Battery monomer and assembly method thereof, hot melting device, battery device and electric equipment

Abstract

The invention provides a battery monomer and an assembly method thereof, a hot melting device, a battery device and electric equipment, and belongs to the technical field of batteries. The battery monomer comprises a shell, an electrode assembly and an isolation assembly, a pressure relief channel is arranged at the bottom of the shell in the height direction of the shell. The electrode assembly is arranged in the shell. The isolation assembly comprises a supporting piece, an insulating film and a connecting block, the supporting piece is arranged between the bottom of the shell and the electrode assembly and used for supporting the electrode assembly, and the heat-resistant temperature of the supporting piece is larger than 300 DEG C. The insulating film coats the outer surface of the electrode assembly; the connecting block is connected with the supporting piece, and the connecting block is connected with the insulating film in a hot melting mode. The supporting piece can maintain enough mechanical strength in a thermal runaway test or under the actual thermal runaway condition, so that the smoothness of the pressure relief channel is guaranteed, and the safety performance of the battery monomer is improved.

Description

Technical Field

[0001] The present application relates to the technical field of batteries, and particularly to a battery cell, an assembly method thereof, a hot melting device, a battery device and an electrical equipment. Background Art

[0002] Energy conservation and emission reduction are the keys to the sustainable development of society. Rechargeable batteries have the characteristics of storing energy or releasing energy according to needs, and thus are widely used in various electrical equipment, and are an important part of promoting energy transformation and sustainable development. For the new energy industry, battery technology is an important factor related to its development.

[0003] With the continuous development of battery technology, the safety of batteries has been increasingly emphasized. An explosion-proof valve is usually designed on the battery. When the battery operates abnormally and generates gas inside, the gas can be discharged through the explosion-proof valve to reduce the internal pressure, thereby reducing the probability of larger safety accidents such as explosion. Therefore, how to reliably release the internal pressure of the battery cell is a technical problem to be solved urgently. Summary of the Invention

[0004] The present application aims to solve at least one of the technical problems existing in the background art. For this reason, an object of the present application is to provide a battery cell, an assembly method thereof, a hot melting device, a battery device and an electrical equipment, so as to improve the reliability of releasing the internal pressure of the battery cell, thereby improving the safety performance of the battery cell.

[0005] An embodiment of the first aspect of the present application provides a battery cell, including: a housing, an electrode assembly and an isolation assembly. A pressure relief channel is provided at the bottom of the housing along its height direction. The electrode assembly is disposed inside the housing. The isolation assembly includes a support member, an insulating film and a connection block. The support member is disposed between the bottom of the housing and the electrode assembly and is used to support the electrode assembly. The heat-resistant temperature of the support member is greater than 300 degrees Celsius. The insulating film covers the outer surface of the electrode assembly; the connection block is connected to the support member, and the connection block is thermally melted and connected to the insulating film.

[0006] In the technical solution of the embodiment of the present application, the connection block connected to the support member is thermally melted and connected to the insulating film to reliably connect the support member and the insulating film as a whole. At the same time, the heat-resistant temperature of the support member is set to be greater than 300 degrees Celsius, so that the mechanical strength of the support member will not be affected by the thermal melting temperature when the connection block and the insulating film are thermally melted and connected, and the support member can still maintain sufficient mechanical strength during a thermal runaway test or in the case of an actual thermal runaway, so as to be able to reliably support the electrode assembly, thereby reducing the probability of the electrode assembly collapsing and blocking the pressure relief channel, ensuring the smoothness of the pressure relief channel, improving the reliability of releasing the internal pressure in the battery cell, reducing the probability of the battery cell catching fire or exploding, and thus improving the safety performance of the battery cell.

[0007] In some embodiments, the connecting block is made of the same material as the insulating film. This can improve the reliability of the connection between the two.

[0008] In some embodiments, the battery cell further includes an end cap, which covers the opening of the housing. The end cap includes an end cap body and an insulating member. The insulating member is disposed on the side of the end cap body facing the electrode assembly and is used to connect with the insulating film. This can achieve overall housing insertion, reduce the problem of affecting the reliability of the support member due to improper assembly, and reduce the risk of the electrode assembly being scratched by the housing during housing insertion.

[0009] In some embodiments, the insulating member is made of the same material as the insulating film, and the insulating member is connected to the insulating film by hot melting. By using the same material to prepare the connecting block, the insulating member and the insulating film, it is convenient to achieve hot melting connection between adjacent two and improve the reliability of the connection.

[0010] In some embodiments, the materials of the connecting block, the insulating film and the insulating member are polypropylene. Then, when hot melting the three, the heating temperature used for hot melting will not affect the mechanical strength of the support member, improving the reliability of the support member.

[0011] In some embodiments, the support member includes a plate body. The plate body has a first surface facing away from the electrode assembly and a second surface facing the electrode assembly. Through holes penetrating the first surface and the second surface are provided on the plate body. The connecting block is connected to the first surface, and at least part of the connecting block is used to pass through the through hole and be fixedly connected to the insulating film. Thus, while achieving reliable connection between the connecting block and the plate body, it can also achieve connection between the connecting block and the insulating film on the side of the second surface.

[0012] In some embodiments, the connecting block includes a first body and a second body. The first body is connected to the first surface. One end of the second body is connected to the first body, and the other end of the second body is used to pass through the through hole and be fixedly connected to the insulating film. Wherein, the orthographic projection of the first body on the first surface completely covers the through hole. Thus, not only can the second body pass through the through hole, but also the first body can play a limiting role, and there is a certain connection area between the first body and the first surface.

[0013] In some embodiments, the distance between the edge of the first body and the edge of the through hole is L1, where L1≥1mm. This provides sufficient connection area between the first body and the plate body, improving the reliability of the connection.

[0014] In some embodiments, the gap between the outer surface of the second body and the inner surface of the through hole is L2, where L2≥1mm. This further improves the assemblability between the two.

[0015] In some embodiments, the height by which the connecting block protrudes from the second surface is H, where 0 ≤ H ≤ 0.1 mm. Thereby, the stress effect of the thermal melting point between the connecting block and the insulating film on the electrode assembly is reduced, and the reliability of the electrode assembly is improved.

[0016] In some embodiments, the support further includes a spacer block located on the side of the plate body facing away from the electrode assembly and connected to the first surface. By providing the spacer block to separate the plate body from the bottom of the housing, the reliability of pressure relief through the pressure relief channel at the bottom of the housing is improved.

[0017] In some embodiments, the height by which the spacer block protrudes from the first surface is H1, and the height by which the connecting block protrudes from the first surface is H2, where H1 > H2. Thereby, the reliability of the connecting block is improved.

[0018] In some embodiments, the height H1 by which the spacer block protrudes from the first surface is ≥ 1.5 mm, and the height H2 by which the connecting block protrudes from the first surface is ≤ 0.75 mm. By reasonably setting the height by which the spacer block protrudes from the first surface and the height by which the connecting block protrudes from the first surface, the probability of the pressure relief channel being blocked can be further reduced.

[0019] In some embodiments, the plate body is further provided with a through hole penetrating the first surface and the second surface, and the through hole is disposed opposite to the pressure relief channel. Thereby, both the infiltration requirement of the electrolyte can be satisfied, and the reliability of pressure relief through the pressure relief channel can be improved.

[0020] In some embodiments, the material of the support is polyimide. This enables the support to maintain sufficient mechanical strength under high-temperature conditions, so that the battery cell can pass the thermal runaway test and maintain good safety performance in the event of an actual thermal runaway.

