Battery cell, manufacturing method therefor, battery, and electrical apparatus

Abstract

Provided in the embodiments of the present application are a battery cell, a manufacturing method therefor, a battery and an electrical apparatus. The battery cell comprises a casing (1) provided with a first opening (12); a first end cover (2) sealing the first opening (12) and insulated from the casing (1); and an electrode assembly (3) arranged in the housing (1). The electrode assembly (3) comprises an electrode main body (31), a first tab (32) and a second tab (33), the first tab (32) and the second tab (33) being led out from the electrode main body (31) and having opposite polarities, the first tab (32) being electrically connected to the first end cover (2), and the second tab (33) being electrically connected to the casing (1). The first end cover (2) serves as a first output electrode, and the casing (1) serves as a second output electrode.

Description

Battery cell and manufacturing method thereof, battery and electric device

[0001] Cross-references to related applications

[0002] This disclosure is based on the Chinese application with application number 202311507449.2 and application date November 13, 2023, and claims its priority. The disclosed content of the above-mentioned Chinese application is hereby introduced into this disclosure as a whole. Technical Field

[0003] The present application relates to the field of battery technology, and in particular to a battery cell and a manufacturing method thereof, a battery, and an electrical device. Background Art

[0004] In recent years, new energy vehicles have experienced rapid development. In the electric vehicle sector, power batteries, as the power source of electric vehicles, play an irreplaceable role. With the vigorous promotion of new energy vehicles, the demand for power battery products is also growing. As a core component of new energy vehicles, batteries have high requirements for reliability.

[0005] However, how to improve the energy density of batteries has always been a difficult problem in the industry.

[0006] Summary of the Invention

[0007] The purpose of this application is to increase the energy density of the battery.

[0008] According to a first aspect of the present application, a battery cell is provided, comprising:

[0009] a housing having a first opening;

[0010] a first end cover, closing the first opening and insulated from the housing; and

[0011] An electrode assembly is disposed in the housing, the electrode assembly comprising an electrode body, a first electrode tab, and a second electrode tab. The first electrode tab and the second electrode tab are led out from the electrode body and have opposite polarities. The first electrode tab is electrically connected to the first end cap, and the second electrode tab is electrically connected to the housing.

[0012] The first end cover serves as the first output pole, and the shell serves as the second output pole.

[0013] The battery cell of this embodiment uses the first end cap as the first output pole and the shell as the second output pole, eliminating the need for electrode terminals. This can reduce the height of the battery cell, improve the energy density of the battery cell, reduce the number of parts, and reduce the process difficulty and production cost. Moreover, the end face and side face of the shell can be used as the location for connecting the busbar, which can improve the flexibility of electrically connecting multiple battery cells.

[0014] In some embodiments, the first electrode tab and the second electrode tab are respectively extended from both ends of the electrode body, the shell includes a side wall and a first end wall, the first end wall is connected to the end of the side wall opposite to the first opening, and the second electrode tab is electrically connected to the first end wall.

[0015] This embodiment extends the first and second tabs from each end of the electrode body, ensuring reliable insulation between the positive and negative tabs. Furthermore, when the end face of the electrode body is small, providing a separate tab at each end can improve the tab's current carrying capacity. Furthermore, the first and second tabs are electrically connected to the first end cap and first end wall, respectively, reducing the difficulty of the electrical connection process and improving electrical connection reliability. This also eliminates the need for a current collector, reducing the number of parts and further improving electrical reliability.

[0016] In some embodiments, the first electrode tab is directly connected to the first end cap; and / or the second electrode tab is directly connected to the first end wall.

[0017] This embodiment can omit the current collector in the battery cell to further reduce the height of the battery cell, thereby improving the energy density. It can also reduce the number of parts, reduce the complexity of the electrical connection structure, improve the reliability of the electrical connection, and simplify the assembly process.

[0018] In some embodiments, the shell is provided with a flange at the first opening, and the flange is used to limit the movement of the first end cover in a direction away from the electrode assembly.

[0019] In this embodiment, the first end cover and the shell serve as the first output pole and the second output pole respectively. The first end cover and the shell need to be directly insulated, so they cannot be fixedly connected by welding. The method of limiting by flanging can achieve the limiting of the first end cover through a simple structure, prevent the electrode assembly from moving in the shell, and also facilitate the insulation between the shell and the first end cover.

[0020] In some embodiments, the flange serves as a second output pole.

[0021] This embodiment uses the first end cap as the first output pole and the flange as the second output pole. Both the first output pole and the second output pole can be connected to the busbar. The two output poles are located at the same end of the battery cell. When multiple battery cells are electrically connected and assembled into a battery, there is no need to flip the battery cells when welding the positive and negative busbars. It can be completed by setting different welding parameters and welding in sequence. This can facilitate the installation and connection of the busbar and improve assembly efficiency.

[0022] In some embodiments, the shell includes a side wall and a first end wall, the first end wall is connected to an end of the side wall away from the first opening, and a pressure relief component is provided on the first end wall, which is used to relieve pressure when the pressure in the battery cell exceeds a preset threshold.

[0023] This embodiment places the pressure relief component at the other end of the battery cell, which can reduce the impact of high-temperature exhaust on the side of the manifold during thermal runaway pressure relief, prevent large-scale short circuits or high-voltage sparks in the battery, and avoid causing thermal runaway of the entire power battery system, or even fire and explosion, thereby improving the safety of the power battery system. Secondly, placing the pressure relief component and the output pole at both ends of the housing provides more space for the pressure relief component, which can improve the output pole's current capacity. It also allows for convenient processing of the pressure relief component and more accurate control of its opening pressure. It also prevents welding stress from affecting the opening pressure of the pressure relief component when welding the manifold.

[0024] In some embodiments, the battery cell further includes an insulating component disposed between the first end cover and the shell to achieve insulation between the first end cover and the shell.

[0025] In this embodiment, an insulating component is provided between the first end cap and the housing. This not only provides insulation between the first end cap and the housing, allowing the first end cap and the housing to serve as two output poles, but also ensures reliable insulation between the two output poles. Furthermore, the insulating component also acts as a seal, preventing external impurities and moisture from entering the housing, thereby improving the reliability of the battery cell operation.

[0026] In some embodiments, the insulating member is at least partially disposed between the flange and the first end cap and extends beyond an inner edge of the flange.

[0027] This embodiment can increase the creepage distance between the flange and the first end cover. The creepage distance is the shortest distance between the flange and the first end cover along the surface of the insulating material (i.e., the insulating component). When an abnormal situation occurs in the electrode assembly and high-voltage discharge occurs, it is equivalent to increasing the safety distance inside the battery cell, which can reduce the possibility of risks such as fire and explosion in the electrode assembly and improve the safety of the battery cell operation.

[0028] In some embodiments, the shell includes a side wall, the insulating component includes a first insulating member, the first insulating member includes a first section and a second section, the first section is located between the flange and the first end cover, the second section is connected to the first section, and the second section is located between the outer edge of the first end cover and the side wall.

[0029] The insulating component of this embodiment includes at least an L-shaped structure, which can simultaneously surround the side wall of the first end cover and the area on the outer surface that is in contact with the flange, thereby further improving the reliability of the insulation between the first end cover and the shell.

[0030] In some embodiments, the first insulating member includes a third section, the third section is connected to an end of the second section away from the first section, and the third section is attached to a surface of the first end cap close to the first tab.

[0031] The insulating component of this embodiment forms a C-shaped structure, which can simultaneously surround the side wall of the first end cover, the area on the outer surface that fits with the flange, and the area on the inner surface of the first end cover close to the shell, thereby maximizing the reliability of the insulation between the first end cover and the shell.

[0032] In some embodiments, the housing includes a side wall, the flange includes a first portion and a second portion, the first portion is connected to the side wall, the second portion is connected to the first portion and located radially inward of the first portion, and the second portion serves as a second output pole.

[0033] This embodiment, by disposing the second portion radially inwardly of the first portion, can enhance the position-limiting effect on the first end cap, preventing the first end cap from shifting, and providing a specific location for connecting the busbar, making it easier to position the busbar. This structure positions the first and second output poles at the same end of the battery cell, facilitating the placement of a pressure relief component at the other end. This reduces the impact of high-temperature exhaust on the busbar during thermal runaway pressure relief, prevents large-scale short circuits or high-voltage sparks in the battery, and avoids thermal runaway of the entire power battery system, which could even lead to fire and explosion, thereby improving the safety of the power battery system.

[0034] In some embodiments, the second portion includes a plurality of protrusions, and the plurality of protrusions are spaced apart along the circumference of the housing.

[0035] This embodiment, by providing a protruding portion, increases the contact area between the current busbar and the flange, improving welding reliability and reducing the difficulty of positioning during welding. It also improves the current flow capacity between the flange and the current busbar and enhances electrical conductivity. Furthermore, by providing multiple protruding portions, the current busbar can be selectively connected to the outer surface of any protruding portion, increasing the flexibility of the current busbar's placement.

[0036] In some embodiments, the second portion includes a protrusion that continuously extends over a portion of the circumference of the housing.

[0037] This embodiment, by providing a protrusion, increases the contact area between the busbar and the flange, improving welding reliability and reducing the difficulty of positioning during welding. It also improves the current flow capacity between the flange and the busbar and enhances electrical conductivity. Furthermore, by providing a single, continuously extending protrusion, it facilitates processing and also defines the connection area of ​​the busbar on the flange.

[0038] In some embodiments, the first end cap and the first tab are welded, and the welding tracks are distributed in an area surrounded by an inner edge of the second portion, a side edge of the second portion, and an inner edge of the first portion.

[0039] In this embodiment, when welding the first end cover to the first pole tab, the radial welding size range can be increased to increase the distribution range of the first pole tab that allows current to pass directly. During the charging and discharging process, lithium ions can be more smoothly deintercalated and intercalated, reducing the risk of lithium plating and improving the conductivity between the first end cover and the first pole tab.

[0040] In some embodiments, the battery cell further includes an insulating component disposed between the first end cover and the housing to achieve insulation between the first end cover and the housing. The insulating component includes:

[0041] a first insulating member; and

[0042] The second insulating member is arranged radially inward of the first insulating member, and the heat-resistant temperature of the second insulating member is higher than the heat-resistant temperature of the first insulating member.

[0043] In this embodiment, the busbar is welded to the second portion, which can prevent insulation failure caused by heat generated by high temperature during the welding process, thereby improving the reliability of the battery cell.

[0044] In some embodiments, the docking position between the second insulating member and the first insulating member adopts a concave-convex structure.

[0045] This embodiment adopts a concave-convex structure at the docking position of the second insulating member and the first insulating member, which can make the second insulating member and the first insulating member tightly fit together, prevent the formation of a gap between the two and cause a short circuit between the flange and the first end cover, and also improve the sealing effect.

[0046] In some embodiments, the Vickers hardness of the first insulating member is lower than the Vickers hardness of the second insulating member, and the thickness of the first insulating member between the first portion and the first end cap is greater than the maximum thickness of the second insulating member.

[0047] This embodiment takes into account the difficulty of achieving both sealing and high-temperature insulation with current insulating materials. The first insulating member is designed to have a lower Vickers hardness and a greater thickness. When the first and second insulating members are simultaneously squeezed between the flange and the first end cap, the first insulating member undergoes a significant deformation to achieve flush surfaces, resulting in a superior sealing effect. Furthermore, the second insulating member also provides high-temperature insulation. When welding the busbar to the second portion, this prevents insulation failure caused by the high temperature generated during welding, thereby improving the reliability of the battery cell.

[0048] In some embodiments, the flange is configured to be formed by removing material at the first opening.

[0049] This embodiment facilitates the formation of flanges of any shape and is also conducive to forming wider flanges, which can increase the welding contact area between the manifold and the flange, improve welding reliability, reduce the difficulty of positioning during welding, and improve the flow capacity between the flange and the manifold. Moreover, the first opening can be flexibly punched into the required shape to further meet the layout requirements of the welding track between the first end cover and the first tab. In addition, compared with the rolling method, the flange formed by removing material can ensure the flatness of the flange, which is not affected by the shape of the battery cell and the width of the flange, and will not cause wrinkles on the flange. No flattening treatment is required, and the flange can also be reliably contacted with the insulating component to improve the sealing effect.

