Battery cell, cover assembly, battery, power consuming device, method and apparatus

Abstract

The present application relates to a battery cell, a cover assembly, a battery, a power consumption device, a method, and an apparatus, the battery cell comprising: an electrode assembly; and an outer casing for accommodating the electrode assembly, the wall of the outer casing including a main body and a fastener, the fastener having a recess communicating with the outside, the recess being recessed from the inner surface of the fastener facing the electrode assembly in a direction away from the electrode assembly; and a vent element covering the recess and venting the gas to the outside of the outer casing through the recess when the gas pressure inside the outer casing reaches a threshold, the bottom wall of the recess having a protrusion extending toward the electrode assembly, the protrusion being attached to the vent element and configured to limit deformation of the vent element along the thickness direction of the wall. The embodiments of the present application can mitigate battery safety issues caused by exhaust.

Description

[Technical field]

[0001] The present application relates to the field of battery technology, and in particular to battery cells, cover assemblies, batteries, power consuming devices, methods and apparatus. [Background technology]

[0002] Rechargeable battery cells have the advantages of high energy density, high power density, many repeated uses, long storage time, etc., and are therefore widely used in electric vehicles. At present, the exhaust safety of battery cells restricts the development of battery cells, so technological research related to the safety performance of battery cells has become one of the research topics. Summary of the Invention

[0003] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present application provide a battery cell, a cover assembly, a battery, a power consuming device, a method and an apparatus, in which the battery cell can mitigate battery safety issues due to exhaust gases.

[0004] According to a first aspect, the present application provides a battery cell. The battery cell includes an electrode assembly, an outer casing, and a ventilation part. The outer casing is used to house the electrode assembly, and the wall of the outer casing includes a main body and a fixture, and the fixture is provided with a recess communicating with the outside, and the recess is recessed from an inner surface of the fixture facing the electrode assembly in a direction away from the electrode assembly. The ventilation part covers the recess, and is used to exhaust the gas to the outside of the outer casing through the recess when the gas pressure inside the outer casing reaches a threshold value. Here, a protrusion extending toward the electrode assembly is provided on a bottom wall of the recess, and the protrusion is attached to the ventilation part and configured to limit deformation of the ventilation part along the thickness direction of the wall.

[0005] In the technical solution of the embodiment of the present application, the wall of the outer casing includes a body and a fixing device, the fixing device has a recess communicating with the outside, the recess is recessed from the inner surface of the fixing device facing the electrode assembly in a direction away from the electrode assembly, and the ventilation part is installed to cover the recess, and through the ventilation part, when the gas pressure inside the outer casing reaches a threshold, the gas can be discharged to the outside of the outer casing to meet the exhaust demand. The bottom wall of the recess is provided with a protrusion extending toward the electrode assembly, and the protrusion is attached to the ventilation part to provide support for the ventilation part on the side away from the electrode assembly in the thickness direction, so as to limit the deformation of the ventilation part along the thickness direction of the wall due to the action of the gas inside the outer casing, and to mitigate the deterioration of the ventilation part.

[0006] In some embodiments, an accommodating cavity communicating with the outside is formed between the outer peripheral wall of the protrusion and the inner peripheral wall of the recess, a first through hole is provided in the bottom wall of the recess, and the first through hole is configured to be gas-communicating with the internal space of the battery cell through the accommodating cavity. By forming an accommodating cavity communicating with the outside between the outer peripheral wall of the protrusion and the inner peripheral wall of the recess, and providing the first through hole in the bottom wall of the recess, it is possible to ensure the exhaust demand of the gas inside the battery cell passing through the accommodating cavity and the first through hole, and it is also possible to facilitate the installation of the protrusion, and the protrusion can be attached to a ventilation part, limiting the deformation of the ventilation part in the thickness direction.

[0007] In some embodiments, the number of the first through holes is a plurality of holes, and the plurality of first through holes are spaced apart from one another. By providing a plurality of first through holes, it is possible to ensure an exhaust rate and improve the safety performance of the battery cell.

[0008] In some embodiments, the protrusion includes a first protrusion, and the receiving cavity communicating with the outside is formed between an outer peripheral wall of the first protrusion and an inner peripheral wall of the recess. With the above arrangement, the protrusion can be attached to the ventilation component by the first protrusion, and the gas in the battery cell can be discharged through the receiving cavity formed between the first protrusion and the recess, so that the deformation of the ventilation component in the thickness direction can be limited while satisfying the exhaust demand.

[0009] In some embodiments, the protrusion includes a first protrusion and a second protrusion, the second protrusion is disposed around the first protrusion and spaced apart from the first protrusion, the accommodating cavity communicating with the outside is formed between the outer peripheral wall of the first protrusion and the inner peripheral wall of the second protrusion, and the accommodating cavity communicating with the outside is formed between the outer peripheral wall of the second protrusion and the inner peripheral wall of the recess. With the above arrangement, the protrusion can be attached to the ventilating part by the first protrusion and the second protrusion at the same time, effectively restricting the deformation of the ventilating part in the thickness direction, and the gas in the battery cell can be discharged through the accommodating cavity between the first protrusion and the second protrusion and the accommodating cavity between the second protrusion and the recess, ensuring the exhaust demand of the battery cell and improving the safety performance of the battery cell.

[0010] In some embodiments, the number of the second protrusions is two or more, and the two or more second protrusions are spaced apart and coaxially arranged, and the receiving cavity communicating with the outside is formed between two adjacent second protrusions. By the above arrangement, each second protrusion is attached to the ventilation part, the attachment area between the protrusion and the ventilation part can be increased, and the probability of deformation of the ventilation part in the thickness direction can be reduced. And, the receiving cavity communicating with the outside is formed between the first protrusion and the second protrusion, between the second protrusion and the second protrusion, and between the second protrusion and the recess, which can improve the exhaust rate and improve the safety of the battery cell.

[0011] In some embodiments, the fastener includes a second through hole for receiving the fastener, and the fastener is used to connect the ventilation component and the main body. This allows the fastener and the main body to be installed separately, which is advantageous for forming structures such as recesses and protrusions.

[0012] In some embodiments, the second through hole includes a first hole portion and a second hole portion in an axial direction thereof, the radial dimension of the first hole portion is greater than the radial dimension of the second hole portion, and a transition surface for supporting the fastener is connected between the first hole portion and the second hole portion, where the axial direction is parallel to the thickness direction of the wall portion. The second through hole adopts a stepped hole type, so that the transition surface can support and position the fastener, and facilitate the installation and connection between the fastener and the body portion.

[0013] In some embodiments, the second bore portion is located between the first bore portion and the electrode assembly, and in the axial direction, a surface of the fastener facing the electrode assembly abuts the transition surface, whereby the transition surface can provide support to the surface of the fastener facing the electrode assembly, ensuring positioning needs for the fastener and facilitating connection between the fastener and the body portion.

[0014] In some embodiments, the first hole portion is located between the second hole portion and the electrode assembly, the surface of the fixture facing away from the electrode assembly abuts the transition surface, and the orthogonal projection of each of the first through holes is located inside the orthogonal projection of the hole wall of the second hole portion in the axial direction. With the above arrangement, the transition surface provides support to the surface of the fixture facing away from the electrode assembly, ensuring the positioning needs of the fixture, and the orthogonal projection of each of the first through holes is located inside the orthogonal projection of the hole wall of the second hole portion, preventing the transition surface from blocking the first through holes and ensuring smooth exhaust of the battery cells.

[0015] In some embodiments, the first hole portion is located between the second hole portion and the electrode assembly, and the surface of the fixture facing away from the electrode assembly abuts the transition surface, and the second through hole further includes a third hole portion, which is formed extending from the transition surface along the axial direction away from the first hole portion, and the radial dimension of the third hole portion is smaller than the radial dimension of the first hole portion and larger than the radial dimension of the second hole portion. In the axial direction, the orthogonal projection of each of the first through holes is located inside the orthogonal projection of the hole wall of the third hole portion. With the above arrangement, the transition surface can provide support to the surface of the fixture facing away from the electrode assembly, and ensure the positioning needs of the fixture. At the same time, the arrangement of the third hole portion can avoid the transition surface from blocking the first through hole when the radial dimension of the second hole portion is relatively small, and ensure the smooth exhaust of the battery cell.

