrode active material and the negative electrode active material react with the electrolyte, and the electrode connector 221 connects to the electrode terminal 212 to form a current loop.

[0090] The electrode terminal 212 is inserted into the electrode lead-out hole 2113 and is used to electrically connect to external electrical components and to electrically connect to the electrode connector 221. The electrode terminal 212 in the embodiment of the present application can be a negative electrode terminal or a positive electrode terminal.

[0091] The high-temperature-resistant insulating layer 23 is disposed between the first wall 211 and the electrode connector 221 and is used to insulate the first wall 211 from the electrode connector 221. The high-temperature-resistant insulating layer 23 has both high-temperature resistance and insulation properties. Its high heat resistance allows the insulating properties of the high-temperature-resistant insulating layer 23 to remain effective for a long time in high-temperature environments. This makes the insulating properties of the high-temperature-resistant insulating layer 23 less susceptible to failure due to the high temperature environment of the battery cell 20. This reduces the risk of a short circuit between the outer shell 21 of the battery cell 20 and the electrode connector 221, thereby improving the insulating properties of the battery cell 20 in high-temperature environments.

[0092] The high-temperature resistant insulating layer 23 can be arranged on the surface of the first wall 211 facing the electrode assembly 22, or on the surface of the electrode connector 221 facing the first wall 211; the material of the high-temperature resistant insulating layer 23 can be an inorganic material, an organic material, or a mixture of inorganic and organic materials. It should be noted that no matter what material the high-temperature resistant insulating layer 23 is made of, the high-temperature resistant insulating layer 23 can adopt the high-temperature resistant and insulating materials commonly used in this field.

[0093] The battery cell 20 provided in the embodiment of the present application includes an outer shell 21, an electrode assembly 22 and a high-temperature resistant insulating layer 23. The outer shell 21 includes a first wall 211 and an electrode terminal 212 is provided on the first wall 211. The electrode assembly 22 has an electrode connector 221. The high-temperature resistant insulating layer is provided between the first wall 211 and the electrode connector 221. The high-temperature resistant insulating layer has high-temperature resistance and insulation properties. During the circulation of the battery cell 20, the temperature inside the battery cell 20 may gradually increase. The high-temperature resistant insulating layer can maintain good insulation performance in a high-temperature environment, reduce the risk of overlap short circuit between the outer shell 21 and the electrode connector 221 of the battery cell 20, improve the insulation performance of the battery cell 20 in a high-temperature environment, thereby reducing the risk of thermal runaway, improving the safety and reliability of the battery cell 20, and reducing the risk of heat spread between the battery cells 20.

[0094] In some embodiments, the heat-resistant temperature of the high-temperature resistant insulation layer is greater than 300°C.

[0095] Heat-resistant temperature is a term in the field of materials science, which refers to the temperature at which a substance can maintain its performance unchanged at high temperatures. The heat-resistant temperature of different materials varies due to factors such as their composition, structure and preparation process. At high temperatures, some materials will undergo chemical reactions, decomposition, oxidation or melting, and lose their original properties. Therefore, heat-resistant temperature is one of the important indicators to measure the performance of materials at high temperatures. The heat-resistant temperature of the high-temperature resistant insulating layer provided in the embodiment of the present application is greater than 300°C. When the battery cell 20 gradually heats up during the cycle, the high-temperature resistant insulating layer can maintain insulation performance for a longer period of time, thereby reducing the risk of short circuit between the electrode assembly 22 and the outer casing 21, and improving the safety of the battery cell 20.

[0096] Referring to Figures 3 to 5, in some embodiments, the electrode connector 221 includes a tab 2211 and a transfer plate 2212. The transfer plate 2212 is connected between the tab 2211 and the electrode terminal 212. The transfer plate 2212 includes a terminal connection portion 2212a connected to the electrode terminal 212 and a tab connection portion 2212b connected to the tab 2211. The high-temperature resistant insulating layer 23 includes a protective adhesive 231 disposed between the transfer plate 2212 and the first wall 211. Along the thickness direction of the first wall 211, the projections of the tab connection portion 2212b and the tab 2211 are located within the projection range of the protective adhesive 231. The tab connection portion 2212b and the tab 2211 are covered by the protective adhesive 231, while the terminal connection portion 2212a is not covered by the protective adhesive 231.