[0021] The embodiments of the second aspect of the present application provide an assembly method for a battery cell as described in the above embodiments. The method includes: providing a plate body having a first surface facing away from the electrode assembly and a second surface facing the electrode assembly. The plate body is provided with a through hole penetrating the first surface and the second surface. Providing a connecting block, inserting at least a part of the connecting block into the through hole along a first direction, and connecting the connecting block to the first surface. Providing a supporting force along the first direction for the connecting block. Providing an insulating film facing the second surface, and thermally fusing the connecting block to the insulating film. Providing an insulating member, and thermally fusing the insulating member to the insulating film. Wherein, the first direction is the direction from the first surface to the second surface. By connecting the plate body, the connecting block, the insulating film, and the insulating member into an integral structure, the problem of affecting the reliability of the support due to improper assembly is improved, and the risk of the electrode assembly being scratched by the housing during housing insertion is reduced.

[0022] An embodiment of the third aspect of the present application provides a hot-melt device for implementing the assembly method described in the above embodiments, including: a support plate and a hot-melt head. The support plate has a protruding portion, and the protruding portion is used to provide a supporting force in the first direction for the connecting block. The hot-melt head is used to cooperate with the support plate to hot-melt connect the connecting block and the insulating film. Thus, the support member and the insulating film are reliably connected into an integral structure.

[0023] In some embodiments, the orthographic projection of the hot-melt head on the second surface completely covers the hot-melt area of the connecting block. The reliability of the hot-melt connection between the connecting block and the insulating film is improved.

[0024] In some embodiments, the distance between the edge of the hot-melt head and the edge of the hot-melt area is L3, where L3≥5mm. Thus, abnormal problems of hot-melt deviation caused by factors such as equipment positioning, equipment accuracy, or incoming material tolerance can be improved to a certain extent.

[0025] An embodiment of the fourth aspect of the present application provides a battery device, which includes the battery cell in the above embodiments.

[0026] An embodiment of the fifth aspect of the present application provides an electrical equipment, which includes the battery device in the above embodiments, and the battery device is used to provide electrical energy.

[0027] The above description is only an overview of the technical solution of the present application. In order to be able to understand the technical means of the present application more clearly, it can be implemented according to the content of the specification. And in order to make the above and other purposes, features and advantages of the present application more obvious and understandable, the specific embodiments of the present application are specifically exemplified below. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In the drawings, unless otherwise specified, the same reference numerals throughout the several views denote the same or similar components or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments disclosed in accordance with the present application and should not be regarded as limiting the scope of the present application.

[0029] Figure 1 It is a schematic structural diagram of a vehicle according to some embodiments of the present application; Figure 2 It is an exploded structural diagram of a battery device according to some embodiments of the present application; Figure 3 It is an exploded structural diagram of a battery cell according to some embodiments of the present application; Figure 4 It is a schematic structural diagram of a battery cell according to some embodiments of the present application; Figure 5 It is one of the partial structural diagrams of an isolation component according to some embodiments of the present application; Figure 6The second partial structural schematic diagram of the isolation component according to some embodiments of the present application; Figure 7 The third partial structural schematic diagram of the isolation component according to some embodiments of the present application; Figure 8 It is Figure 7 The enlarged structural schematic diagram at A; Figure 9 The schematic diagram of the assembly process of the isolation component according to some embodiments of the present application; Figure 10 It is Figure 9 The enlarged structural schematic diagram at B; Figure 11 The flow schematic diagram of the assembly method according to some embodiments of the present application.

[0030] Explanation of reference numerals: 1000, vehicle; 100, battery device; 200, controller; 300, motor; 10, box body; 11, first part; 12, second part; 20, battery cell; 21, end cover; 21a, electrode terminal; 211, end cover body; 212, insulating part; 22, housing; 22a, pressure relief channel; 23, electrode assembly; 23a, tab; 24, isolation component; 241, support member; 241a, plate body; 241b, cushion block; S1, first surface; S2, second surface; K1, through hole; K2, via hole; K3, positioning hole; 242, insulating film; 243, connecting block; 243a, first body; 243b, second body; 2000, support plate; 2100, protruding part; 3000, hot melt head; F1, first direction. Detailed implementation manners

[0031] Hereinafter, embodiments of the technical solutions of the present application will be described in detail with reference to the drawings. The following embodiments are only used to illustrate the technical solutions of the present application more clearly, and thus are only examples and cannot be used to limit the protection scope of the present application.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs; the terms used herein are for the purpose of describing specific embodiments only 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 drawings are intended to cover non-exclusive inclusion.

[0033] In the description of the embodiments of this application, technical terms such as "first" and "second" are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity, specific order, or primary-secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "a plurality" is more than two, unless otherwise specifically defined.

[0034] Referring to "embodiments" herein means that the specific features, structures, or characteristics described in connection with the embodiments can be included in at least one embodiment of this application. The phrase appearing in various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0035] In the description of the embodiments of this application, the term "and / or" is merely a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after.

[0036] In the description of the embodiments of this application, the term "a plurality" 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).

[0037] In the description of the embodiments of this application, the orientation or positional relationship indicated by technical terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the embodiments of this application and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of this application.

[0038] In the description of the embodiments of the present application, unless otherwise clearly defined and limited, technical terms such as "installation", "connection", "fixation", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components. 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 specific situations.

[0039] Currently, from the perspective of the development of the market situation, rechargeable batteries are more and more widely used. Rechargeable batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power stations, but also widely used in various electronic devices, such as electric vehicles, electric motorcycles, electric vehicles and other electric transportation tools, as well as many fields such as aerospace. With the continuous expansion of the application fields of rechargeable batteries, the market demand is also constantly increasing.

[0040] With the continuous development of battery technology, the safety of batteries has received more and more attention. An explosion-proof valve is usually designed on the battery. When the battery operates abnormally and generates gas inside, the gas can be discharged through the explosion-proof valve to reduce the internal pressure, thereby reducing the probability of larger safety accidents such as explosion.

[0041] In some cases, a battery cell may include a housing, an electrode assembly, and a bottom support plate. The bottom support plate is disposed at the bottom of the housing and is used to support the electrode assembly. At the same time, an explosion-proof valve is provided at the bottom of the housing. After the battery cell is assembled, a thermal runaway test needs to be carried out. The main method of the thermal runaway test is to heat the battery cell by a heating device. During the thermal runaway test, the bottom support plate melts, and the electrode assembly collapses under the action of gravity and blocks the explosion-proof valve, making the gas unable to be effectively discharged, resulting in a sharp increase in the internal pressure of the battery cell, and even causing situations such as fire or explosion, and then resulting in the failure of the thermal runaway test, that is, the safety performance of the battery cell is poor.

[0042] Based on the above considerations, the present application provides a battery cell, its assembly method, a hot melting device, a battery device, and an electrical device. The battery cell includes: a housing, an electrode assembly, and an isolation assembly. A pressure relief channel is provided at the bottom of the housing along its height direction. The electrode assembly is disposed in the housing. The isolation assembly includes a support member, an insulating film, and a connecting block. The support member is disposed between the bottom of the housing and the electrode assembly and is used to support the electrode assembly. The heat-resistant temperature of the support member is greater than 300 degrees Celsius. The insulating film covers the outer surface of the electrode assembly; the connecting block is connected to the support member, and the connecting block is thermally fused to the insulating film.