[0016] In some embodiments, the fastener includes a connecting portion and a mounting portion, the connecting portion is protruding from an outer wall of the mounting portion, the connecting portion is used to connect to the main body portion, and the mounting portion is used to connect to the ventilation component. The fastener adopts the above-mentioned structural form, which can facilitate the installation of the ventilation component and ensure the connection demand with the main body portion.

[0017] In some embodiments, the connection portion is welded to the body portion, the attachment portion is installed to protrude from the connection portion toward the side where the electrode assembly is located along the thickness direction, and the ventilation part is connected to an end surface of the attachment portion facing the electrode assembly. The connection strength between the connection portion and the body portion can be ensured by adopting a welding connection method. The attachment portion is installed to protrude from the connection portion toward the side where the electrode assembly is located, and the ventilation part is connected to an end surface of the attachment portion facing the electrode assembly, so that the distance between the welding positions of the ventilation part, the connection portion, and the body portion is increased, and it is possible to prevent the ventilation part from being damaged by heat generated when the connection portion and the body portion are welded to each other, or to prevent the connection strength between the ventilation part and the attachment portion from being affected.

[0018] In some embodiments, a gap is formed between the outer wall of the mounting part and the hole wall of the second through hole, so that the ventilation part and the hole wall of the second through hole are spaced apart from each other, thereby preventing heat generated during the welding connection between the connection part and the body part from being transferred from the body part to the ventilation part, thereby preventing the ventilation part from being damaged or affecting the connection strength between the ventilation part and the mounting part.

[0019] In some embodiments, a support is provided in the receiving cavity for supporting the vent component, and the gas can be discharged from the first through hole through the support. By providing a support in the receiving cavity, it is advantageous that the support can provide further support to the vent component, limiting deformation of the vent component in the thickness direction.

[0020] In some embodiments, the support is connected to the wall surface surrounding the receiving cavity by chemical bonding, which can ensure the connection strength between the support and the wall surface surrounding the receiving cavity and prevent the ventilation component from being affected by the separation between the support and the wall surface of the receiving cavity.

[0021] In some embodiments, the ventilation part is connected to the end surface of the protrusion by chemical bonding, which can ensure the connection strength between the ventilation part and the protrusion, reduce the impact on the performance of the ventilation part, and improve the safety performance of the battery cell while meeting the exhaust demand.

[0022] In some embodiments, the enclosure includes a housing and a cover assembly, the housing having an opening, the cover assembly being disposed to close the opening, and one of the housing and the cover assembly including the wall, whereby a fastener can be disposed on the housing or, of course, on the cover assembly, either of which can meet the ventilation needs.

[0023] In some embodiments, the cover assembly includes the wall portion, and the battery cell further includes an insulating material for separating the cover assembly from the electrode assembly, and the insulating material is provided with a third through hole for communicating with the recess. The above-mentioned installation can allow a fastener to be installed in the cover assembly, so that the cover assembly has an exhaust function. At the same time, the installation of the insulating material can avoid contact short between the electrode assembly and the cover assembly and improve the safety performance of the battery cell, while the correspondingly installed third through hole can facilitate the exhaust of gas inside the battery cell.

[0024] In some embodiments, the number of the third through holes is a plurality of, and the plurality of the third through holes are spaced apart from each other. By providing the plurality of the third through holes, the gas discharge rate in the battery cell can be ensured, and the safety performance of the battery cell can be improved.

[0025] According to a second aspect, the present application provides a cover assembly for a battery cell including an electrode assembly, the cover assembly including a cover plate, a wall portion of the cover plate including a main body portion and a fastener, the fastener being provided with a recess communicating with the outside, the recess being recessed from an inner surface of the fastener facing the electrode assembly in a direction away from the electrode assembly, and a ventilating part covering the recess and discharging the gas to the outside of the battery cell through the recess when a gas pressure inside the battery cell reaches a threshold value, the bottom wall of the recess being provided with a protrusion extending toward the electrode assembly, the protrusion being attached to the ventilating part and configured to limit deformation of the ventilating part along a thickness direction of the wall portion.

[0026] In the technical solution of the embodiment of the present application, the wall of the cover plate includes a body and a fastener, the fastener is provided with a recess communicating with the outside, the recess is recessed from the inner surface of the fastener facing the electrode assembly in a direction away from the electrode assembly, the ventilation part is provided to cover the recess, and the ventilation part can exhaust the gas to the outside of the outer casing when the gas pressure inside the battery cell reaches a threshold value through the ventilation part to meet the exhaust demand. The bottom wall of the recess is provided with a protrusion extending toward the electrode assembly, and the protrusion is attached to the ventilation part to provide support for the ventilation part on the side away from the electrode assembly in the thickness direction, so as to limit the deformation of the ventilation part along the thickness direction of the wall due to the action of the gas inside the battery cell, and to mitigate the deterioration of the ventilation part.

[0027] According to a third aspect, the present application provides a battery including the above-mentioned battery cell.

[0028] According to a fourth aspect, the present application provides a power consuming device including a battery as described above for use in providing electrical energy.

[0029] According to a fifth aspect, the present application provides a method for manufacturing a battery cell, the method comprising the steps of: providing a housing having an opening; providing an electrode assembly and enclosing said electrode assembly within said housing; providing a cover assembly, and molding a battery cell by covering the opening with the cover assembly, the cover assembly including a cover plate and a ventilation part, a wall portion of the cover plate including a main body portion and a fastener, the fastener having a recess communicating with the outside, the recess being recessed from an inner surface of the fastener facing the electrode assembly in a direction away from the electrode assembly, the ventilation part covering the recess, the ventilation part being used to exhaust the gas to the outside of the battery cell through the recess when a gas pressure inside the battery cell reaches a threshold, wherein a bottom wall of the recess is provided with a protrusion extending toward the electrode assembly, the protrusion being attached to the ventilation part and configured to limit deformation of the ventilation part along a thickness direction of the wall portion.

[0030] According to a sixth aspect, the present application provides a battery cell manufacturing apparatus, the manufacturing apparatus comprising: a first assembly device configured to provide a housing having an opening; a second assembly device configured to provide an electrode assembly and place the electrode assembly within the housing; and a third assembly device configured to provide a cover assembly and to cover the opening with the cover assembly to form a battery cell, the cover assembly including a cover plate and a ventilation part, a wall portion of the cover plate including a main body portion and a fastener, the fastener having a recess communicating with the outside, the recess being recessed from an inner surface of the fastener facing the electrode assembly in a direction away from the electrode assembly, the ventilation part covering the recess, the ventilation part being used to exhaust the gas to the outside of the battery cell through the recess when a gas pressure inside the battery cell reaches a threshold, wherein a bottom wall of the recess is provided with a protrusion extending toward the electrode assembly, and the protrusion is attached to the ventilation part and configured to limit deformation of the ventilation part along a thickness direction of the wall portion.

[0031] The above description is only an outline of the technical solution of the present application, which can be implemented in accordance with the content of the specification in order to make the technical means of the present application more clearly known, and in order to make the above description and other objectives, features and advantages of the present application more obvious and understandable, the following particularly cites specific embodiments of the present application as its description. [Brief description of the drawings]

[0032] In order to more clearly explain the technical solutions of the embodiments of the present application, the following briefly introduces the drawings that need to be used in the embodiments of the present application. It is obvious that the drawings described below are only some embodiments of the present application, and those skilled in the art can also obtain other drawings based on the drawings without exerting creative efforts. [Figure 1] 1 is a structural schematic diagram of a vehicle according to some embodiments of the present application. [Diagram 2] FIG. 2 is an exploded view of a battery according to some embodiments of the present application. [Diagram 3] FIG. 2 is an exploded structural schematic diagram of a battery cell according to some embodiments of the present application. [Figure 4] FIG. 2 is a plan view of a battery cell according to some embodiments of the present application. [Diagram 5] FIG. 5 is a local cross-sectional view taken along the AA direction in FIG. [Figure 6] FIG. 6 is an enlarged view of B in FIG. [Figure 7] FIG. 2 is an exploded view of a local structure of a battery cell according to some embodiments of the present application. [Figure 8] FIG. 2 is a schematic diagram of the local structure of a battery cell according to some embodiments of the present application. [Figure 9] FIG. 2 is a schematic diagram of a local structure of a battery cell according to some other embodiments of the present application. [Figure 10] FIG. 2 is a schematic diagram of a local structure of a battery cell according to still another embodiment of the present application. [Figure 11] 10A-10C are local cross-sectional views of battery cells according to further some embodiments of the present application. [Figure 12] 10A-10C are local cross-sectional views of battery cells according to further some embodiments of the present application. [Figure 13] 10A-10C are local cross-sectional views of battery cells according to further some embodiments of the present application. [Figure 14] 1A-1C are schematic diagrams of local structures of battery cells according to further some embodiments of the present application. [Figure 15] 10A-10C are local cross-sectional views of battery cells according to further some embodiments of the present application. [Figure 16] 1 is a flow diagram of a method for manufacturing a battery cell according to some embodiments of the present application. In the drawings, like elements are described with like reference numerals. The drawings are not drawn to scale. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0033] The following describes in detail the embodiments of the technical solution of the present application in conjunction with the drawings. The following embodiments are only used to more clearly explain the technical solution of the present application, and are only used as examples, which cannot limit the protection scope of the present application.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art of the present application, and the terms used herein are merely for describing specific embodiments and are not intended to limit the present application, and the terms "including" and "having" and any variations thereof in the specification and claims of this application and the description of the drawings above are intended to cover the non-exclusive "including".

