Battery monomer, battery and electric device

Abstract

The utility model provides a single battery, a battery and a power utilization device, the single battery comprises a shell, an electrode assembly and a binding piece, the shell is provided with a cavity, the electrode assembly is arranged in the cavity, and the binding piece surrounds at least part of the shell to provide expansion binding force for the shell so as to inhibit deformation of the shell generated when the single battery is in thermal runaway. And the overall structural strength of the battery monomer can be improved, so that the risk of cracking of the shell due to rapid increase of air pressure in the cavity is reduced, and the reliability of the battery monomer is improved.

Description

Technical Field

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

[0002] Energy conservation and emission reduction are the keys to the sustainable development of the automotive industry. Electric vehicles have become an important part of the sustainable development of the automotive 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] As the energy density of the battery becomes higher and higher, the heat generated by the thermal runaway of the battery cell becomes larger and larger. The existing outer shell of the battery cell is difficult to withstand the temperature and air pressure generated by the thermal runaway, resulting in the situation that the outer shell cracks or even explodes. Therefore, how to improve the structural strength of the battery cell has become an urgent problem to be solved. Summary of the Utility Model

[0004] In view of the above problems, the present application provides a battery cell, a battery and an electrical device, which can reduce the risk of the outer shell cracking due to the rapid increase of the air pressure in the cavity, and improve the reliability of the battery cell.

[0005] In a first aspect, the present application provides a battery cell, including an outer shell, an electrode assembly and a restraint member. The outer shell has a cavity, the electrode assembly is disposed in the cavity, and the restraint member surrounds at least a part of the outer shell to provide an expansion restraint force to the outer shell.

[0006] In the embodiments of the present application, a restraint member is disposed around at least a part of the outer shell, so that when the battery cell undergoes thermal runaway, an expansion restraint force is provided to the outer shell through the restraint member to inhibit the deformation of the outer shell during the thermal runaway of the battery cell, thereby reducing the risk of the outer shell cracking due to the rapid increase of the air pressure in the cavity and improving the reliability of the battery cell.

[0007] In some embodiments, the restraint member encloses a restraint space, the outer shell is disposed in the restraint space, and the restraint member is pressed against the outer shell in the circumferential direction. By disposing the outer shell in the restraint space enclosed by the restraint member, the restraint member can be disposed at least around the circumferential side of the outer shell, so that the outer shell can be circumferentially restrained by the restraint member to strengthen the structural strength of the entire circumference of the external structure of the battery housing.

[0008] In some embodiments, the outer shell includes a housing and an end cover. The housing has a cavity and an opening communicating with the cavity in a first direction. The end cover covers the opening and seals the cavity. The number of the restraint members is more than two, and the more than two restraint members are respectively pressed against the housing and / or the end cover, which can restrain the battery housing and the connection between the housing and the end cover, thereby reducing the risk of the side of the housing exploding or the housing separating from the end cover when the battery cell undergoes thermal runaway and improving the reliability of the battery cell.

[0009] In some embodiments, more than two binding members are distributed at intervals along the first direction and press against the housing in the circumferential direction. That is, the strength of different regions of the housing along the first direction can be bound in the circumferential direction by more than two binding members, so as to reduce the risk of the side of the housing bursting when the battery cell undergoes thermal runaway.

[0010] In some embodiments, more than two binding members are distributed at intervals along the second direction and press against the housing and the end cover in the circumferential direction, and the second direction intersects with the first direction. That is, the strength of different connection regions of the housing and the end cover along the second direction can be bound in the circumferential direction by more than two binding members, so as to reduce the risk of separation between the housing and the end cover when the battery cell undergoes thermal runaway.

[0011] In some embodiments, among more than two binding members, some binding members press against the housing in the circumferential direction, and some binding members press against the housing and the end cover in the circumferential direction. By simultaneously arranging the first binding member and the second binding member on the outer shell, while binding the housing in the circumferential direction, it is also possible to bind the connection between the housing and the end cover in the circumferential direction, so as to reduce the risk of the side of the housing bursting and the separation between the housing and the end cover when the battery cell undergoes thermal runaway, and improve the reliability of the battery cell.