[0097] Specifically, the electrode assembly 22 includes a main body 222 and an electrode connector 221. The electrode connector 221 includes a tab 2211 and a transition piece 2212. The tab 2211 extends from one end of the main body close to the first wall 211. The main body 222 is the core part of the electrode assembly 22 for realizing the charge and discharge functions. The tab 2211 is used to lead the current generated by the main body. The main body includes a positive current collecting portion of the positive current collector, a positive active material layer, a negative current collecting portion of the negative current collector, a negative active material layer, and a separator. There can be two tabs 2211, and the two tabs 2211 are respectively a positive tab 2211a and a negative tab 2211b. The positive tab 2211a and the negative tab 2211b can be led out from the same end of the electrode assembly 22, or respectively from opposite ends of the electrode assembly 22.

[0098] There can be one or more electrode assemblies 22 housed in the housing 21. For example, in FIG3 , there are two electrode assemblies 22, each of which has a positive tab 2211a and a negative tab 2211b, one adapter 2212 connecting the two positive tabs 2211a, and another adapter 2212 connecting the two negative tabs 2211b.

[0099] The adapter plate 2212 is disposed on a side of the tab 2211 near the first wall 211. The adapter plate 2212 is used to electrically connect the electrode terminal 212 and the tab 2211. The adapter plate 2212 includes a terminal connecting portion 2212a connected to the electrode terminal 212 and a tab connecting portion 2212b connected to the tab 2211. The tab connecting portion 2212b is covered with a protective adhesive 231 to reduce the risk of contact between the tab 2211 and the tab connecting portion 2212b and the housing 21. The terminal connecting portion 2212a is not covered by the protective adhesive 231, so that the high-temperature-resistant insulating layer 23 does not affect the connection between the adapter plate 2212 and the electrode terminal 212.

[0100] The tab 2211 is also covered by the protective adhesive 231. The portion of the tab 2211 covered by the tab connection portion 2212b is necessarily covered by the protective adhesive 231. The portion of the tab 2211 not covered by the protective adhesive 231 may also be covered by the protective adhesive 231. It is understood that the protective adhesive 231 may completely cover the tab 2211 to reduce the risk of short circuits.

[0101] To conduct the current generated by the main body of the electrode assembly 22, the adapter 2212 is conductive. A protective adhesive 231 is disposed between the adapter 2212 and the first wall 211. The high-temperature-resistant insulating layer 23 can be fixed to the adapter 2212, the first wall 211, or both. The protective adhesive 231 can be provided on both the adapter 2212 and the first wall 211. The protective adhesive 231 is heat-resistant and can be made of a variety of materials, such as PI adhesive.

[0102] By adopting the above-mentioned technical solution, the high-temperature resistant insulating layer 23 includes a protective glue 231 arranged between the adapter plate 2212 and the first wall 211. The protective glue 231 covers the pole ear 2211 and the adapter plate 2212. When the temperature of the electrode assembly 22 is too high, the protective glue 231 is not easy to melt, which can significantly reduce the risk of short circuit caused by direct contact between the adapter plate 2212 and / or the pole ear 2211, thereby reducing the risk of thermal runaway caused by short circuit.

[0103] In some embodiments, the adapter 2212 includes multiple tab connection portions 2212b, which are arranged along the width of the adapter 2212. The terminal connection portion 2212a is located between two adjacent tab connection portions 2212b. The protective adhesive 231 includes multiple adhesive sheets 2311, which are arranged in a one-to-one correspondence with the multiple tab connection portions 2212b.

[0104] Please refer to Figure 5. There are multiple tabs 2211. The adapter 2212 is provided with two tab connecting portions 2212b along its width direction. The terminal connecting portion 2212a is provided between the two tab connecting portions 2212b. Each tab connecting portion 2212b is used to connect a corresponding tab 2211. The protective glue 231 includes a plurality of spaced-apart films 2311. The films 2311 are arranged in one-to-one correspondence with the tab connecting portions 2212b and with the tabs 2211, so as to cover the corresponding tab connecting portions 2212b and the corresponding tabs 2211.

