Battery monomer, battery and electric device

Abstract

The utility model relates to the field of batteries, and provides a battery monomer, a battery and a power utilization device, the battery monomer comprises a shell, the shell comprises a first wall and an electrode terminal, and the electrode terminal is arranged on the first wall; the electrode assembly is arranged in the shell, the electrode assembly comprises an electrode connecting piece, and the electrode connecting piece is electrically connected with the electrode terminal; and the high-temperature-resistant insulating layer is at least partially arranged between the first wall and the electrode connecting piece so as to insulate and separate the first wall from the electrode connecting piece. According to the battery cell provided by the embodiment of the invention, the risk of thermal runaway is reduced.

Description

Technical Field

[0001] 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

[0002] Energy conservation and emission reduction are the key to the sustainable development of the automobile industry. Electric vehicles have become an important part of the sustainable development of the automobile industry due to their advantages of energy conservation and environmental protection. For electric vehicles, battery technology is an important factor related to their development.

[0003] Power batteries generally include battery cells. How to reduce the risk of thermal runaway of battery cells is an urgent problem to be solved in battery technology. Utility Model Content

[0004] In view of this, the 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.

[0005] The embodiment of the first aspect of the present application provides a battery cell, comprising:

[0006] A housing, comprising a first wall and an electrode terminal, wherein the electrode terminal is disposed on the first wall;

[0007] an electrode assembly disposed in the housing, the electrode assembly comprising an electrode connector electrically connected to the electrode terminal; and

[0008] The 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.

[0009] 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 shell includes a first wall and an electrode terminal arranged on the first wall, the electrode assembly includes an electrode connector, the high temperature resistant insulating layer is arranged 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 process, 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, reduce the risk of overlapping short circuit between the shell of the battery cell and the electrode connector, and improve the insulation performance of the battery cell in a high temperature environment. The embodiment provided in the present application can limit the thermal runaway of the battery cell before the battery thermal runaway, reduce the risk of thermal runaway, and improve the safety and reliability of the battery cell.

[0010] In some embodiments, the electrode connector includes a tab and a transfer sheet, the transfer sheet 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;

[0011] The high temperature resistant insulating layer includes a protective glue disposed between the adapter plate and the first wall. Along the thickness direction of the first wall, the projection of the pole ear connecting portion and the projection of the pole ear are located within the projection range of the protective glue.

[0012] By adopting the above technical solution, the protective glue covers the tabs and the adapter, 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 the tabs and the shell, thereby reducing the risk of thermal runaway caused by short circuit.

[0013] In some embodiments, in the adapter sheet, the number of the tab connection parts is multiple, the multiple tab connection parts are arranged along the width direction of the adapter sheet, and the terminal connection part is provided between two adjacent tab connection parts;

[0014] The protective glue comprises a plurality of films, and the plurality of films are arranged in one-to-one correspondence with the plurality of tab connecting parts.

[0015] 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 conveniently attached to the adapter sheet, so that the attachment method of the high temperature resistant insulation layer is simple and easy to implement.

[0016] In some embodiments, the length of the film is greater than or equal to the length of the adapter sheet, and the width of the film is greater than or equal to the width of the tab connecting portion.

[0017] The film that meets the above-mentioned size conditions can cover the tab connection portion of the adapter, effectively separate the adapter from the housing, and reduce the risk of short circuit caused by contact between the tab connection portion and the housing.

[0018] 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.

[0019] In some embodiments, the width of the film satisfies:

[0020] W3≥[H+(W1-W2)]*2;

[0021] Wherein W1 is the width of the pole lug connection portion, W2 is the width of the overlapping area between the pole lug connection portion and the pole lug, W3 is the width of the film, and H is the height of the pole lug.

[0022] 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.

[0023] In some embodiments, the width of the film satisfies:

[0024] W3 = [H + (W1-W2) + 2mm] * 2.

[0025] 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 reliability of insulation.

[0026] 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,

[0027] The difference between the width of the film and the width of the tab connection portion is 10 mm to 15 mm.

[0028] By adopting the above technical solution, the size of the film is reasonable, which can not only cover the pole ear connection part and the pole ear of the adapter along the width and length directions, but also avoid being too large in size to waste costs and occupy volume.

[0029] In some embodiments, the thickness of the protective glue is 0.1 mm-0.5 mm.