[0012] In some embodiments, the binding member is set as a binding band, and the binding band surrounds to form a binding space and presses against the outer shell in the circumferential direction to perform circumferential binding on the outer shell.

[0013] In some embodiments, the binding band surrounds the outer shell for one week, or the binding band overlaps and surrounds the outer shell for more than two weeks to meet the strength requirements for binding the outer shell and the external structure of the battery cell.

[0014] In some embodiments, the binding member is set as an elastic sleeve, the elastic sleeve includes an end face and a side face surrounding the end face, the end face and the side face enclose a binding space, and the elastic sleeve presses against the outer shell in the circumferential direction through the side face to perform circumferential binding on the outer shell.

[0015] In some embodiments, a pressure relief mechanism is further arranged on the outer shell, the pressure relief mechanism is communicated with the cavity, and the binding member is arranged to avoid the pressure relief mechanism, so that when thermal runaway occurs, the battery cell can perform directional pressure relief through the pressure relief mechanism, improving the reliability of the battery cell.

[0016] In some embodiments, the protruding distance of the surface of the binding member facing away from the cavity relative to the outer shell is 0.2 mm to 1 mm, which can play a certain strength role and can also reduce the occupation of the battery space and improve the energy density of the battery.

[0017] In a second aspect, an embodiment of the present application provides a battery, including the battery cell of the first aspect.

[0018] In a third aspect, an embodiment of the present application provides an electrical device, including the battery of the second aspect, and the battery is used to provide electrical energy.

[0019] For the battery cell according to the embodiment of the present application, a restraint member is disposed around at least a part of the outer shell, so that when the battery cell undergoes thermal runaway, an expansion restraint force is provided to the outer shell through the restraint member to inhibit the deformation of the outer shell during the thermal runaway of the battery cell. Moreover, by making the restraint member and the outer shell composite to form the outer layer structure of the battery cell, the overall structural strength of the battery cell can also be improved, thereby further reducing the risk of the outer shell cracking due to the rapid increase in the air pressure in the cavity and improving the reliability of the battery cell.

[0020] 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 description. Moreover, in order to make the above and other purposes, features, and advantages of the present application more obvious and understandable, the following specifically illustrates the specific embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] By reading the detailed description of the preferred embodiments below, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered to be a limitation of the present application. Moreover, throughout the drawings, the same reference numerals are used to represent the same components. In the drawings:

[0022] Figure 1 is a schematic structural diagram of a vehicle provided by some embodiments of the present application;

[0023] Figure 2 is an exploded view of a battery provided by some embodiments of the present application;

[0024] Figure 3 is a schematic structural diagram of a battery cell provided by some embodiments of the present application;

[0025] Figure 4 is a schematic structural diagram of a battery cell provided by some other embodiments of the present application;

[0026] Figure 5 is a schematic structural diagram of a battery cell provided by some other embodiments of the present application;

[0027] Figure 6 is a schematic structural diagram of a battery cell from another angle provided by some embodiments of the present application.

[0028] The reference numerals in the specific embodiments are as follows:

[0029] 100 battery, 200 controller, 300 motor;

[0030] 10 battery cell, 20 battery box;

[0031] 1 housing, 11 housing body, 12 end cap, 2 restraint member, 2a first restraint member, 2b second restraint member, 3 pressure relief mechanism;

[0032] X second direction, Z first direction. Detailed implementation manners

[0033] The embodiments of the technical solutions of the present application will be described in detail below with reference to the accompanying drawings. The following embodiments are only used to illustrate the technical solutions of the present application more clearly, and therefore are only examples and cannot be used to limit the protection scope of the present application.

[0034] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the embodiments of the present application should be the ordinary meanings understood by those skilled in the art to which the embodiments of the present application belong.

[0035] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the embodiments of the present application.

[0036] In addition, the technical terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. In the description of the embodiments of the present application, "a plurality of" means more than two, unless otherwise specifically defined.

