Cover plate assembly and battery module

Abstract

This application discloses a cover plate assembly and a battery module, wherein: a first terminal post passes through a first mounting hole in a first cover plate body; a second terminal post passes through a second mounting hole in a second cover plate body; a first support member is located on the outer side of the first cover plate body, and the portion of the first terminal post extending out of the first mounting hole is fitted into and welded to the through hole of the first support member; a second support member is located on the outer side of the second cover plate body, and the portion of the second terminal post extending out of the second mounting hole is fitted into and welded to the through hole of the second support member; the second terminal post and the first terminal post are coaxially welded, and / or, the first conductive area in the first support member and the second conductive area in the second support member are coaxially welded. This application eliminates the busbar between adjacent cells, which can reduce the connection resistance and number of parts between adjacent cells, reduce the number of welding operations, optimize the manufacturing process, and improve the connection reliability between adjacent cells.

Description

Technical Field

[0001] This application relates to the field of new energy technology, and in particular to a cover plate assembly and a battery module incorporating the cover plate assembly. Background Technology

[0002] In existing technology, adjacent battery cells have terminals on their cover plates. Terminals of different cells are typically bridging each other via busbars, and mechanical fixation between the busbars and terminals, as well as electrical conduction between terminals, are achieved through welding. A terminal is generally a metal conductive terminal led out from the battery cell, connected to the internal electrode assembly of the cell, and located in the cover plate (either protruding or not protruding from the outer side of the cover plate), used for external connection. However, the presence of busbars inevitably leads to increased resistance, numerous components, poor reliability, and cumbersome welding processes. Summary of the Invention

[0003] In view of this, the purpose of this application is to provide a cover plate assembly and a battery module that eliminates the bus between adjacent cells, thereby reducing the connection resistance and number of parts between adjacent cells, reducing the number of welding operations, optimizing the manufacturing process, and improving the connection reliability between adjacent cells.

[0004] To achieve the above objectives, this application provides the following technical solution: A cover plate assembly for mounting between a first electrode group of a first battery cell and a second electrode group of a second battery cell, the cover plate assembly comprising: The first cover plate body is provided with a first mounting hole; The second cover plate body is provided with a second mounting hole; the outer side surface of the first cover plate body and the outer side surface of the second cover plate body are arranged opposite to each other and maintain a preset distance greater than zero; The first pole post is inserted into the first mounting hole and is insulated from the first cover plate body; The second pole post passes through the second mounting hole and is insulated from the second cover plate body; The first support member is located on the outer side of the first cover plate body and is electrically isolated from and axially limited thereto; the portion of the first pole post extending out of the first mounting hole is fitted into the through hole of the first support member and welded thereto; The second support member is located on the outer side of the second cover plate body and is electrically isolated from and axially limited thereto; the portion of the second pole post extending out of the second mounting hole is fitted into the through hole of the second support member and welded thereto; Wherein: the second pole post and the first pole post are coaxially welded, and / or, the first conductive area in the first support member and the second conductive area in the second support member are coaxially welded.

[0005] Optionally, in the above-described cover plate assembly, the first pole post includes: The first column portion passes through the first mounting hole and is electrically isolated from the first cover plate body; The first limiting protrusion is arranged around the periphery of the pole post and protrudes from the circumferential sidewall of the first column body. It is located outside the first mounting hole and is electrically isolated from the inner side of the first cover plate body and is axially limited.

[0006] Optionally, in the above-described cover plate assembly, the second pole post includes: The second column portion passes through the second mounting hole and is electrically isolated from the second cover plate body; The second limiting protrusion is arranged around the pole post in the circumferential direction and protrudes from the circumferential side wall of the second column body. It is located outside the second mounting hole and is electrically isolated from the inner side of the second cover plate body and is axially limited.

[0007] Optionally, in the above-described cover plate assembly, the first support member includes a first welding ring and a first plastic part, wherein: the first welding ring is the first conductive area and is sleeved on the outside of the first pole and welded to it; the projection of the first welding ring on the first cover plate body is at least partially located radially outside the first mounting hole; at least a portion of the first plastic part is located between the outer side of the first cover plate body and the side of the first welding ring near the first cover plate body.