[0105] Exemplarily, four tabs 2211 are provided within the housing 21. The four tabs 2211 include two positive tabs 2211a and two negative tabs 2211b. The number of electrode terminals 212 and the number of adapters 2212 are both two. The two tab connecting portions 2212b of one adapter 2212 are respectively connected to the two positive tabs 2211a, and the two tab connecting portions 2212b of the other adapter 2212 are respectively connected to the two negative tabs 2211b. The high-temperature-resistant insulating layer 23 includes four films 2311, which are arranged in a one-to-one correspondence with the four tab connecting portions 2212b and the four tabs 2211.

[0106] By adopting the above technical solution, multiple films 2311 are arranged at intervals, which reduces the overall size of the high-temperature resistant insulation layer 23. Each film 2311 can be easily attached to the adapter plate 2212, so that the attachment method of the high-temperature resistant insulation layer 23 is simple and easy to implement.

[0107] It can be understood that in other embodiments, adjacent films 2311 may also be connected to each other. For example, the protective glue 231 is an integral structure that covers two adapter plates 2212 at the same time, and the protective glue 231 is provided with a through hole for exposing the terminal connection part 2212a; for example, the protective glue 231 includes two spaced films 2311, each film 2311 covers one adapter plate 2212 and is provided with a through hole for exposing the terminal connection part 2212a.

[0108] In some embodiments, the length of the film 2311 is greater than or equal to the length of the adapter 2212, and the width of the film 2311 is greater than or equal to the width of the tab connection portion 2212b. The film 2311 can cover the tab connection portion 2212b and the edge of the main body 222. The portion of the film 2311 that extends beyond the tab can be bent and attached to the main body 222.

[0109] The film 2311 meeting the above size conditions can cover the tab connection portion 2212b of the adapter 2212, effectively separating the adapter 2212 from the housing 21, and reducing the risk of short circuit caused by contact between the tab connection portion 2212b and the housing 21.

[0110] 3 to 5, in some embodiments, the tab 2211 includes a plurality of stacked tab sheets 22111. L1 in FIG4 represents the width of the tab sheet 22111, and L2 in FIG5 represents the length of the film 2311. Along the length direction of the adapter sheet 2212, the difference between the length L2 of the film 2311 and the width L1 of the tab sheet 22111 is 12 mm to 14 mm, i.e.

[0111] 12mm≤L2-L1≤14mm.

[0112] Since each pole ear 2211 includes multiple stacked pole ear sheets 22111, the multiple pole ear sheets 22111 may be misaligned. Considering the tolerance, the length of the film 2311 meets the above-mentioned size requirements, so that the film 2311 can cover each pole ear sheet 22111. The film 2311 can isolate the adapter sheet 2212 / pole ear 22111 and the first wall 211 along the length direction of the adapter sheet 2212.

[0113] Referring to Figures 3 to 5 , one end of the tab 2211 extends from the main body 222, and the other end of the tab 2211 is connected to the adapter plate 2212. The tab 2211 and the tab connecting portion 2212b are stacked. The tab 2211 can be located on a side of the tab connecting portion 2212b that is closer to the first wall 211, or on a side of the tab connecting portion 2212b that is away from the first wall 211. To improve insulation, a film 2311 can cover opposite ends of the tab 2211. The tab connection portion 2212b has an area that overlaps with the tab 2211, and the tab connection portion 2212b also has an area that does not overlap with the tab 2211. In order to improve the insulation effect, the film 2311 can cover the tab connection portion 2212b. In this way, the film 2311 can effectively isolate the tab 2211 and the adapter 2212 from short-circuiting with the housing 21 in areas other than the terminal connection portion 2212a.