[0037] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, the technical terms "installation", "connection", "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 also 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 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 specific situations.

[0038] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, the first feature being "on" or "under" the second feature may mean that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "below" and "beneath" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the horizontal height of the first feature is lower than that of the second feature.

[0039] At present, from the perspective of the development of the market situation, the application of power batteries is becoming more and more extensive. Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power plants, but also widely used in electric transportation tools such as electric bicycles, electric motorcycles and electric vehicles, as well as in many fields such as military equipment and aerospace. With the continuous expansion of the application fields of power batteries, the market demand is also constantly increasing.

[0040] As the energy density of the battery is getting higher and higher, the heat generated by battery thermal runaway is getting larger and larger. The traditional aluminum shell can basically not withstand the heat generated by thermal runaway and is melted through. Therefore, in the related art, the outer shell of the battery cell is set as a steel shell to withstand part of the energy generated by the thermal runaway of the high energy density battery. However, even if the outer shell of the battery cell is set as a steel shell, there are still some battery cells that cannot withstand the temperature and air pressure generated by thermal runaway, resulting in local cracking or even direct explosion of the outer shell, causing serious consequences.

[0041] Based on the above considerations, in order to reduce the risk of local cracking of the outer shell of the battery cell during thermal runaway, the embodiments of the present application provide a battery cell, in which a restraint member is at least partially surrounded around the outer shell of the battery cell to provide an expansion restraint force to the outer shell, so that the outer shell can withstand the air pressure generated during the thermal runaway of the battery cell.

[0042] The technical solutions described in the embodiments of the present application are applicable to batteries and electrical devices using the batteries.

[0043] The electrical device can be a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, an electric tool, etc. The vehicle can be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle or an extended-range electric vehicle, etc.; the spacecraft includes an airplane, a rocket, a space shuttle, a spaceship, etc.; the electric toy includes a fixed or mobile electric toy, for example, a game console, an electric vehicle toy, an electric ship toy, an electric airplane toy, etc.; the electric tool includes a metal cutting electric tool, a grinding electric tool, an assembly electric tool and a railway electric tool, for example, an electric drill, an electric grinding wheel, an electric wrench, an electric screwdriver, a hammer drill, an impact electric drill, a concrete vibrator, a power planer, etc. The embodiments of the present application do not impose special restrictions on the above electrical devices.

[0044] It should be understood that the technical solutions described in the embodiments of the present application are applicable to all electrical devices including a battery and using the battery. However, for the sake of brevity, the following embodiments will be described by taking an electric vehicle as an example.

[0045] Please refer to Figure 1 , Figure 1 which is a schematic structural diagram of a vehicle provided by some embodiments of the present application.

[0046] A battery 100 is disposed inside the vehicle, and the battery 100 can be disposed at the bottom, the head or the tail of the vehicle. The battery 100 can be used for power supply of the vehicle. For example, the battery 100 can be used as the operating power source of the vehicle. The vehicle may further include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to supply power to the motor 300, for example, for the working power requirements during the start, navigation and driving of the vehicle.

[0047] Please refer to Figure 2 , Figure 2 which is an explosion schematic diagram of the battery 100 provided by some embodiments of the present application.

[0048] The battery 100 mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells 10 to provide a higher voltage and capacity. The battery cell 10 is the smallest unit that makes up the battery 100. The battery 100 generally further includes a battery box 20 for encapsulating one or more battery cells 10. The battery box 20 can prevent liquids or other foreign objects from affecting the charging or discharging of the battery cells 10.

[0049] Multiple battery cells 10 can be connected in series, parallel, or in a combined series-parallel configuration through connecting members. A combined series-parallel configuration means that there are both series and parallel connections among multiple battery cells 10. Multiple battery cells 10 can be directly connected in series, parallel, or in a combined series-parallel configuration together, and then the whole formed by multiple battery cells 10 is accommodated in a battery box 20. Of course, it can also be that multiple battery cells 10 are first connected in series, parallel, or in a combined series-parallel configuration to form a battery 100 in the form of a battery module, and then multiple battery modules are connected in series, parallel, or in a combined series-parallel configuration through connecting members to form a whole and are accommodated in the battery box 20.