[0008] Optionally, in the above-mentioned cover plate assembly, the second support member includes a second welding ring and a second plastic part, wherein: the second welding ring is the second conductive area and is sleeved on the outside of the second pole and welded to it; the projection of the second welding ring on the second cover plate body is at least partially located on the radially outer side of the second mounting hole; at least part of the second plastic part is located between the outer side of the second cover plate body and the side of the second welding ring near the second cover plate body.

[0009] Optionally, in the above-mentioned cover plate assembly, the end of the first pole near the second cover plate body protrudes relative to the end face of the first welding ring near the second cover plate body, and the first pole and the first welding ring are fixed by fillet welding at the connection point. And / or, the end of the second pole near the first cover plate body protrudes relative to the end face of the second welding ring near the first cover plate body, and the second pole and the second welding ring are fixed by fillet welding at the connection.

[0010] Optionally, in the above-mentioned cover plate assembly, the end of the first pole near the second cover plate body is flush with the end of the first welding ring near the second cover plate body, and the first pole and the first welding ring are welded together at the connection point. And / or, the end of the second pole near the first cover plate body is flush with the end of the second welding ring near the first cover plate body, and the second pole and the second welding ring are welded together at the connection.

[0011] Optionally, in the above-mentioned cover plate assembly, the first pole post is provided with a first stepped groove along its circumference at one end near the second cover plate body, and the radial groove surface of the first stepped groove is flush with the surface of the first welding ring at one end near the second cover plate body and is fixed by seam welding. And / or, the second pole post is provided with a second stepped groove along its circumference at one end near the first cover plate body, and the radial groove surface of the second stepped groove is flush with the surface of the second welding ring at one end near the first cover plate body and is fixed by seam welding.

[0012] Optionally, in the above-mentioned cover plate assembly, a first stepped enlarged hole is provided at one end of the through hole of the first welding ring near the second cover plate body, and the bottom surface of the first stepped enlarged hole is welded to the end face of the first pole post. The second welding ring has a second stepped enlarged hole at one end near the first cover plate body, and the bottom surface of the second stepped enlarged hole is welded to the end face of the second pole post. The first welding ring and the second welding ring extend out of the first plastic part and the second plastic part respectively, are coaxially aligned and are fixed by seam welding.

[0013] Optionally, in the above-mentioned cover plate assembly, the first plastic part is disposed on the surface of the first welding ring by integral injection molding, and the first plastic part covers the part of the side of the first welding ring near the first cover plate body and the circumferential side of the first welding ring. And / or, the second plastic part is integrally injection molded onto the surface of the second welding ring, and the second plastic part covers a portion of the side of the second welding ring near the body of the second cover plate and the circumferential side of the second welding ring.

[0014] Optionally, in the above cover plate assembly, the material of the first pole is aluminum alloy, and the material of the second pole is copper-aluminum composite pole. The copper-aluminum composite pole includes a first connecting part for connecting the first pole and a second connecting part away from the first pole for connecting the second pole group. The material of the first connecting part includes aluminum, and the material of the second connecting part includes copper. Alternatively, the first electrode post is made of pure copper, and the second electrode post is made of copper-aluminum composite electrode post, including a first connecting part for connecting the first electrode post, and a second connecting part away from the first electrode post for connecting the second electrode group, wherein the first connecting part is made of copper and the second connecting part is made of aluminum.

[0015] Optionally, in the above-described cover plate assembly, the outer side of the first cover plate body and the outer side of the second cover plate body are electrically isolated by an air gap; And / or, the outer side of the first cover plate body and the outer side of the second cover plate body are electrically isolated by an insulating spacer; And / or, at least one of the outer surfaces of the first cover plate body and the second cover plate body is provided with an insulating layer.

[0016] A battery module includes a first battery cell and a second battery cell. The first battery cell includes a first housing and a first electrode group located in the first housing. The second battery cell includes a second housing and a second electrode group located in the second housing. A cover plate assembly as described above is provided between the first pole group and the second pole group; In the cover plate assembly, the end of the first pole away from the second cover plate body is electrically connected to the first tab of the first pole group, and the end of the second pole away from the first cover plate body is electrically connected to the second tab of the second pole group.