[0030] 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.

[0031] In some embodiments, the thickness of the protective glue is 0.1 mm-0.3 mm. In this way, the protective glue also has good bending performance and is convenient to be attached to the electrode assembly.

[0032] In some embodiments, the melting point of the protective glue is 320°C to 500°C.

[0033] 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 overly high temperature of the electrode assembly causing a short circuit between the electrode connector and the shell, thereby reducing the risk of thermal runaway.

[0034] In some embodiments, the melting point of the protective glue is greater than 350° C. and less than or equal to 500° C.

[0035] In some embodiments, the protective adhesive is PI tape or Teflon tape.

[0036] 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.

[0037] In some embodiments, the housing includes an end cap and a shell, the end cap constitutes the first wall and covers the shell, and a plastic part is provided on a side of the end cap facing the shell, and the plastic part is used to separate the end cap and the electrode assembly;

[0038] The high temperature resistant insulating layer comprises an insulating coating located between the end cover and the plastic part, and the heat resistant temperature of the insulating coating is greater than the melting point of the plastic part.

[0039] 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.

[0040] In some embodiments, the insulating coating is disposed on a surface of the end cap facing the housing and does not cover the electrode terminal.

[0041] The above-mentioned insulating coating is arranged 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.

[0042] 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.

[0043] In some embodiments, the heat-resistant temperature of the insulating coating is 400°C to 1000°C.

[0044] 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 chemical properties for a long time. The insulating coating can separate the end cover and the electrode assembly. The above insulating coating can be applicable to lithium battery systems.

[0045] In some embodiments, the material of the insulating coating includes an organic polymer or a metal oxide, the organic polymer includes polytetrafluoroethylene, polyethylene, polypropylene, polyethylene terephthalate, and one of polyimide, and the metal oxide includes one of aluminum oxide, aluminum hydroxide, titanium dioxide, and magnesium oxide.

[0046] By adopting the above technical solution, the insulating coating made of the above material has good insulating performance and high temperature resistance.

[0047] In some embodiments, the thickness of the insulating coating is 0.05 mm to 0.15 mm.

[0048] 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.

[0049] In some embodiments, the battery cell further includes a high temperature resistant protective film, the high temperature resistant protective film covers at least a portion of the outer shell, and the melting point of the high temperature resistant protective film is greater than or equal to 500°C.

[0050] 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, reduce the temperature of adjacent battery cells, reduce the risk of heat spread, and further improve safety.

[0051] In some embodiments, the material of the high temperature resistant protective film includes PI glue.

[0052] Since PI glue has good heat resistance, the high temperature resistant protective film significantly improves the resistance performance compared to the traditional blue film.

[0053] In some embodiments, the thickness of the high temperature resistant protective film is 0.15 mm to 0.25 mm.

[0054] 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.

[0055] An embodiment of the second aspect of the present application provides a battery, comprising a battery cell as provided in the first aspect.

[0056] An embodiment of the third aspect of the present application provides an electrical device, comprising the battery provided in the second aspect.

[0057] 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

[0058] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or conventional technical descriptions will be briefly introduced below. 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 creative labor.

[0059] Figure 1 is a schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0060] Figure 2 is a schematic diagram of the structure of a battery provided in some embodiments of the present application;

[0061] Figure 3 is a schematic diagram of the structure of a battery cell provided in some embodiments of the present application;

[0062] Figure 4 is a schematic diagram of the structure of an electrode assembly provided in some embodiments of the present application;

[0063] Figure 5 is a schematic diagram of the structure of an electrode assembly and a high temperature resistant insulating layer provided in some embodiments of the present application;

[0064] Figure 6 It is a schematic diagram of the structure of a high temperature resistant insulation layer on an end cover provided in some embodiments of the present application;

[0065] Figure 7 It is a schematic diagram of the structure of the first wall provided in some embodiments of the present application.