[0050] Optionally, the battery cell 10 can be a secondary battery or a primary battery. A secondary battery refers to a battery cell that can have its active materials activated through charging after discharging for continued use. The battery cell includes, but is not limited to, lithium-ion battery cells, sodium-ion battery cells, sodium-lithium-ion battery cells, lithium-metal battery cells, sodium-metal battery cells, lithium-sulfur battery cells, magnesium-ion battery cells, nickel-metal hydride battery cells, nickel-cadmium battery cells, lead-acid battery cells, etc.

[0051] As an example, the battery cell 10 can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes, but is not limited thereto. Prismatic battery cells include square-shell battery cells, blade-shaped battery cells, multi-prismatic batteries, and the multi-prismatic battery is, for example, a hexagonal prism battery, etc.

[0052] Please refer to Figure 3 , Figure 3 which is a schematic structural diagram of the battery cell 10 provided in some embodiments of the present application.

[0053] An embodiment of the present application provides a battery cell 10, including a housing 1, an electrode assembly, and a binding member 2. The housing 1 has a cavity, the electrode assembly is disposed in the cavity, and the binding member 2 surrounds at least a part of the housing 1 to provide an expansion binding force to the housing 1.

[0054] In the battery cell 10 provided by the embodiment of the present application, a binding member 2 is disposed around at least a part of the housing 1. When the battery cell 10 undergoes thermal runaway, the binding member 2 provides an expansion binding force to the housing 1 to inhibit the deformation of the housing 1 during the thermal runaway of the battery cell 10. And by making the binding member 2 and the housing 1 form a composite to form the outer layer structure of the battery cell 10, the overall structural strength of the battery cell 10 can also be improved, thereby further reducing the risk of the housing 1 cracking due to the rapid increase in air pressure in the cavity and improving the reliability of the battery cell 10.

[0055] In the embodiments of the present application, the outer shell 1 is used to form an internal environment, and the formed internal environment can be used to accommodate the electrode assembly, the electrolyte, and other components. The outer shell 1 can be of various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc. Specifically, the shape of the outer shell 1 can be determined according to the specific shape and size of the electrode assembly.

[0056] The outer shell 1 can be made of various materials. Specifically, it can be made of a metal material. For example, the outer shell 1 is set as a steel shell to withstand the temperature generated by the thermal runaway of the battery cell 10, and it can also enable the outer shell 1 itself to have a certain strength to partially withstand the air pressure generated by the thermal runaway of the battery cell 10.

[0057] That the restraint member 2 surrounds at least a part of the outer shell 1 and provides an expansion restraint force to the outer shell 1 means that for some battery cells 10, due to the limited strength of the outer shell 1, when the battery cell 10 undergoes thermal runaway, the outer shell 1 may expand and deform in a direction away from the cavity. Therefore, by arranging the restraint member 2 on the side of the outer shell 1 facing away from the cavity, it can play a certain role in restraining the expansion of the outer shell 1. Moreover, by making the restraint member 2 and the outer shell 1 form the outer layer structure of the battery cell 10, it can also improve the overall structural strength of the battery cell 10, so as to jointly withstand the air pressure generated by the thermal runaway of the battery cell 10 through the combination of the restraint member 2 and the outer shell 1, thereby further reducing the risk of the outer shell 1 cracking and improving the reliability of the battery cell 10.

[0058] Optionally, the restraint member 2 can be made of a non-metallic material, so as to play a role in improving the structural strength through the high-strength non-metallic material while reducing the weight of the battery cell 10, which is more convenient for popularization and application.

[0059] Optionally, the restraint member 2 is an insulating member, that is, the whole restraint member 2 is made of an insulating material, and the insulating material can be rubber, plastic, etc. The restraint member 2 has good insulation effect, so as to reduce the risk of short circuit of the battery cell 10 caused by the restraint member 2.