[0035] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are used only to distinguish different objects, and cannot be understood as indicating or implying a relative importance, or implicitly indicating the number, a particular order, or a hierarchical relationship of the indicated technical features. In the description of the embodiments of the present application, "plurality" means two or more, unless expressly and specifically limited.

[0036] An "embodiment" referred to in this specification means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present application. The phrase's appearances in various places in the specification do not necessarily all refer to the same embodiment, nor are they mutually exclusive independent or alternative embodiments. Those skilled in the art can explicitly and implicitly understand that the embodiments described in this specification can be combined with other embodiments.

[0037] In the description of the embodiments of this application, the term "and / or" merely describes the relationship between related objects and indicates that three relationships may exist, for example, A and / or B may represent three cases: A alone, a combination of A and B, and B alone. In addition, the character " / " in this specification generally indicates that the related objects before and after are in an "or" relationship.

[0038] In describing the embodiments of the present application, the term "plurality" refers to two or more (including two); similarly, "multiple sets" refers to two or more (including two sets); and "multiple sheets" refers to two or more (including two sheets).

[0039] In the description of the embodiments of the present application, the orientations or positional relationships indicated by technical terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial direction", "radial direction", "circumferential direction", etc. are orientations or positional relationships shown based on the drawings, and are intended only to facilitate the description of the embodiments of the present application and to simplify the description, and do not indicate or imply that the devices or elements mentioned must have a specific orientation and be configured and operated in a specific orientation, and therefore should not be understood as limitations on the embodiments of the present application.

[0040] In the description of the embodiments of the present application, unless otherwise clearly defined or limited, the technical terms "attached", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, may be a fixed connection, a detachable connection, or may be integrated, may be a mechanical connection, may be an electrical connection, may be a direct connection, may be an indirect connection through an intermediate medium, may be a communication between two elements, or may be a relationship of interaction between two elements. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present application according to the specific circumstances.

[0041] At present, in view of the development of the market situation, the application of power batteries is becoming more and more widespread. Power batteries are not only applied to energy storage power systems such as hydroelectric, thermal, wind and solar power stations, but also widely applied to electric transportation tools such as electric bicycles, electric motorcycles, electric cars, and military equipment, aerospace, and other fields. With the continuous expansion of the application fields of power batteries, the market demand for them is also constantly increasing.

[0042] The inventors have noticed that during the use of a battery, after many charge and discharge cycles, side reactions will occur, gas will continue to be generated, and a certain air pressure will exist inside the battery cell, and as the air pressure rises, the gas between the plates cannot be expelled in a timely manner, which will affect the absorption and release of lithium ions, and even lead to the risk of lithium precipitation. Therefore, the battery cell outer casing is equipped with a ventilation part, which, in addition to having an explosion-proof function, can be gradually infiltrated and vented, thereby reducing the air pressure inside the battery cell and reducing the risk of lithium precipitation.

[0043] The inventors discovered that when the air pressure inside the battery cell reaches a preset threshold, gas is released from the battery cell through the ventilation part, and in the process of being released to the outside, the gas acts on the ventilation part, making the ventilation part more likely to deform, resulting in the formation of a gap between the ventilation part and the outer casing, making it easier for the electrolyte inside the battery cell to adhere to the ventilation part, and causing the ventilation part to swell with long-term use, accelerating the deterioration of the ventilation part and posing safety concerns for the battery cell.

[0044] In order to alleviate the problem of the ventilation component being deformed by the action of gas inside the battery cell, the applicant's research has discovered that providing a support on the side of the ventilation component facing away from the electrode assembly can resist the force acting on the ventilation component during gas discharge, reduce deformation of the ventilation component, and mitigate deterioration of the ventilation component.

[0045] In view of the above, in order to alleviate the problem of deformation and deterioration of the ventilation parts during use of the battery cell, the inventor conducted extensive research and eventually designed a battery cell that provides support to the ventilation parts, thereby reducing deformation of the ventilation parts and ensuring the safety performance of the battery cell.

[0046] The battery cells disclosed in the embodiments of the present application can be used in, but are not limited to, power consumption devices such as vehicles, ships, or aircraft, etc. The battery cells, batteries, etc. disclosed in the present application can be used to configure the power supply system of the power consumption device, which is advantageous in reducing deformation and deterioration of ventilation parts, and improves the stability of battery performance and battery life.

[0047] The embodiments of the present application provide a power consuming device that uses a battery as a power source. The power consuming device may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric car, a steamship, a spacecraft, etc. Here, the electric toy may include a stationary or mobile electric toy, such as a game console, an electric car toy, an electric steamship toy, an electric plane toy, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, a spaceship, etc.

[0048] For convenience of explanation, the following embodiment will be described by taking as an example that the power consuming device in one embodiment of the present application is a vehicle 1000.

[0049] Referring to FIG. 1, FIG. 1 is a structural schematic diagram of a vehicle 1000 according to some embodiments of the present application. The vehicle 1000 may be a gasoline vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or a range extender vehicle, etc. A battery 100 is installed inside the vehicle 1000, and the battery 100 may be installed at the bottom, head or tail of the vehicle 1000. The battery 100 may be used to supply power to the vehicle 1000, for example, the battery 100 may be an operating power source for the vehicle 1000. The vehicle 1000 may further include a controller 200 and a motor 300, and the controller 200 is used to control the battery 100 to supply power to the motor 300, for example, to be used for starting the vehicle 1000, and for operating power consumption needs during navigation and running.

[0050] In some embodiments of the present application, the battery 100 is not only used as an operating power source for the vehicle 1000, but can also provide driving power to the vehicle 1000 in place of, or in place of, gasoline or natural gas as a driving power source for the vehicle 1000.

[0051] Referring to FIG. 2, FIG. 2 is an exploded view of a battery 100 according to some embodiments of the present application. The battery 100 includes a housing 10 and a battery cell 20, and the battery cell 20 is accommodated in the housing 10. Here, the housing 10 is used to provide an accommodation space for the battery cell 20, and the housing 10 may adopt various structures. In some embodiments, the housing 10 may include a first part 11 and a second part 12, and the first part 11 and the second part 12 are covered with each other, and the first part 11 and the second part 12 jointly define an accommodation space for accommodating the battery cell 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, and the first part 11 is covered on the open side of the second part 12, so that the first part 11 and the second part 12 jointly define the accommodation space. The first part 11 and the second part 12 may each have a hollow structure with one side open, and the open side of the first part 11 is covered by the open side of the second part 12. Of course, the housing 10 formed by the first part 11 and the second part 12 may have various shapes, such as a cylinder or a rectangular parallelepiped.

[0052] In the battery 100, the battery cell 20 may be multiple, and the multiple battery cells 20 may be connected in series, parallel, or series-parallel. The series-parallel connection means that the multiple battery cells 20 may be connected in series or in parallel. The multiple battery cells 20 may be directly connected in series, parallel, or series-parallel, and the entire battery cell 20 may be housed in the housing 10. Of course, the battery 100 may be formed by first connecting the multiple battery cells 20 in series, parallel, or series-parallel to form a battery module, and then connecting the multiple battery modules in series, parallel, or series-parallel to form an integrated battery module and housed in the housing 10. The battery 100 may further include other structures, and for example, the battery 100 may further include a bus bar member for achieving electrical connection between the multiple battery cells 20.