[0066] The meanings of the marks in the figure are:

[0067] 1000, vehicle; 100, battery; 200, controller; 300, motor;

[0068] 10. Box body; 11. First part; 12. Second part;

[0069] 20. Battery cells;

[0070] 21. Shell; 211. First wall (end cover); 2113. Electrode lead-out hole; 212. Electrode terminal; 213. Shell; 214. Plastic part; 215. Top patch;

[0071] 22, electrode assembly; 221, electrode connector; 2211, pole ear; 22111, pole ear sheet; 2211a, positive pole ear; 2211b, negative pole ear; 2212, adapter; 2212a, terminal connection part; 2212b, pole ear connection part;

[0072] 222, main body; 223, insulating sheet;

[0073] 23. High temperature resistant insulation layer; 231. Protective glue; 2311. Film; 232. Insulation coating;

[0074] 24. High temperature resistant protective film. DETAILED DESCRIPTION

[0075] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0076] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0077] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0078] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0079] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0080] 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).

[0081] In the description of the embodiments of the present application, the orientations or positional relationships indicated by technical terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are 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 referred device or element 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.

[0082] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0083] The safety of lithium batteries has always been a research focus. The safety risks of lithium batteries are mainly caused by uncontrollable heat generation caused by internal / external short circuits in the battery cells due to overcharging, external heating, physical collisions, internal defects, etc., which eventually cause the heat spread of the battery cells, or even fire and explosion, resulting in safety accidents. Most of the causes of thermal runaway are caused by internal short circuits. After a local internal short circuit occurs, the battery cells discharge rapidly, the temperature rises, and the diaphragm shrinks or melts, further exacerbating the short circuit hazard. The battery temperature rises sharply, accompanied by chain reactions such as electrolyte decomposition and material decomposition, and the battery eventually catches fire and explodes.

[0084] 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.

[0085] The battery cell provided in the embodiment of the present application can be used for an electric device that uses the battery as a power source, and the electric device can be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, etc. Among them, the electric toy can include a fixed or mobile electric toy, for example, a game console, an electric car toy, an electric ship toy, an electric airplane toy, etc., and the spacecraft can include an airplane, a rocket, a space shuttle, a spacecraft, etc.

[0086] 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.

[0087] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle 1000 provided for some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000, and the battery 100 may be provided at the bottom, head or tail of the vehicle 1000. The battery 100 may be used to power the vehicle 1000, for example, the battery 100 may be used as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, and 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.

[0088] In some embodiments of the present application, the battery 100 can not only serve as an operating power source for the vehicle 1000, but also serve 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.

[0089] Please refer to Figure 2 , Figure 2 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 .

[0090] The box 10 is used to provide a storage space for the battery cells, and the box 10 can adopt a variety of structures. In some embodiments, the box 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 10 formed by the first part 11 and the second part 12 can be in a variety of shapes, such as a cylinder, a cuboid, etc.

[0091] 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 mixed connection. A mixed connection means that the multiple battery cells 20 are both connected in series and in parallel. The multiple battery cells 20 may be directly connected in series, in parallel, or in a mixed connection, and then the whole formed by the multiple battery cells 20 is accommodated in the box 10; of course, the battery 100 may also be a battery module formed by connecting multiple battery cells 20 in series, in parallel, or in a mixed connection, and then the multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole, and accommodated in the box 10. The battery 100 may also include other structures, for example, the battery 100 may also include a busbar component for realizing electrical connection between the multiple battery cells 20.

[0092] Each battery cell 20 may be a secondary battery or a primary battery, or 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.

[0093] The embodiment of the first aspect of the present application provides a battery cell 20. Figures 3 to 5 The battery cell 20 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. The electrode terminal 212 is arranged on the first wall 211; the electrode assembly 22 is arranged in the outer shell 21, and the electrode assembly 22 includes an electrode connector 221, which is electrically connected to the electrode terminal 212; the high-temperature resistant insulating layer 23 is arranged between the first wall 211 and the electrode connector 221 to insulate and separate the first wall 211 from the electrode connector 221.

[0094] The shell 21 is an element for forming the internal environment of the battery cell 20. The internal environment formed by the shell 21 can be used to accommodate the electrode assembly 22, the electrolyte and other components. The shell 21 may include a shell 213 with an opening at one end and an end cover provided on the shell 213, or may be an integrally formed structure. The shell 21 may be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism shape, etc. Specifically, the shape of the shell 21 may be determined according to the specific shape and size of the electrode assembly 22. The material of the shell 21 may be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc. An electrode lead-out hole 2113 is provided on the first wall 211 of the shell 21, and the first wall 211 having the electrode lead-out hole 2113 may be provided on the side, top or bottom of the shell 21. The electrode lead-out hole 2113 is used to install the electrode terminal 212, and the electrode lead-out hole 2113 may be a circular through hole or a through hole of other shapes.