[0114] In some embodiments, the width of the film 2311 satisfies:

[0115] W3≥[H+(W1-W2)]*2;

[0116] Wherein W1 is the width of the tab connection portion 2212b, W2 is the width of the overlapping area between the tab connection portion 2212b and the tab 2211, W3 is the width of the film 2311, and H is the height of the tab 2211. The difference between W1 and W2 represents the width of the area where the tab connection portion 2212b does not overlap with the tab 2211, that is, the width between the terminal connection portion 2212a and the tab 2211. The area where the tab connection portion 2212b does not overlap with the tab 2211 can be covered by the film 2311. Furthermore, "H+(W1-W2)" represents the sum of the height of the tab 2211 and the width of the area where the tab connection portion 2212b does not overlap with the tab 2211, which can also be understood as the distance from the terminal connection portion 2212a to the root of the tab 2211. At the same time, half of the film 2311 along its width is attached to the tab 2111 and the adapter 2212, and the other half is attached to the side of the electrode assembly 22. Therefore, W3 ≥ [H + (W1 - W2)] * 2. In addition, W4 in Figure 4 is the width of the adapter 2212.

[0117] The width W1 of the tab connection portion 2212b is the distance from the terminal connection portion 2212a to the edge of the adapter 2212 in the width direction. When the terminal connection portion 2212a is a boss, W1 is the distance from the boss to the edge of the adapter 2212 in the width direction.

[0118] By adopting the above technical solution, a part of the film 2311 is attached to the electrode connector 221, and the other part is bent and attached to the side of the electrode assembly 22. Not only is the adhesion effect more firm, but the film 2311 can also play an insulating role between the side of the electrode assembly 22 and the outer shell 21; and, the film 2311 can cover the pole ear connection part 2212b and the pole ear 2211 of the adapter 2212 along its width direction, and the insulation effect is better.

[0119] In some embodiments, the width of the film satisfies:

[0120] W3=[H+(W1-W2)+2mm]*2.

[0121] The 2 mm margin is set to account for process tolerances. Even if there are deviations in the attachment position of the film 2311 or the width of the film 2311, the film 2311 can still separate the electrode connector 221 and the first wall 211. By meeting the above technical solution, the insulation reliability of the film 2311 is further improved.

[0122] In some embodiments, the thickness of the protective adhesive 231 is 0.1 mm to 0.5 mm. For example, the thickness of the protective adhesive 231 can be 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, etc. By setting the thickness of the protective adhesive 231 to meet the above range, the protective adhesive 231 has good high temperature resistance and insulation performance, and the protective adhesive 231 does not occupy too much space within the housing 21 due to excessive thickness.

[0123] In some embodiments, the thickness of the protective adhesive 231 is 0.1 mm to 0.3 mm. In this way, the protective adhesive 231 also has good bending properties and is convenient for attachment to the electrode assembly 22 .

[0124] In some embodiments, the protective adhesive 231 is a polyimide (PI) tape or a Teflon tape.

[0125] PI tape refers to a high-temperature-resistant tape made from polyimide (PI). It typically uses a polyimide film as a backing material with an adhesive layer. PI tape exhibits properties such as high and low temperature resistance, acid and alkali resistance, solvent resistance, and electrical insulation. In some embodiments, the melting point of PI tape can reach 375°C. The melting point is the temperature at which a solid material transforms (melts) from a solid to a liquid.

[0126] Teflon tape refers to high-temperature-resistant tape made from Teflon. Typically, Teflon tape uses a fiberglass base, coated with a Teflon solution, dried, and then re-coated with silicone adhesive. Teflon tape offers high strength, high-temperature resistance, a smooth surface, and chemical resistance. It also provides excellent electrical insulation, stability, and durability. In some embodiments, the melting point of Teflon tape can reach 375°C.

[0127] By adopting the above technical solution, the protective adhesive 231 is made of PI tape or Teflon tape. The protective adhesive 231 has good high temperature resistance and insulation performance and has good chemical stability, water resistance, moisture resistance, aging resistance, corrosion resistance and other advantages, which are suitable for lithium battery systems. When the temperature of the electrode assembly 22 is too high, the protective adhesive 231 is not easy to melt, which can reduce the risk of short circuit caused by direct contact between the adapter 2212 and / or the tab 2211 and the housing 21, thereby reducing the risk of thermal runaway caused by short circuit. It is understood that the protective adhesive 231 can also be made of other high temperature resistant and insulating materials.

[0128] In some embodiments, the melting point of the protective glue 231 is 320° C. to 500° C.