[0053] Here, each battery cell 20 may be a secondary battery or a primary battery, and may be, but is not limited to, a lithium-sulfur battery, a sodium ion battery, or a magnesium ion battery. The battery cell 20 may have a cylindrical shape, a flat shape, a rectangular shape, or other shapes.

[0054] Referring to Fig. 3, Fig. 3 is an exploded structural schematic diagram of a battery cell 20 according to some embodiments of the present application. The battery cell 20 is the smallest unit constituting a battery. As shown in Fig. 3, the battery cell 20 includes a cover assembly 21, a housing 22, an electrode assembly 23, and other functional members.

[0055] The cover assembly 21 is a member that covers the opening of the housing 22 and isolates the internal environment of the battery cell 20 from the external environment. Without being limited thereto, the shape of the cover assembly 21 may be adapted to the shape of the housing 22 so as to fit the housing 22. Optionally, the cover assembly 21 may be made of a material (e.g., an aluminum alloy) having a certain hardness and strength, so that the cover assembly 21 is less likely to be deformed when subjected to a pressing impact, the battery cell 20 may have higher structural strength, and safety performance may be improved. The cover assembly 21 may include functional members such as an electrode terminal 21a, a cover plate 21b, and the like. The electrode terminal 21a may be used to electrically connect to the electrode assembly 23 to output or input electrical energy of the battery cell 20. In some embodiments, the cover assembly 21 may further be provided with a pressure relief mechanism for releasing internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold value. The material of the cover assembly 21 may be various, for example, copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application are not particularly limited thereto. In some embodiments, an insulating material 24 may be further installed inside the cover assembly 21, and the insulating material 24 may be used to isolate the electrode assembly 23 and the cover assembly 21 in the housing 22 so as to reduce the risk of short circuit. Exemplarily, the insulating material 24 may be plastic, rubber, etc.

[0056] The housing 22 and the cover assembly 21 jointly form the outer casing of the battery cell 100, and the housing 22 is an assembly that forms an internal environment of the battery cell 20 by mating with the cover assembly 21, and the formed internal environment may be used to accommodate the electrode assembly 23, the electrolyte, and other components. The housing 22 and the cover assembly 21 may be independent members, and an opening is provided in the housing 22, and the cover assembly 21 covers the opening at the opening to form the internal environment of the battery cell 20. Without being limited thereto, the cover assembly 21 and the housing 22 may be integrated, and specifically, the cover assembly 21 and the housing 22 may first form a common connection surface before other components are inserted into the case, and when it is necessary to package the inside of the housing 22, the cover assembly 21 may cover the housing 22. The housing 22 may have various shapes and dimensions, such as a rectangular parallelepiped shape, a cylindrical shape, a hexagonal prism shape, etc. Specifically, the shape of the housing 22 may be determined according to the specific shape and size of the electrode assembly 23. The housing 22 may be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present application is not particularly limited in this regard.

[0057] The electrode assembly 23 is a component where an electrochemical reaction occurs in the battery cell 100. One or more electrode assemblies 23 may be included in the housing 22. The electrode assembly 23 is mainly formed by winding or stacking a positive electrode plate and a negative electrode plate, and a separator is generally provided between the positive electrode plate and the negative electrode plate. The parts of the positive electrode plate and the negative electrode plate that have active materials constitute the body of the electrode assembly, and the parts of the positive electrode plate and the negative electrode plate that do not have active materials constitute the tabs 231, respectively. The positive electrode tabs and the negative electrode tabs may be jointly located at one end of the body, or may be located at both ends of the body. During charging and discharging of the battery, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tabs 231 are connected to the electrode terminal 21a to form a current circuit.

[0058] According to some embodiments of the present application, with reference to FIG. 3 and further with reference to FIG. 4 to FIG. 6, FIG. 4 is a top view of a battery cell 20 of some embodiments of the present application, FIG. 5 is a local cross-sectional view along the AA direction in FIG. 4, and FIG. 6 is an enlarged view of B in FIG. 5.

[0059] The embodiment of the present application provides a battery cell 20 including an outer casing, an electrode assembly 23, and a ventilation part 25. The outer casing is used to house the electrode assembly 23, and a wall part 210 of the outer casing includes a main body part 211 and a fixing part 212. The fixing part 212 is provided with a recess 2121 communicating with the outside, and the recess 2121 is recessed in a direction away from the electrode assembly 23 from the inner surface of the fixing part 212 facing the electrode assembly 23. The ventilation part 25 covers the recess 2121, and is used to exhaust gas to the outside of the outer casing through the recess 2121 when the gas pressure inside the outer casing reaches a threshold value. Here, a protrusion 2122 extending toward the electrode assembly 23 is provided on the bottom wall 2121a of the recess 2121, and the protrusion 2122 is attached to the ventilation part 25 and configured to limit deformation of the ventilation part 25 along the thickness direction X of the wall part 210.

[0060] The outer casing has a housing 22 and a cover assembly 21, the housing 22 has an opening, the cover assembly 21 is installed to seal the opening, and one wall 210 of the housing 22 and the cover assembly 21 includes a fastener 212, and the wall of the housing 22 may include the fastener 212, or the wall of the cover assembly 21 may include the fastener 212. The cover assembly 21 covers the opening of the housing 22 to form an internal environment of the battery cell 20 and is used to accommodate the electrode assembly 23, and the wall 210 is a part of the side wall of the outer casing for surrounding and forming the internal environment.

[0061] The fastener 212 may have a regular geometric shape, such as a circle, an ellipse, or a polygon, or may have an irregular geometric shape. The fastener 212 includes a portion through which gas can pass so that gas inside the battery cell 20 can pass and be exhausted from the battery cell 20.

[0062] The main body 211 is the portion of the wall 210 other than the fastener 212, and both the main body 211 and the fastener 212 may be of an integral structure or may be of a separate structure.

[0063] The recess 2121 is recessed from the inner surface of the fixing device 212 facing the electrode assembly 23 in a direction away from the electrode assembly 23, and the recess 2121 has a bottom wall 2121a and an inner wall 2121b. In the thickness direction X, the thickness of the bottom wall 2121a is smaller than the thickness of the wall portion 210. The recess 2121 is surrounded by the bottom wall 2121a and the inner wall 2121b to form a recessed cavity, and the protrusion 2122 is located within the recessed cavity.

[0064] The recess 2121 being in communication with the outside means that the recess 2121 is in communication with a portion of the battery cell 20 other than the outer casing.

[0065] The protrusion 2122 is a projection extending from the bottom wall 2121a of the recess 2121 toward the electrode assembly 23, and the protrusion 2122 protrudes from the bottom wall 2121a of the recess 2121 in the thickness direction X.

[0066] The orthogonal projection of the ventilation part 25 in the thickness direction X covers the recess 2121, so that the fluid must pass through the ventilation part 25 when flowing through the recess 2121. Through the ventilation part 25, the gas inside the battery cell 20 can be circulated to the outside, and water vapor and the like outside the battery cell 20 can be prevented from entering the inside of the battery cell 20.

[0067] The protrusion 2122 and the ventilation component 25 may be in contact with each other but not connected, and of course the protrusion 2122 may be in contact with and connected to the ventilation component 25, for example by employing a chemical bonding connection, an adhesive connection, etc., and the protrusion 2122 may provide support to the side of the ventilation component 25 facing away from the electrode assembly 23.

[0068] In the technical solution of the embodiment of the present application, the wall portion 210 of the outer casing includes a main body portion 211 and a fixing device 212, and a recess 2121 communicating with the outside is provided in the fixing device 212, and the recess 2121 is recessed from the inner surface of the fixing device 212 facing the electrode assembly 23 in a direction away from the electrode assembly 23, and the ventilation part 25 covers the recess 2121, so that when the gas pressure inside the outer casing reaches a threshold value, the gas can be discharged to the outside of the outer casing through the ventilation part 25 to meet the exhaust demand. A protrusion 2122 extending toward the electrode assembly 23 is provided on the bottom wall 2121a of the recess 2121. By attaching the protrusion 2122 to the ventilation part 25, support is provided to the side of the ventilation part 25 that faces away from the electrode assembly 23 in the thickness direction X, and deformation of the ventilation part 25 along the thickness direction X of the wall part 210 due to the action of the internal gas of the battery cell 20 can be limited, and deterioration of the ventilation part 25 can be mitigated.