[0095] The electrode assembly 22 is a component in the battery cell 20 where an electrochemical reaction occurs. The housing 21 may contain one or more electrode assemblies 22. The electrode assembly 22 is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is usually provided between the positive electrode sheet and the negative electrode sheet. The parts of the positive electrode sheet and the negative electrode sheet with active materials constitute the main body of the electrode assembly 22, and the parts of the positive electrode sheet and the negative electrode sheet without active materials each constitute a tab 2211.

[0096] The electrode connector 221 in the embodiment of the present application at least includes a tab 2211. In some embodiments, the electrode connector 221 may also include other elements electrically connected between the tab 2211 and the electrode terminal 212. For example, the electrode connector 221 includes a tab 2211 and a transfer sheet 2212, and the transfer sheet 2212 is respectively 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 the electrode terminal 212 to form a current loop.

[0097] The electrode terminal 212 is inserted into the electrode lead-out hole 2113, and is used to be electrically connected to an external electrical component and to be electrically connected to the electrode connector 221. The electrode terminal 212 in the embodiment of the present application may be a negative electrode terminal or a positive electrode terminal.

[0098] The high temperature resistant insulating layer 23 is provided between the first wall 211 and the electrode connector 221, and is used to isolate the first wall 211 from the electrode connector 221. The high temperature resistant insulating layer 23 has the characteristics of high temperature resistance and insulation, and the heat resistance temperature of the high temperature resistant insulating layer 23 is relatively high, so that the insulation performance of the high temperature resistant insulating layer 23 can be maintained for a long time in a high temperature environment, and the insulation performance of the high temperature resistant insulating layer 23 is not easily invalidated due to the battery cell 20 being in a high temperature environment, reducing the risk of overlapping short circuit between the housing 21 of the battery cell 20 and the electrode connector 221, and improving the insulation performance of the battery cell 20 in a high temperature environment.

[0099] 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 material commonly used in this field.

[0100] 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.

[0101] In some embodiments, the heat-resistant temperature of the high-temperature resistant insulation layer is greater than 300°C.

[0102] Heat resistance 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 resistance 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 resistance temperature is one of the important indicators to measure the performance of materials at high temperatures. The heat resistance 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 cyclic use process, the high temperature resistant insulating layer can maintain the 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.

[0103] Please refer to Figures 3 to 5 In some embodiments, the electrode connector 221 includes a tab 2211 and a transfer sheet 2212, the transfer sheet 2212 is connected between the tab 2211 and the electrode terminal 212, and the transfer sheet 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 glue 231 disposed between the transfer sheet 2212 and the first wall 211, and along the thickness direction of the first wall 211, the projection of the tab connection portion 2212b and the projection of the tab 2211 are located within the projection range of the protective glue 231. The tab connection portion 2212b and the tab 2211 are covered by the protective glue 231, and the terminal connection portion 2212a is not covered by the protective glue 231.

[0104] Specifically, the electrode assembly 22 includes a main body 222 and an electrode connector 221, and the electrode connector 221 includes a pole ear 2211 and a transfer sheet 2212, and the pole ear 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 to realize the charging and discharging function, and the pole ear 2211 is used to lead the current generated by the main body. The main body includes a positive current collecting part of the positive current collector, a positive active material layer, a negative current collecting part of the negative current collector, a negative active material layer and a separator. There can be two pole ears 2211, and the two pole ears 2211 are respectively a positive pole ear 2211a and a negative pole ear 2211b. The positive pole ear 2211a and the negative pole ear 2211b can be led out from the same end of the electrode assembly 22, or they can be led out from the opposite ends of the electrode assembly 22.

[0105] The electrode assembly 22 contained in the housing 21 may be one or more. Figure 3 In the embodiment, there are two electrode assemblies 22, each of which has a positive electrode tab 2211a and a negative electrode tab 2211b, one adapter 2212 connects the two positive electrode tabs 2211a, and the other adapter 2212 connects the two negative electrode tabs 2211b.