[0017] As can be seen from the above technical solutions, in the cover plate assembly and battery module provided in this application, when the first terminal and the second terminal are directly coaxially welded, they can form an integral terminal structure. Similarly, when the first support member sleeved outside the first terminal and the second support member sleeved outside the second terminal are directly coaxially welded, the first and second terminals can also be coaxially connected, thus forming an integral terminal structure. It is evident that the two cover plate bodies in this cover plate assembly share an integral terminal structure, meaning that the connection between the two cell electrode groups is achieved through an integral terminal structure. This reduces the use of connecting components such as busbars between the first and second terminals, which helps to reduce production costs and the overall weight of the battery module. When using this cover plate assembly to connect two adjacent cells during production, at least the busbar component and its welding process located between the first and second terminals in the prior art are eliminated. This achieves the goals of reducing the connection resistance and number of components between adjacent cells, reducing the number of welding operations, optimizing the manufacturing process, and improving the reliability of the connection between adjacent cells. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is an exploded view of a cover plate assembly provided in an embodiment of this application.

[0020] Figure 2 This is an isometric view of a cover plate assembly provided in an embodiment of this application.

[0021] Figure 3 This is a top view of a cover plate assembly provided in an embodiment of this application.

[0022] Figure 4 This is a side view of a cover plate assembly provided in an embodiment of this application.

[0023] Figure 5 This is a half-sectional view of a cover plate assembly provided in an embodiment of this application.

[0024] Figure 6 for Figure 5 Enlarged structural diagram of the welding position in the middle.

[0025] Figure 7 , Figure 8 , Figure 9 This is a schematic diagram of the seam weld position of a cover plate assembly provided in other embodiments of this application.

[0026] Figure 10 This is a half-sectional view of another cover plate assembly provided in the embodiments of this application (its second pole is a copper-aluminum composite pole and the end is not provided with a groove).

[0027] Figure 11 This is a half-sectional view of another cover plate assembly provided in the embodiments of this application (its second pole is a copper-aluminum composite pole with a groove at the end).

[0028] Figure 12 This is a flowchart illustrating a cover plate assembly method provided in an embodiment of this application.

[0029] in: 101 - First cover plate body, 110 - First mounting hole, 111 - First recessed groove 102 - Second cover plate body, 120 - Second mounting hole, 121 - Second recess, 201 - First plastic layer, 210 - Third mounting hole 202 - Second plastic layer, 220 - Fourth mounting hole 301 - First pole post, 311 - First post body, 312 - First limiting flange 302 - Second pole post, 321 - Second column body, 322 - Second limiting flange, 302a - First connecting part, 302b - Second connecting part, 3010 - First groove, 401 - First support component, 411 - First welding ring, 412 - First plastic part. 4121 - First insulating end face, 4122 - First limiting end face, 4123 - First cylindrical sidewall 402 - Second support component, 421 - Second welding ring, 422 - Second plastic part. 4221 - Second insulating end face, 4222 - Second limiting end face, 4223 - Second cylindrical sidewall 501 - First sealing structure, 511 - First insulating seal, 512 - Second insulating seal. 502 - Second sealing structure, 521 - Third insulating seal, 522 - Fourth insulating seal. Detailed Implementation

[0030] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0031] This application provides a cover plate assembly that can be disposed between the housings of two adjacent battery cells and connected to the electrode groups of the two battery cells respectively. For example, the cover plate assembly can be installed between the first electrode group of a first battery cell and the second electrode group of a second battery cell, and the cover plate assembly has an integral electrode post structure formed by welding, the two ends of which are electrically connected to the first electrode group and the second electrode group respectively.