[0043] By thermally fusing the connection block connected to the support member with the insulating film, the support member and the insulating film are reliably connected as a whole. At the same time, the heat-resistant temperature of the support member is set to be greater than 300 degrees Celsius, so that the mechanical strength of the support member will not be affected by the thermal fusion temperature when the connection block and the insulating film are thermally fused, and the support member can still maintain sufficient mechanical strength during the thermal runaway test or in the case of actual thermal runaway, so that the electrode assembly can be reliably supported, thereby reducing the probability of the electrode assembly collapsing and blocking the pressure relief channel, ensuring the smoothness of the pressure relief channel, improving the reliability of the pressure release inside the battery cell, reducing the probability of the battery cell catching fire or exploding, and thus improving the safety performance of the battery cell.

[0044] The battery cell disclosed in the embodiments of the present application can be but is not limited to being used in electrical equipment such as vehicles, ships or aircraft. A power supply system of the electrical equipment can be composed of the battery cell, battery device, etc. disclosed in the present application. In this way, it is beneficial to improve the overall safety performance.

[0045] The embodiments of the present application provide an electrical equipment using a battery device as a power source. The electrical equipment can be but is not limited to mobile phones, tablets, laptop computers, electric toys, electric tools, battery cars, electric vehicles, ships, spacecraft, etc. Among them, the electric toy can include fixed or mobile electric toys, such as game consoles, electric vehicle toys, electric ship toys and electric aircraft toys, etc. The spacecraft can include airplanes, rockets, space shuttles and spaceships, etc.

[0046] The electrical equipment can also be an energy storage device. The energy storage device can be but is not limited to an energy storage container, an energy storage cabinet, an energy storage power station, an energy storage battery pack or a portable energy storage system, etc.

[0047] For the convenience of description in the following embodiments, a vehicle 1000, which is an electrical equipment according to an embodiment of the present application, is taken as an example for description.

[0048] Please refer to Figure 1 , Figure 1 which is a schematic structural diagram of a vehicle provided by 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 device 100 is arranged inside the vehicle 1000. The battery device 100 can be arranged at the bottom, head or tail of the vehicle 1000. The battery device 100 can be used for power supply of the vehicle 1000. For example, the battery device 100 can be used as the operating power source of the vehicle 1000. The vehicle 1000 can also include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300. For example, it is used for the working power requirements during the start, navigation and driving of the vehicle 1000.

[0049] In some embodiments of the present application, the battery device 100 can not only serve as the operating power source of the vehicle 1000, but also as the driving power source of the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0050] Please refer to Figure 2 , Figure 2 which is an exploded structural schematic diagram of the battery device provided in some embodiments of the present application. The battery device 100 includes a box body 10 and battery cells 20, and the battery cells 20 are accommodated in the box body 10. Among them, the box body 10 is used to provide an accommodation space for the battery cells 20, and the box body 10 can adopt various structures. In some embodiments, the box body 10 may include a first part 11 and a second part 12, the first part 11 and the second part 12 cover each other, and the first part 11 and the second part 12 jointly define an accommodation space for accommodating the battery cells 20. The second part 12 may be a hollow structure with one end open, and the first part 11 may be a plate-like structure. 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 an accommodation space; the first part 11 and the second part 12 may also both 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 of various shapes, such as a cylinder, a cuboid, etc.

[0051] In the battery device 100, there may be multiple battery cells 20, and the multiple battery cells 20 can be connected in series, in parallel, or in a hybrid connection. A hybrid connection means that there are both series and parallel connections among the multiple battery cells 20. The multiple battery cells 20 can be directly connected in series, in parallel, or in a hybrid connection together, and then the whole formed by the multiple battery cells 20 is accommodated in the box body 10; of course, the battery device 100 can also be that multiple battery cells 20 are first connected in series, in parallel, or in a hybrid connection to form a battery module form, and then multiple battery modules are connected in series, in parallel, or in a hybrid connection to form a whole and are accommodated in the box body 10. The battery device 100 may further include other structures. For example, the battery device 100 may further include a busbar component for realizing the electrical connection among the multiple battery cells 20.

[0052] Among them, each battery cell 20 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but not limited thereto. The battery cell 20 can be in the shape of a cylinder, a flat body, a cuboid, or other shapes, etc.

[0053] Please refer to Figure 3 , Figure 3 which is an exploded structural schematic diagram of the battery cell provided in some embodiments of the present application. The battery cell 20 refers to the smallest unit that makes up the battery device. As Figure 3, the battery cell 20 includes an end cap 21, a housing 22, an electrode assembly 23, and other functional components.

[0054] The end cap 21 refers to a component that covers the opening of the housing 22 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 21 can be adapted to the shape of the housing 22 to fit the housing 22. Optionally, the end cap 21 can be made of a material with a certain hardness and strength (such as aluminum alloy). In this way, the end cap 21 is not easily deformed when subjected to extrusion and collision, enabling the battery cell 20 to have higher structural strength and improved safety performance. Functional components such as electrode terminals 21a can be provided on the end cap 21. The electrode terminals 21a can be used to electrically connect to the electrode assembly 23 for outputting or inputting the electrical energy of the battery cell 20. In some embodiments, a pressure relief mechanism for releasing the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold can also be provided on the end cap 21. The material of the end cap 21 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc. In some embodiments, an insulating member can be provided on the inner side of the end cap 21. The insulating member can be used to isolate the electrical connection components in the housing 22 from the end cap 21 to reduce the risk of short circuit. Exemplarily, the insulating member can be plastic, rubber, etc.

[0055] The housing 22 is a component used to cooperate with the end cap 21 to form the internal environment of the battery cell 20, wherein the formed internal environment can be used to accommodate the electrode assembly 23, the electrolyte, and other components. The housing 22 and the end cap 21 can be independent components. An opening can be provided on the housing 22, and the end cap 21 is covered on the opening to form the internal environment of the battery cell 20. Without limitation, the end cap 21 and the housing 22 can also be integrated. Specifically, the end cap 21 and the housing 22 can first form a common connection surface before other components are put into the housing, and when it is necessary to encapsulate the inside of the housing 22, the end cap 21 is then covered on the housing 22. The housing 22 can be of various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing 22 can be determined according to the specific shape and size of the electrode assembly 23. The material of the housing 22 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0056] The electrode assembly 23 is a component in the battery cell 20 where an electrochemical reaction occurs. The housing 22 can contain one or more electrode assemblies 23. The electrode assembly 23 is mainly formed by winding or laminating 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 portions of the positive electrode sheet and the negative electrode sheet having active materials constitute the main body of the electrode assembly, and the portions of the positive electrode sheet and the negative electrode sheet without active materials respectively constitute the electrode tabs 23a. The positive electrode tab and the negative electrode tab can be located together at one end of the main body or respectively at both ends of the main body. During the charge and discharge process of the battery, the positive active material and the negative active material react with the electrolyte, and the electrode tabs 23a are connected to the electrode terminals to form a current loop.

[0057] Combined Figure 4 as shown Figure 4 is a schematic structural diagram of a battery cell according to some embodiments of the present application. Embodiments of the present application provide a battery cell 20, including: a housing 22, an electrode assembly 23, and an isolation assembly 24. A pressure relief channel 22a is provided at the bottom of the housing 22 along its height direction. The electrode assembly 23 is disposed within the housing 22. The isolation assembly 24 includes a support member 241, an insulating film 242, and a connection block 243. The support member 241 is disposed between the bottom of the housing 22 and the electrode assembly 23 and is used to support the electrode assembly 23. The heat-resistant temperature of the support member 241 is greater than 300 degrees Celsius. The insulating film 242 covers the outer surface of the electrode assembly 23; the connection block 243 is connected to the support member 241, and the connection block 243 is thermally fused to the insulating film 242.

[0058] The battery cell 20 refers to the smallest unit that makes up the battery device 100.