[0106] The adapter 2212 is disposed on one side of the tab 2211 close to the first wall 211. The adapter 2212 is used to electrically connect the electrode terminal 212 and the tab 2211. The adapter 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 tab connection portion 2212b is covered by a protective glue 231 to reduce the risk of the tab 2211 and the tab connection portion 2212b contacting the housing 21; the terminal connection portion 2212a is not covered by the protective glue 231, so that the high temperature resistant insulating layer 23 will not affect the connection of the adapter 2212 to the electrode terminal 212.

[0107] The tab 2211 is also covered by the protective glue 231, wherein the portion of the tab 2211 covered by the tab connection portion 2212b is necessarily covered by the protective glue 231; the portion of the tab 2211 not covered by the protective glue 231 may also be covered by the protective glue 231. It is understood that the protective glue 231 may completely cover the tab 2211 to reduce the risk of short circuit.

[0108] In order to lead out the current generated by the main body of the electrode assembly 22, the adapter sheet 2212 has conductivity. The protective glue 231 is provided between the adapter sheet 2212 and the first wall 211, wherein the high temperature resistant insulating layer 23 can be fixed on the adapter sheet 2212, or on the first wall 211, or the protective glue 231 is provided on both the adapter sheet 2212 and the first wall 211. The protective glue 231 is a high temperature resistant protective glue, and its material can be various, such as PI glue.

[0109] 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, and 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 and the outer shell 21, thereby reducing the risk of thermal runaway caused by short circuit.

[0110] In some embodiments, in the adapter 2212, there are multiple tab connection parts 2212b, and the multiple tab connection parts 2212b are arranged along the width direction of the adapter 2212, and the terminal connection part 2212a is arranged between two adjacent tab connection parts 2212b. The protective glue 231 includes multiple films 2311, and the multiple films 2311 are arranged one by one with the multiple tab connection parts 2212b.

[0111] Please refer to Figure 5 , there are multiple pole lugs 2211, the adapter 2212 is provided with two pole lug connecting portions 2212b along its width direction, the terminal connecting portion 2212a is arranged between the two pole lug connecting portions 2212b, and each pole lug connecting portion 2212b is used to connect a corresponding pole lug 2211; the protective glue 231 includes a plurality of spaced-apart films 2311, and the films 2311 are arranged one-to-one with the pole lug connecting portions 2212b and one-to-one with the pole lugs 2211 to cover the corresponding pole lug connecting portions 2212b and the corresponding pole lugs 2211.

[0112] Exemplarily, four tabs 2211 are provided in the housing 21, and 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, and the two tab connections 2212b of one adapter 2212 are respectively connected to the two positive tabs 2211a, and the two tab connections 2212b of another adapter 2212 are respectively connected to the two negative tabs 2211b. The high temperature resistant insulating layer 23 includes four films 2311, and the four films 2311 are arranged in one-to-one correspondence with the four tab connections 2212b and in one-to-one correspondence with the four tabs 2211.

[0113] 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 sheet 2212, so that the attachment method of the high temperature resistant insulation layer 23 is simple and easy to implement.

[0114] 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 a through hole is provided in the protective glue 231 for exposing the terminal connection part 2212a; for another 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.

[0115] 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 film 2311 can cover the edge of the main body 222, and the portion of the film 2311 that exceeds the tab can be bent and attached to the main body 222.

[0116] The film 2311 that meets the above-mentioned size conditions can cover the tab connection portion 2212b of the adapter 2212, effectively separate the adapter 2212 from the housing 21, and reduce the risk of short circuit caused by contact between the tab connection portion 2212b and the housing 21.

[0117] Please refer to Figures 3 to 5 In some embodiments, the tab 2211 includes a plurality of tab sheets 22111 stacked together. Figure 4 L1 in the figure indicates the width of the tab 22111. Figure 5 L2 in the figure represents the length of the film 2311. Along the length direction of the adapter plate 2212, the difference between the length L2 of the film 2311 and the width L1 of the tab plate 22111 is 12 mm to 14 mm, that is,

[0118] 12mm≤L2-L1≤14mm.

[0119] Since each pole ear 2211 includes multiple stacked pole ear sheets 22111, the multiple pole ear sheets 22111 may be misaligned. Taking tolerance into consideration, the length of the film 2311 meets the above-mentioned size requirements, so that the film 2311 can cover each pole ear sheet 22111, and 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.