[0050] In some embodiments, the shell includes a side wall and a first end wall, the first end wall is connected to an end of the side wall opposite to the first opening, the side wall has a second opening, the first end wall is formed by a second end cover, and the second end cover is used to close the second opening.

[0051] This embodiment is based on a structure in which a flange is formed by removing material. As shown in the figure and the figure, the closed end of the container needs to be punched to form a first opening. The container includes a side wall and a second end wall. The second end wall is connected to one end of the side wall. The second end wall can completely close the opening of the side wall, or partially close the opening of the side wall, but it is necessary to ensure that the second end wall completely covers the flange, and the covering area is larger than the area of ​​the flange. Since a second end wall is provided at one end of the side wall, a second opening needs to be provided at the other end, and the second opening is closed by a separate second end cover. This structure provides conditions for forming a flange by removing material.

[0052] In some embodiments, the second end cap is connected to the side wall by a first weld formed between an outer edge of the second end cap and an inner surface of the side wall.

[0053] This embodiment can simplify the structure of the second end cover, and the second end cover does not need to protrude from the end of the side wall, which can further reduce the height of the battery cell, thereby improving the energy density of the battery cell.

[0054] In some embodiments, the second end cover is connected to the side wall by a first weld, the second end cover includes a first main body portion and a bent portion, the first end of the bent portion is connected to the outer edge of the first main body portion, the second end of the bent portion is covered with the end of the side wall, and the first weld is formed between the second end of the bent portion and the end of the side wall.

[0055] The second end cap of this embodiment is provided with a bent portion, and the second end of the bent portion and the end covering the side wall can be used to position the second end cap along the height direction of the battery cell, preventing the second end cap from moving during welding without the need for additional tooling. Furthermore, if the pressure relief component is provided on the second end cap, the central area of ​​the second end cap is recessed inward, reducing the risk of damage to the pressure relief component due to external impact.

[0056] In some embodiments, the shell includes a side wall and a first end wall, the first end wall is connected to an end of the side wall opposite to the first opening, the flange only includes a first portion, the first portion is connected to the side wall, and the first end wall serves as the second output pole.

[0057] This embodiment can be used only to limit the electrode assembly when the radial width of the flange is narrow, and the first end wall is used as the second output pole. This provides a larger area for the second output pole to connect to the busbar, which is also beneficial for positioning during the welding process and can improve the reliability of the electrical connection.

[0058] In some embodiments, the flange is configured to be formed by bending an end portion of the side wall.

[0059] This embodiment forms a flange by bending, and a shell with a side wall and a first end wall integrally formed can be used. After the electrode assembly is installed in the shell, it is directly bent into a flange without the need for an additional process to form an opening, which can simplify the process flow and improve assembly efficiency.

[0060] In some embodiments, the side wall and the first end wall are integrally formed.

[0061] In this embodiment, the side wall and the first end wall are formed integrally, which can save the additional process of connecting the first end wall to the side wall, further simplify the process flow, and improve assembly efficiency.

[0062] In some embodiments, the shell includes a side wall, the side wall includes a second body portion and a protrusion, the protrusion protrudes toward the inside of the shell relative to the second body portion, and the protrusion is located between the first end cover and the electrode body in the height direction of the battery cell.

[0063] This embodiment provides support for the edge position of the first end cover by arranging a protrusion on the side wall, so that the protrusion can support the first end cover together with the first pole tab. When the first end cover is subjected to external compression or the battery cell is subjected to vibration force, the force on the first pole tab can be reduced, the first pole tab can be prevented from deformation, and the reliability of the electrical connection between the first end cover and the first pole tab can be improved.

[0064] In some embodiments, the protrusion extends to the radial inside of the outer sidewall of the electrode body.

[0065] This embodiment allows the protrusion to extend to the radial inner side of the outer side wall of the electrode body, so that the protrusion can be supported between the electrode body and the first end cover to provide more stable support for the first end cover, and can maintain the height of the first electrode tab, thereby improving the reliability of the electrical connection between the first electrode tab and the first end cover.

[0066] In some embodiments, the outer edge of the first electrode tab is retracted inwardly by a preset distance from the outer sidewall of the electrode body.

[0067] In this embodiment, the outer edge of the first pole lug is retracted inward by a preset distance, which can allow the protrusion to be designed with a larger extension length in the radial direction, so as to provide more stable support for the first end cover and maintain the height of the first pole lug; it can also avoid excessive squeezing of the insulating material on the side wall of the first pole lug when the protrusion is formed during the assembly process, causing insulation failure; in addition, when the insulating component wraps the edge area of ​​the inner surface of the first end cover, the first pole lug can also avoid the insulating component.

[0068] In some embodiments, the battery cell also includes a third insulating member, the third insulating member includes a fourth segment and a fifth segment, the fourth segment is adhered to the outer wall of the first pole ear, the first end of the fifth segment is connected to an end of the fourth segment close to the root of the first pole ear, and the fifth segment is adhered to the area of ​​the end surface of the electrode body where the first pole ear is not provided.

[0069] This embodiment can cover the outer side wall of the first tab and the area of ​​the end face of the electrode body where the first tab is not provided by the third insulating member, thereby preventing short circuit caused by contact with the protrusion and improving the insulation reliability between the electrode assembly and the shell.

[0070] In some embodiments, the third insulating member further includes a sixth segment, the sixth segment covers an end region of an outer sidewall of the electrode body, and a first end of the sixth segment is connected to a second end of the fifth segment.

[0071] This embodiment can cover the end area of ​​the outer side wall of the electrode body by providing the sixth section, thereby improving the insulation reliability between the electrode body and the side wall and preventing short circuit.

[0072] In some embodiments, the third insulating member further includes a seventh segment, the seventh segment is attached to the end surface of the first tab near the outer edge, and a first end of the seventh segment is connected to an end of the fourth segment away from the root of the first tab.

[0073] This embodiment can cover the outer edge area of ​​the first pole lug by providing the seventh section, and together with the fourth section, fully cover the first pole lug to improve the insulation performance, and can also smooth and fit the outer edge area of ​​the first pole lug, so that the first end cover and the end face of the first pole lug can better fit.

[0074] In some embodiments, the material of the shell includes steel, the material of the first end cover includes aluminum, the first end cover serves as the positive output pole, and the shell serves as the negative output pole; or the material of the shell includes aluminum, the material of the first end cover includes copper or steel, the first end cover serves as the negative output pole, and the shell serves as the positive output pole.

[0075] In this embodiment, the polarities of the first output electrode and the second output electrode can be selected according to the material of the first end cover, so as to achieve matching material welding as much as possible and reduce the risk of leakage after welding.

[0076] In some embodiments, the battery cells are cylindrical in shape.

[0077] For cylindrical battery cells, it is convenient to form the first opening by removing material. Moreover, if the flange is formed by bending the end of the side wall, wrinkles are not easily generated when rolling the flange.

[0078] According to a second aspect of the present application, a battery is provided, comprising the battery cell of the above embodiment.

[0079] According to a third aspect of the present application, an electrical device is provided, comprising the battery cell or battery of the above embodiment.

[0080] According to a fourth aspect of the present application, a method for manufacturing a battery cell is provided, comprising:

[0081] Providing an assembly step: providing a housing, a first end cap, and an electrode assembly, wherein the housing has a first opening, and the electrode assembly includes an electrode body, a first electrode tab, and a second electrode tab, wherein the first electrode tab and the second electrode tab are led out from the electrode body and have opposite polarities;

[0082] Electrode placement steps: Place the electrode assembly into the housing;

[0083] A first sealing step: closing the first opening with a first end cover and insulating the first end cover from the housing;

[0084] Electrical connection step: electrically connecting the first electrode tab to the first end cover, and electrically connecting the second electrode tab to the shell, the first end cover serving as the first output pole, and the shell serving as the second output pole.

[0085] The battery cell of this embodiment uses the first end cap as the first output pole and the shell as the second output pole, eliminating the need for electrode terminals. This can reduce the height of the battery cell, improve the energy density of the battery cell, reduce the number of parts, and reduce the process difficulty and production cost. Moreover, the end face and side face of the shell can be used as the location for connecting the busbar, which can improve the flexibility when electrically connecting multiple battery cells.

[0086] In some embodiments, the manufacturing method further comprises:

[0087] providing a container having a side wall and a second end wall connected to an end of the side wall;

[0088] A first opening is formed by removing material from the second end wall, and a flange is formed on the outer side of the first opening. The flange is used to limit the movement of the first end cover in a direction away from the electrode assembly.

[0089] This embodiment facilitates the formation of flanges of any shape and is also conducive to forming wider flanges, which can increase the welding contact area between the manifold and the flange, improve welding reliability, reduce the difficulty of positioning during welding, and improve the flow capacity between the flange and the manifold. Moreover, the first opening can be flexibly punched into the required shape to further meet the layout requirements of the welding track between the first end cover and the first tab. In addition, compared with the rolling method, the flange formed by removing material can ensure the flatness of the flange, which is not affected by the shape of the battery cell and the width of the flange, and will not cause wrinkles on the flange. No flattening treatment is required, and the flange can also be reliably contacted with the insulating component to improve the sealing effect.

[0090] In some embodiments, the container has a second opening, the second opening is opposite to the second end wall, and the first sealing step includes:

[0091] Before the step of placing the electrode, the first end cap is placed into the receiving member through the second opening so that the first end cap closes the first opening.

[0092] In this embodiment, for a structure in which a flange is formed by removing material, the first end cap can be placed in the second opening at the other end of the container to close the first opening, and then the electrode assembly can be placed in, thereby achieving smooth installation of the first end cap.

[0093] In some embodiments, the battery cell further includes an insulating component disposed between the first end cap and the housing for achieving insulation between the first end cap and the housing. The first sealing step further includes:

[0094] The insulating component is placed in the receiving member having the first opening.

[0095] In this embodiment, for the structure in which the flange is formed by removing material, the second opening at the other end of the receiving member can be used to place the insulating component, so as to achieve insulation from the shell after the first end cover is placed.

[0096] In some embodiments, after the insulating component and the first end cover are placed, the side wall of the container is rolled to form a protrusion, which protrudes toward the inside of the shell and is used to limit the first end cover.

[0097] This embodiment, after the raised portion is formed by rolling, can limit the position of the first end cap and the insulating component, preventing the first end cap from shifting, and ensuring good positioning after the electrode assembly is installed. If the insulating component's lateral extension exceeds the inner surface of the first end cap, the excess portion of the insulating component can be bent during rolling until it aligns with the inner surface of the first end cap, thereby achieving insulation between the raised portion and the first end cap.

[0098] In some embodiments, the manufacturing method further includes a second sealing step, the second sealing step including:

[0099] After the first sealing step and the electrode placement step, the second opening is closed by a second end cap.

[0100] After the electrode assembly is placed in this embodiment, the second opening is sealed with a second end cap, allowing installation of all components. The second end cap can be welded to the side wall. Sealing the second opening with a separate second end cap allows for the formation of a flange by removing material.

[0101] In some embodiments, the housing includes a side wall and a first end wall, the first end wall being connected to an end of the side wall opposite the first opening, and the first sealing step includes:

[0102] After the electrode placement step, the first end cap is covered on the first electrode tab, and the end of the side wall is bent to form a flange, which is used to limit the movement of the first end cap away from the electrode assembly so that the first end cap closes the first opening.

[0103] This embodiment forms a flange by bending, and a shell with a side wall and a first end wall integrally formed can be used. After the electrode assembly is installed in the shell, it is directly bent into a flange without the need for an additional process to form an opening, which can simplify the process flow and improve assembly efficiency.

[0104] In some embodiments, the step of bending the end of the side wall to form a flange includes:

[0105] The end of the side wall is bent to form a flange by upsetting.

[0106] This embodiment forms the flange by upsetting, which has a simple process and can select suitable insulating components according to the shape of the flange to achieve comprehensive improvement in insulation performance, sealing performance and creepage distance.

[0107] In some embodiments, the step of bending the end of the side wall to form a flange includes:

[0108] Insulating glue is provided on the inner surface of the side wall at the first opening;

[0109] The end of the side wall is hot-pressed to form a flange, the flange and the first end cover are bonded by insulating glue, and the insulating glue is solidified to form an insulating component, which is used to achieve insulation between the first end cover and the shell.