[0060] In some optional embodiments, the restraint member 2 encloses to form a restraint space, the outer shell 1 is arranged in the restraint space, and the restraint member 2 is pressed against the outer shell 1 along the circumferential direction.

[0061] By arranging the outer shell 1 in the restraint space formed by the enclosure of the restraint member 2, the restraint member 2 can be arranged at least around the circumference of the outer shell 1, so that the outer shell 1 can be circumferentially restrained by the restraint member 2 to strengthen the structural strength of the entire circumference of the external structure of the battery housing 11, which is more convenient for the arrangement of the restraint member 2. Moreover, the restraint member 2 can also press against multiple surfaces of the outer shell 1 along the circumferential direction at the same time, and the restraint force on the outer shell 1 is more uniform and stable.

[0062] Please refer to Figure 3, in some optional embodiments, the number of the binding members 2 is more than two. The more than two binding members 2 respectively surround different regions of the outer shell 1 to locally enhance the strength-weak regions of the outer shell 1 respectively, improve the overall structural strength of the battery cell 10, and further reduce the risk of cracking from the strength-weak regions of the outer shell 1 when the battery cell 10 undergoes thermal runaway.

[0063] Moreover, compared with the way of binding the entire region of the outer shell 1, only separately enhancing the strength-weak regions of the outer shell 1 also reduces the material usage of the binding members 2, reduces the cost, and can also reduce the weight of the battery cell 10.

[0064] For the outer shell 1, it mainly includes a housing 11 and an end cap 12. The housing 11 and the end cap 12 can be independent components. The housing 11 has a cavity to form the internal environment of the electrode assembly, and an opening along the first direction Z is provided on the housing 11.

[0065] The end cap 12 refers to the component that covers the opening of the housing 11 to isolate the internal environment of the battery cell 10 from the external environment. Without limitation, the shape of the end cap 12 can be adapted to the shape of the housing 11 to cooperate with the housing 11. Optionally, the end cap 12 can be made of a material with certain hardness and strength. In this way, the end cap 12 is not easily deformed when being squeezed and collided, enabling the battery cell 10 to have higher structural strength and the safety performance can also be improved.

[0066] In some optional embodiments, more than two binding members 2 respectively press against the housing 11 and / or the end cap 12. Since in practical applications, the strength-weak regions of the outer shell 1 and the main stress regions during thermal runaway are at the battery housing 11 and the connection between the battery housing 11 and the end cap 12, by respectively pressing more than two binding members 2 against the housing 11 and / or the end cap 12, the battery housing 11 and the connection between the housing 11 and the end cap 12 can be bound, thereby reducing the risk of the side of the housing 11 bursting open or the separation of the housing 11 and the end cap 12 when the battery cell 10 undergoes thermal runaway, and improving the reliability of the battery cell 10.

[0067] For the battery cell 10, the specific arrangement position of the binding member 2 can be adjusted according to the actual stress condition of the battery cell 10.

[0068] Please refer to Figure 3 , in some optional embodiments, more than two binding members 2 are spaced apart along the first direction Z and press against the housing 11 in the circumferential direction. That is, the strength of different regions of the housing 11 along the first direction Z can be bound by more than two binding members 2 in the circumferential direction to reduce the risk of the side of the housing 11 bursting open when the battery cell 10 undergoes thermal runaway.

[0069] Among them, more than two binding members 2 can be set to have different structural strengths. For example, they can be set to have different thicknesses or be made of different materials, so as to more specifically provide different expansion binding forces of different magnitudes to different regions of the housing 11 along the first direction Z, thereby improving the overall structural strength of the battery cell 10.

[0070] As an alternative embodiment, the number of the binding members 2 can be set to two and evenly distributed on the housing 11 along the first direction Z. Of course, the number of the binding members 2 can also be set to three, five or even more. The specific number of the binding members 2 can also be adjusted according to the size of each binding member 2 along the first direction Z and the size of the housing 11 along the first direction Z.