[0059] In the battery cell 20, the housing 22 is a component used to cooperate with the end cap 21 to form the internal environment of the battery cell 20. Among them, the formed internal environment can be used to accommodate the electrode assembly 23, the electrolyte, and other components. The pressure relief channel 22a is a structure used to discharge the gas generated during the abnormal operation of the battery cell 20. The gas is discharged through the pressure relief channel 22a to reduce the pressure inside the housing 22, thereby reducing the probability of the battery cell 20 catching fire or exploding. In some embodiments, an explosion-proof valve is provided on the pressure relief channel 22a. When the pressure inside the housing 22 reaches a preset value, the explosion-proof valve opens to achieve pressure relief.

[0060] The electrode assembly 23 is a component in the battery cell 20 where an electrochemical reaction occurs.

[0061] The isolation assembly 24 is a component used to isolate the electrode assembly 23 from the housing 22 to a certain extent to reduce the risk of short circuit.

[0062] Among them, the support member 241 is a component for supporting the electrode assembly 23, and can isolate the electrode assembly 23 from the pressure relief channel 22a, so that the pressure relief channel 22a can remain unobstructed, thereby improving the reliability of pressure relief.

[0063] The heat-resistant temperature refers to the highest temperature before the mechanical strength of the material is significantly reduced. By selecting a material with a higher heat-resistant temperature to prepare the support member 241, the mechanical strength of the support member 241 can be maintained under high-temperature conditions, so that the support member 241 can reliably support the electrode assembly 23, thereby reducing the probability of the electrode assembly 23 collapsing and blocking the pressure relief channel 22a. In some cases, the temperature at which the battery cell 20 operates abnormally and undergoes thermal runaway can reach 300 degrees Celsius. By selecting a material with a heat-resistant temperature greater than 300 degrees Celsius to prepare the support member 241, the support member 241 can still maintain sufficient mechanical strength to support the electrode assembly 23 at this thermal runaway temperature.

[0064] The insulating film 242 is a component for covering the electrode assembly 23 to isolate the electrode assembly 23 from the inner wall surface of the housing 22. Under the isolation of the insulating film 242, the risk of the electrode assembly 23 short-circuiting through the housing 22 can be reduced. And when the electrode assembly 23 is inserted into the housing, the insulating film 242 can also protect the electrode assembly 23 to reduce the risk of the electrode assembly 23 being scratched by the housing 22. In some embodiments, the insulating film 242 can be a Mylar film.

[0065] The connecting block 243 is a component for connecting the support member 241 and the insulating film 242 into a whole, so that the whole can be inserted into the housing. By inserting the whole into the housing, the problem that the support member 241 is not properly assembled in the housing 22 can be improved, and the problem that the reliability of the support member 241 is affected due to improper assembly can be reduced. In some embodiments, the connection method between the connecting block 243 and the support member 241 can be bonding.

[0066] Thermal fusion connection refers to a connection method between non-metals. After heating up to the melting point of the material, the connection between each other can be achieved. In some cases, the temperature of the thermal fusion connection is usually controlled below 300 degrees Celsius, that is, the connecting block 243 and the insulating film 242 are thermally fused below 300 degrees Celsius, so as to connect the support member 241 and the insulating film 242 into a whole component. And this thermal fusion temperature is lower than the heat-resistant temperature of the support member 241, so that during the thermal fusion connection process of the connecting block 243 and the insulating film 242, neither the support strength of the support member 241 will be affected, nor will the support member 241 change its initial shape, thus being able to meet the reliable support for the connection assembly 23.

[0067] In some cases, the abnormal operation of the battery cell 20 and the temperature at which thermal runaway occurs can reach 300 degrees Celsius. Therefore, in the thermal runaway test, the heating device is used to heat the battery cell 20 to simulate the temperature of the battery cell 20 during thermal runaway, and relevant parameters are monitored to determine whether the thermal runaway test of the battery cell 20 passes, and thus to a certain extent, determine whether the safety performance of the battery cell 20 is qualified.

[0068] The test method of the thermal runaway test will be described below.

[0069] The test environmental temperature is 22°C ± 5°C, the relative humidity is 15% - 90%, and the atmospheric pressure is 86 kPa - 106 kPa.

[0070] A planar or rod-shaped heating device is used to directly contact the battery cell 20, and temperature sensors are installed at the monitoring points corresponding to the battery cell 20. After the battery cell 20 to be tested is fully charged, the heating device is started, and the battery cell 20 is continuously heated at its maximum power. When thermal runaway occurs or the temperature at the monitoring point reaches 300 degrees Celsius, the heating device is turned off.

[0071] Among them, the determination conditions for thermal runaway are as follows: a. The battery cell generates a voltage drop, and the drop value exceeds 25% of the initial voltage; b. The temperature at the monitoring point reaches the maximum operating temperature specified by the battery manufacturer; c. The temperature rise rate d of the monitoring point T / d t ≥1°C / s and lasts for more than 3 s.

[0072] When condition a and condition c occur, or when condition b and condition c occur, it can be determined that thermal runaway has occurred.

[0073] During the heating process or within 1 h after the heating ends, if the battery cell 20 catches fire or explodes, the test is terminated and the test fails.

[0074] The main reason for the failure of the thermal runaway test is that the pressure inside the battery cell 20 cannot be released in a timely and effective manner, resulting in phenomena such as fire or explosion. One of the reasons for the inability to release the pressure in a timely and effective manner is that the support member 241 melts during the heating process, resulting in a reduction in the mechanical strength of the support member 241, so that the electrode assembly 23 cannot be effectively supported, and the electrode assembly 23 collapses under the action of gravity and blocks the pressure relief channel 22a.

[0075] Accordingly, by setting the heat-resistant temperature of the support member 241 to be greater than 300 degrees Celsius, the support member 241 can maintain sufficient mechanical strength during a thermal runaway test or in the event of an actual thermal runaway, thereby being able to reliably support the electrode assembly 23, and further reducing the probability that the electrode assembly 23 collapses and blocks the pressure relief channel 22a, enhancing the safety performance of the battery cell 20.

[0076] In some embodiments, the material of the support member 241 can be polyimide (abbreviated as PI), and the heat-resistant temperature of PI can reach above 400 degrees Celsius. Thus, the support member 241 made of PI can maintain sufficient mechanical strength at 300 degrees Celsius to support the electrode assembly 23.

[0077] In some other embodiments, the materials of the connecting block 243 and the insulating film 242 are polypropylene (abbreviated as PP). The melting point of PP is 164 - 176 °C, which is lower than the heat-resistant temperature of the support member 241. During hot melt connection, the heating temperature can be controlled within the melting point range of PP. Accordingly, not only can the hot melt connection between the connecting block 243 and the insulating film 242 be achieved, but also the mechanical strength of the support member 241 will not be affected.

[0078] By hot melt connecting the connecting block 243 connected to the support member 241 and the insulating film 242, the support member 241 and the insulating film 242 can be reliably connected as a whole. At the same time, by setting the heat-resistant temperature of the support member 241 to be greater than 300 degrees Celsius, the mechanical strength of the support member 241 will not be affected by the hot melt temperature during the hot melt connection of the connecting block 243 and the insulating film 242, and the support member 241 can still maintain sufficient mechanical strength during a thermal runaway test or in the event of an actual thermal runaway. Thereby, it can reliably support the electrode assembly 23, further reducing the probability that the electrode assembly 23 collapses and blocks the pressure relief channel 22a, ensuring the smoothness of the pressure relief channel 22a, enhancing the reliability of pressure release within the battery cell 20, and reducing the probability of the battery cell 20 catching fire or exploding. Thus, the safety performance of the battery cell 20 is enhanced.