[0120] Please refer to Figures 3 to 5One end of the tab 2211 is led out from the main body 222, and the other end of the tab 2211 is connected to the adapter 2212, wherein the tab 2211 and the tab connection portion 2212b are stacked, and the tab 2211 can be located on a side of the tab connection portion 2212b close to the first wall 211, or the tab 2211 can also be located on a side of the tab connection portion 2212b away from the first wall 211. In order to improve the insulation effect, the film 2311 can cover the opposite ends of the tab 2211. The pole lug connection portion 2212b has an area overlapping with the pole lug 2211, and the pole lug connection portion 2212b also has an area not overlapping with the pole lug 2211. In order to improve the insulation effect, the film 2311 can cover the pole lug connection portion 2212b. In this way, the film 2311 can effectively isolate the pole lug 2211 and the adapter 2212 from short-circuiting with the housing 21 in areas other than the terminal connection portion 2212a.

[0121] In some embodiments, the width of the film 2311 satisfies:

[0122] W3≥[H+(W1-W2)]*2;

[0123] Wherein W1 is the width of the tab connection portion 2212b, W2 is the width of the overlapping region of 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 region 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, and the region where the tab connection portion 2212b does not overlap with the tab 2211 can be covered by the film 2311; further, "H+(W1-W2)" represents the sum of the height of the tab 2211 and the width of the region where the tab connection portion 2212 does not overlap with the tab 2211, and can also be understood as the distance from the terminal connection portion 2212b to the root of the tab 2211. At the same time, half of the film 2311 along its width direction is attached to the tab 2111 and the adapter 2212, and the other half is attached to the side of the electrode assembly 22, so W3≥[H+(W1-W2)]*2. In addition, Figure 4 W4 in FIG. 2 is the width of the adapter plate 2212 .

[0124] 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 of the adapter 2212.

[0125] 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.

[0126] In some embodiments, the width of the film satisfies:

[0127] W3 = [H + (W1-W2) + 2mm] * 2.

[0128] Among them, 2mm is a margin value set considering process tolerance. When there is a deviation in the attachment position of the film 2311 or a deviation in the width dimension 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.

[0129] In some embodiments, the thickness of the protective glue 231 is 0.1 mm-0.5 mm. For example, the thickness of the protective glue 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 glue 231 to meet the above range, the protective glue 231 has good high temperature resistance and insulation performance, and the protective glue 231 will not occupy too much space in the housing 21 due to excessive thickness.

[0130] In some embodiments, the thickness of the protective glue 231 is 0.1 mm-0.3 mm. Thus, the protective glue 231 also has good bending performance and is convenient to be attached to the electrode assembly 22.

[0131] In some embodiments, the protective adhesive 231 is a polyimide (PI) tape or a Teflon tape.

[0132] PI tape refers to a high temperature resistant tape whose material includes PI. Usually, PI tape uses polyimide film as the base material, and an adhesive layer is provided on the base material. PI tape has the properties of 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, and the melting point is the temperature at which a solid changes its physical state from solid (melts) to liquid.

[0133] Teflon tape refers to a high temperature resistant tape whose material includes Teflon. Usually, Teflon tape uses glass fiber as the base cloth, is coated with Teflon solution and dried to make Teflon glass fiber cloth, and then is coated with silicone adhesive for the second time. Teflon tape has the characteristics of high strength, high temperature resistance, smooth surface, chemical corrosion resistance, etc., and has good electrical insulation performance, good stability and good durability. In some embodiments, the melting point of Teflon tape can reach 375°C.

[0134] By adopting the above technical solution, the protective glue 231 is a PI tape or a Teflon tape. The protective glue 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, and is suitable for lithium battery systems. When the temperature of the electrode assembly 22 is too high, the protective glue 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 can be understood that the protective glue 231 can also be other high temperature resistant and insulating materials.

[0135] In some embodiments, the melting point of the protective glue 231 is 320° C. to 500° C.

[0136] Taking PI tape as an example, the melting point of PI tape is related to the density of PI, and the melting point of PI tape can be 200°C to 500°C. In order to improve the temperature resistance of the protective adhesive 231, the melting point of the PI adhesive selected in the embodiment of the present application can be 320°C to 500°C, such as 320°C, 375°C, 400°C, 500°C, etc. Taking Teflon tape as an example, the melting point of Teflon tape can reach 327°C, 375°C, etc. It can be understood that the protective adhesive 231 can also be other materials or a mixed material including PI or Teflon, and the melting point of the protective adhesive 231 is also in the range of 320°C to 500°C.