[0071] Please refer to Figure 4 , Figure 4 which shows a schematic structural diagram of the battery cell 10 provided in some other embodiments of the present application. In some other alternative embodiments, more than two binding members 2 are spaced apart along the second direction X and are circumferentially pressed against the housing 11 and the end cap 12. The second direction X intersects the first direction Z. That is, more than two binding members 2 can circumferentially bind different connection regions of the housing 11 and the end cap 12 along the second direction X, so as to reduce the risk of separation between the housing 11 and the end cap 12 when the battery cell 10 undergoes thermal runaway.

[0072] As an alternative embodiment, the number of the binding members 2 can be set to two and evenly distributed on the end cap 12 along the second direction X to strengthen the connection between the housing 11 and the end cap 12. Of course, the number of the binding members 2 can also be set to three, five or even more. The specific number of the binding members 2 can also be adjusted according to the size of each binding member 2 along the second direction X and the size of the housing 11 or the end cap 12 along the second direction X.

[0073] Please refer to Figure 5 , Figure 5 which shows a schematic structural diagram of the battery cell 10 provided in some other embodiments of the present application. In some other alternative embodiments, among more than two binding members 2, some binding members 2 are circumferentially pressed against the housing 11, and some binding members 2 are circumferentially pressed against the housing 11 and the end cap 12.

[0074] For the convenience of description, the binding member 2 is divided into a first binding member 2a and a second binding member 2b. The first binding member 2a is circumferentially pressed against the housing 11, and the second binding member 2b is circumferentially pressed against the housing 11 and the end cap 12.

[0075] By simultaneously arranging the first restraint member 2a and the second restraint member 2b on the outer shell 1, while circumferentially restraining the housing 11, it is also possible to circumferentially restrain the connection between the housing 11 and the end cover 12. Thus, when the battery cell 10 undergoes thermal runaway, the risk of the side of the housing 11 bursting open and the separation of the housing 11 from the end cover 12 can be reduced simultaneously, improving the reliability of the battery cell 10.

[0076] Optionally, the number of the first restraint members 2a is more than two, and the two or more first restraint members 2a are spaced apart along the first direction Z, and / or the number of the second restraint members 2b is more than two, and the two or more second restraint members 2b are spaced apart along the second direction X. That is, by increasing the number of the first restraint members 2a and the second restraint members 2b, the expansion restraint force on the housing 11 itself and the connection between the housing 11 and the end cover 12 is further increased, further reducing the risk of the side of the housing 11 bursting open and the separation of the housing 11 from the end cover 12, and improving the reliability of the battery cell 10.

[0077] As an optional embodiment, the number of the first restraint members 2a can be set to two and evenly distributed on the housing 11 along the first direction Z, the number of the second restraint members 2b can also be set to two and evenly distributed on the end cover 12 along the second direction X, and the first restraint members 2a and the second restraint members 2b are arranged intersectingly.

[0078] Please refer to Figure 6 , Figure 6 FIG. shows a schematic structural view of the battery cell 10 provided by some embodiments of the present application from another angle. In some optional embodiments, a pressure relief mechanism 3 is further arranged on the outer shell 1. The pressure relief mechanism 3 is communicated with the cavity, and the restraint member 2 is arranged to avoid the pressure relief mechanism 3.

[0079] By arranging the pressure relief mechanism 3 on the outer shell 1, when the internal pressure of the cavity increases rapidly due to the thermal runaway of the battery cell 10, the pressure can be released through the pressure relief mechanism 3, reducing the risk of explosion of the battery cell 10. And by arranging the restraint member 2 to avoid the pressure relief mechanism 3, the influence of the arrangement of the restraint member 2 on the pressure relief mechanism 3 can be reduced, enabling the pressure relief mechanism 3 to be normally opened for pressure relief.

[0080] It can be understood that by at least partially surrounding and arranging the restraint member 2 on the outer shell 1, the compressive capacity of each part of the external structure of the battery cell 10 should be greater than the opening pressure of the pressure relief mechanism 3, so that when thermal runaway occurs, the battery cell 10 can be directionally pressure-relieved through the pressure relief mechanism 3, improving the reliability of the battery cell 10.