[0079] According to some embodiments of the present application, the materials of the connecting block 243 and the insulating film 242 are the same.

[0080] Since the materials of the connecting block 243 and the insulating film 242 are the same, their melting points are the same. Within the melting point range, both can melt simultaneously, facilitating the hot melt connection between them. At the same time, the same material can further enhance the reliability of the hot melt connection between them.

[0081] In some embodiments, the connection block 243 and the insulating film 242 are made of polypropylene (PP for short). The melting point of PP is 164 - 176°C, and the melting point of PP is lower than the heat resistance temperature of the support member 241. During hot melt connection, the heating temperature can be controlled within the melting point range of PP. Thus, not only can the hot melt connection between the connection block 243 and the insulating film 242 be achieved, but also the mechanical strength of the support member 241 will not be affected.

[0082] By using the same material to prepare the connection block 243 and the insulating film 242, it is convenient to achieve the hot melt connection between the two and can improve the reliability of the connection between the two.

[0083] Combined Figure 4 As shown, according to some embodiments of the present application, the battery cell 20 further includes an end cap 21, and the end cap 21 covers the opening of the housing 22. The end cap 21 includes an end cap body 211 and an insulating member 212. The insulating member 212 is disposed on the side of the end cap body 211 facing the electrode assembly 23, and the insulating member 212 is used to connect with the insulating film 242.

[0084] The end cap 21 refers to a component that covers the opening of the housing 22 to isolate the internal environment of the battery cell 20 from the external environment.

[0085] The end cap body 211 is a component for sealing the opening of the housing 22, and the insulating member 212 is a component for isolating the electrode assembly 23 and the pole post on the end cap 21 from the end cap body 211 to prevent short - circuit of the positive and negative electrodes through the end cap body 211. At the same time, the insulating member 212 can further cooperate with the end cap body 211 to achieve sealing. In some embodiments, the insulating member 212 can be a lower plastic.

[0086] Connecting the insulating member 212 with the insulating film 242 to connect the insulating member 212, the insulating film 242, the connection block 243 and the support member 241 into a whole, so that the whole can be inserted into the housing. By inserting the whole into the housing, the problem that the support member 241 is not properly assembled in the housing can be improved, and the problem of affecting the reliability of the support member 241 due to improper assembly can be reduced. At the same time, inserting the whole into the housing can also reduce the risk of the electrode assembly 23 being scratched when inserted into the housing.

[0087] In some embodiments, the connection method between the insulating member 212 and the insulating film 242 can be hot melt connection.

[0088] Through the connection between the insulating member 212 and the insulating film 242, the insulating member 212, the insulating film 242, the connecting block 243 and the supporting member 241 can be reliably connected as a whole, thereby enabling the whole to be inserted into the housing. This reduces the problem of affecting the reliability of the supporting member 241 due to improper assembly and also reduces the risk of the electrode assembly 23 being scratched by the housing 22 when inserted into the housing.

[0089] According to some embodiments of the present application, the insulating member 212 and the insulating film 242 are made of the same material, and the insulating member 212 and the insulating film 242 are connected by hot melting.

[0090] Since the insulating member 212 and the insulating film 242 are made of the same material, their melting points are the same. Within the melting point range, both can be melted simultaneously to facilitate the hot melting connection between them. At the same time, the same material can further improve the reliability of the hot melting connection between them.

[0091] Since the connecting block 243 and the insulating film 242 are also made of the same material, that is, the connecting block 243, the insulating film 242 and the insulating member 212 are all made of the same material.

[0092] In some embodiments, the connecting block 243, the insulating film 242 and the insulating member 212 are made of polypropylene (PP for short). The melting point of PP is 164 - 176 °C. Since the melting point of PP is lower than the heat resistance temperature of the supporting member 241, during hot melting connection, the heating temperature can be controlled within the melting point range of PP. Thus, not only can the hot melting connection between the connecting block 243 and the insulating film 242 and the hot melting connection between the insulating film 242 and the insulating member 212 be achieved, but also the mechanical strength of the supporting member 241 will not be affected.

[0093] By using the same material to prepare the connecting block 243, the insulating member 212 and the insulating film 242, it is convenient to achieve the hot melting connection between adjacent two and can improve the reliability of the connection.

[0094] According to some embodiments of the present application, the connecting block 243, the insulating film 242 and the insulating member 212 are made of polypropylene.

[0095] The melting point of polypropylene is 164 - 176 °C, that is, the melting point is lower than the heat resistance temperature of the supporting member 241. During hot melting connection, the heating temperature can be controlled within the melting point range of polypropylene. Thus, not only can the hot melting connection between the connecting block 243 and the insulating film 242 and the hot melting connection between the insulating film 242 and the insulating member 212 be achieved, but also the mechanical strength of the supporting member 241 will not be affected.

[0096] By setting the materials of the connecting block 243, the insulating film 242, and the insulating member 212 to polypropylene, when heat-meltingly connecting the three, the heating temperature used for heat-melting will not affect the mechanical strength of the support member 241, improving the reliability of the support member 241.

[0097] Combined Figures 4 to 8 as shown Figure 4 is a schematic structural diagram of a battery cell according to some embodiments of the present application; Figure 5 is one of the partial structural diagrams of an isolation component according to some embodiments of the present application; Figure 6 is another partial structural diagram of an isolation component according to some embodiments of the present application; Figure 7 is a third partial structural diagram of an isolation component according to some embodiments of the present application; Figure 8 is Figure 7 an enlarged structural diagram at A.

[0098] According to some embodiments of the present application, the support member 241 includes a plate body 241a. The plate body 241a has a first surface S1 facing away from the electrode assembly 23 and a second surface S2 facing the electrode assembly 23. A through hole K1 penetrating the first surface S1 and the second surface S2 is provided on the plate body 241a. The connecting block 243 is connected to the first surface S1, and at least a part of the connecting block 243 is used to pass through the through hole K1 and be fixedly connected to the insulating film 242.

[0099] The plate body 241a is a component for supporting the electrode assembly 23. The through hole K1 on the plate body 241a is a structure for the connecting block 243 to pass through, so that the connecting block 243 can be connected to the insulating film 242 on the side of the second surface S2. During assembly, the connecting block 243 can be passed through the through hole K1 along the direction from the first surface S1 to the second surface S2, and the connecting block 243 can be bonded to the first surface S1 to pre-connect the connecting block 243 and the plate body 241a as a whole. Then, the insulating film 242 on the side of the second surface S2 and the connecting block 243 are connected by heat-melting, so as to connect the plate body 241a, the connecting block 243, and the insulating film 242 as a whole, facilitating the overall housing insertion. Among them, the thickness of the plate body 241a can be set to be greater than or equal to 0.3 mm, so that the plate body 241a has sufficient strength.

[0100] In some embodiments, a plurality of through holes K1 can be uniformly provided on the plate body 241a, so that a plurality of connecting blocks 243 can be connected to the insulating film 242, improving the reliability of the connection. In Figure 5 and Figure 6 it is schematically shown that there are eight through holes K1 and eight connecting blocks 243 provided in one-to-one correspondence.

[0101] In some other embodiments, the orthographic projection of the connection block 243 on the second surface S2 is rectangular, and correspondingly, the cross-sectional shape of the through hole K1 is rectangular.

[0102] By providing the through hole K1 on the plate body 241a for the connection block 243 to pass through, while achieving a reliable connection between the connection block 243 and the plate body 241a, it is also possible to connect the connection block 243 with the insulating film 242 on one side of the second surface S2.