[0129] Taking PI tape as an example, the melting point of PI tape is related to the density of the PI and can range from 200°C to 500°C. To improve the temperature resistance of protective adhesive 231, the PI adhesive selected in this embodiment can have a melting point of 320°C to 500°C, such as 320°C, 375°C, 400°C, or 500°C. Taking Teflon tape as an example, the melting point of Teflon tape can reach 327°C, 375°C, or the like. It is understood that protective adhesive 231 can also be made of other materials or a mixed material containing PI or Teflon, with the melting point of protective adhesive 231 also within the range of 320°C to 500°C.

[0130] The protective glue 231 provided in the embodiment of the present application has a relatively high melting point, which can reduce the risk of the protective glue 231 melting due to the excessive temperature of the electrode assembly 22 causing a short circuit between the electrode connector 221 and the housing 21, thereby reducing the risk of thermal runaway.

[0131] In some embodiments, the melting point of the protective glue 231 is greater than 350° C. and less than or equal to 500° C. For example, the melting point of the protective glue 231 may be 360° C., 400° C., 450° C., 500° C., etc.

[0132] By adopting the above technical solution, the protective glue 231 used in the embodiment of the present application has a high melting point. Even if the temperature inside the battery cell 20 rises or thermal runaway occurs, the protective glue 231 will not melt, thereby reducing the risk of short circuit between the electrode connector 221 and the first wall 211 and reducing the risk of heat spread.

[0133] Please refer to Figures 3, 6 and 7. In some embodiments, the shell 21 includes an end cover and a shell 213. The end cover constitutes a first wall 211 and covers the shell 213. A plastic part 214 is provided on the side of the end cover facing the shell 213. The plastic part 214 is used to separate the end cover and the electrode assembly 22; the high-temperature resistant insulating layer 23 includes an insulating coating 232 located between the end cover and the plastic part 214. The heat-resistant temperature of the insulating coating 232 is greater than the melting point of the plastic part 214.

[0134] For example, in FIG3 , the housing 213 is a rectangular parallelepiped structure, and the end cap is a plate-like structure, which covers the opening at the top of the housing 213. In other embodiments, the housing 213 may also be cylindrical or have other shapes, with the end cap adapted to the shape of the housing 213. The plastic part 214 is fixed to the side of the end cap facing the housing 213. The plastic part 214 has insulating properties and can isolate the end cap from the electrode assembly 22. It is understood that because the electrode connector 221 needs to be connected to the electrode terminal 212, the plastic part 214 is provided with a through hole that avoids the electrode terminal 212.

[0135] Optionally, the insulating coating 232 is attached to the surface of the end cap by spraying, coating, etc. In other embodiments, the insulating coating 232 can be attached to the surface of the plastic part 214 by spraying, coating, etc. The insulating coating 232 has good heat resistance, and the heat resistance temperature of the insulating coating 232 is greater than the melting point of the plastic part 214. When the electrode assembly 22 is charged and discharged with a large current or thermal runaway occurs, causing the temperature to rise, the plastic part 214 may be melted. At this time, the insulating coating 232 can still isolate the electrode connector 221 and the end cap, reducing the risk of short circuit between the electrode connector 221 and the end cap. Among them, the electrode connector 221 includes a tab 2211 and a transfer plate 2212. The insulating coating 232 can isolate the transfer plate 2212 and the end cap, and also isolate the tab 2211 and the end cap.

[0136] In the embodiment of the present application, an insulating coating 232 is provided between the end cap and the plastic part 214, which can reduce the risk of the plastic part 214 melting in a high temperature environment and causing the electrode connector 221 to directly contact the end cap, that is, reduce the risk of a short circuit between the electrode connector 221 and the outer shell 21, thereby reducing the risk of thermal runaway caused by an internal short circuit in the battery cell 20, and improving the safety and reliability of the battery cell 20.

[0137] 3 and 6 , in some embodiments, the insulating coating 232 is disposed on the surface of the end cap facing the electrode assembly 22 and does not cover the electrode terminal 212 .