[0032] Specifically, please see Figures 1 to 7 The cover plate assembly includes a first cover plate and a second cover plate, and an integrally formed pole post, which is constructed by welding. The pole post includes a first pole post 301 installed in the first cover plate and a second pole post 302 installed in the second cover plate. Wherein: The first cover plate is used to be installed at the end of the first housing of the first cell and is adapted to the end opening of the first housing. The first cover plate includes a first cover plate body 101 and a first plastic layer 201 located on the inner side of the first cover plate body 101 (i.e. the surface of the first cover plate body 101 near the first electrode group). The first cover plate body 101 is provided with a first mounting hole 110 and the first plastic layer 201 is provided with a third mounting hole 210 coaxial with the first mounting hole 110. The second cover plate is used to install on the end of the second housing of the second battery cell and is adapted to the end opening of the second housing. The second cover plate includes a second cover plate body 102 and a second plastic layer 202 located on the inner side of the second cover plate body 102 (i.e., the surface of the second cover plate body 102 near the second electrode group). The second cover plate body 102 is provided with a second mounting hole 120, and the second plastic layer 202 is provided with a fourth mounting hole 220 coaxial with the second mounting hole 120. The outer side of the second cover plate body 102 (i.e., the surface of the second cover plate body 102 near the first cover plate body 101) and the outer side of the first cover plate body 101 (i.e., the surface of the first cover plate body 101 near the second cover plate body 102) are arranged opposite to each other. Generally, the outer side of the second cover plate body 102 and the outer side of the first cover plate body 101 are parallel to each other and maintain a preset distance a greater than zero. The first pole post 301 is inserted into the first mounting hole 110 and is insulatedly connected to the first cover plate body 101; one end of the first pole post 301 is used to connect to the first pole group, and the other end is located between the outer side of the first cover plate body 101 and the outer side of the second cover plate body 102. The second pole post 302 is inserted into the second mounting hole 120 and is insulatedly connected to the second cover plate body 102; one end of the second pole post 302 is used to connect to the second pole group, and the other end is located between the outer side of the first cover plate body 101 and the outer side of the second cover plate body 102.

[0033] Specifically, the cover plate assembly also includes a first support member 401 and a second support member 402. The first support member 401 is located on the outer side of the first cover plate body 101 and is electrically isolated from and axially limited thereto (this axial direction is the axial direction of the first support member 401, and also the axial direction of the first pole post 301 and the first mounting hole 110, parallel to the thickness direction of the first cover plate body 101). The portion of the first pole post 301 extending out of the first mounting hole 110 is fitted into the through hole of the first support member 401 and welded thereto. The second support member 402 is located on the outer side of the second cover plate body 102 and is electrically isolated from and axially limited thereto (this axial direction is the axial direction of the second support member 402, and also the axial direction of the second pole post 302 and the second mounting hole 120, parallel to the thickness direction of the second cover plate body 102). The portion of the second pole post 302 extending out of the second mounting hole 120 is fitted into the through hole of the second support member 402 and welded thereto. Wherein: the second pole post 302 and the first pole post 301 are coaxially welded to form an integral pole post structure. The location of the weld between the second pole post 302 and the first pole post 301 can be found in [reference needed]. Figure 6 and Figure 7 The first welding position H1 in the first support member 401 and / or the first conductive area in the first support member 401 and the second conductive area in the second support member 402 are coaxially welded, which can also realize the coaxial connection and electrical connection of the first pole post 301 and the second pole post 302, thereby forming an integral pole post structure. At this time, the weld position between the first support member 401 and the second support member 402 can be seen from Figure 7 or Figures 9 to 11 The tenth welding position H10.

[0034] It should be noted that the axial direction of the first support member 401 in the axial limiting relationship with the first cover plate body 101 is the axial direction of the first support member 401, which is also the axial direction of the first pole post 301 and the first mounting hole 110. It is parallel to the thickness direction of the first cover plate body 101. Specifically, the top end face of the first support member 401 abuts against the first cover plate body 101, thereby limiting the axial movement of the first support member 401 through the first cover plate body 101. Similarly, the axial direction of the second support member 402 in the axial limiting relationship with the second cover plate body 102 is the axial direction of the second support member 402, which is also the axial direction of the second pole post 302 and the second mounting hole 120. It is parallel to the thickness direction of the second cover plate body 102. Specifically, the top end face of the second support member 402 abuts against the second cover plate body 102, thereby limiting the axial movement of the second support member 402 through the second cover plate body 102. Furthermore, it should be noted that the first pole post 301 is insulated from the first cover plate body 101. Specifically, the first pole post 301 and the first cover plate body 101 are structurally matched and mechanically connected through a direct connection (the surfaces of the parts at the connection point are coated with an insulating layer) or through an intermediate connector (the intermediate connector is an insulating component), while simultaneously ensuring electrical insulation between them. Similarly, the second pole post 302 is insulated from the second cover plate body 102. This means that the second pole post 302 and the second cover plate body 102 are structurally matched and mechanically connected through a direct connection (the surfaces of the parts at the connection point are coated with an insulating layer) or through an intermediate connector (the intermediate connector is an insulating component), while simultaneously ensuring electrical insulation between them. In summary, the first pole post 301 and the first cover plate body 101 are only structurally mechanically connected and electrically insulated from each other; and the second pole post 302 and the second cover plate body 102 are only structurally mechanically connected and electrically insulated from each other.