[0103] Combined Figure 8 As shown, according to some embodiments of the present application, the connection block 243 includes a first body 243a and a second body 243b. The first body 243a is connected to the first surface S1. One end of the second body 243b is connected to the first body 243a, and the other end of the second body 243b is used to pass through the through hole K1 and is fixedly connected to the insulating film 242. Among them, the orthographic projection of the first body 243a on the first surface S1 completely covers the through hole K1.

[0104] The orthographic projection of the first body 243a on the first surface S1 completely covers the through hole K1. It can be understood that the cross-sectional area of the first body 243a is larger than the cross-sectional area of the through hole K1, so the first body 243a cannot pass through the through hole K1, such that when the second body 243b passes through the through hole, the first body 243a can play a limiting role. At the same time, since the cross-sectional area of the first body 243a is larger than the cross-sectional area of the through hole K1, there is a certain contact area between the first body 243a and the first surface S1, thereby being able to improve the reliability of the connection between the first body 243a and the first surface S1.

[0105] And the second body 243b can pass through the through hole K1, so the cross-sectional area of the through hole K1 is larger than the cross-sectional area of the second body 243b. Thus, the cross-sectional area of the first body 243a is larger than the cross-sectional area of the second body 243b. The connection block 243 has a two-part structure with different cross-sectional areas.

[0106] In some embodiments, the first body 243a and the second body 243b can be an integral structure.

[0107] By setting the connection block 243 as a two-part structure with different cross-sectional areas, it not only enables the second body 243b to pass through the through hole K1, but also enables the first body 243a to play a limiting role, and also enables there to be a certain connection area between the first body 243a and the first surface S1.

[0108] Combined Figure 8 As shown, according to some embodiments of the present application, the distance between the edge of the first body 243a and the edge of the through hole K1 is L1, where L1≥1mm.

[0109] On the basis that the first body 243a can completely cover the through hole K1, the distance between the edge of the first body 243a and the edge of the through hole K1 also satisfies L1≥1mm, so as to provide sufficient connection area between the first body 243a and the plate body 241a, thereby improving the reliability of the connection. Among them, the specific value of L1 can be 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm or 1.5mm, etc., and the value of L1 can be reasonably set according to the assembly space.

[0110] In some embodiments, the first body 243a and the plate body 241a can be bonded by a high-temperature resistant double-sided adhesive.

[0111] By reasonably setting the distance L1 between the edge of the first body 243a and the edge of the through hole K1, sufficient connection area is provided between the first body 243a and the plate body 241a, and the reliability of the connection is improved.

[0112] Combined Figure 8 As shown, according to some embodiments of the present application, the gap between the outer surface of the second body 243b and the inner surface of the through hole K1 is L2, where L2≥1mm.

[0113] On the basis that the cross-sectional area of the second body 243b is smaller than the cross-sectional area of the through hole K1, the gap between the outer surface of the second body 243b and the inner surface of the through hole K1 also satisfies L2≥1mm, so as to facilitate the assembly between the second body 243b and the through hole K1, and further improve the assemblability between the two. Among them, the specific value of L2 can be 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm or 1.5mm, etc.

[0114] By reasonably setting the gap L2 between the outer surface of the second body 243b and the inner surface of the through hole K1, the assemblability between the two is further improved.

[0115] Combined Figure 8 As shown, according to some embodiments of the present application, the height of the connecting block 243 protruding from the second surface S2 is H, where 0≤H≤0.1mm.

[0116] After assembling the connecting block 243 with the plate body 241a, the height of the connecting block 243 protruding from the plate body 241a does not exceed 0.1mm. On the basis of facilitating the hot melt connection between the connecting block 243 and the insulating film 242, the hot melt point after hot melting is flat without obvious protrusions, reducing the stress effect of the hot melt point on the electrode assembly 23 and improving the reliability of the electrode assembly 23.

[0117] Among them, the specific value of H can be 0mm, 0.02mm, 0.04mm, 0.06mm, 0.08mm or 0.1mm.

[0118] By reasonably setting the height of the connecting block 243 protruding from the second surface S2, the stress effect of the thermal melting point between the connecting block 243 and the insulating film 242 on the electrode assembly 23 is reduced, and the reliability of the electrode assembly 23 is improved.

[0119] Combined Figures 4 to 7 As shown, according to some embodiments of the present application, the support member 241 further includes a spacer block 241b, and the spacer block 241b is located on the side of the plate body 241a away from the electrode assembly 23 and is connected to the first surface S1.

[0120] The spacer block 241b is a component for supporting the plate body 241a to separate the plate body 241a from the bottom of the housing 22. Under the action of the spacer block 241b, a certain gap is formed between the plate body 241a and the bottom of the housing 22, so that the plate body 241a does not contact the bottom of the housing 22, thereby reducing the probability of clogging of the pressure relief channel 22a at the bottom of the housing 22 by the plate body 241a, and further enabling the pressure relief channel 22a to remain unblocked, improving the reliability of pressure relief.

[0121] In some embodiments, a plurality of spacer blocks 241b can be uniformly arranged to improve the stability of supporting the plate body 241a and the electrode assembly 23. Figure 5 It is shown that 20 spacer blocks 241b are uniformly arranged.

[0122] By arranging the spacer block 241b to separate the plate body 241a from the bottom of the housing 22, the reliability of pressure relief of the pressure relief channel 22a at the bottom of the housing 22 is improved.

[0123] Combined Figure 7 As shown, according to some embodiments of the present application, the height of the spacer block 241b protruding from the first surface S1 is H1, and the height of the connecting block 243 protruding from the first surface S1 is H2, where H1 > H2.

[0124] If the height of the spacer block 241b protruding from the first surface S1 is greater than the height of the connecting block 243 protruding from the first surface S1, the plate body 241a is supported by the spacer block 241b, and the connecting block 243 does not contact the bottom of the housing 22, reducing the probability of the connecting block 243 colliding and falling off from the bottom of the housing 22, and improving the reliability of the connecting block 243.

[0125] By setting the height H1 of the spacer block 241b protruding from the first surface S1 to be greater than the height H2 of the connecting block 243 protruding from the first surface S1, the reliability of the connecting block 243 is improved.

[0126] According to some embodiments of the present application, the height H1 of the spacer block 241b protruding from the first surface S1 ≥ 1.5 mm, and the height H2 of the connecting block 243 protruding from the first surface S1 ≤ 0.75 mm.

[0127] The height H1 of the spacer 241b protruding from the first surface S1 can be appropriately increased to sufficiently separate the plate body 241a from the bottom of the housing 22. The height of the connecting block 243 protruding from the first surface S1 can be appropriately reduced to reduce the probability that the connecting block 243 blocks the pressure relief channel 22a at the bottom of the housing 22.

[0128] In some embodiments, the specific value of H1 can be 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm or 2.0 mm. The specific value of H2 can be 0.75 mm, 0.65 mm, 0.55 mm, 0.45 mm or 0.35 mm.

[0129] By reasonably setting the height H1 of the spacer 241b protruding from the first surface S1 and the height H2 of the connecting block 243 protruding from the first surface S1, the probability of the pressure relief channel 22a being blocked can be further reduced.

[0130] Combined Figure 5 and Figure 6 As shown, according to some embodiments of the present application, the plate body 241a is further provided with a through hole K2 penetrating the first surface S1 and the second surface S2, and the through hole K2 is disposed opposite to the pressure relief channel 22a.