[0069] Referring to Figures 3 to 6 and further to Figure 7, Figure 7 is an exploded view of the local structure of the battery cell 20 of some embodiments of the present application, and according to some embodiments of the present application, optionally, an accommodating cavity 2124 communicating with the outside is formed between the outer peripheral wall 2122c of the protrusion 2122 and the inner peripheral wall 2121b of the recess 2121, and a first through hole 2123 configured to be gas-communicative with the internal space of the battery cell 20 via the accommodating cavity 2124 is provided in the bottom wall 2121a of the recess 2121.

[0070] The wall surface of the protrusion 2122 that is installed facing the inner wall 2121b of the recess 2121 is the outer wall 2122c of the protrusion 2122, and the outer wall 2122c of the protrusion 2122 and the inner wall 2121b of the recess 2121 are both annular surfaces, which may be circular annular surfaces or polygonal annular surfaces, and the shapes of the two may be the same, for example, the outer wall 2122c of the protrusion 2122 and the inner wall 2121b of the recess 2121 can both be circular annular, or of course, they may be different, for example, one of the outer wall 2122c of the protrusion 2122 and the inner wall 2121b of the recess 2121 can be a circular annular surface and the other a polygonal annular surface. The first through-hole 2123 penetrates the bottom wall 2121a of the recess 2121 in the thickness direction X, and is connected to the accommodating cavity 2124, so that gas inside the battery cell 20 can pass through the ventilation part 25 into the accommodating cavity 2124 and be discharged to the outside of the battery cell 20 through the first through-hole 2123. The shape of the first through-hole 2123 is not specifically limited, and may be a circular hole, an elliptical hole, a polygonal hole, or an irregular hole as long as it can meet the demand for gas discharge.

[0071] By forming a accommodating cavity 2124 communicating with the outside between the outer peripheral wall 2122c of the protrusion 2122 and the inner peripheral wall 2121b of the recess 2121, and providing a first through hole 2123 in the bottom wall 2121a of the recess 2121, it is possible to ensure the exhaust demand for gas inside the battery cell 20 through the accommodating cavity 2124 and the first through hole 2123, and also to facilitate installation of the protrusion 2122, whereby the protrusion 2122 is attached to the ventilation part 25 and deformation of the ventilation part 25 in the thickness direction X can be limited.

[0072] According to some embodiments of the present application, optionally, the number of the first through holes 2123 is multiple, and the multiple first through holes 2123 are distributed at intervals.

[0073] The number of first through holes 2123 may be two, three, or even more. The multiple first through holes 2123 may be arranged regularly or irregularly. The distance between two adjacent first through holes 2123 may be equal, or of course may not be equal. The shape and dimensions of each first through hole 2123 may be the same or different.

[0074] By providing a plurality of first through holes 2123, the exhaust rate can be ensured and the safety performance of the battery cell 20 can be improved.

[0075] Optionally, the plurality of first through holes 2123 are spaced apart and uniformly disposed to ensure uniformity of exhaust. Optionally, at least some of the plurality of first through holes 2123 may be spaced apart and uniformly distributed along a circular locus.

[0076] 3 to 7, and further referring to FIG. 8, FIG. 8 is a schematic diagram of a local structure of a battery cell 20 according to some embodiments of the present application. According to some embodiments of the present application, the protrusion 2122 optionally includes a first protrusion 2122a, and a receiving cavity 2124 communicating with the outside is formed between an outer peripheral wall of the first protrusion 2122a and an inner peripheral wall 2121b of the recess 2121.

[0077] The first protrusion 2122a may be a columnar body or, of course, may be an annular body, and the ventilation part 25 is attached to the surface of the first protrusion 2122a facing the electrode assembly 23. Gas inside the battery cell 20 enters the accommodation cavity 2124 formed between the first protrusion 2122a and the inner peripheral wall 2121b of the recess 2121 through the ventilation part 25, and is then discharged to the outside of the battery cell 20 through the first through-hole 2123.

[0078] With the above-mentioned installation, the protrusion 2122 can be attached to the ventilation part 25 by the first protrusion 2122a, and the gas in the battery cell 20 can be discharged through the accommodating cavity 2124 formed between the first protrusion 2122a and the recess 2121, thereby limiting the deformation of the ventilation part 25 in the thickness direction X while satisfying the exhaust demand.

[0079] As shown in Fig. 9, Fig. 9 is a schematic diagram of a local structure of a battery cell 20 of another embodiment of the present application. According to some embodiments of the present application, optionally, the protrusion 2122 includes a first protrusion 2122a and a second protrusion 2122b, the second protrusion 2122b surrounds the first protrusion 2122a and is spaced apart from the first protrusion 2122a, and an accommodating cavity 2124 communicating with the outside is formed between the outer circumferential wall of the first protrusion 2122a and the inner circumferential wall of the second protrusion 2122b, and an accommodating cavity 2124 communicating with the outside is formed between the outer circumferential wall of the second protrusion 2122b and the inner circumferential wall 2121b of the recess 2121.

[0080] The first protrusion 2122a may be a columnar body or an annular body, and the second protrusion 2122b may be an annular body, and the ventilation part 25 is attached to the surfaces of the first protrusion 2122a and the second protrusion 2122b that face the electrode assembly 23. First through holes 2123 are provided in the bottom wall 2121a of the recess 2121, in the region between the outer peripheral wall of the first protrusion 2122a and the inner peripheral wall of the second protrusion 2122b, and in the region between the outer peripheral wall of the second protrusion 2122b and the inner peripheral wall 2121b of the recess 2121.

[0081] With the above-mentioned installation, the protrusion 2122 is simultaneously attached to the ventilation part 25 by the first protrusion 2122a and the second protrusion 2122b, which can effectively limit the deformation in the thickness direction X of the ventilation part 25. At the same time, the gas in the battery cell 20 is discharged through the receiving cavity 2124 between the first protrusion 2122a and the second protrusion 2122b, and the receiving cavity 2124 between the second protrusion 2122b and the recess 2121, which can ensure the exhaust demand of the battery cell 20 and improve the safety performance of the battery cell 20.

[0082] Optionally, each of the receiving cavities 2124 is an annular cavity, and the number of the first through holes 2123 communicating with each of the receiving cavities 2124 is plural and distributed at intervals along the annular locus of the annular cavity, which is advantageous for the exhaust of gas.

[0083] As shown in Fig. 10, Fig. 10 is a schematic diagram of a local structure of a battery cell 20 according to some other embodiments of the present application. According to some embodiments of the present application, optionally, the number of the second protrusions 2122b is two or more, and the two or more second protrusions 2122b are spaced apart and coaxially arranged, and a receiving cavity 2124 communicating with the outside is formed between two adjacent second protrusions 2122b.

[0084] The number of the second protrusions 2122b may be two, three or even more, the second protrusions 2122b are annular bodies, the two or more second protrusions 2122b are distributed at intervals in a direction perpendicular to the thickness direction X, and the axial direction of each second protrusion 2122b is parallel to the thickness direction X. A first through hole 2123 is provided in the bottom wall 2121a of the recess 2121 in a region between two adjacent second protrusions 2122b.

[0085] With the above-mentioned installation, each second protrusion 2122b is attached to the ventilation part 25, increasing the attachment area of ​​the protrusion 2122 and the ventilation part 25, and reducing the probability of deformation in the thickness direction X of the ventilation part 25. Furthermore, between the first protrusion 2122a and the second protrusion 2122b, between the second protrusion 2122b and the second protrusion 2122b, and between the second protrusion 2122b and the recess 2121, a storage cavity 2124 communicating with the outside is formed, which improves the exhaust rate and makes the battery cell 20 safer.

[0086] Continuing to refer to Figures 3 to 10, according to some embodiments of the present application, optionally, the fastener 212 includes a second through hole 2111, which is used to accommodate the fastener 212, and the fastener 212 is used to connect the ventilation part 25 and the main body portion 211.

[0087] The fastener 212 and the main body 211 may be installed separately, the fastener 212 may be completely located in the second through hole 2111 of the main body 211, or at least a portion of the fastener 212 may be installed to protrude beyond the main body 211 in the thickness direction X. The fastener 212 and the main body 211 may be connected in a fixed manner or in a detachable manner. The ventilation part 25 is connected to the main body 211 by the fastener 212.