[0035] As can be seen, the cover plate assembly provided in this application embodiment can be used to connect two adjacent battery cells, so that two or more battery cells can be connected sequentially to form a battery module with a larger volume and larger battery capacity. In this cover plate assembly, when the first terminal 301 and the second terminal 302 are directly coaxially welded, they can form an integral terminal structure. When the first support member 401 sleeved outside the first terminal 301 and the second support member 402 sleeved outside the second terminal 302 are directly coaxially welded, the first terminal 301 and the second terminal 302 can also be coaxially connected, thereby forming an integral terminal structure. Thus, the connection between the first cover plate of the first battery cell and the second cover plate of the second battery cell is achieved through an integral terminal structure, thereby reducing the use of connecting parts such as busbars between the first and second terminals, which is beneficial to reducing production costs and the overall weight of the battery module. When using the cover plate assembly provided in this application to connect two adjacent battery cells during the production process, at least the busbar component and its welding process located between the first and second poles in the prior art are eliminated. This achieves the goals of reducing the connection resistance and number of components between adjacent battery cells, reducing the number of welding operations, optimizing the manufacturing process, and improving the connection reliability between adjacent battery cells. Specifically, the second pole 302 and the first pole 301 are coaxially welded to form an integral pole structure, and / or, the first conductive area in the first support member 401 and the second conductive area in the second support member 402 are coaxially welded so that the first pole 301 and the second pole 302 are coaxially connected and electrically connected through the support member to form an integral pole structure. This eliminates the need for the busbar between the first pole 301 and the second pole 302, allowing two adjacent battery cells to share an integral pole structure, which occupies less space and helps save material costs.

[0036] Please see Figure 1 In some embodiments, the first pole post 301 includes a first column portion 311 and a first limiting flange 312. The first column portion 311 passes through the first mounting hole 110 and is electrically isolated from the first cover plate body 101. The first limiting flange 312 surrounds the pole post circumferentially and protrudes from the circumferential sidewall of the first column portion 311. The first limiting flange 312 is located outside the first mounting hole 110, electrically isolated from the inner surface of the first cover plate body 101, and axially limited by the inner surface of the first cover plate body 101. Correspondingly, the second pole post 302 includes a second pole body portion 321 and a second limiting flange 322. The second pole body portion 321 passes through the second mounting hole 120 and is electrically isolated from the second cover plate body 102. The second limiting flange 322 surrounds the pole post circumferentially and protrudes from the circumferential sidewall of the second pole body portion 321. The second limiting flange 322 is located outside the second mounting hole 120, electrically isolated from the inner surface of the second cover plate body 102, and axially limited by the inner surface of the second cover plate body 102.

[0037] Further, please see Figure 1 , Figure 4 and Figure 5 The cover plate assembly also includes a first support member 401 and / or a second support member 402. Specifically: the first support member 401 is located outside the first mounting hole 110, fixedly connected to the first pole post 301, and electrically isolated and axially limited from the outer surface of the first cover plate body 101. This axial direction is the axial direction of the first support member 401, and generally also the axial direction of the first pole post 301 and the first mounting hole 110, and is parallel to the thickness direction of the first cover plate body 101. The second support member 402 is located outside the second mounting hole 120, fixedly connected to the second pole post 302, and electrically isolated and axially limited from the outer surface of the second cover plate body 102. This axial direction is the axial direction of the second support member 402, and generally also the axial direction of the second pole post 302 and the second mounting hole 120, and is parallel to the thickness direction of the second cover plate body 102.