[0081] Optionally, the pressure relief mechanism 3 can be set as an explosion-proof valve.

[0082] Please refer to Figure 6In order to make the restraining member 2 enclose a restraining space, in some embodiments, the restraining member 2 is configured as a restraining belt, which surrounds the restraining space and presses against the outer shell 1 along the annular direction.

[0083] That is, as an optional implementation, the restraint member 2 can be set as a restraint belt, so that the restraint belt is wound around the peripheral side of the shell 1 of the battery cell 10 in the circumferential direction to circumferentially restrain the shell 1. The restraint belt should be arranged away from the pressure relief mechanism 3 to increase the overall structural strength of the battery cell 10 while achieving directional pressure relief.

[0084] When the restraining member 2 is configured as a restraining belt, it can be wrapped around the outer shell 1 for one or more times according to the structural strength requirements of the battery cell 10. The number of wrappings can be adjusted according to the actual structure of the battery cell 10, and can meet the restraint requirements of the outer shell 1 and the strength requirements of the external structure of the battery cell 10.

[0085] Optionally, the material of the restraint belt can be set to carbon fiber, nylon, polypropylene, etc. By setting the restraint belt to carbon fiber filaments, nylon tie, etc., it can reduce the weight of the battery cell 10 while enhancing the strength, which is more convenient for practical application.

[0086] It is understandable that, in addition to configuring the restraint 2 as a restraint belt, the restraint 2 may also be configured in other conventional alternatives, such as configuring the restraint 2 as a frame, and configuring the frame around the battery cell 10 to constrain the housing 1 in the circumferential direction.

[0087] In addition, in addition to setting the restraint 2 as a restraint belt, in other embodiments, the restraint 2 can be set as an elastic sleeve, the elastic sleeve includes an end face and a side face arranged around the end face, the end face and the side face enclose a restraint space, and the elastic sleeve is pressed against the outer shell 1 along the annular direction through the side face.

[0088] That is, as an optional implementation, the restraint 2 can also be set as an elastic sleeve, which includes an end face and a side face. Taking the elastic sleeve as an example, which is pressed against the shell 11 along the circumferential direction, the end face of the elastic sleeve can be matched with the end cover 12 of the outer shell 1, and the side face of the elastic sleeve can be matched with the shell 11 of the outer shell 1 to provide expansion restraint force to the shell 11.

[0089] It can be understood that when the pressure relief mechanism 3 on the outer shell 1 is located in the restraining space, a vent can be opened at a corresponding position on the end face and / or side of the elastic sleeve to expose the pressure relief mechanism 3 through the vent, thereby increasing the overall structural strength of the battery cell 10 while achieving directional pressure relief.

[0090] In some optional embodiments, the protrusion distance of the surface of the restraining member 2 facing away from the cavity relative to the housing 1 is 0.2 mm to 1 mm.

[0091] It should be noted that the protruding distance of the surface of the restraint member 2 on the side away from the cavity relative to the outer shell 1 is the thickness of the restraint member 2. Among them, the outer shell 1 includes a housing 11 and an end cap 12. Therefore, for the housing 11, it refers to the protruding distance of the surface of the restraint member 2 on the side away from the cavity relative to the housing 11. And since the end cap 12 includes a cover body and functional components such as electrode terminals and liquid injection holes provided on the cover body, for the end cap 12, it refers to the protruding distance of the surface of the restraint member 2 on the side away from the cavity relative to the cover body.

[0092] By making the thickness of the restraint member 2 greater than or equal to 0.2 mm, it can play a certain strength role to better meet the structural strength requirements of the battery cell 10. And by making the thickness of the restraint member 2 less than or equal to 1 mm, it can also reduce the occupation of the battery space and improve the energy density of the battery 100.

[0093] Please refer to Figures 1 to 6 , taking a specific embodiment as an example below, the structure of the battery cell 10 in the embodiments of the present application will be described.