[0138] Before the plastic part 214 is secured to the end cap, a high-temperature resistant insulating material is first formed on the surface of the end cap by spraying, coating, physical vapor deposition (PVD), chemical vapor deposition (CVD), or other methods to form an insulating coating 232. The insulating coating 232 avoids the electrode lead-out hole 2113. Since the electrode terminal 212 needs to be connected to the electrode connector 221, the insulating coating 232 does not need to cover the electrode terminal 212. The insulating coating 232 is provided on the end cap, is simple to manufacture, and forms a uniform film, which can provide good insulation between the end cap and the electrode assembly 22.

[0139] The insulating coating 232 is made of an organic polymer or a metal oxide. The organic polymer includes one of polytetrafluoroethylene, polyethylene, polypropylene, polyethylene terephthalate, and polyimide. The metal oxide includes one of aluminum oxide, aluminum hydroxide, titanium dioxide, and magnesium oxide. The insulating coating 232 made of the above materials has excellent insulation performance and high-temperature resistance. It is understood that the insulating coating 232 may also be made of other materials with both insulation and high-temperature resistance.

[0140] In some embodiments, along the thickness direction of the first wall 211 , the projection of the electrode connector 221 is located within the projection range of the insulating coating 232 .

[0141] In this way, the electrode connector 221 can be completely covered by the insulating coating 232 . It is understood that at least a portion of the electrode connector 221 needs to be covered by the insulating coating 232 .

[0142] In some embodiments, the heat-resistant temperature of the insulating coating 232 is 400° C. to 1000° C.

[0143] Since the insulating coating 232 can be made of a variety of high-temperature resistant and insulating materials, the heat-resistant temperature of the insulating coating 232 varies depending on the material. The heat-resistant temperature range of the insulating coating 232 is relatively large. For example, the heat-resistant temperature of the insulating coating 232 can be 400°C, 500°C, 600°C, 700°C, 800°C, 900°C, 1000°C, etc.

[0144] Taking the LFP module target cell as an example, the temperature of thermal runaway is 240°C to 350°C. The temperature of the electrode assembly 22 rises, causing the plastic part 214 to melt. At this time, the heat resistance temperature of the insulating coating 232 is greater than or equal to 400°C, so the insulating coating 232 can still maintain its insulation performance. LFP is a lithium-ion battery, whose full name is Lithium Iron Phosphate Battery.

[0145] The insulating coating 232 has a high heat resistance temperature. When the temperature of the battery cell 20 gradually increases and when thermal runaway occurs, the insulating coating 232 can maintain its chemical properties for a long time. The insulating coating 232 can separate the end cover and the electrode assembly 22. The above-mentioned insulating coating 232 can be applied to lithium battery systems.

[0146] The thickness of the insulating coating 232 can be 0.05 mm to 0.15 mm. This thickness does not significantly increase the thickness of the end cap and provides adequate protection. For example, the thickness of the insulating coating 232 is 0.1 mm. It is understood that the thickness of the insulating coating 232 can also be adjusted based on the requirements of the battery cell 20. For example, the thickness of the insulating coating 232 can range from 0.02 mm to 0.3 mm.

[0147] 3 , in some embodiments, the battery cell 20 further includes a high-temperature resistant protective film 24 , which covers at least a portion of the housing 21 . The melting point of the high-temperature resistant protective film 24 is greater than or equal to 500° C.

[0148] The high-temperature protective film 24 is made of a high-temperature resistant insulating material and can separate adjacent battery cells 20, preventing the impact of various failures of a single battery cell 20 on other battery cells 20. The high-temperature protective film 24 is coated on the outer shell 21, wherein the high-temperature protective film 24 can surround the entire surface of the outer shell 21 or cover at least a portion of the surface of the outer shell 21. In some embodiments, the high-temperature protective film 24 is coated on both the end cap and the shell 213. The battery cell 20 also includes a top patch 215 fixed to the side of the end cap facing away from the shell 213, and the high-temperature protective film 24 is coated on the outside of the top patch 215.