[0131] The through hole K2 is a structure for cooperating with the siphon hole on the insulating film 242 to allow the electrolyte to pass through and infiltrate the electrode assembly 23, and to assist in discharging the gas generated by thermal runaway. Among them, the through hole K2 is also disposed opposite to the pressure relief channel 22a to facilitate discharging the gas through the pressure relief channel 22a in time, thereby improving the reliability of pressure relief.

[0132] In some embodiments, multiple through holes K2 can be provided. Figure 5 and Figure 6 Illustrates that there are 8 through holes K2 provided.

[0133] In some other embodiments, the plate body 241a is further provided with a positioning hole K3 penetrating the first surface S1 and the second surface S2, and the positioning hole K3 is used to position the plate body 241a during the assembly process, thereby improving the assembly accuracy.

[0134] By providing a through hole on the plate body 241a opposite to the pressure relief channel 22a, both the infiltration requirement of the electrolyte can be met and the reliability of the pressure relief of the pressure relief channel 22a can be improved.

[0135] According to some embodiments of the present application, the material of the support member 241 is polyimide.

[0136] The material of the support member 241 is polyimide (abbreviated as PI), that is, the materials of the plate body 241a and the spacer 241b are both PI. The heat-resistant temperature of PI can reach above 400 degrees Celsius. Therefore, the support member 241 made of PI can maintain sufficient mechanical strength at 300 degrees Celsius to support the electrode assembly 23, enabling the battery cell 20 to pass the thermal runaway test and maintain good safety performance in the event of an actual thermal runaway.

[0137] By setting the material of the support member 241 as polyimide, the support member 241 can maintain sufficient mechanical strength under high-temperature conditions, enabling the battery cell 20 to pass the thermal runaway test and maintain good safety performance in the event of an actual thermal runaway.

[0138] Combined Figures 4 to 11 as shown Figure 9 is a schematic diagram of the assembly process of the isolation component according to some embodiments of the present application; Figure 10 is Figure 9 an enlarged structural schematic diagram at B; Figure 11 is a schematic flow diagram of the assembly method according to some embodiments of the present application.

[0139] Embodiments of the second aspect of the present application provide an assembly method for a battery cell as described in any of the above embodiments, including step 1110, step 1120, step 1130, step 1140, and step 1150.

[0140] Step 1110: Provide a plate body 241a, which has a first surface S1 facing away from the electrode assembly 23 and a second surface S2 facing the electrode assembly 23. A through hole K1 penetrating the first surface S1 and the second surface S2 is provided on the plate body 241a.

[0141] Step 1120: Provide a connection block 243, extend at least a part of the connection block 243 into the through hole K1 along the first direction F1, and connect the connection block 243 to the first surface S1.

[0142] Step 1130: Provide a supporting force for the connection block 243 along the first direction F1.

[0143] Step 1140: Provide an insulating film 242, the insulating film 242 faces the second surface S2, and thermally fuse the connection block 243 to the insulating film 242.

[0144] Step 1150: Provide an insulating member 212, and thermally fuse the insulating member 212 to the insulating film 242.

[0145] Wherein, the first direction F1 is the direction from the first surface S1 to the second surface S2.

[0146] In step 1110, the plate body 241a can be fixed and positioned through the positioning hole K3 on the plate body 241a to improve the accuracy of the position of the plate body 241a, thereby improving the accuracy of subsequent assembly.

[0147] In step 1120, the second body 243b of the connecting block 243 is inserted into the through hole K1, and the first body 243a of the connecting block 243 is bonded to the first surface S1 to connect the connecting block 243 and the plate body 241a into an integral structure.

[0148] In step 1130, the connecting block 243 can be supported by the support plate 2000 so that the connecting block 243 does not hang in the air during the hot melting process, thereby enabling the connecting block 243 and the insulating film 242 to be fully hot melted, improving the reliability of the hot melt connection between the connecting block 243 and the insulating film 242.

[0149] In step 1140, through the hot melt connection between the connecting block 243 and the insulating film 242, the plate body 241a, the connecting block 243, and the insulating film 242 are connected into an integral structure, facilitating subsequent overall housing insertion. After step 1140, the insulating film 242 can be wrapped around the electrode assembly 23.

[0150] In step 1150, the insulating film 242 is hot melt connected to the insulating member 212 of the end cap 21, thereby obtaining an integral structure including the plate body 241a, the connecting block 243, the insulating film 242, and the insulating member 212, facilitating overall housing insertion.

[0151] By connecting the plate body 241a, the connecting block 243, the insulating film 242, and the insulating member 212 into an integral structure, the problem of affecting the reliability of the support member 241 due to improper assembly is improved, and the risk of the electrode assembly 23 being scratched by the housing 22 during housing insertion is reduced.

[0152] Combined Figure 9 and Figure 10 As shown, the embodiment of the third aspect of the present application provides a hot melt device for implementing the assembly method as described in any one of the above embodiments, including a support plate 2000 and a hot melt head 3000. The support plate 2000 has a protruding portion 2100, and the protruding portion 2100 is used to provide a supporting force for the connecting block 243 along the first direction F1. The hot melt head 3000 is used to cooperate with the support plate 2000 to hot melt connect the connecting block 243 and the insulating film 242.

[0153] Since the height H1 by which the spacer block 241b protrudes from the first surface S1 is greater than the height H2 by which the connecting block 243 protrudes from the first surface S1, by providing the protruding portion 2100 on the support plate 2000 such that the protruding portion 2100 can contact the connecting block 243 while the support plate 2000 does not contact the spacer block 241b, the purpose that the connecting block 243 will not be suspended during the hot melting process is achieved.

[0154] The hot melting head 3000 faces the second surface S2 and presses the insulating film 242 against the connecting block 243. The high temperature generated by the hot melting head 3000 melts the insulating film 242 and the connecting block 243. Within this temperature range, the support member 241 can always maintain sufficient mechanical strength, and the connection between the insulating film 242 and the connecting block 243 can be achieved after cooling.

[0155] The hot melting connection between the connecting block 243 and the insulating film 242 is realized through the hot melting device, thereby reliably connecting the support member 241 and the insulating film 242 into an integral structure.

[0156] Combined Figure 10 As shown, according to some embodiments of the present application, the orthographic projection of the hot melting head 3000 on the second surface S2 completely covers the hot melting area of the connecting block 243.

[0157] The hot melting head 3000 completely covers the hot melting area of the connecting block 243, and the projected area of the hot melting head 3000 is larger than the hot melting area. Then, the connecting block 243 in the hot melting area can be fully heated and melted, further improving the reliability of the hot melting connection between the connecting block 243 and the insulating film 242.

[0158] By completely covering the hot melting area of the connecting block 243 with the hot melting head 3000, the reliability of the hot melting connection between the connecting block 243 and the insulating film 242 is improved.

[0159] Combined Figure 10 As shown, according to some embodiments of the present application, the distance between the edge of the hot melting head 3000 and the edge of the hot melting area is L3, where L3≥5mm.

[0160] On the basis that the projected area of the hot melting head 3000 is larger than the hot melting area, the distance L3 between the edge of the hot melting head 3000 and the edge of the hot melting area can be further appropriately increased, reducing the difficulty and precision of positioning the hot melting head 3000. Thus, the abnormal problem of hot melting deviation caused by factors such as equipment positioning, equipment precision, or incoming material tolerance can be improved to a certain extent.

[0161] In some embodiments, the value of L3 can be 5mm, 5.5mm, 6mm, 6.5mm, or 7mm.

[0162] By reasonably setting the distance between the edge of the hot melt head 3000 and the edge of the hot melt area, abnormal problems such as hot melt deviation caused by factors such as equipment positioning, equipment accuracy, or incoming material tolerance can be improved to a certain extent.