[0088] By installing as described above, the fixture 212 and the main body 211 can be installed separately, which is advantageous in forming structures such as the recess 2121 and the protrusion 2122 of the fixture 212.

[0089] According to some embodiments of the present application, optionally, the second through hole 2111 includes a first hole portion 2111a and a second hole portion 2111b in its axial direction, the radial dimension of the first hole portion 2111a is larger than the radial dimension of the second hole portion 2111b, and a transition surface 2111c for supporting the fastener 212 is connected between the first hole portion 2111a and the second hole portion 2111b, where the axial direction is parallel to the thickness direction X of the wall portion 210.

[0090] The entire second through hole 2111 may be a stepped hole. There is no specific limitation on the dimensional ratio of the first hole portion 2111a and the second hole portion 2111b in the axial direction, and the shapes of the first hole portion 2111a and the second hole portion 2111b in the orthogonal projection in the axial direction may be the same, for example, both may be circular or polygonal, and of course, in some examples, the shapes of the first hole portion 2111a and the second hole portion 2111b in the orthogonal projection in the axial direction may be different, for example, one of the orthogonal projections may be circular and the other may be polygonal. The entire second through hole 2111 is connected to the inside of the battery cell 20 in the thickness direction X.

[0091] When the orthogonal projections in the axial direction of the first hole portion 2111a and the second hole portion 2111b are both circular, the radial direction Y is the extension direction of the diameter of the circular orthogonal projections.

[0092] When the orthogonal projection in the axial direction of at least one of the first hole portion 2111a and the second hole portion 2111b is non-circular, for example when the orthogonal projection is polygonal, the radial direction Y is a direction perpendicular to the axial direction, and the radial direction Y may be, for example, the extension direction of a line between the center of the orthogonal projection in the thickness direction X of the second through hole 2111 and a point on the outer contour line of the orthogonal projection.

[0093] The second through hole 2111 adopts the form of a stepped hole, so that the transition surface 2111c can support the fastener 212, regulate the position of the fastener 212, and facilitate the installation and connection between the fastener 212 and the main body 211.

[0094] According to some embodiments of the present application, optionally, the second hole portion 2111b is located between the first hole portion 2111a and the electrode assembly 23, and in the axial direction, the surface of the fixture 212 facing the electrode assembly 23 abuts against the transition surface 2111c.

[0095] A portion of the surface of the fixing device 212 facing away from the electrode assembly 23 may protrude beyond the first hole portion 2111a, and of course may be located within the first hole portion 2111a. When located within the first hole portion 2111a, the space occupied by the battery cell 20 can be reduced and its capacity density can be improved.

[0096] The surface of the fixture 212 facing the electrode assembly 23 contacts only the transition surface 2111c, and the transition surface 2111c can provide support for the fixture 212 in a direction away from the electrode assembly 23. Of course, the surface of the fixture 212 facing the electrode assembly 23 can contact and connect with the transition surface 2111c, as long as the connection between the fixture 212 and the main body 211 is ensured.

[0097] With the above arrangement, the transition surface 2111c can provide support to the surface of the fixture 212 facing the electrode assembly 23, ensure positioning needs for the fixture 212, and facilitate connection between the fixture 212 and the main body portion 211.

[0098] 11, which is a local cross-sectional view of a battery cell 20 according to some further embodiments of the present application. According to some embodiments of the present application, optionally, the first hole portion 2111a is located between the second hole portion 2111b and the electrode assembly 23, the surface of the fixture 212 facing away from the electrode assembly 23 is abutted against the transition surface 2111c, and in the axial direction, the orthogonal projection of each first through hole 2123 is located inside the orthogonal projection of the hole wall of the second hole portion 2111b.

[0099] A portion of the surface of the fixture 212 facing the electrode assembly 23 may protrude beyond the first hole portion 2111a, or may of course be located within the first hole portion 2111a.

[0100] The surface of the fixture 212 facing away from the electrode assembly 23 contacts the fixing surface, and the supporting surface provides support to the fixture 212 in the direction facing away from the electrode assembly 23. Of course, the surface of the fixture 212 facing away from the electrode assembly 23 may contact and connect only to the transition surface 2111c, as long as the connection requirement between the fixture 212 and the main body 211 is ensured.

[0101] The orthogonal projection in the axial direction of the hole wall of the second hole portion 2111b is annular, and the orthogonal projection of each of the first through holes 2123 is located inside the annular orthogonal projection of the second hole portion 2111b.

[0102] With the above-mentioned installation, the transition surface 2111c provides support to the surface of the fastener 212 facing away from the electrode assembly 23, thereby ensuring the positioning needs of the fastener 212; and by positioning the orthogonal projection of each first through hole 2123 inside the orthogonal projection of the hole wall of the second hole portion 2111b, the transition surface 2111c is prevented from blocking the first through holes 2123, and smooth exhaust of the battery cells 20 is ensured.

[0103] 12, which is a local cross-sectional view of a battery cell 20 according to some further embodiments of the present application. According to some embodiments of the present application, optionally, the first hole portion 2111a is located between the second hole portion 2111b and the electrode assembly 23, and the surface of the fastener 212 facing away from the electrode assembly 23 is abutted against the transition surface 2111c, and the second through hole 2111 further includes a third hole portion 2111d, which is formed extending from the transition surface 2111c along the axial direction to the side facing away from the first hole portion 2111a, and the radial dimension of the third hole portion 2111d is smaller than the radial dimension of the first hole portion 2111a and larger than the radial Y dimension of the second hole portion 2111b. In the axial direction, the orthogonal projection of each first through hole 2123 is located inside the orthogonal projection of the hole wall of the third hole portion 2111d.

[0104] With the above-mentioned arrangement, the transition surface 2111c provides support to the surface of the fastener 212 that is away from the electrode assembly 23, and ensures the positioning needs of the fastener 212. At the same time, with the arrangement of the third hole portion 2111d, when the radial dimension of the second hole portion 2111b is relatively small, the transition surface 2111c is prevented from blocking the first through-hole 2123, and smooth exhaust of the battery cell 20 can be ensured.

[0105] Continuing to refer to Figures 6 to 12, according to some embodiments of the present application, optionally, the fastener 212 includes a connection portion 212a and an attachment portion 212b, the connection portion 212a protruding from and connected to the outer wall of the attachment portion 212b, the connection portion 212a being used to connect to the main body portion 211, and the attachment portion 212b being used to connect to the ventilation part 25.

[0106] The mounting portion 212b may be columnar, and may have the same or different length dimension as the fixing portion in the thickness direction X. One end of the mounting portion 212b and one end of the connecting portion 212a in the thickness direction X may be flush with each other.

[0107] The above-mentioned structural form of the fastener 212 can facilitate the installation of the ventilation part 25 and ensure the connection requirements with the main body 211 .

[0108] According to some embodiments of the present application, optionally, the connection portion 212a is welded to the main body portion 211 and is installed such that the mounting portion 212b protrudes from the connection portion 212a toward the side where the electrode assembly 23 is located along the thickness direction X, and the ventilation part 25 is connected to the end surface of the mounting portion 212b facing the electrode assembly 23.

[0109] The welding position of the connecting portion 212a and the main body portion 211 may be set according to needs, and in some optional examples, one end of the connecting portion 212a in the thickness direction X may be welded to the main body portion 211.

[0110] The length dimension of the mounting portion 212b in the thickness direction X is greater than the length dimension of the connection portion 212a in the thickness direction X, and the ventilation part 25 is connected to the end surface of the mounting portion 212b facing the electrode assembly 23.

[0111] The strength of the connection between the connection part 212a and the main body part 211 can be ensured by adopting a welding connection method between them. However, by installing the attachment part 212b so as to protrude from the connection part 212a toward the side where the electrode assembly 23 is located, and connecting the ventilation part 25 to the end face of the attachment part 212b facing the electrode assembly 23, the distance between the welding positions of the ventilation part 25, the connection part 212a, and the main body part 211 can be increased, and it is possible to prevent the ventilation part 25 from being damaged by heat generated when the connection part 212a and the main body part 211 are welded together, or to prevent an effect on the connection strength between the ventilation part 25 and the attachment part 212b.