[0110] This embodiment can achieve greater connection strength by adopting thermal composite sealing, and can eliminate the need to form a raised portion by roller grooves. Not providing a raised portion is beneficial for reducing the height of the first pole ear, thereby reducing the overall height of the battery cell, thereby improving the energy density of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0111] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the drawings without creative work.

[0112] FIG1 is a schematic structural diagram of some embodiments of the present application for installing a battery on a vehicle.

[0113] FIG2 is an exploded view of the first embodiment of the battery of the present application.

[0114] FIG3 is an external view of a first embodiment of a battery cell of the present application.

[0115] FIG4 is a cross-sectional view of a first embodiment of a battery cell of the present application.

[0116] FIG. 5A is a schematic structural diagram of some embodiments of the flange in FIG. 4 .

[0117] FIG. 5B is a schematic diagram of a modified embodiment of FIG. 5A .

[0118] FIG6 is an enlarged view of point A in FIG4 .

[0119] FIG7A is an enlarged view of point B in FIG4 .

[0120] FIG. 7B is a schematic diagram of a modified embodiment of FIG. 7A .

[0121] FIG8 is a schematic structural diagram of a container provided during the assembly process of the first embodiment of the battery cell of the present application.

[0122] FIG9 is a schematic structural diagram of removing material from the second end wall of the container to form a first opening.

[0123] FIG. 10 is a schematic diagram showing the insulating component and the first end cap being placed in the receiving member forming the first opening.

[0124] Figure 11 is a bottom view of Figure 10.

[0125] FIG. 12 is a schematic structural diagram of a protrusion formed on a side wall of a container.

[0126] FIG13 is a cross-sectional view of a second embodiment of a battery cell of the present application.

[0127] FIG14 is a cross-sectional view of a third embodiment of a battery cell of the present application.

[0128] In the drawings, the drawings are not drawn to scale.

[0129] Marking instructions: 100, battery cell; 1, shell; 1', container; 11, flange; 111, first part; 112, second part; 112', protrusion; 12, first opening; 13, side wall; 131, second main body; 132, protrusion; 14, first end wall; 15, second opening; 16, second end wall; 2, first end cover; 21, liquid injection hole; 22, second weld; 23, fourth weld; 3, electrode assembly; 31, electrode body; 311, through hole; 32, first pole ear; 33, second pole ear; 4, second end cover; 41, first weld; 42, third weld; 43, first main body; 44, bending part; 5', insulating component; 5, first insulating member; 50, concave-convex structure; 51, first section; 52, second section; 53, Third section; 5A, first protrusion; 6, second insulating member; 6A, second protrusion; 7, sealing member; 8, pressure relief member; 81, notch; 9, third insulating member; 91, fourth section; 92, fifth section; 93, sixth section; 94, seventh section; 200, battery; 201, case assembly; 201A, case; 201B, first cover; 201C, second cover; 300, vehicle; 301, axle; 302, wheel; 303, motor; 304, controller. DETAILED DESCRIPTION

[0130] The following detailed description of the embodiments of the present application is provided in conjunction with the accompanying drawings and examples. The following detailed description of the embodiments and the accompanying drawings are used to illustrate the principles of the present application, but are not intended to limit the scope of the present application, i.e., the present application is not limited to the described embodiments.

[0131] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0132] This application uses descriptions of directions or positional relationships such as "up", "down", "top", "bottom", "front", "back", "inside" and "outside" to facilitate the description of this application, and does not indicate or imply that the device referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, it should not be understood as limiting the scope of protection of this application.

[0133] Furthermore, the terms "first," "second," and "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. "Perpendicular" does not strictly refer to perpendicularity, but rather to the tolerances allowed. "Parallel" does not strictly refer to parallelism, but rather to the tolerances allowed. The directional terms used in the following description refer to the directions shown in the figures and are not intended to limit the specific structure of this application.

[0134] It should also be noted that, in the description of this application, unless otherwise specified or limited, the terms "installed," "connected," and "connected" should be understood broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to direct connections or indirect connections through an intermediary. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0135] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least some embodiments of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0136] Current battery cells usually include a shell and an electrode assembly housed in the shell, and the shell is filled with an electrolyte. The electrode assembly is mainly formed by stacking or winding a first electrode sheet and a second electrode sheet with opposite polarities, and an insulating member, such as a diaphragm, is usually provided between the first electrode sheet and the second electrode sheet. The portions of the first electrode sheet and the second electrode sheet coated with active material constitute the main body of the electrode assembly, and the portions of the first electrode sheet and the second electrode sheet not coated with active material each constitute the first electrode tab and the second electrode tab. In a battery cell, the first electrode sheet can be a positive electrode sheet, including a positive electrode current collector and a positive electrode active material layer provided on both sides of the positive electrode current collector. The positive electrode current collector can be a metal foil or a composite current collector. For example, as the metal foil, aluminum or stainless steel with a silver surface treatment, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc. can be used. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate made of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.). The positive electrode active material layer may include at least one of the following materials: lithium-containing phosphate, lithium transition metal oxide, and their respective modified compounds. However, the present application is not limited to these materials, and other traditional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials may be used alone or in combination of two or more. The second electrode sheet may be a negative electrode sheet, including a negative electrode current collector and a negative electrode active material layer provided on both sides of the negative electrode current collector. The negative electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, aluminum or stainless steel with a silver surface treatment, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc. may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.). The negative electrode active material layer can adopt the negative electrode active material for batteries known in the art. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based material, tin-based material and lithium titanate, etc. Optionally, the first pole piece can also be a negative pole piece, and the corresponding second pole piece is a positive pole piece. The first pole piece and the second pole piece can be located together at one end of the main body or respectively at both ends of the main body. During the charge and discharge process of the battery cell, the positive electrode active material and the negative electrode active material react with the electrolyte, and the pole pieces connect the electrode terminals to form a current loop.

[0137] In current battery cell structures, the positive output electrode is typically connected via an electrode terminal located on the end cap. This electrode terminal protrudes a certain height from the outer surface of the end cap, increasing the overall height of the battery cell and thus reducing its energy density. Based on the shortcomings of this structure, this application aims to reduce the height of the battery cell by reducing the space occupied by the electrode terminal.

[0138] In accordance with the above-mentioned solution, the present application proposes a battery cell, comprising: a shell having a first opening; a first end cover, closing the first opening and insulated from the shell; and an electrode assembly, arranged in the shell, the electrode assembly comprising an electrode body, a first pole tab and a second pole tab, the first pole tab and the second pole tab being led out from the electrode body and having opposite polarities, the first pole tab being electrically connected to the first end cover, and the second pole tab being electrically connected to the shell; wherein the first end cover serves as a first output pole, and the shell serves as a second output pole.

[0139] The battery cell of this embodiment uses the first end cap as the first output pole and the shell as the second output pole, eliminating the need for electrode terminals. This can reduce the height of the battery cell and improve its energy density. It can also reduce the number of parts, lower process difficulty and production costs.

[0140] The battery cells of the embodiments of the present application are applicable to batteries and electrical devices using such battery cells, and the batteries are also applicable to electrical devices.

[0141] The battery of the embodiment of the present application can be used in an electrical device, which can be a battery car, an electric car, a ship, or a spacecraft, for example, a spacecraft includes an airplane, a rocket, a space shuttle, and a spacecraft.

[0142] As shown in Figure 1 , the power-consuming device can be a vehicle 300, such as a new energy vehicle, which can be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle; or the power-consuming device can be a drone or a ship. Specifically, vehicle 300 may include an axle 301, wheels 302 connected to axle 301, a motor 303, a controller 304, and a battery 200. Motor 303 is used to drive axle 301, and controller 304 is used to control the operation of motor 303. Battery 200 can be located at the bottom, front, or rear of vehicle 300 to provide power to motor 303 and other components of the vehicle.

[0143] As shown in Figure 2, the battery 200 includes a housing assembly 201 and battery cells 100. In the battery 200, there can be one or more battery cells 100. If there are multiple battery cells 100, the multiple battery cells 100 can be connected in series, in parallel, or in a hybrid connection. Hybrid connection means that the multiple battery cells 100 are connected in both series and parallel. Multiple battery cells 100 can be connected in series, in parallel, or in a hybrid connection to form a battery module, and the multiple battery modules can then be connected in series, in parallel, or in a hybrid connection to form a whole and accommodated in the housing assembly 201. Alternatively, all battery cells 100 can be directly connected in series, in parallel, or in a hybrid connection, and then the whole formed by all battery cells 100 is accommodated in the housing assembly 201.

[0144] Among them, the box assembly 201 can be a part of the battery pack, and the box assembly 201 can be detachably installed on the electrical device; or, the box assembly 201 can also be a space formed by a structural member in the electrical device for accommodating the battery cell 100. For example, when the battery cell 100 is used in the vehicle 300, the box assembly 201 is a space formed by the vehicle frame for accommodating the battery cell 100.

[0145] The housing assembly 201 is hollow and is used to accommodate one or more battery cells 100. Depending on the shape, quantity, and combination of the battery cells 100 to be accommodated, as well as other requirements, the housing assembly 201 can have different shapes and sizes. For example, the housing assembly 201 may include: a housing 201A, a first cover 201B, and a second cover 201C. The housing 201A has openings at both ends, and the first and second covers 201B and 201C are used to seal the openings at both ends of the housing 201A. In Figure 2, the housing 201A has a rectangular cylindrical structure based on the arrangement of the multiple battery cells 100. To facilitate maintenance of the batteries 200, the housing assembly 201 can be removably mounted to the electrical device.

[0146] The battery cell 100 may be a secondary battery. A secondary battery refers to a battery cell 100 that can be continuously used by activating active materials by charging after the battery cell 100 is discharged.

[0147] The battery cell 100 can be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel metal hydride battery, a nickel cadmium battery, a lead storage battery, etc., which is not limited in the embodiments of the present application.

[0148] As an example, the battery cell 100 can be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell or a battery cell of other shapes. The prismatic battery cell includes a square-shell battery cell, a blade-shaped battery cell, a polygonal battery, and a polygonal battery such as a hexagonal battery. There is no special limitation in this application.

[0149] The following description uses cylindrical battery cells 100 as an example, but is also applicable to battery cells of other shapes. Multiple battery cells 100 can be arranged in a plurality of planes xoy perpendicular to a first direction z. The multiple battery cells 100 can be arranged in a rectangular array along a second direction x and a third direction y, with the second direction x being perpendicular to the third direction y.

[0150] Figure 3 is an external view of some embodiments of the battery cell of the present application, and Figure 4 is a cross-sectional view of some embodiments of the battery cell of the present application. The battery cell 100 includes: a housing 1 having a first opening 12; a first end cap 2 that seals the first opening 12 and is insulated from the housing 1; and an electrode assembly 3 disposed within the housing 1. The electrode assembly 3 includes an electrode body 31, a first electrode tab 32, and a second electrode tab 33. The first electrode tab 32 and the second electrode tab 33 extend from the electrode body 31 and have opposite polarities. The first electrode tab 32 is electrically connected to the first end cap 2, and the second electrode tab 33 is electrically connected to the housing 1. The first end cap 2 serves as a first output electrode, and the housing 1 serves as a second output electrode.

[0151] The housing 1 has a thin-walled hollow structure for accommodating the electrode assembly 3 and the electrolyte. The housing 1 can be a steel shell, an aluminum shell, a composite metal shell (such as a copper-aluminum composite shell), or an aluminum-plastic film. The housing 1 can be cylindrical, with a first opening 12 provided at one axial end of the housing 1 and covered by a first end cap 2. The other end of the housing 1 is closed, or also has an opening and is closed by an end cap.

[0152] The electrode assembly 3 is formed by winding a first electrode sheet and a second electrode sheet of opposite polarity around a winding axis K. The winding axis K is aligned with the first direction z. A separator, such as a diaphragm, is typically provided between the first and second electrode sheets. For cylindrical battery cells 100, the wound electrode assembly 3 can be cylindrical. Alternatively, the battery cell 100 can be rectangular, and the wound electrode assembly 3 can be flat.