[0163] An embodiment of the fourth aspect of the present application provides a battery device 100 including the battery cell 20 described in any one of the above embodiments.

[0164] The battery device 100 in this embodiment can have all the beneficial effects of the above battery cell 20, which will not be elaborated here.

[0165] An embodiment of the fifth aspect of the present application provides an electrical device including the battery device 100 described in any one of the above embodiments, and the battery device 100 is used to provide electrical energy.

[0166] The electrical device in this embodiment can have all the beneficial effects of the above battery device 100, which will not be elaborated here.

[0167] Next, in conjunction with Figures 4 to 11 A further detailed description of the embodiments of the present application will be given.

[0168] The battery cell 20 includes an end cap 21, a housing 22, an electrode assembly 23, and an isolation assembly 24.

[0169] A pressure relief channel 22a is provided at the bottom of the housing 22 along its height direction. The electrode assembly 23 is disposed inside the housing 22.

[0170] The isolation assembly 24 includes a support member 241, an insulating film 242, and a connecting block 243. The support member 241 is disposed between the bottom of the housing 22 and the electrode assembly 23 and is used to support the electrode assembly 23. The heat-resistant temperature of the support member 241 is greater than 300 degrees Celsius. The material of the support member 241 is PI, and the materials of the insulating film 242 and the connecting block 243 are PP.

[0171] The support member 241 includes a plate body 241a and a spacer block 241b. The plate body 241a has a first surface S1 facing away from the electrode assembly 23 and a second surface S2 facing the electrode assembly 23. A through hole K1 penetrating through the first surface S1 and the second surface S2 is provided on the plate body 241a. The connecting block 243 is adhesively bonded to the first surface S1, and at least a part of the connecting block 243 is used to pass through the through hole K1 and is thermally fused to the insulating film 242. The spacer block 241b is located on the side of the plate body 241a facing away from the electrode assembly 23 and is connected to the first surface S1.

[0172] The end cap 21 covers the opening of the housing 22. The end cap 21 includes an end cap body 211 and an insulating member 212, and the material of the insulating member is PP. The insulating member 212 is disposed on the side of the end cap body 211 facing the electrode assembly 23, and the insulating member 212 is used to be thermally fused to the insulating film 242.

[0173] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be covered within the scope of the claims and the description of the present application. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell (20), characterized in that, Comprising: A housing (22) with a pressure relief channel (22a) provided at the bottom in the height direction of the housing (22); An electrode assembly (23) disposed within the housing (22); and An isolation assembly (24), including a support member (241), an insulating film (242), and a connection block (243). The support member (241) is disposed between the bottom of the housing (22) and the electrode assembly (23) and is used to support the electrode assembly (23). The heat-resistant temperature of the support member (241) is greater than 300 degrees Celsius. The insulating film (242) covers the outer surface of the electrode assembly (23). The connection block (243) is connected to the support member (241), and the connection block (243) is thermally fused to the insulating film (242).

2. The battery cell (20) according to claim 1, characterized in that, The connection block (243) is made of the same material as the insulating film (242).

3. The battery cell (20) according to claim 2, characterized in that, The battery cell (20) further includes: An end cap (21) covering the opening of the housing (22); The end cap (21) includes an end cap body (211) and an insulating member (212). The insulating member (212) is disposed on the side of the end cap body (211) facing the electrode assembly (23), and the insulating member (212) is used to connect to the insulating film (242).

4. The battery cell (20) according to claim 3, characterized in that, The insulating member (212) is made of the same material as the insulating film (242), and the insulating member (212) is thermally fused to the insulating film (242).

5. The battery cell (20) according to claim 3, characterized in that, The connection block (243), the insulating film (242), and the insulating member (212) are made of polypropylene.

6. The battery cell (20) according to claim 1, characterized in that, The support member (241) includes a plate body (241a); The plate body (241a) has a first surface (S1) facing away from the electrode assembly (23) and a second surface (S2) facing the electrode assembly (23). The plate body (241a) is provided with a through hole (K1) penetrating the first surface (S1) and the second surface (S2). The connection block (243) is connected to the first surface (S1), and at least part of the connection block (243) is used to pass through the through hole (K1) and is fixedly connected to the insulating film (242).

7. The battery cell (20) according to claim 6, characterized in that, The connection block (243) includes a first body (243a) and a second body (243b). The first body (243a) is connected to the first surface (S1). One end of the second body (243b) is connected to the first body (243a), and the other end of the second body (243b) is used to pass through the through hole (K1) and is fixedly connected to the insulating film (242); Wherein, the orthographic projection of the first body (243a) on the first surface (S1) completely covers the through hole (K1).

8. The battery cell (20) according to claim 7, characterized in that, The distance between the edge of the first body (243a) and the edge of the through hole (K1) is L1, where L1 ≥ 1 mm.

9. The battery cell (20) according to claim 7, wherein, The gap between the outer surface of the second body (243b) and the inner surface of the through hole (K1) is L2, where L2 ≥ 1 mm.

10. The battery cell (20) according to claim 6, wherein, The height of the connection block (243) protruding from the second surface (S2) is H, wherein 0≤H≤0.1 mm.

11. The battery cell (20) according to claim 6, characterized in that, The support member (241) further includes a cushion block (241b); The cushion block (241b) is located on a side of the plate body (241a) facing away from the electrode assembly (23) and is connected to the first surface (S1).

12. The battery cell (20) according to claim 11, characterized in that, The height of the cushion block (241b) protruding from the first surface (S1) is H1, and the height of the connection block (243) protruding from the first surface (S1) is H2, wherein H1>H2.

13. The battery cell (20) according to claim 12, wherein, H1≥1.5mm, H2≤0.75mm.

14. The battery cell (20) according to claim 6, wherein, The plate body (241a) is also provided with a through hole (K2) penetrating the first surface (S1) and the second surface (S2); the through hole (K2) is arranged opposite to the pressure relief channel (22a).

15. The battery cell (20) according to any one of claims 1-14, characterized in that, The support member (241) is made of polyimide.

16. An assembly method of a battery cell according to any one of claims 1-15, characterized in that, include: Providing a plate body, the plate body having a first surface facing away from the electrode assembly and a second surface facing the electrode assembly; The plate body is provided with a through hole penetrating the first surface and the second surface; Providing a connection block, extending at least a portion of the connection block into the through hole along a first direction, and connecting the connection block to the first surface; providing a supporting force for the connecting block along the first direction; Providing an insulating film, the insulating film facing the second surface, and thermally melting the connecting block to the insulating film; Providing an insulating member, and thermally melting the insulating member and the insulating film; The first direction is the direction from the first surface to the second surface.

17. A hot melt device for implementing the assembly method as described in claim 16, characterized in that, include: A support plate (2000) having a protrusion (2100), wherein the protrusion (2100) is used to provide a supporting force for the connection block (243) along the first direction (F1); A hot melt head (3000) is used to cooperate with the support plate (2000) to hot melt connect the connection block (243) and the insulation film (242).

18. The hot melt device according to claim 17, wherein, The orthographic projection of the hot melt head (3000) on the second surface (S2) completely covers the hot melt area of the connection block (243).

19. The hot melt device according to claim 18, characterized in that, The distance between the edge of the hot melt head (3000) and the edge of the hot melt area is L3, where L3≥5mm.

20. A battery device, characterized in that, The invention comprises a battery cell as claimed in any one of claims 1 to 15.

21. An electrical device, characterized in that, The electrical equipment comprises the battery device as claimed in claim 20, wherein the battery device is used to provide electrical energy.

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