[0112] According to some embodiments of the present application, optionally, a gap 2125 is formed between the outer wall of the mounting portion 212b and the hole wall of the second through hole 2111 so that the ventilation part 25 and the hole wall of the second through hole 2111 are spaced apart.

[0113] In the radial direction Y of the second through hole 2111, a gap 2125 is formed between the outer wall of the mounting portion 212b and the hole wall of the second through hole 2111, and since the ventilation part 25 is attached to the mounting portion 212b and its edge does not exceed the outer wall of the mounting portion 212b, a gap is similarly formed between the ventilation part 25 and the hole wall of the second through hole 2111.

[0114] By the above installation, heat generated during the welding connection between the connection portion 212a and the main body portion 211 is not transferred from the main body portion 211 to the ventilation part 25, which prevents the ventilation part 25 from being damaged or affects the connection strength between the ventilation part 25 and the mounting portion 212b.

[0115] 13 and 14, Fig. 13 is a local cross-sectional view of the battery cell 20 of some further embodiments of the present application, and Fig. 14 is a local structural schematic view of the battery cell 20 of some further embodiments of the present application. According to some embodiments of the present application, optionally, a support 26 for supporting the ventilation part 25 is installed in the receiving cavity 2124, and the gas can be discharged from the first through hole 2123 through the support 26.

[0116] The support material 26 has a certain hardness and can support the ventilation part 25, and the support material 26 is breathable, so that the gas entering the accommodating cavity 2124 in the battery cell 20 can be smoothly discharged to the outside of the battery cell 20 without being blocked by the support material 26.

[0117] By locating the support 26 within the receiving cavity 2124, the support 26 advantageously provides further support to the ventilation element 25, limiting deformation of the ventilation element 25 in the thickness direction X.

[0118] According to some embodiments of the present application, optionally, the support 26 and the surrounding walls forming the receiving cavity 2124 are connected by a chemical bond.

[0119] The above installation ensures the connection strength between the support material 26 and the wall surface surrounding the storage cavity 2124, and prevents the ventilation part 25 from being affected by separation between the support material 26 and the wall surface of the storage cavity 2124.

[0120] According to some embodiments of the present application, optionally, the end faces of the vent element 25 and the protrusion 2122 are connected by chemical bonding.

[0121] By the above-mentioned installation, the connection strength between the ventilation part 25 and the protrusion 2122 can be ensured and the impact on the performance of the ventilation part 25 can be reduced, thereby improving the safety performance of the battery cell 20 while satisfying the exhaust demand.

[0122] According to some embodiments of the present application, optionally, one of the housing 22 and the cover assembly 21 includes a wall 210. The housing 22 may include the wall 210, or the cover assembly 21 may include the wall 210. When the cover assembly 21 includes the wall 210, the cover assembly 21 may be a component part of the battery cell 20, or may be produced, sold, etc. as an independent part.

[0123] 3 and 15, which is a local cross-sectional view of the battery cell 20 according to some further embodiments of the present application. According to some embodiments of the present application, optionally, the cover assembly 21 includes a wall portion 210, and the battery cell 20 further includes an insulating material 24 for separating the cover assembly 21 and the electrode assembly 23, and the insulating material 24 is provided with a third through hole 241 for communicating with the recess 2121.

[0124] The fastener 212 is installed on the wall portion 210 included in the cover assembly 21, and the battery cell 20 is located between the cover assembly 21 and the electrode assembly 23. The number of the third through holes 241 in the insulating material 24 is not specifically limited, and may be one or more. The number may be the same as the number of the first through holes 2123, or may be different. In the thickness direction X, the orthogonal projection of the third through hole 241 and the orthogonal projection of the first through hole 2123 may overlap, partially overlap, or be offset from each other.

[0125] Through the above installation, the fastener 212 is installed in the cover assembly 21, and the cover assembly 21 can have an exhaust function. At the same time, the installation of the insulating material 24 can avoid contact short between the electrode assembly 23 and the cover assembly 21 and improve the safety performance of the battery cell 20, while the correspondingly installed third through hole 241 can facilitate the exhaust of gas inside the battery cell 20.

[0126] According to some embodiments of the present application, optionally, the number of the third through holes 241 is multiple, and the multiple third through holes 241 are spaced apart from each other.

[0127] The number of third through holes 241 may be two, three, or even more. The multiple third through holes 241 may be arranged regularly or irregularly. The distance between two adjacent third through holes 241 may be equal, or of course may not be equal. The shape and dimensions of each third through hole 241 may be the same or different.

[0128] By providing a plurality of third through holes 241, the rate at which gas is discharged from within the battery cell 20 can be ensured, and the safety performance of the battery cell 20 can be improved.

[0129] 3 through 15, and further reference to FIG. 16, FIG. 16 is a schematic flow diagram of a method for manufacturing a battery cell 20 according to some embodiments of the present application.

[0130] According to another aspect, an embodiment of the present application provides a method for manufacturing the battery cell 20. The method includes the following steps.

[0131] S100, providing a housing 22 having an opening.

[0132] S200, providing an electrode assembly 23 and placing the electrode assembly 23 in a housing 22;

[0133] S300 provides a cover assembly 21, and places the cover assembly 21 over the opening to form a battery cell 20. The cover assembly 21 includes a cover plate 21b and a ventilation part 25. The wall part 210 of the cover plate 21b includes a body part 211 and a fixture 212. The fixture 212 is provided with a recess 2121 communicating with the outside, and the recess 2121 is recessed in a direction away from the electrode assembly 23 from the inner surface of the fixture 212 facing the electrode assembly 23. The ventilation part 25 covers the recess 2121, and is used to exhaust gas to the outside of the battery cell 20 through the recess 2121 when the gas pressure inside the battery cell 20 reaches a threshold value. Here, a protrusion 2122 extending in the direction of the electrode assembly 23 is provided on the bottom wall 2121a of the recess 2121, and the protrusion 2122 is attached to the ventilation part 25 and configured to limit deformation of the ventilation part 25 along the thickness direction X of the wall part 210.

[0134] The manufacturing method of the battery cell 20 according to the embodiments of the present application may be used to manufacture the battery cell 20 according to the above-mentioned embodiments, and the manufactured battery cell 20 can be attached to the ventilation part 25 by the protrusion 2122, thereby providing support to the side of the ventilation part 25 away from the electrode assembly 23 in the thickness direction X, limiting deformation of the ventilation part 25 along the thickness direction X of the wall part 210 due to the action of the internal gas of the battery cell 20, mitigating deterioration of the ventilation part 25, and achieving higher safety performance.

[0135] According to yet another aspect, an embodiment of the present application provides a manufacturing apparatus for a battery cell 20. The manufacturing apparatus includes: a first assembly device configured to provide a housing 22 having an opening; a second assembly device configured to provide an electrode assembly 23 and place the electrode assembly 23 within the housing 22; A third assembly device configured to provide a cover assembly 21 and to cover an opening with the cover assembly 21 to form a battery cell 20, the cover assembly 21 including a cover plate 21b and a ventilation part 25, the wall portion 210 of the cover plate 21b including a main body portion 211 and a fastener 212, the fastener 212 being provided with a recess 2121 communicating with the outside, the recess 2121 being provided on an inner surface of the fastener 212 facing the electrode assembly 23 in a direction away from the electrode assembly 23. The ventilation part 25 is recessed and covers the recess 2121, and the ventilation part 25 is used to discharge gas to the outside of the battery cell 20 through the recess 2121 when the gas pressure inside the battery cell 20 reaches a threshold value, wherein a bottom wall 2121a of the recess 2121 is provided with a protrusion 2122 extending toward the electrode assembly 23, and the protrusion 2122 includes a third assembly device attached to the ventilation part 25 and configured to limit deformation of the ventilation part 25 along the thickness direction X of the wall portion 210.

[0136] The manufacturing method of the battery cell 20 according to the embodiments of the present application may be used to manufacture the battery cell 20 according to the above-mentioned embodiments, and the manufactured battery cell 20 can be attached to the ventilation part 25 by the protrusion 2122, thereby providing support to the side of the ventilation part 25 away from the electrode assembly 23 in the thickness direction X, limiting deformation of the ventilation part 25 along the thickness direction X of the wall part 210 due to the action of the internal gas of the battery cell 20, mitigating deterioration of the ventilation part 25, and achieving higher safety performance.