[0153] The portions of the first and second electrode sheets coated with active material constitute the electrode body 31. A first through-hole 311 is provided in the center of the electrode body 31 to accommodate electrolyte or to serve as a vent for pressure relief. The portions of the first and second electrode sheets not coated with active material each constitute a first electrode tab 32 and a second electrode tab 33. One of the first and second electrode tabs 32, 33 is the negative electrode tab, and the other is the positive electrode tab. The first and second electrode tabs 32, 33 can be extended from the same end of the electrode body 31, or from opposite ends of the electrode body 31.

[0154] The first tab 32 is electrically connected to the first end cap 2, and the second tab 33 is electrically connected to the housing 1. Specifically, the tab 33 can be electrically connected to the side wall or end wall of the housing 1, for example, by welding. The first end cap 2 serves as the first output pole, and the housing 1 serves as the second output pole. The first output pole and the second output pole have opposite polarities, for example, the first output pole is positive and the second output pole is negative, or vice versa. In addition, the first end cap 2 and the housing 1 are insulated.

[0155] The battery cell 100 of this embodiment uses the first end cap 2 as the first output pole and the shell 1 as the second output pole, eliminating the need for electrode terminals. This can reduce the height of the battery cell 100, improve the energy density of the battery cell 100, reduce the number of parts, and reduce the process difficulty and production cost. Moreover, the end face and side face of the shell 1 can be used as the location for connecting the busbar, which can improve the flexibility when electrically connecting multiple battery cells 100.

[0156] In some embodiments, as shown in Figure 4, the first pole tab 32 and the second pole tab 33 are respectively led out from both ends of the electrode body 31, and the shell 1 includes a side wall 13 and a first end wall 14, the first end wall 14 is connected to the end of the side wall 13 opposite to the first opening 12, and the second pole tab 33 is electrically connected to the first end wall 14.

[0157] Among them, for a cylindrical battery cell, the side wall 13 can be cylindrical, the first end wall 14 closes the end of the side wall 13 away from the first opening 12, the first pole ear 32 is electrically connected to the first end cover 2, the second pole ear 33 is electrically connected to the first end wall 14, and the first end wall 14 and the first end cover 2 are respectively located at the two ends of the side wall 13, and the electrical connection can be achieved, for example, by welding.

[0158] Alternatively, for a structure in which the first electrode tab 32 and the second electrode tab 33 are respectively led out from both ends of the electrode body 31, the second electrode tab 33 may also be electrically connected to the side wall 13. Alternatively, the first electrode tab 32 and the second electrode tab 33 may also be led out from the same end of the electrode body 31.

[0159] In this embodiment, the first and second tabs 32, 33 are extended from the ends of the electrode body 31, respectively, which helps ensure the insulation reliability between the positive and negative tabs. Furthermore, when the end face dimensions of the electrode body 31 are small, providing a separate tab at each end can improve the tab's current carrying capacity. Furthermore, the first and second tabs 32, 33 are electrically connected to the first end cap 2 and the first end wall 14, respectively, which reduces the difficulty of the electrical connection process and improves the reliability of the electrical connection. It also eliminates the need for a current collector, reduces the number of parts, and further improves the electrical conductivity reliability.

[0160] In some embodiments, the first electrode tab 32 is directly connected to the first end cap 2 ; and / or the second electrode tab 33 is directly connected to the first end wall 14 .

[0161] Specifically, the first tab 32 can be flattened to form a flat end surface, and the first end cap 2 is welded to the entire flattened end surface of the first tab 32. The second tab 33 can be flattened to form a flat end surface, and the first end wall 14 is welded to the entire flattened end surface of the second tab 33.

[0162] Optionally, the first electrode tab 32 is electrically connected to the first end cover 2 via a first current collecting member, and / or the second electrode tab 33 is electrically connected to the first end wall 14 via a second current collecting member.

[0163] This embodiment can omit the current collector in the battery cell 100 to further reduce the height of the battery cell 100, thereby improving energy density, reducing the number of parts, reducing the complexity of the electrical connection structure, improving electrical connection reliability, and simplifying the assembly process.

[0164] In some embodiments, as shown in FIG. 4 , the housing 1 is provided with a flange 11 at the first opening 12 , and the flange 11 is used to limit the movement of the first end cover 2 in a direction away from the electrode assembly 3 .

[0165] The flange 11 is arranged at an angle relative to the side wall 13 of the housing 1, for example, forming a right angle. The flange 11 and the side wall 13 can be integrally formed or connected by welding. The flange 11 can extend continuously along the entire circumference of the housing 1 to improve the overall strength of the flange 11 and optimize the retaining effect; or the flange 11 can be arranged at intervals along the entire circumference of the housing 1.

[0166] In this embodiment, the first end cover 2 and the shell 1 serve as the first output pole and the second output pole respectively. The first end cover 2 and the shell 1 need to be directly insulated, so they cannot be fixedly connected by welding. The method of limiting by the flange 11 can achieve the limitation of the first end cover 2 through a simple structure, prevent the electrode assembly 3 from moving in the shell 1, and also facilitate the insulation between the shell 1 and the first end cover 2.

[0167] In some embodiments, the flange 11 serves as a second output pole.

[0168] Insulation is provided between the flange 11 and the first end cap 2, for example, an insulating member or insulating glue may be provided between the two. When multiple battery cells 100 are electrically connected and assembled into a battery 200, the battery 200 further includes a first busbar and a second busbar. One end of the first busbar is connected to the first end cap 2, and one end of the second busbar is connected to the flange 11. The busbar leading out of the first end cap 2 will pass through the flange 11. In order to achieve insulation between the first busbar and the flange 11, an insulating layer may be provided between the first busbar and the flange 11, such as a fixed insulating pad or insulating film, or an insulating layer may be coated on the outer surface of the first busbar, or an insulating layer may be coated on the outer surface of the flange 11 in the area where the first busbar passes.

[0169] As shown in Figure 4, if the outer surface of the first end cap 2 is lower than the outer surface of the flange 11, then in order to lead out the first manifold, the first manifold can be provided with a bent structure or locally thickened in the area where the first end cap 2 is exposed to accommodate the height difference between the first end cap 2 and the flange 11. Alternatively, if the outer surface of the first end cap 2 is lower than and flush with the outer surface of the flange 11, the first manifold can be designed as a flat plate structure.

[0170] Optionally, the second output pole can also be led out from the end face or side wall 13 of the shell 1 opposite to the first opening 12, thereby improving the flexibility of leading out the second output pole, and is not limited to the first output pole and the second output pole being led out only from the two ends of the battery cell 100.

[0171] In this embodiment, the first end cap 2 serves as the first output pole and the flange 11 serves as the second output pole. Both the first output pole and the second output pole can be connected to the busbar. The two output poles are located at the same end of the battery cell 100. When multiple battery cells 100 are electrically connected and assembled into a battery 200, there is no need to flip the battery cell 100 when welding the positive and negative busbars. It is only necessary to set different welding parameters and weld them in sequence, which can facilitate the installation and connection of the busbar and improve assembly efficiency.

[0172] In some embodiments, the shell 1 includes a side wall 13 and a first end wall 14, the first end wall 14 is connected to the end of the side wall 13 away from the first opening 12, and a pressure relief component 8 is provided on the first end wall 14, and the pressure relief component 8 is used to relieve pressure when the pressure in the battery cell 100 exceeds a preset threshold.

[0173] The pressure relief component 8 can be integrally formed with the first end wall 14, that is, a reduced thickness portion can be provided on the first end wall 14, with the area enclosed by the reduced thickness portion constituting the pressure relief component 8. For example, the reduced thickness portion can be a notch 81, provided on the inner wall of the first end wall 14 to prevent rust at the location of the notch 81 due to high moisture content outside the battery cell 100; and / or the notch 81 can be provided on the outer wall of the first end wall 14. Integrally forming the side wall 13 and the first end wall 14 facilitates the processing of the notch 81. When the pressure relief component 8 is opened, the reduced thickness portion of the pressure relief component 8 is destroyed, thereby forming an opening or channel for the internal pressure or temperature to be released.

[0174] This embodiment places the pressure relief component 8 at the other end of the battery cell 100, which can reduce the impact of high-temperature exhaust on the side of the manifold during thermal runaway pressure relief, prevent large-scale short circuits or high-voltage ignition in the battery 200, and avoid causing thermal runaway of the entire power battery system, or even fire and explosion, thereby improving the safety of the power battery system. Secondly, placing the pressure relief component 8 and the output pole at both ends of the housing 1 provides more space for the pressure relief component 8, which can improve the current flow capacity of the output pole. It also allows for convenient processing of the pressure relief component 8 and more accurate control of its opening pressure. It also prevents welding stress from affecting the opening pressure of the pressure relief component 8 when welding the manifold.

[0175] In some embodiments, the battery cell further includes an insulating component 5 ′, which is disposed between the first end cover 2 and the housing 1 to achieve insulation between the first end cover 2 and the housing 1 .

[0176] The insulating component 5 ′ can be made of insulating material and is disposed in a region near the first opening 12 in the housing 1 .

[0177] In this embodiment, an insulating member 5' is provided between the first end cap 2 and the housing 1. This not only provides insulation between the first end cap 2 and the housing 1, allowing the first end cap 2 and the housing 1 to serve as two output poles, but also ensures reliable insulation between the two output poles. Furthermore, the insulating member 5' also acts as a seal, preventing external impurities and moisture from entering the interior of the housing 1, thereby improving the reliability of the battery cell 100.

[0178] In some embodiments, the insulating component 5 ′ is at least partially disposed between the flange 11 and the first end cover 2 , and extends beyond the inner edge of the flange 11 .

[0179] The insulating component 5 ′ may extend beyond the inner edge of the flange 11 in the entire circumference thereof, or may extend beyond the inner edge of the flange 11 in a partial circumference thereof.

[0180] This embodiment can increase the creepage distance between the flange 11 and the first end cover 2. The creepage distance is the shortest distance between the flange 11 and the first end cover 2 along the surface of the insulating material (i.e., the insulating component 5'). When an abnormal situation occurs in the electrode assembly 3 and high voltage (for example, a voltage above 500V) is discharged, it is equivalent to increasing the safety distance inside the battery cell 100, which can reduce the possibility of risks such as fire and explosion in the electrode assembly 3 and improve the safety of the battery cell 100.

[0181] In some embodiments, as shown in Figures 4 and 6, the shell 1 includes a side wall 13, the insulating component 5' includes a first insulating member 5, the first insulating member 5 includes a first section 51 and a second section 52, the first section 51 is located between the flange 11 and the first end cover 2, the second section 52 is connected to the first section 51, and the second section 52 is located between the outer edge of the first end cover 2 and the side wall 13.

[0182] During the assembly process, depending on the structure of the insulating component 5', the insulating component 5' can be first installed on the first end cover 2 and then installed into the housing 1 together; or the insulating component 5' can be first installed into the housing 1 and then the first end cover 2 can be installed into the housing 1.

[0183] The insulating component 5 ′ of this embodiment includes at least an L-shaped structure, which can simultaneously surround the side wall of the first end cover 2 and the area on the outer surface that fits the flange 11 , thereby further improving the reliability of the insulation between the first end cover 2 and the housing 1 .

[0184] In some embodiments, as shown in FIG. 6 , the first insulating member 5 includes a third section 53 , which is connected to an end of the second section 52 away from the first section 51 , and is attached to a surface of the first end cap 2 near the first tab 32 .

[0185] Among them, the radial extension length of the third section 53 along the first end cover 2 is smaller than the radial extension length of the first section 51 along the first end cover 2, which can minimize the space occupied by the third section 53 in the first pole tab 32, thereby increasing the radial distribution range of the first pole tab 32 and improving the current flow capacity.

[0186] The insulating component 5' of this embodiment forms a C-shaped structure, which can simultaneously surround the side wall of the first end cover 2, the area on the outer surface that is in contact with the flange 11, and the area on the inner surface of the first end cover 2 close to the shell 1, thereby maximizing the reliability of the insulation between the first end cover 2 and the shell 1.

[0187] In some embodiments, as shown in Figures 5A and 5B, the shell 1 includes a side wall 13, the flange 11 includes a first part 111 and a second part 112, the first part 111 is connected to the side wall 13, the second part 112 is connected to the first part 111 and is located radially inside the first part 111, and the second part 112 serves as a second output pole.