[0137] 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 overly high 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.

[0138] 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., and the like.

[0139] By adopting the above technical solution, the protective glue 231 used in the embodiment of the present application has a higher 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.

[0140] Please refer to Figure 3 , Figure 6 and Figure 7 In some embodiments, the housing 21 includes an end cap and a shell 213, the end cap constitutes a first wall 211 and covers the shell 213, a plastic part 214 is provided on the side of the end cap facing the shell 213, and the plastic part 214 is used to separate the end cap and the electrode assembly 22; the high temperature resistant insulating layer 23 includes an insulating coating 232 located between the end cap and the plastic part 214, and the heat resistance temperature of the insulating coating 232 is greater than the melting point of the plastic part 214.

[0141] For example, in Figure 3 In the embodiment, the shell 213 is a rectangular parallelepiped structure, and the end cap is a plate-like structure, and the end cap covers the opening at the top of the shell 213. In other embodiments, the shell 213 may also be cylindrical or in other shapes, and the end cap is adapted to the shape of the shell 213. The plastic part 214 is fixed to the side of the end cap facing the shell 213. The plastic part 214 has an insulating property and can isolate the end cap from the electrode assembly 22. It can be understood that since the electrode connector 221 needs to be connected to the electrode terminal 212, the plastic part 214 is provided with a through hole to avoid the electrode terminal 212.

[0142] 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 pole ear 2211 and a transfer sheet 2212. The insulating coating 232 can isolate the transfer sheet 2212 and the end cap, and also isolates the pole ear 2211 and the end cap.

[0143] 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.

[0144] Please refer to Figure 3 , Figure 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 .

[0145] Before the plastic part 214 is fixed 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), etc. to form an insulating coating 232, and 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 above-mentioned insulating coating 232 is provided on the end cap, which is simple to manufacture and has uniform film formation, and can play a good insulating role between the end cap and the electrode assembly 22.

[0146] The material of the insulating coating 232 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. The insulating coating 232 made of the above materials has good insulation performance and high temperature resistance. It is understood that the insulating coating 232 can also be made of other materials with insulation properties and high temperature resistance.

[0147] 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 .

[0148] In this way, the electrode connector 221 can be completely covered by the insulating coating 232. It can be understood that at least a portion of the electrode connector 221 needs to be covered by the insulating coating 232.

[0149] In some embodiments, the heat-resistant temperature of the insulating coating 232 is 400° C. to 1000° C.

[0150] 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 is different 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.

[0151] Taking the LFP module target cell as an example, the temperature of thermal runaway is 240℃~350℃. The temperature of the electrode assembly 22 rises, which will cause the plastic part 214 to melt. At this time, the heat-resistant temperature of the insulating coating 232 is greater than or equal to 400℃, so the insulating coating 232 can still maintain its insulation performance. LFP is a lithium-ion battery, and its full name is Lithium Iron Phosphate Battery.

[0152] 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 chemical properties for a long time. The insulating coating 232 can separate the end cover and the electrode assembly 22. The above insulating coating 232 can be suitable for lithium battery systems.

[0153] The thickness of the insulating coating 232 may be 0.05 mm to 0.15 mm. In this way, the thickness of the insulating coating 232 does not significantly increase the thickness of the end cap and can provide a good protective effect. For example, the thickness of the insulating coating 232 is 0.1 mm. It is understood that the thickness of the insulating coating 232 may also be adjusted according to the requirements of the battery cell 20. For example, the thickness of the insulating coating 232 may range from 0.02 mm to 0.3 mm.

[0154] Please refer to Figure 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, and the melting point of the high temperature resistant protective film 24 is greater than or equal to 500°C.

[0155] The high temperature resistant protective film 24 is made of high temperature resistant insulating material, which can separate adjacent battery cells 20 and prevent the impact of various faults of a single battery cell 20 on other battery cells 20. The high temperature resistant protective film 24 is coated on the outer shell 21, wherein the high temperature resistant protective film 24 can surround the entire surface of the outer shell 21, and can also cover at least part of the surface of the outer shell 21. In some embodiments, the high temperature resistant protective film 24 is coated on both the end cover and the shell 213. The battery cell 20 also includes a top patch 215 fixed to the side of the end cover away from the shell 213, and the high temperature resistant protective film 24 is coated on the outside of the top patch 215.