[0137] Although the present application has been described with reference to the preferred embodiments, various modifications may be made thereto and equivalents may be substituted for the components without departing from the scope of the present application. In particular, unless there is a structural contradiction, each technical feature mentioned in each embodiment may be combined in any manner. The present application is not limited to the specific embodiments disclosed in the specification, but includes all technical solutions falling within the scope of the claims. [Explanation of symbols]

[0138] Reference numbers in the detailed description of the invention are as follows: 1000-vehicle, 100-battery, 200-controller, 300-motor, 10-casing, 11-first part, 12-second part, 20-battery cell, 21-cover assembly, 21a-electrode terminal, 21b-cover plate, 22-housing, 210-wall portion, 211-main body portion, 2111-second through hole, 2111a-first hole portion, 2111b-second hole portion, 2111c-transition surface, 2111d-third hole portion, 212-fixing tool, 212a-connection portion, 212b-mounting portion, 2121-recess, 2121a-bottom wall, 2121b-inner wall, 2122-protrusion, 2122a-first protrusion, 2122b-second protrusion, 2122c-outer wall, 2123-first through hole, 2124-receiving cavity, 2125-gap, 23-electrode assembly, 231-tab, 24-insulation material, 241-third through hole, 25-ventilation part, 26-support material, X-thickness direction, Y-radial direction.

Claims

1. A battery cell, An electrode assembly; an outer casing for accommodating the electrode assembly, the wall of the outer casing including a main body and a fixture, the fixture being provided with a recess communicating with the outside, the recess being recessed from an inner surface of the fixture facing the electrode assembly in a direction away from the electrode assembly; a ventilation part that is provided between the electrode assembly and the fixing device, covers the recess from the electrode assembly side, and exhausts the gas to the outside of the outer casing through the recess when the gas pressure inside the outer casing reaches a threshold value; Including, a bottom wall of the recess is provided with a protrusion extending toward the electrode assembly, the protrusion being attached to the ventilation part so as to limit deformation of the ventilation part along a thickness direction of the wall part; Battery cell.

2. 2. The battery cell according to claim 1, wherein an accommodating cavity communicating with the outside is formed between an outer peripheral wall of the protrusion and an inner peripheral wall of the recess, and a first through hole is provided in a bottom wall of the recess, and the first through hole is configured to be gas-communicating with an internal space of the battery cell via the accommodating cavity.

3. The battery cell according to claim 2 , wherein the number of the first through holes is a plurality, and the plurality of first through holes are distributed at intervals.

4. The battery cell according to claim 2 or 3, wherein the protruding portion includes a first protrusion, and the accommodating cavity communicating with the outside is formed between an outer peripheral wall of the first protrusion and an inner peripheral wall of the recess.

5. 4. The battery cell of claim 2 or 3, wherein the protrusion includes a first protrusion and a second protrusion, the second protrusion circumnavigates the first protrusion and is spaced apart from the first protrusion, the accommodating cavity communicating with the outside is formed between an outer peripheral wall of the first protrusion and an inner peripheral wall of the second protrusion, and the accommodating cavity communicating with the outside is formed between an outer peripheral wall of the second protrusion and an inner peripheral wall of the recess.

6. 6. The battery cell according to claim 5, wherein the number of the second protrusions is two or more, the two or more second protrusions are arranged coaxially with a space between them, and the accommodating cavity communicating with the outside is formed between two adjacent second protrusions.

7. 7. The battery cell according to claim 2, wherein the main body portion includes a second through hole, the second through hole is used to accommodate the fastener, and the fastener is used to connect the ventilation part and the main body portion.

8. 8. The battery cell of claim 7, wherein the second through hole includes a first hole portion and a second hole portion in an axial direction of the second through hole, a radial dimension of the first hole portion is greater than a radial dimension of the second hole portion, a transition surface for supporting the fastener is connected between the first hole portion and the second hole portion, and the axial direction is parallel to a thickness direction of the wall portion.

9. 9. The battery cell of claim 8, wherein the second hole portion is located between the first hole portion and the electrode assembly, and a surface of the fastener facing the electrode assembly in the axial direction abuts the transition surface.

10. 9. The battery cell of claim 8, wherein the first hole portion is located between the second hole portion and the electrode assembly, a surface of the fastener facing away from the electrode assembly abuts the transition surface, and an orthogonal projection of each of the first through holes is located within an orthogonal projection of a hole wall of the second hole portion in the axial direction.

11. 9. The battery cell of claim 8, wherein the first hole portion is located between the second hole portion and the electrode assembly, a surface of the fastener facing away from the electrode assembly abuts the transition surface, the second through hole further includes a third hole portion, the third hole portion is formed extending from the transition surface along the axial direction to a side facing away from the first hole portion, a radial dimension of the third hole portion is smaller than a radial dimension of the first hole portion and larger than a radial dimension of the second hole portion, and an orthogonal projection of each of the first through holes in the axial direction is located within an orthogonal projection of a hole wall of the third hole portion.

12. 12. The battery cell according to claim 7, wherein the fixing device includes a connection portion and an attachment portion, the connection portion protruding from an outer wall of the attachment portion and being connected to the connection portion, the connection portion being used for connecting to the main body portion, and the attachment portion being used for connecting to the ventilation part.

13. 13. The battery cell according to claim 12, wherein the connection portion is welded to the main body portion, the mounting portion is installed along the thickness direction so as to protrude from the connection portion toward a side on which the electrode assembly is located, and the ventilation part is connected to an end surface of the mounting portion facing the electrode assembly.

14. The battery cell according to claim 12 or 13, wherein a gap is formed between an outer wall of the mounting portion and a hole wall of the second through hole such that the ventilation part and the hole wall of the second through hole are spaced apart.

15. 15. The battery cell according to claim 2, wherein a support for supporting the ventilation part is provided within the accommodation cavity, and the gas can be discharged from the first through hole through the support.

16. The battery cell of claim 15 , wherein the support and the surrounding wall that defines the containment cavity are connected by a chemical bond.

17. The battery cell according to claim 1 , wherein the ventilation part and the end surface of the protrusion are connected by a chemical bond.

18. 18. The battery cell of claim 1 , wherein the outer casing includes a housing and a cover assembly, the housing having an opening, the cover assembly being installed to seal the opening, and one of the housing and the cover assembly includes the wall portion.

19. 19. The battery cell of claim 18, wherein the cover assembly includes the wall portion, and the battery cell further includes an insulating material for separating the cover assembly and the electrode assembly, and a third through hole is provided in the insulating material for communicating with the recess.

20. 20. The battery cell according to claim 19, wherein the number of the third through holes is a plurality, and the plurality of third through holes are spaced apart from each other.

21. A cover assembly for use with a battery cell including an electrode assembly, comprising: a cover plate, a wall portion of the cover plate including a main body portion and a fixture, the fixture being provided with a recess communicating with the outside, the recess being recessed from an inner surface of the fixture facing the electrode assembly in a direction away from the electrode assembly; a ventilation part that is provided between the electrode assembly and the fixing device, covers the recess from the electrode assembly side, and exhausts the gas to the outside of the battery cell through the recess when a gas pressure inside the battery cell reaches a threshold value; Including, a bottom wall of the recess is provided with a protrusion extending toward the electrode assembly, the protrusion being attached to the ventilation part so as to limit deformation of the ventilation part along a thickness direction of the wall part; Cover assembly.

22. A battery comprising a battery cell according to any one of claims 1 to 20.

23. 23. A power consuming device comprising the battery of claim 22, said battery being adapted to provide electrical energy.

24. A method for manufacturing a battery cell, comprising: providing a housing having an opening; providing an electrode assembly and enclosing said electrode assembly within said housing; a cover assembly is provided, and the cover assembly is placed over an opening to form a battery cell, the cover assembly including a cover plate and a ventilation part, a wall portion of the cover plate includes a main body and a fixture, the fixture is provided with a recess communicating with the outside, the recess is recessed from an inner surface of the fixture facing the electrode assembly in a direction away from the electrode assembly, the ventilation part is provided between the electrode assembly and the fixture and covers the recess from the electrode assembly side, the ventilation part is used to exhaust the gas to the outside of the battery cell through the recess when a gas pressure inside the battery cell reaches a threshold value, a protrusion is provided on a bottom wall of the recess extending toward the electrode assembly, and the protrusion is attached to the ventilation part so as to limit deformation of the ventilation part along a thickness direction of the wall portion; Including, How battery cells are manufactured.

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