[0188] For example, the first part 111 may extend along the entire circumference of the side wall 13, and the second part 112 may extend along the entire circumference of the first part 111. The busbar may be connected to any circumferential position of the second part 112 to flexibly arrange the busbar; or the second part 112 may also extend along part of the circumference of the first part 111. At the position where the second part 112 is not set, the welding track of the first end cover 2 and the first pole ear 32 can be set, which can improve the electrical connection reliability between the first end cover 2 and the first pole ear 32.

[0189] This embodiment, by providing a second portion 112 radially inwardly of the first portion 111, can enhance the position-limiting effect on the first end cap 2, preventing the first end cap 2 from shifting, and providing a specific location for connecting the busbar, making it easier to position the busbar. This structure positions the first and second output poles at the same end of the battery cell 100, facilitating the placement of the pressure relief component 8 at the other end. This can reduce the impact of high-temperature exhaust on the busbar side during thermal runaway pressure relief, prevent large-scale short circuits or high-voltage ignition in the battery 200, and avoid thermal runaway of the entire power battery system, which could even lead to fire and explosion, thereby improving the safety of the power battery system.

[0190] In some embodiments, as shown in FIG. 5A , the second portion 112 includes a plurality of protrusions 112 ′, and the plurality of protrusions 112 ′ are spaced apart along the circumference of the housing 1 .

[0191] In Figure 5A, the first portion 111 is annular, with four protrusions 112' spaced apart circumferentially and arranged evenly. The protrusions 112' can be rectangular or annular, and their shape and size can be designed based on the current collector to be welded. The first opening 12 is formed by the radially inner sidewall of the first portion 111, the radially inner sidewalls of the multiple protrusions 112', and the circumferential sidewalls.

[0192] This embodiment, by providing protrusions 112', increases the contact area between the current busbar and flange 11, improving welding reliability and reducing the difficulty of positioning during welding. It also improves the current flow capacity between flange 11 and the current busbar, enhancing electrical conductivity. Furthermore, by providing multiple protrusions 112', the current busbar can be selectively connected to the outer surface of any protrusion 112', increasing the flexibility of the current busbar's placement.

[0193] In some embodiments, as shown in FIG. 5B , the second portion 112 includes a protrusion 112 ′ that continuously extends along a portion of the circumference of the housing 1 .

[0194] In FIG5B , the first portion 111 is annular, with protrusions 112' spaced apart circumferentially. The protrusions 112' can be rectangular or annular. The first opening 12 is formed by the radially inner sidewall of the first portion 111, the radially inner sidewall of the protrusion 112', and the two circumferential sidewalls of the protrusion 112'.

[0195] This embodiment, by providing protrusion 112', increases the contact area between the busbar and flange 11, improving welding reliability and reducing the difficulty of positioning during welding. It also improves the current flow capacity between flange 11 and the busbar and enhances electrical conductivity. Furthermore, by providing a single, continuously extending protrusion 112', processing is facilitated and the connection area of ​​the busbar on flange 11 is also defined.

[0196] In some embodiments, the first end cap 2 and the first tab 32 are welded, and the welding tracks are distributed in the area surrounded by the inner edge of the second portion 112 , the side edge of the second portion 112 and the inner edge of the first portion 111 .

[0197] As shown in FIG5A , adjacent protrusions 112 ′ form blank areas, where welding tracks between the first end cap 2 and the first tab 32 can be set. For example, multiple radial welding tracks can be set along the circumference to improve the electrical connection reliability between the first end cap 2 and the first tab 32 .

[0198] As shown in FIG5B , a blank area is formed between the two circumferential side walls of the protrusion 112′, both of which can be used to set welding tracks between the first end cap 2 and the first electrode tab 32, thereby improving the reliability of the electrical connection between the first end cap 2 and the first electrode tab 32. For example, the central angle of the protrusion 112′ is less than 180°, thereby allowing for the setting of more welding tracks. In addition, the central angle of the protrusion 112′ can also be set to other angles.

[0199] In this embodiment, when welding the first end cover 2 to the first pole tab 32, the radial welding size range can be increased to increase the distribution range of the first pole tab 32 that allows current to pass directly. During the charging and discharging process, lithium ions can be more smoothly deintercalated and intercalated, reducing the risk of lithium plating and improving the conductivity between the first end cover 2 and the first pole tab 32.

[0200] In some embodiments, as shown in FIG6 , the battery cell 100 further includes an insulating component 5 ′, which is disposed between the first end cover 2 and the shell 1 to achieve insulation between the first end cover 2 and the shell 1 . The insulating component 5 ′ includes: a first insulating member 5 ; and a second insulating member 6 , which is disposed radially inwardly of the first insulating member 5 . The heat-resistant temperature of the second insulating member 6 is higher than that of the first insulating member 5 .

[0201] The first insulating member 5 is located between the first portion 111 and the first end cap 2. The shape of the first insulating member 5 may be consistent with that of the first portion 111. To increase the creepage distance between the first portion 111 and the first end cap 2, the edge of the first insulating member 5 may extend beyond the edge of the first portion 111. The second insulating member 6 is disposed corresponding to the second portion 112 and may be consistent with that of the second portion 112. To increase the creepage distance between the second portion 112 and the first end cap 2, the edge of the second insulating member 6 may extend beyond the edge of the second portion 112.

[0202] For example, the first insulating member 5 is made of rubber material, and the second insulating member 6 is made of polybutylene terephthalate (PBT) material, which has a temperature resistance of about 300° C., which is higher than that of rubber material. Alternatively, other high-temperature resistant insulating materials may be used.

[0203] In this embodiment, the busbar is welded to the second portion 112 , which can prevent insulation failure caused by high temperature heat generated during the welding process, thereby improving the reliability of the battery cell 100 .

[0204] In some embodiments, the second insulating member 6 and the first insulating member 5 are connected at the joint position using a concave-convex structure 50 .

[0205] For example, as shown in FIG6 , the first insulating member 5 has a first protrusion 5A near the first end cap 2 , and the second insulating member 6 has a second protrusion 6A near the flange 11 . The first protrusion 5A and the second protrusion 6A overlap to form a concave-convex fitting structure 50 . The first protrusion 5A and the second protrusion 6A can employ an interference fit. Optionally, the first protrusion 5A and the second protrusion 6A can be positioned interchangeably.

[0206] This embodiment adopts a concave-convex structure 50 at the docking position of the second insulating member 6 and the first insulating member 5, which can enable the second insulating member 6 and the first insulating member 5 to fit tightly together, prevent the formation of a gap between the two and cause a short circuit between the flange 11 and the first end cover 2, and also improve the sealing effect.

[0207] In some embodiments, the Vickers hardness of the first insulating member 5 is lower than that of the second insulating member 6 , and the thickness of the first insulating member 5 between the first portion 111 and the first end cap 2 is greater than the maximum thickness of the second insulating member 6 .

[0208] When the first insulating member 5 and the second insulating member 6 are compressed together to the same thickness, the deformation of the first insulating member 5 is greater.

[0209] This embodiment takes into account the difficulty of achieving both sealing and high-temperature insulation with current insulating materials. Therefore, the first insulating member 5 is designed to have a lower Vickers hardness and a greater thickness. When the first and second insulating members 5, 6 are simultaneously squeezed between the flange 11 and the first end cap 2, the first insulating member 5 undergoes a significant deformation to achieve flush surfaces, resulting in a superior sealing effect. Furthermore, the second insulating member 6 also provides high-temperature insulation. When welding the busbar to the location of the second portion 112, this prevents insulation failure caused by the high temperature generated during welding, thereby improving the reliability of the battery cell 100.

[0210] In some embodiments, the flange 11 is configured to be formed by removing material at the first opening 12 .

[0211] The first opening 12 can be formed by punching the closed end of the receiving part (a blank of the housing 1 ).

[0212] This embodiment facilitates the formation of flanges 11 of any shape, and is also conducive to the formation of wider flanges 11, which can increase the welding contact area between the collector and the flange 11, improve welding reliability, reduce the difficulty of positioning during welding, and improve the flow capacity between the flange 11 and the collector. Moreover, the first opening 12 can be flexibly punched into the required shape to further meet the layout requirements of the welding track between the first end cover 2 and the first tab 32. In addition, compared with the rolling method, the flange 11 formed by removing material can ensure that the flange 11 is flat, is not affected by the shape of the battery cell 100 and the width of the flange 11, does not cause wrinkles on the flange 11, does not require flattening treatment, and can also ensure that the flange 11 is in reliable contact with the insulating component 5', thereby improving the sealing effect.

[0213] In some embodiments, as shown in Figure 4, the shell 1 includes a side wall 13 and a first end wall 14, the first end wall 14 is connected to the end of the side wall 13 opposite to the first opening 12, the side wall 13 has a second opening 15, the first end wall 14 is formed by a second end cover 4, and the second end cover 4 is used to close the second opening 15.

[0214] The side wall 13 has a first opening 12 and a second opening 15 at both ends along the axial direction. The first opening 12 is closed by the first end cover 2, and the second opening 15 is closed by the second end cover 4. The second end cover 4 forms the first end wall 14. The second end cover 4 and the side wall 13 can be connected by welding.

[0215] This embodiment is based on a structure in which a flange 11 is formed by removing material. As shown in Figures 8 and 9, the closed end of the container 1' needs to be punched to form a first opening 12. The container 1' includes a side wall 13 and a second end wall 16. The second end wall 16 is connected to one end of the side wall 13. The second end wall 16 can completely close the opening of the side wall 13, or partially close the opening of the side wall 13, but it is necessary to ensure that the second end wall 16 completely covers the flange 11, and the covering area is greater than the area of ​​the flange 11. Since a second end wall 16 is provided at one end of the side wall 13, a second opening 15 needs to be provided at the other end, and the second opening 15 is closed by a separate second end cover 4. This structure provides conditions for forming the flange 11 by removing material.

[0216] In some embodiments, as shown in FIG. 7A , the second end cap 4 is connected to the side wall 13 via a first weld 41 , which is formed between the outer edge of the second end cap 4 and the inner surface of the side wall 13 .

[0217] Among them, the second end cover 4 is a flat disc structure, the circumferential outer wall of the second end cover 4 cooperates with the end area of ​​the inner surface of the side wall 13, the outer surface of the second end cover 4 can be flush with the end surface of the side wall 13, and welding is performed on the outside of the second end cover 4.

[0218] This embodiment can simplify the structure of the second end cover 4 , and the second end cover 4 may not protrude from the end of the side wall 13 , which can further reduce the height of the battery cell 100 , thereby improving the energy density of the battery cell 100 .

[0219] In some embodiments, as shown in Figure 7B, the second end cover 4 is connected to the side wall 13 through a first weld 41. The second end cover 4 includes a first main body portion 43 and a bent portion 44. The first end of the bent portion 44 is connected to the outer edge of the first main body portion 43, and the second end of the bent portion 44 is covered with the end of the side wall 13. The first weld 41 is formed between the second end of the bent portion 44 and the end of the side wall 13.

[0220] The second end cap 4 has a bent portion 44 at its outer edge, causing the central region to be recessed inward relative to the edge region. The bent portion 44 has an L-shaped cross section, comprising a vertical portion and a horizontal portion connected to each other. The horizontal portion covers the end of the side wall 13, and the vertical portion adheres to the inner surface of the side wall 13. After the second end cap 4 is installed, it can be welded from the outer periphery of the side wall 13.

[0221] The second end cap 4 of this embodiment is provided with a bent portion 44, and the second end of the bent portion 44 and the end covering the side wall 13 can be used to position the second end cap 4 along the height direction of the battery cell 100, preventing the second end cap 4 from moving during welding without the need for additional tooling. Furthermore, if the pressure relief component 8 is provided on the second end cap 4, the central area of ​​the second end cap 4 is recessed inward, reducing the risk of damage to the pressure relief component 8 from external impact.

[0222] In some embodiments, as shown in Figures 13 and 14, the shell 1 includes a side wall 13 and a first end wall 14, the first end wall 14 is connected to the end of the side wall 13 opposite to the first opening 12, the flange 11 only includes a first portion 111, the first portion 111 is connected to the side wall 13, and the first end wall 14 serves as a second output pole.