[0156] 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 the heat transfer between adjacent battery cells 20.

[0157] In some embodiments, the material of the high temperature resistant protective film 24 includes PI glue.

[0158] PI glue is an adhesive mainly composed of polyimide resin, solvent and curing agent. The proportion of PI glue can be adjusted according to demand. For example, the material of the high temperature resistant protective film 24 is mixed with 50% PI glue. The high temperature resistant protective film 24 is a composite film and also includes ingredients such as epoxy resin.

[0159] 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.

[0160] 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 provide good protection for the battery cell 20, but also avoid occupying too much space in the module.

[0161] Please refer to Figures 3 to 7 The battery cell 20 includes a shell 21, an electrode assembly 22 and a high temperature resistant insulating layer 23. The shell 21 has a first wall 211 and an electrode terminal 212 is provided on the first wall 211. The electrode assembly 22 is arranged in the shell 21. The electrode assembly 22 is provided with an electrode connector 221, and the electrode connector 221 is electrically connected to the electrode terminal 212. The high temperature resistant insulating layer 23 is arranged between the first wall 211 and the electrode connector 221. The high temperature resistant insulating layer 23 includes at least one of a protective glue 231 and an insulating coating 232. The protective glue 231 is arranged between the adapter 2212 and the first wall 211. The pole ear connection part 2212b and the pole ear 2211 are covered by the protective glue 231, and the terminal connection part 2212a is not covered by the protective glue 231. The insulating coating 232 is located between the end cover and the plastic part 214. The battery cell 20 also includes a high temperature resistant protective film 24, which covers at least part of the shell 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.

[0162] 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 .

[0163] A second aspect of the present application provides a battery 100 , comprising the battery cell 20 provided in the first aspect.

[0164] A third aspect of the present application provides an electrical device, comprising the battery 100 provided in the second aspect, and the battery 100 is used to provide electrical energy to the electrical device.

[0165] The power-consuming device may be any of the aforementioned devices or systems using batteries.

[0166] It should be noted that, in the absence of conflict, the features in the embodiments of this application may be combined with each other.

[0167] 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 embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A battery cell, characterized in that: include: A housing, comprising a first wall and an electrode terminal, wherein the electrode terminal is disposed on the first wall; An electrode assembly is disposed in the housing, the electrode assembly includes an electrode connector, and the electrode connector is electrically connected to the electrode terminal; as well as The 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, characterized in that: The electrode connector includes a tab and a transfer sheet, the transfer sheet 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 disposed between the adapter plate and the first wall. Along the thickness direction of the first wall, the projection of the pole ear connecting portion and the projection of the pole ear are at least partially located within the projection range of the protective glue.

3. The battery cell according to claim 2, characterized in that: In the adapter sheet, the number of the tab connection parts is multiple, 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 comprises a plurality of films, and the plurality of films are arranged in one-to-one correspondence with the plurality of tab connecting parts.

4. The battery cell according to claim 3, characterized in that: The length of the film is greater than or equal to the length of the adapter sheet, 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, characterized in that: The pole lug comprises a plurality of pole lug 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-14 mm.

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

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

8. The battery cell according to claim 2, characterized in that: The thickness of the protective glue is 0.1mm-0.5mm.

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

10. The battery cell according to claim 2, characterized in that: The melting point of the protective glue is 320°C to 500°C.

11. The battery cell according to claim 10, characterized in that: 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 claim 2, characterized in that: The protective adhesive is PI tape or Teflon tape.

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

14. The battery cell according to claim 13, characterized in that: The insulating coating is disposed 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, characterized in that: 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 claim 13, characterized in that: The heat-resistant temperature of the insulating coating is 400°C to 1000°C.

17. The battery cell according to claim 13, characterized in that: The material of the insulating coating includes organic polymer or 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 claim 13, characterized in that: 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 12, characterized in that: 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, characterized in that: The material of the high temperature resistant protective film includes PI glue.

21. The battery cell according to claim 19, characterized in that: The thickness of the high temperature resistant protective film is 0.15 mm to 0.25 mm.

22. A battery, characterized in that: The invention comprises a battery cell as claimed in any one of claims 1 to 21.

23. An electrical device, characterized in that: The battery as claimed in claim 22 is used to provide electrical energy to the electrical device.

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