[0149] The melting point of the high-temperature resistant protective film 24 is greater than or equal to 500°C. When the electrode assembly 22 is charged and discharged with a large current or thermal runaway occurs, causing the temperature to rise, the high-temperature resistant protective film 24 on the surface of the electrode assembly 22 will not be melted, which can reduce the heat transfer between the battery cells 20 in the module, reduce the temperature of adjacent battery cells 20, reduce the risk of heat spread, and further improve safety. In some related technologies, a blue film is wrapped on the outer shell 21. The blue film is an insulating film used to insulate and protect the battery cells 20 to prevent the outer shells 21 of adjacent battery cells from contacting or the outer shells 21 of the battery cells 20 from contacting the battery box, causing a short circuit. The high-temperature resistant protective film 24 provided in the embodiment of the present application replaces the traditional blue film. Compared with the blue film, the high-temperature resistant protective film 24 can withstand higher temperatures and reduce heat transfer between adjacent battery cells 20.

[0150] In some embodiments, the material of the high temperature resistant protective film 24 includes PI glue.

[0151] PI glue is an adhesive primarily composed of a polyimide resin, a solvent, and a curing agent. The proportion of PI glue can be adjusted based on requirements. For example, the heat-resistant protective film 24 is made of a 50% PI glue mixture. The heat-resistant protective film 24 is a composite film that also includes epoxy resin and other ingredients.

[0152] Since PI glue has good heat resistance, the high temperature resistant protective film 24 significantly improves the resistance performance compared to the traditional blue film.

[0153] In some embodiments, the thickness of the high-temperature-resistant protective film 24 is 0.15 mm to 0.25 mm. For example, the thickness of the high-temperature-resistant protective film 24 is 0.15 mm, 0.2 mm, 0.25 mm, etc. By adopting the above technical solution, the high-temperature-resistant protective film 24 can not only effectively protect the battery cells 20, but also avoid occupying excessive space within the module.

[0154] Referring to Figures 3 to 7 , a battery cell 20 includes a housing 21, an electrode assembly 22, and a high-temperature-resistant insulating layer 23. The housing 21 has a first wall 211 on which an electrode terminal 212 is disposed. The electrode assembly 22 is disposed within the housing 21 and is provided with an electrode connector 221, which is electrically connected to the electrode terminal 212. The high-temperature-resistant insulating layer 23 is disposed between the first wall 211 and the electrode connector 221. The high-temperature-resistant insulating layer 23 includes at least one of a protective adhesive 231 and an insulating coating 232. The protective adhesive 231 is disposed between the adapter 2212 and the first wall 211. The tab connection portion 2212b and the tab 2211 are covered by the protective adhesive 231, while the terminal connection portion 2212a is not covered by the protective adhesive 231. The insulating coating 232 is located between the end cap and the plastic component 214. The battery cell 20 also includes a high-temperature-resistant protective film 24, which covers at least a portion of the housing 21. The battery cell 20 further includes an insulating sheet 223 covering the outside of the electrode assembly 22 for protecting and insulating the electrode assembly 22 , thereby preventing the electrode assembly 22 from contacting the housing 21 and causing a short circuit during operation.

[0155] The battery cell 20 provided in the embodiment of the present application reduces the risk of thermal runaway caused by a short circuit between the electrode assembly 22 and the housing 21 , and reduces the risk of combustion or even explosion of the battery cell 20 .

[0156] A second aspect of the present application provides a battery 100 , comprising the battery cell 20 provided in the first aspect.

[0157] A third aspect of the present application provides an electrical device, comprising the battery 100 provided in the second aspect, wherein the battery 100 is used to provide electrical energy to the electrical device.

[0158] The power-consuming device may be any of the aforementioned devices or systems using batteries.

[0159] It should be noted that, unless there is any conflict, the features in the embodiments of this application can be combined with each other.

[0160] 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 make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included in the scope of protection of the present application.

Claims

1. A battery cell, wherein: include: a housing comprising a first wall and an electrode terminal, wherein the electrode terminal is disposed on the first wall; an electrode assembly disposed in the housing, the electrode assembly comprising an electrode connector electrically connected to the electrode terminal; as well as A high temperature resistant insulating layer is at least partially disposed between the first wall and the electrode connector to insulate and separate the first wall from the electrode connector.