[0223] The first end wall 14 and the side wall 13 may be integrally formed or connected by welding.

[0224] This embodiment can be used only to limit the electrode assembly 3 when the radial width of the flange 11 is narrow, and the first end wall 14 is used as the second output pole. This provides a larger area for the second output pole to connect the busbar, is also beneficial for positioning during the welding process, and can improve the reliability of the electrical connection.

[0225] In some embodiments, the flange 11 is configured to be formed by bending an end portion of the side wall 13 .

[0226] After the electrode assembly 3 is installed in the housing 1 and the first end cover 2 is mounted, the end wall of the side wall 13 can be bent toward the outer surface of the first end cover 2 .

[0227] In this embodiment, the flange 11 is formed by bending, and a shell 1 in which the side wall 13 and the first end wall 14 are integrally formed can be used. After the electrode assembly 3 is installed in the shell 1, it is directly bent into the flange 11 without the need for an additional process to form the first opening 12, which can simplify the process flow and improve assembly efficiency.

[0228] In some embodiments, the side wall 13 and the first end wall 14 are integrally formed.

[0229] Since the first opening 12 does not need to be formed by removing material from the closed-end container 1', the opening of the housing 1 directly forms the first opening 12, allowing the side wall 13 and the first end wall 14 to be formed integrally. Optionally, the side wall 13 and the first end wall 14 can also be welded.

[0230] In this embodiment, the side wall 13 and the first end wall 14 are formed integrally, which can save the additional process of connecting the first end wall 14 to the side wall 13, further simplify the process flow, and improve assembly efficiency.

[0231] In some embodiments, as shown in Figures 4 and 13, the shell 1 includes a side wall 13, the side wall 13 includes a second body portion 131 and a protrusion 132, the protrusion 132 protrudes toward the inside of the shell 1 relative to the second body portion 131, and the protrusion 132 is located between the first end cover 2 and the electrode body 31 in the height direction of the battery cell 100.

[0232] The raised portion 132 can be formed by roller groove sealing. The raised portion 132 and the second body portion 131 can have the same thickness. The raised portion 132 does not contact the first tab 32 to ensure insulation performance.

[0233] The side wall 13 may be provided with a raised portion 132 only at one end near the first end cap 2, with the other end directly connected to the second end cap 4 by welding. Alternatively, the side wall 13 and the first end wall 14 may be integrally formed, thereby reducing the overall height of the battery cell 100 and improving energy density. Alternatively, if the first end cap 2 and the second end cap 4 are provided at both ends of the side wall 13, both the first end cap 2 and the second end cap 4 may be secured by roller groove sealing, i.e., a raised portion 132 is provided at each end of the side wall 13.

[0234] This embodiment provides support for the edge position of the first end cover 2 by providing a protrusion 132 on the side wall 13, so that the protrusion 132 can support the first end cover 2 together with the first pole tab 32. When the first end cover 2 is subjected to external compression or the battery cell 100 is subjected to vibration force, the force on the first pole tab 32 can be reduced, the first pole tab 32 can be prevented from being deformed, and the reliability of the electrical connection between the first end cover 2 and the first pole tab 32 can be improved.

[0235] In some embodiments, the protrusion 132 extends to the radial inner side of the outer sidewall of the electrode body 31 .

[0236] For example, the surface of the protrusion 132 facing the first end cover 2 and the electrode body 31 can be flat to provide good support, and the portion of the protrusion 132 facing the first electrode tab 32 can be arc-shaped.

[0237] In this embodiment, the protrusion 132 extends to the radial inner side of the outer wall of the electrode body 31, so that the protrusion 132 can be supported between the electrode body 31 and the first end cover 2, thereby providing more stable support for the first end cover 2 and being able to maintain the height of the first pole tab 32, thereby improving the reliability of the electrical connection between the first pole tab 32 and the first end cover 2.

[0238] In some embodiments, the outer edge of the first electrode tab 32 and the outer sidewall of the electrode body 31 are retracted inward by a preset distance.

[0239] The outer edge of the first electrode tab 32 is radially retracted inward by a preset distance to form a step for accommodating the protrusion 132. The first electrode tab 32 can be formed into a step by die-cutting or by a step flattening process, that is, the first electrode tab 32 is continuously extended. After the electrode assembly 3 is formed, the step is formed by extrusion, which avoids waste of the electrode piece and reduces the scrap rate of the cut electrode tab. In addition, the electrode piece has a shorter electron transmission distance throughout the entire extended length range, which can improve the conductive performance.

[0240] In this embodiment, the outer edge of the first pole lug 32 is retracted inward by a preset distance, which allows the protrusion 132 to be designed with a larger extension length in the radial direction, so as to provide more stable support for the first end cover 2 and maintain the height of the first pole lug 32; it can also avoid excessive squeezing of the insulating material on the side wall of the first pole lug 32 when the protrusion 132 is formed during the assembly process, causing insulation failure; in addition, when the insulating component 5' wraps the edge area of ​​the inner surface of the first end cover 2, the first pole lug 32 can also avoid the insulating component 5'.

[0241] In some embodiments, as shown in Figure 6, the battery cell 100 also includes a third insulating member 9, and the third insulating member 9 includes a fourth segment 91 and a fifth segment 92. The fourth segment 91 is attached to the outer wall of the first pole tab 32, and the first end of the fifth segment 92 is connected to an end of the fourth segment 91 close to the root of the first pole tab 32, and the fifth segment 92 is attached to the area of ​​the end surface of the electrode body 31 where the first pole tab 32 is not provided.

[0242] For example, the third insulating member 9 may be an insulating film, or a coated insulating layer.

[0243] This embodiment can use the third insulating member 9 to cover the outer wall of the first electrode tab 32 and the area of ​​the end face of the electrode body 31 where the first electrode tab 32 is not provided, thereby preventing short circuit caused by contact with the protrusion 132 and improving the insulation reliability between the electrode assembly 3 and the shell 1.

[0244] In some embodiments, the third insulating member 9 further includes a sixth segment 93 , the sixth segment 93 covers an end region of the outer sidewall of the electrode body 31 , and a first end of the sixth segment 93 is connected to a second end of the fifth segment 92 .

[0245] The second end of the sixth segment 93 extends in the axial direction of the electrode body 31 in a direction away from the first electrode tab 32 , and the sixth segment 93 may cover the entire circumferential area of ​​the electrode body 31 .

[0246] In this embodiment, the sixth section 93 is provided to cover the end region of the outer side wall of the electrode body 31 , thereby improving the insulation reliability between the electrode body 31 and the side wall 13 and preventing short circuit.

[0247] In some embodiments, the third insulating member 9 further includes a seventh segment 94 , which is attached to the end surface of the first tab 32 near the outer edge, and a first end of the seventh segment 94 is connected to an end of the fourth segment 91 away from the root of the first tab 32 .

[0248] The second end of the seventh segment 94 extends inwardly along the radial direction of the electrode body 31 , and the sixth segment 93 can cover the outer edge region of the first electrode tab 32 .

[0249] This embodiment can cover the outer edge area of ​​the first pole tab 32 by providing the seventh section 94, and together with the fourth section 91, fully cover the first pole tab 32 to improve the insulation performance, and can also smooth and fit the outer edge area of ​​the first pole tab 32, so that the first end cover 2 and the end face of the first pole tab 32 can be better fitted.

[0250] In some embodiments, the material of the shell 1 includes steel, the material of the first end cover 2 includes aluminum, the first end cover 2 serves as the positive output pole, and the shell 1 serves as the negative output pole. Accordingly, the first pole ear 32 is the positive pole ear, and the second pole ear 33 is the negative pole ear; or the material of the shell 1 includes aluminum, the material of the first end cover 2 includes copper or steel, the first end cover 2 serves as the negative output pole, and the shell 1 serves as the positive output pole. Accordingly, the first pole ear 32 is the negative pole ear, and the second pole ear 33 is the positive pole ear.

[0251] In order to improve the rust-proof effect of the housing 1 , the outer surface may be nickel-plated.

[0252] In this embodiment, the polarity of the first output electrode and the second output electrode can be selected based on the material of the first end cap 2 to achieve matching materials for welding as much as possible and reduce the risk of leakage after welding. For example, if the material of the first end cap 2 includes aluminum, since the first end cap 2 is electrically connected to the first tab 32, the first tab 32 is also made of aluminum; if the material of the first end cap 2 includes copper or steel, since the first end cap 2 is electrically connected to the first tab 32, the first tab 32 is made of copper.

[0253] In some embodiments, the battery cell 100 is cylindrical.

[0254] For the cylindrical battery cell 100 , it is convenient to form the first opening 12 by removing material. Furthermore, if the flange 11 is formed by bending the end of the side wall 13 , wrinkles are not easily generated when rolling the flange 11 .

[0255] Secondly, the present application provides a method for manufacturing a battery cell, which, in some embodiments, includes:

[0256] Providing an assembly step: providing a housing 1, a first end cap 2, and an electrode assembly 3, wherein the housing 1 has a first opening 12, and the electrode assembly 3 includes an electrode body 31, a first electrode tab 32, and a second electrode tab 33, wherein the first electrode tab 32 and the second electrode tab 33 are led out from the electrode body 31 and have opposite polarities;

[0257] Electrode placement step: Place the electrode assembly 3 into the housing 1;

[0258] First sealing step: closing the first opening 12 with the first end cover 2 and insulating the first end cover 2 from the housing 1;

[0259] Electrical connection step: electrically connecting the first electrode tab 32 to the first end cover 2, and electrically connecting the second electrode tab 33 to the housing 1, wherein the first end cover 2 serves as the first output pole and the housing 1 serves as the second output pole.

[0260] The assembly step is performed first, the electrode placement step and the first sealing step are interchangeable depending on the embodiment, and the electrical connection step is performed last. For embodiments in which the flange 11 is formed by removing material, the first end cap 2 must be placed first to seal the first opening 12, and then the electrode assembly 3 must be installed into the housing 1. For embodiments in which the flange 11 is formed by bending, the electrode assembly 3 must be installed into the housing 1 first, and then the first end cap 2 must be placed. The end of the side wall 13 of the housing 1 is bent to form the flange 11 to limit the first end cap 2.

[0261] The battery cell 100 of this embodiment uses the first end cap 2 as the first output pole and the shell 1 as the second output pole, eliminating the need for electrode terminals. This can reduce the height of the battery cell 100, improve the energy density of the battery cell 100, reduce the number of parts, and reduce the process difficulty and production cost. Moreover, the end face and side face of the shell 1 can be used as the location for connecting the busbar, which can improve the flexibility when electrically connecting multiple battery cells 100.

[0262] In some embodiments, for the battery cell 100 shown in FIG4 , with reference to FIG8 and FIG9 , the manufacturing method of the present application further includes:

[0263] A container 1 ′ is provided, wherein the container 1 ′ has a side wall 13 and a second end wall 16 , wherein the second end wall 16 is connected to an end of the side wall 13 ;

[0264] A first opening 12 is formed by removing material from the second end wall 16 . A flange 11 is formed on the outer side of the first opening 12 . The flange 11 is used to limit the movement of the first end cover 2 in a direction away from the electrode assembly 3 .

[0265] These two steps are performed before the assembly step. As shown in Figure 8 , the container 1' is the blank that forms the housing 1. One end of the container 1' is closed by a second end wall 16, and the other end is open. As shown in Figure 9 , the second end wall 16 is punched from either the outside or inside of the container 1'. The removed material forms the first opening 12, and the remaining area on the second end wall 16 forms a flange 11, which can be of any shape.

[0266] This embodiment facilitates the formation of flanges 11 of any shape, and is also conducive to the formation of wider flanges 11, which can increase the welding contact area between the collector and the flange 11, improve welding reliability, reduce the difficulty of positioning during welding, and improve the flow capacity between the flange 11 and the collector. Moreover, the first opening 12 can be flexibly punched into the required shape to further meet the layout requirements of the welding track between the first end cover 2 and the first tab 32. In addition, compared with the rolling method, the flange 11 formed by removing material can ensure that the flange 11 is flat, is not affected by the shape of the battery cell 100 and the width of the flange 11, does not cause wrinkles on the flange 11, does not require flattening treatment, and can also ensure that the flange 11 is in reliable contact with the insulating component 5', thereby improving the sealing effect.