[0094] The battery cell 10 in the embodiments of the present application includes an outer shell 1, an electrode assembly, a restraint member 2, and a pressure relief mechanism 3 provided on the outer shell 1. The outer shell 1 includes a housing 11 and an end cap 12. The restraint member 2 is set as a restraint belt, and the restraint belt is arranged to avoid the pressure relief mechanism 3 and wound around the circumference of the outer shell 1.

[0095] Specifically, the restraint member 2 includes a first restraint member 2a and a second restraint member 2b. The number of the first restraint members 2a is two, and the two first restraint members 2a are arranged at intervals along the first direction Z and press against the housing 11 in the circumferential direction. The number of the second restraint members 2b is two, and the two second restraint members 2b are arranged at intervals along the second direction X and press against the housing 11 and the end cap 12 in the circumferential direction. By providing the first restraint member 2a and the second restraint member 2b, while being able to circumferentially restrain the housing 11, it can also circumferentially restrain the connection between the housing 11 and the end cap 12, thereby enhancing the overall structural strength of the battery cell 10, reducing the risk of the side of the housing 11 exploding and the separation of the housing 11 and the end cap 12, and realizing directional pressure relief.

[0096] According to some embodiments of the present application, the present application also provides a battery 100, including the battery cell 10 of any of the above solutions.

[0097] According to some embodiments of the present application, the present application also provides an electrical device, including the battery 100 of any of the above solutions, and the battery 100 is used to provide electrical energy for the electrical device.

[0098] The electrical device can be any of the foregoing devices or systems using the battery 100.

[0099] 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 various 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, characterized in that: include: a housing having a cavity; An electrode assembly, disposed in the cavity; A restraint member surrounds at least a portion of the housing to provide an expansion restraint force to the housing.

2. The battery cell according to claim 1, characterized in that: The binding member encloses a binding space, the outer shell is arranged in the binding space, and the binding member is arranged to press against the outer shell along the circumferential direction.

3. The battery cell according to claim 2, characterized in that: The shell includes a shell and an end cover, the shell has the cavity and an opening connected to the cavity along a first direction, the end cover covers the opening and seals the cavity, the number of the restraining members is more than two, and the more than two restraining members are respectively pressed against the shell and / or the end cover.

4. The battery cell according to claim 3, characterized in that: The two or more restraining members are distributed at intervals along the first direction and press against the shell along the circumferential direction.

5. The battery cell according to claim 3, characterized in that: The two or more restraining members are distributed at intervals along a second direction and are arranged to press against the shell and the end cover along the annular direction, and the second direction intersects with the first direction.

6. The battery cell according to claim 3, characterized in that: Among the two or more restraining members, some of the restraining members are arranged to press against the shell along the annular direction, and some of the restraining members are arranged to press against the shell and the end cover along the annular direction.

7. The battery cell according to any one of claims 2 to 6, characterized in that: The binding member is configured as a binding belt, which surrounds the binding space and is pressed against the outer shell along the circumferential direction.

8. The battery cell according to claim 7, characterized in that: The restraining belt surrounds the outer shell once, or the restraining belt overlaps and surrounds the outer shell for more than two times.

9. The battery cell according to any one of claims 2 to 6, characterized in that: The restraining member is configured as an elastic sleeve, the elastic sleeve comprises an end face and a side face arranged around the end face, the end face and the side face enclose the restraining space, and the elastic sleeve is pressed against the outer shell along the circumferential direction through the side face.

10. The battery cell according to any one of claims 1 to 6, characterized in that: The shell is also provided with a pressure relief mechanism, which is communicated with the cavity, and the restraining member is arranged to avoid the pressure relief mechanism.

11. The battery cell according to any one of claims 1 to 6, characterized in that: The protrusion distance of the surface of the restraining member on one side away from the cavity relative to the shell is 0.2mm-1mm.

12. A battery, characterized in that: The invention comprises a battery cell as claimed in any one of claims 1 to 11.

13. An electrical device, characterized in that: Comprising the battery of claim 12, the battery being used to provide electrical energy.

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