2. The battery cell according to claim 1, wherein: The electrode connector includes a tab and a transition piece, the transition piece includes a terminal connection portion and a tab connection portion connected to each other, the terminal connection portion is connected to the electrode terminal, and the tab connection portion is connected to the tab; The high temperature resistant insulating layer includes a protective glue arranged between the adapter plate and the first wall. Along the thickness direction of the first wall, the projection of the tab connection portion and the projection of the tab are at least partially located within the projection range of the protective glue.

3. The battery cell according to claim 2, wherein: In the adapter, there are a plurality of tab connection portions, the plurality of tab connection portions are arranged along the width direction of the adapter, and the terminal connection portion is provided between two adjacent tab connection portions; The protective glue includes a plurality of films, and the plurality of films are arranged in a one-to-one correspondence with the plurality of tab connecting portions.

4. The battery cell according to claim 3, wherein: The length of the film is greater than or equal to the length of the adapter, and the width of the film is greater than or equal to the width of the tab connecting portion.

5. The battery cell according to claim 4, wherein: The tab comprises a plurality of tab sheets stacked in layers; Along the length direction of the adapter sheet, the difference between the length of the film and the width of the tab sheet is 12 mm to 14 mm.

6. The battery cell according to claim 4 or 5, wherein: The width of the film satisfies: W3≥[H+(W1-W2)]*2; Wherein W1 is the width of the tab connection portion, W2 is the width of the overlapping area between the tab connection portion and the tab, W3 is the width of the film, and H is the height of the tab.

7. The battery cell according to claim 6, wherein: The width of the film satisfies: W3 = [H + (W1 - W2) + 2 mm] * 2.

8. The battery cell according to any one of claims 2 to 7, wherein: The thickness of the protective glue is 0.1mm-0.5mm.

9. The battery cell according to claim 8, wherein: The thickness of the protective glue is 0.1mm-0.3mm.

10. The battery cell according to any one of claims 2 to 9, wherein: The melting point of the protective glue is 320°C to 500°C.

11. The battery cell according to claim 10, wherein: The melting point of the protective glue is greater than 350° C. and less than or equal to 500° C.

12. The battery cell according to any one of claims 2 to 11, wherein: The protective adhesive is PI tape or Teflon tape.

13. The battery cell according to any one of claims 1 to 12, wherein: The housing includes an end cap and a shell, the end cap forming the first wall and covering the shell, and a plastic part is provided on the side of the end cap facing the shell, the plastic part is used to separate the end cap and the electrode assembly; The high-temperature resistant insulating layer includes an insulating coating located between the end cover and the plastic component, and the heat-resistant temperature of the insulating coating is greater than the melting point of the plastic component.

14. The battery cell according to claim 13, wherein: The insulating coating is provided on a surface of the end cover facing the housing and does not cover the electrode terminal.

15. The battery cell according to claim 13, wherein: Along the thickness direction of the first wall, the projection of the electrode connector is located within the projection range of the insulating coating.

16. The battery cell according to any one of claims 13 to 15, wherein: The heat-resistant temperature of the insulating coating is 400°C to 1000°C.

17. The battery cell according to any one of claims 13 to 16, wherein: The material of the insulating coating includes an organic polymer or a metal oxide, the organic polymer includes one of polytetrafluoroethylene, polyethylene, polypropylene, polyethylene terephthalate, and polyimide, and the metal oxide includes one of aluminum oxide, aluminum hydroxide, titanium dioxide, and magnesium oxide.

18. The battery cell according to any one of claims 13 to 17, wherein: The thickness of the insulating coating is 0.05 mm to 0.15 mm.

19. The battery cell according to any one of claims 1 to 18, wherein: The battery cell further includes a high-temperature resistant protective film, which covers at least a portion of the shell, and the melting point of the high-temperature resistant protective film is greater than or equal to 500°C.

20. The battery cell according to claim 19, wherein The material of the high temperature resistant protective film includes PI glue.

21. The battery cell according to claim 19 or 20, wherein: The thickness of the high temperature resistant protective film is 0.15 mm to 0.25 mm.

22. A battery, wherein: The invention comprises the battery cell according to any one of claims 1 to 21.

23. An electrical device, wherein: The battery according to claim 22 is used to provide electrical energy to the electrical device.

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