[0267] In some embodiments, as shown in FIG10 and FIG11 , the container 1 ′ has a second opening 15 , and the second opening 15 is opposite to the second end wall 16 . The first sealing step includes:

[0268] Before the electrode placement step, the first end cap 2 is placed into the receiving member 1 ′ through the second opening 15 , so that the first end cap 2 closes the first opening 12 .

[0269] In this embodiment, for the structure in which the flange 11 is formed by removing material, the first end cap 2 can be placed in the second opening 15 at the other end of the container 1 ′ to close the first opening 12 , and then the electrode assembly 3 can be placed in, so that the first end cap 2 can be installed smoothly.

[0270] In some embodiments, as shown in FIG10 and FIG11 , the battery cell 100 further includes an insulating component 5 ′, which is disposed between the first end cap 2 and the housing 1 to achieve insulation between the first end cap 2 and the housing 1 . The first sealing step further includes:

[0271] The insulating component 5 ′ is placed into the receiving part 1 ′ having the first opening 12 .

[0272] This step can be performed before placing the first end cover into the container 1 ′, or the insulating component 5 ′ can be installed on the first end cover 2 before placing the insulating component 5 ′ and the first end cover 2 into the container 1 ′ together.

[0273] In this embodiment, for the structure in which the flange 11 is formed by removing material, the second opening 15 at the other end of the receiving member 1 ′ can be used to place the insulating component 5 ′ so as to achieve insulation from the housing 1 after the first end cover 2 is placed.

[0274] In some embodiments, as shown in FIG12 , after the insulating component 5 ′ and the first end cover 2 are placed, the side wall 13 of the container 1 ′ is rolled to form a protrusion 132 , which protrudes toward the inside of the shell 1 to limit the first end cover 2 .

[0275] The outer side of the side wall 13 may be rolled by a roller cutter.

[0276] After the protrusion 132 is formed by rolling, this embodiment can limit the position of the first end cap 2 and the insulating component 5', preventing the first end cap 2 from shifting, and ensuring good positioning after the electrode assembly 3 is installed. If the insulating component 5' extends beyond the inner surface of the first end cap 2 on the side, the protruding portion of the insulating component 5' can be bent during rolling until it contacts the inner surface of the first end cap 2, thereby achieving insulation between the protrusion 132 and the first end cap 2.

[0277] In some embodiments, as shown in FIG13 and FIG14 , the manufacturing method of the present application further includes a second sealing step, which includes:

[0278] After the first sealing step and the electrode placement step, the second opening 15 is closed by the second end cap 4 .

[0279] After the electrode assembly 3 is placed in this embodiment, the second opening 15 is closed by the second end cap 4, thereby enabling installation of all components. The second end cap 4 can be connected to the side wall 13 by welding. The second opening 15 is closed by the separate second end cap 4, which provides conditions for forming the flange 11 by removing material.

[0280] In some embodiments, as shown in FIG13 and FIG14 , the housing 1 includes a side wall 13 and a first end wall 14 , wherein the first end wall 14 is connected to an end of the side wall 13 opposite to the first opening 12 , and the first sealing step includes:

[0281] After the electrode placement step, the first end cap 2 is covered on the first electrode tab 32 and the end of the side wall 13 is bent to form a flange 11. The flange 11 is used to limit the movement of the first end cap 2 away from the electrode assembly 3 so that the first end cap 2 closes the first opening 12.

[0282] In this embodiment, the flange 11 is formed by bending, and a shell 1 in which the side wall 13 and the first end wall 14 are integrally formed can be used. After the electrode assembly 3 is installed in the shell 1, it is directly bent into the flange 11 without the need for an additional process to form the opening 12, which can simplify the process flow and improve assembly efficiency.

[0283] In some embodiments, the step of bending the end of the side wall 13 to form the flange 11 includes:

[0284] The end of the side wall 13 is bent by upsetting to form a flange 11 .

[0285] Before bending to form the flange 11, the first end cap 2 can be placed on the surface of the first tab 32, and then the insulating component 5' can be placed therein, followed by roller-grooving to form the protrusion 132 and the flange 11. Alternatively, the insulating component 5' can be mounted on the first end cap 2, and then the insulating component 5' and the first end cap 2 can be installed together into the housing 1, followed by roller-grooving to form the protrusion 132 and the flange 11.

[0286] This embodiment forms the flange 11 by upsetting, which has a simple process and can select a suitable insulating component 5' according to the shape of the flange 11 to achieve comprehensive improvement in terms of improving insulation performance, improving sealing performance, and increasing creepage distance. For example, by providing a high-temperature resistant second insulating component 6, it is possible to avoid affecting the insulation between the first end cover 2 and the flange 11 when welding the busbar; by providing an insulating component 5' composed of a first insulating component 5 and a second insulating component 6, and the hardness of the first insulating component 5 is lower than that of the second insulating component 6, the sealing between the first end cover 2 and the flange 11 can be improved; by extending the insulating component 5' beyond the inner edge of the flange 11, the creepage distance can be increased.

[0287] In some embodiments, the step of bending the end of the side wall 13 to form the flange 11 includes:

[0288] Insulation glue is provided on the inner surface of the side wall 13 located at the first opening 12;

[0289] The end of the side wall 13 is hot pressed to form a flange 11 , and the flange 11 and the first end cover 2 are bonded by insulating glue. After the insulating glue solidifies, an insulating component 5 ′ is formed. The insulating component 5 ′ is used to achieve insulation between the first end cover 2 and the housing 1 .

[0290] Among them, the insulating glue can be made of polypropylene (PP) material, etc. The insulating glue can achieve sealing and insulation at the same time.

[0291] This embodiment can achieve greater connection strength by adopting thermal composite sealing, and can eliminate the need to form the protrusion 132 by rolling grooves. Not providing the protrusion 132 is beneficial for reducing the height of the first electrode tab 32, thereby reducing the overall height of the battery cell 100, thereby improving the energy density of the battery cell 100.

[0292] Some specific embodiments of the battery cell 100 and the manufacturing method thereof of the present application are given below.

[0293] In the first embodiment, as shown in Figures 4 to 7B , a battery cell 100 includes a housing 1, a first end cap 2, a second end cap 4, an electrode assembly 3, and an insulating component 5'. The housing 1 includes a sidewall 13 and a first end wall 14. The first end wall 14 is located at the end of the sidewall 13 opposite the first opening 12, and the second end cap 4 serves as the first end wall 14. The electrode assembly 3 is located within the housing 1 and includes an electrode body 31, a first electrode tab 32, and a second electrode tab 33. The first electrode tab 32 and the second electrode tab 33 extend from the electrode body 31 and have opposite polarities. The first electrode tab 32 is electrically connected to the first end cap 2, and the second electrode tab 33 is electrically connected to the housing 1. The first end cap 2 serves as the first output pole, and the housing 1 serves as the second output pole.

[0294] The flange 11 is formed by removing material from the first opening 12, for example by punching. The flange 11 includes a first portion 111 and a second portion 112. The first portion 111 is connected to the sidewall 13, and the second portion 112 is connected to the first portion 111 and located radially inward of the first portion 111. The second portion 112 serves as the second output pole. This structure positions the first and second output poles at the same end of the battery cell 100. The pressure relief component 8 is provided on the second end cap 4 to reduce the impact of high-temperature exhaust on the side of the manifold during thermal runaway pressure relief, thereby preventing large-scale short circuits or high-voltage sparks in the battery 200.

[0295] As shown in Figure 5A, the second portion 112 includes a plurality of protrusions 112' spaced apart along the circumference of the housing 1. As shown in Figure 5B, the second portion 112 includes a single protrusion 112' that extends continuously along a portion of the circumference of the housing 1. The first end cap 2 and the first tab 32 are electrically connected by welding, forming a second weld 22. The weld path can be distributed over the area bounded by the inner edge of the second portion 112, the side edge of the second portion 112, and the inner edge of the first portion 111. The second tab 33 is electrically connected to the second end cap 4 by welding, forming a third weld 42.

[0296] The insulating component 5' is disposed between the first end cap 2 and the housing 1 to provide insulation between the two components. The insulating component 5' comprises a first insulating member 5 and a second insulating member 6. The second insulating member 6 is disposed radially inward of the first insulating member 5 and has a higher heat resistance than the first insulating member 5. A concave-convex structure 50 can be used to connect the second insulating member 6 and the first insulating member 5. The Vickers hardness of the first insulating member 5 can be lower than that of the second insulating member 6, and the thickness of the first insulating member 5 located between the first portion 111 and the first end cap 2 is greater than the maximum thickness of the second insulating member 6.

[0297] The manufacturing method of the battery cell 100 is as follows:

[0298] 1. As shown in FIG8 , a container 1 ' is stamped or drawn. The container 1 ' has a sidewall 13 and a second end wall 16. The second end wall 16 is connected to the end of the sidewall 13. As shown in FIG9 , material is removed from the second end wall 16 to form a first opening 12. A flange 11 is formed outside the first opening 12. The flange 11 is used to limit the movement of the first end cap 2 away from the electrode assembly 3.

[0299] 2. Wind the positive electrode sheet, the negative electrode sheet and the separator to form the electrode assembly 3, flatten the first electrode tab 32 and the second electrode tab 33, press a step on the side of the first electrode tab 32, and cover the step position with the third insulating member 9.

[0300] 3. As shown in FIG. 10 and FIG. 11 , place the first insulating member 5 and the second insulating member 6 into the container 1 ′ from the second opening 15 , and place the first end cover 2 into the container 1 ′ from the second opening 15 so that the first end cover 2 closes the first opening 12 .

[0301] 4. As shown in FIG12 , a roller cutter is used to form a protrusion 132 on the side wall 13 of the container 1 ′ at the required position by means of a roller groove, so as to limit the first end cover 2 and shape the container 1 ′ after the roller groove.

[0302] 5. Place the electrode assembly 3 into the container 1 ′ through the second opening 15 so that the first electrode tab 32 contacts the first end cap 2 , close the second opening 15 with the second end cap 4 , and connect the second end cap 4 and the side wall 13 by welding.

[0303] 6. Welding the first end cap 2 and the first electrode tab 32 through the first opening 12 can also be performed before welding the second end cap 4 and the side wall 13. Furthermore, welding the second end cap 4 and the second electrode tab 33 from the outside of the second end cap 4 can also be performed before welding the second end cap 4 and the side wall 13. The welding steps for the first electrode tab 32 and the second electrode tab 33 are interchangeable.

[0304] 7. After vacuum dehydration of the battery cell 100 , electrolyte is poured through the injection hole 21 on the first end cover 2 , and the electrolyte is formed, the sealing member 7 is welded to form a fourth weld 23 .

[0305]

[0306] In the second embodiment, as shown in Figure 13, the flange 11 differs from the first embodiment in that it comprises only a first portion 111, formed by bending the end of the side wall 13, for example, by roll-grooving. Because the flange 11 is relatively narrow in radial direction, the second output pole is extended from the first end wall 14 of the housing 1, and the flange 11 only serves to position the first end cap 2. The side wall 13 and first end wall 14 can be integrally formed, and the side wall 13 also has a raised portion 132.

[0307] The manufacturing method of the battery cell 100 is as follows:

[0308] 1. Provide a housing 1 having a side wall 13 and a first end wall 14 .

[0309] 2. Place the second tab 33 of the electrode assembly 3 downward into the housing 1.

[0310] 3. Place the first end cap 2 on the first electrode tab 32 and install the insulating component 5 ′.

[0311] 4. Roll grooves on the side wall 13 to form a raised portion 132 . The raised portion 132 is located between the first end cover 2 and the electrode body 31 .

[0312] In the third embodiment, as shown in FIG14 , the difference from the second embodiment is that the side wall 13 of the shell 1 does not need to be formed with the protrusion 132 by roller groove sealing. The step of bending the end of the side wall 13 to form the flange 11 includes: first, providing an insulating glue on the inner surface of the side wall 13 located at the first opening 12; second, hot pressing the end of the side wall 13 to form the flange 11, and bonding the flange 11 and the first end cover 2 with the insulating glue. After the insulating glue solidifies, an insulating component 5' is formed. The insulating component 5' is used to achieve insulation between the first end cover 2 and the shell 1.

[0313] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and components may be substituted with equivalents without departing from the scope of the present application. In particular, the various technical features described in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present application is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions within the scope of the claims.

Claims

1. A battery cell, comprising: A housing (1) having a first opening (12); A first end cover (2) that closes the first opening (12) and is insulated from the housing (1); and An electrode assembly (3) is arranged in the housing (1), the electrode assembly (3) comprising an electrode body (31), a first pole lug (32) and a second pole lug (33), the first pole lug (32) and the second pole lug (33) being led out from the electrode body (31) and having opposite polarities, the first pole lug (32) being electrically connected to the first end cover (2), and the second pole lug (33) being electrically connected to the housing (1); The first end cover (2) serves as a first output pole, and the housing (1) serves as a second output pole.

2. The battery cell according to claim 1, wherein: The first pole lug (32) and the second pole lug (33) are respectively led out from two ends of the electrode body (31); the shell (1) comprises a side wall (13) and a first end wall (14); the first end wall (14) is connected to an end of the side wall (13) opposite to the first opening (12); and the second pole lug (33) is electrically connected to the first end wall (14).

3. The battery cell according to claim 2, wherein: The first pole lug (32) is directly connected to the first end cover (2); and / or the second pole lug (33) is directly connected to the first end wall (14).

4. The battery cell according to any one of claims 1 to 3, wherein: The shell (1) is provided with a flange (11) at the first opening (12), and the flange (11) is used to limit the movement of the first end cover (2) in a direction away from the electrode assembly (3).

5. The battery cell according to claim 4, wherein: The flange (11) serves as the second output pole.

6. The battery cell according to claim 5, wherein: The housing (1) comprises a side wall (13) and a first end wall (14); the first end wall (14) is connected to an end of the side wall (13) away from the first opening (12); and a pressure relief component (8) is provided on the first end wall (14); the pressure relief component (8) is used to relieve pressure when the pressure in the battery cell (100) exceeds a preset threshold.

7. The battery cell according to any one of claims 4 to 6, further comprising an insulating component (5') provided between the first end cover (2) and the shell (1) for achieving insulation between the first end cover (2) and the shell (1).

8. The battery cell according to claim 7, wherein: The insulating component (5') is at least partially disposed between the flange (11) and the first end cover (2), and extends beyond the inner edge of the flange (11).

9. The battery cell according to claim 7 or 8, wherein: The shell (1) comprises a side wall (13), the insulating component (5') comprises a first insulating component (5), the first insulating component (5) comprises a first section (51) and a second section (52), the first section (51) is located between the flange (11) and the first end cover (2), the second section (52) is connected to the first section (51), and the second section (52) is located between the outer edge of the first end cover (2) and the side wall (13).

10. The battery cell according to claim 9, wherein: The first insulating member (5) comprises a third section (53), the third section (53) being connected to an end of the second section (52) away from the first section (51), and the third section (53) being attached to a surface of the first end cover (2) close to the first pole lug (32).

11. The battery cell according to any one of claims 4 to 10, wherein: The shell (1) comprises a side wall (13); the flange (11) comprises a first portion (111) and a second portion (112); the first portion (111) is connected to the side wall (13); the second portion (112) is connected to the first portion (111) and is located radially inward of the first portion (111); and the second portion (112) serves as the second output pole.

12. The battery cell according to claim 11, wherein: The second portion (112) includes a plurality of protrusions (112'), and the plurality of protrusions (112') are arranged at intervals along the circumference of the housing (1); or The second portion (112) includes a protruding portion (112'), and the protruding portion (112') continuously extends along a portion of the circumference of the housing (1).

13. The battery cell according to claim 11 or 12, wherein: The first end cover (2) and the first pole lug (32) are welded, and the welding track is distributed in an area surrounded by an inner edge of the second part (112), a side edge of the second part (112) and an inner edge of the first part (111).

14. The battery cell according to any one of claims 11 to 13, further comprising an insulating component (5'), which is arranged between the first end cover (2) and the shell (1) to achieve insulation between the first end cover (2) and the shell (1), and the insulating component (5') comprises: A first insulating member (5); and The second insulating member (6) is arranged radially inward of the first insulating member (5), and the heat-resistant temperature of the second insulating member (6) is higher than the heat-resistant temperature of the first insulating member (5).

15. The battery cell according to claim 14, wherein: The butt joint position between the second insulating member (6) and the first insulating member (5) is matched with a concave-convex structure (50).

16. The battery cell according to claim 14 or 15, wherein: The Vickers hardness of the first insulating member (5) is lower than the Vickers hardness of the second insulating member (6), and the thickness of the first insulating member (5) located between the first portion (111) and the first end cover (2) is greater than the maximum thickness of the second insulating member (6).

17. The battery cell according to any one of claims 11 to 16, wherein: The flange (11) is configured to be formed by removing material at the first opening (12).

18. The battery cell according to any one of claims 11 to 17, wherein: The shell (1) comprises a side wall (13) and a first end wall (14), wherein the first end wall (14) is connected to an end of the side wall (13) opposite to the first opening (12), the side wall (13) has a second opening (15), the first end wall (14) is formed by a second end cover (4), and the second end cover (4) is used to close the second opening (15).

19. The battery cell according to claim 18, wherein: The second end cover (4) is connected to the side wall (13) via a first weld (41), and the first weld (41) is formed between the outer edge of the second end cover (4) and the inner surface of the side wall (13).

20. The battery cell according to claim 18, wherein: The second end cover (4) is connected to the side wall (13) via a first weld (41); the second end cover (4) comprises a first main body portion (43) and a bent portion (44); a first end of the bent portion (44) is connected to an outer edge of the first main body portion (43); a second end of the bent portion (44) is connected to an end portion covering the side wall (13); and the first weld (41) is formed between the second end of the bent portion (44) and the end portion of the side wall (13).

21. The battery cell according to any one of claims 4 to 10, wherein: The shell (1) comprises a side wall (13) and a first end wall (14), the first end wall (14) being connected to an end of the side wall (13) opposite to the first opening (12), the flange (11) comprising only a first portion (111), the first portion (111) being connected to the side wall (13), and the first end wall (14) serving as the second output pole.

22. The battery cell according to claim 21, wherein: The flange (11) is configured to be formed by bending the end of the side wall (13).

23. The battery cell according to claim 21, wherein: The side wall (13) and the first end wall (14) are formed integrally.

24. The battery cell according to any one of claims 1 to 23, wherein: The shell (1) comprises a side wall (13), the side wall (13) comprises a second body portion (131) and a protruding portion (132), the protruding portion (132) protrudes toward the inside of the shell (1) relative to the second body portion (131), and the protruding portion (132) is located between the first end cover (2) and the electrode body (31) in the height direction of the battery cell (100).

25. The battery cell according to claim 24, wherein: The protrusion (132) extends to the radial inner side of the outer side wall of the electrode body (31).

26. The battery cell according to any one of claims 1 to 25, wherein: The outer edge of the first electrode tab (32) and the outer side wall of the electrode body (31) are retracted inwardly by a preset distance.

27. The battery cell according to claim 26 further includes a third insulating member (9), the third insulating member (9) includes a fourth section (91) and a fifth section (92), the fourth section (91) is attached to the outer wall of the first pole lug (32), the first end of the fifth section (92) is connected to an end of the fourth section (91) close to the root of the first pole lug (32), and the fifth section (92) is attached to the end surface of the electrode body (31) where the first pole lug (32) is not provided.

28. The battery cell according to claim 27, wherein: The third insulating member (9) further includes a sixth section (93), the sixth section (93) covering the end region of the outer side wall of the electrode body (31), and a first end of the sixth section (93) connected to a second end of the fifth section (92).

29. The battery cell according to claim 27 or 28, wherein: The third insulating member (9) further comprises a seventh section (94), wherein the seventh section (94) is attached to an area of ​​the end surface of the first pole lug (32) close to the outer edge, and a first end of the seventh section (94) is connected to an end of the fourth section (91) away from the root of the first pole lug (32).

30. The battery cell according to any one of claims 1 to 29, wherein: The material of the shell (1) includes steel, the material of the first end cover (2) includes aluminum, the first end cover (2) serves as a positive output electrode, and the shell (1) serves as a negative output electrode; or The material of the shell (1) includes aluminum, the material of the first end cover (2) includes copper or steel, the first end cover (2) serves as a negative output electrode, and the shell (1) serves as a positive output electrode.

31. The battery cell according to any one of claims 1 to 30, wherein the battery cell (100) is cylindrical.

32. A battery, comprising the battery cell (100) according to any one of claims 1 to 31.

33. An electrical device, comprising the battery cell (100) according to any one of claims 1 to 31 and / or the battery (200) according to claim 30, for providing electrical energy to the electrical device.

34. A method for manufacturing a battery cell, comprising: Providing an assembly step: providing a shell (1), a first end cover (2) and an electrode assembly (3), wherein the shell (1) has a first opening (12), and the electrode assembly (3) comprises an electrode body (31), a first electrode tab (32) and a second electrode tab (33), wherein the first electrode tab (32) and the second electrode tab (33) are led out from the electrode body (31) and have opposite polarities; Electrode placement step: placing the electrode assembly (3) into the housing (1); A first sealing step: closing the first opening (12) by means of the first end cover (2), and insulating the first end cover (2) from the housing (1); Electrical connection step: electrically connecting the first pole lug (32) to the first end cover (2), and electrically connecting the second pole lug (33) to the shell (1), wherein the first end cover (2) serves as a first output pole and the shell (1) serves as a second output pole.

35. The manufacturing method according to claim 34, further comprising: A container (1') is provided, the container (1') having a side wall (13) and a second end wall (16), the second end wall The end wall (16) is connected to the end of the side wall (13); The first opening (12) is formed by removing material from the second end wall (16), and a flange (11) is formed on the outer side of the first opening (12), wherein the flange (11) is used to limit the movement of the first end cover (2) in a direction away from the electrode assembly (3).

36. The manufacturing method according to claim 35, wherein: The container (1') has a second opening (15), the second opening (15) is opposite to the second end wall (16), and the first sealing step includes: Before the electrode placement step, the first end cap (2) is placed into the receiving member (1') through the second opening (15), so that the first end cap (2) closes the first opening (12).

37. The manufacturing method according to claim 36, wherein the battery cell (100) further comprises an insulating component (5') disposed between the first end cover (2) and the housing (1) for achieving insulation between the first end cover (2) and the housing (1), and the first sealing step further comprises: The insulating component (5') is placed in the receiving part (1') having the first opening (12).

38. According to the manufacturing method of claim 37, after placing the insulating component (5') and the first end cover (2), the side wall (13) of the container (1') is rolled to form a protrusion (132), and the protrusion (132) protrudes toward the inner side of the shell (1) to limit the first end cover (2).

39. The manufacturing method according to any one of claims 37 to 38, further comprising a second sealing step, wherein the second sealing step comprises: After the first sealing step and the electrode inserting step, the second opening (15) is closed by a second end cap (4).

40. The manufacturing method according to claim 34, wherein: The housing (1) comprises a side wall (13) and a first end wall (14), wherein the first end wall (14) is connected to an end of the side wall (13) opposite to the first opening (12), and the first sealing step comprises: After the electrode placement step, the first end cover (2) is covered on the first electrode ear (32), and the end of the side wall (13) is bent to form a flange (11), and the flange (11) is used to limit the movement of the first end cover (2) in a direction away from the electrode assembly (3), so that the first end cover (2) closes the first opening (12).

41. The manufacturing method according to claim 40, wherein: The step of bending the end of the side wall (13) to form a flange (11) comprises: The end of the side wall (13) is bent by upsetting to form the flange (11).

42. The manufacturing method according to claim 40, wherein: The step of bending the end of the side wall (13) to form a flange (11) comprises: An insulating glue is provided on the inner surface of the side wall (13) located at the first opening (12); The end of the side wall (13) is subjected to hot pressing to form the flange (11), the insulating adhesive is used to bond the flange (11) and the first end cover (2), and the insulating adhesive is solidified to form an insulating component (5'), and the insulating component (5') is used to achieve insulation between the first end cover (2) and the shell (1).

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