[0038] In some embodiments, the first support member 401 is an annular structure. This annular structure is sleeved outside the first column portion 311, fixedly connected to (e.g., welded) to the first column portion 311, and fits against the outer surface of the first cover plate body 101. This allows the first support member 401 to axially limit and position the first pole post 301, which helps ensure the connection stability between the first pole post 301, the first cover plate, and the first pole group. In some embodiments, the first support member 401 includes a first welding ring 411 and a first plastic part 412: the first welding ring 411 is a first conductive area and is sleeved outside the first column portion 311 and welded to it; at least a portion of the first plastic part 412 is located between the outer surface of the first cover plate body 101 and the side of the first welding ring 411 near the first cover plate body 101, thereby electrically isolating the first pole post 301 from the first cover plate body 101. To improve the connection stability between the first electrode post 301 and the first cover plate body 101, and to avoid problems such as tilting, offsetting, or shaking of the first electrode post 301 relative to the first cover plate body 101, the projection of the first welding ring 411 on the first cover plate body 101 can be at least partially located radially outside the first mounting hole 110, so that the first support member 401 fits against the outer surface of the first cover plate body 101. For example, when the first welding ring 411 is a ring and the first mounting hole 110 is a circular hole, the diameter of the first welding ring 411 is larger than the diameter of the first mounting hole 110. Thus, the first support member 401, composed of the first welding ring 411 and the first plastic part 412, can stably mount the first electrode post 301 on the outer surface of the first cover plate body 101.

[0039] In a specific implementation, the first plastic part 412 can be an annular insulating gasket placed between the first welding ring 411 and the first cover plate body 101, or the first plastic part 412 can be a hollow structure sleeved on the outside of the first welding ring 411. For details, please refer to... Figure 1 ,as well as Figures 5 to 11 In any of the accompanying drawings, the first plastic part 412 includes a first insulating end face 4121, a first limiting end face 4122, and a first cylindrical sidewall 4123: the first insulating end face 4121 is located on the side of the first welding ring 411 close to the first cover plate body 101, that is, the first insulating end face 4121 is located between the first welding ring 411 and the first cover plate body 101; the first limiting end face 4122 is located on the side of the first welding ring 411 away from the first cover plate body 101, and the inner diameter of the first limiting end face 4122 is less than or equal to the inner diameter of the first insulating end face 4121, used to cover the annular protrusion of the first welding ring 411 and expose the connecting end of the first welding ring 411 for welding with the second welding ring 421; the first cylindrical sidewall 4123 covers the circumferential sidewall of the first welding ring 411, and its two ends are respectively connected to the outer side of the first insulating end face 4121 and the outer side of the first limiting end face 4122. In a specific implementation, the first plastic part 412 and the first welding ring 411 can be integrally injection molded to form a first composite welding ring. That is, the first plastic part 412 is integrally injection molded onto the surface of the first welding ring 411. In this case, the first plastic part 412 at least covers the side of the first welding ring 411 near the first cover plate body 101 and the circumferential side of the first welding ring 411. However, it is not limited to this. In other embodiments, the first plastic part 412 and the first welding ring 411 can be made into independent parts. When assembling the cover plate assembly, the first plastic part 412 and the first welding ring 411 are assembled and then installed onto the first pole post 301.

[0040] In some embodiments, the second support member 402 is an annular structure. This annular structure is sleeved outside the second column portion 321, fixedly connected to the second column portion 321 (e.g., welded), and fits against the outer surface of the second cover plate body 102. Thus, the second support member 402 can axially limit and position the second pole post 302, which helps ensure the connection stability between the second pole post 302, the second cover plate, and the second pole group. Specifically, the second support member 402 includes a second welding ring 421 and a second plastic part 422: the second welding ring 421 is a second conductive area and is sleeved outside the second column portion 321 and welded to it; at least a portion of the second plastic part 422 is located between the outer surface of the second cover plate body 102 and the side of the second welding ring 421 near the second cover plate body 102, so as to electrically isolate the second pole post 302 from the second cover plate body 102. To improve the connection stability between the second electrode post 302 and the second cover plate body 102, and to avoid problems such as tilting, offsetting, or shaking of the second electrode post 302 relative to the second cover plate body 102, the projection of the second welding ring 421 on the second cover plate body 102 can be at least partially located radially outside the second mounting hole 120, so that the second support member 402 and the outer surface of the second cover plate body 102 fit together. For example, when the second welding ring 421 is a ring and the second mounting hole 120 is a circular hole, the diameter of the second welding ring 421 is larger than the diameter of the second mounting hole 120. Thus, the second support member 402, composed of the second welding ring 421 and the second plastic part 422, can stably mount the second electrode post 302 on the outer surface of the second cover plate body 102.

[0041] In a specific implementation, the second plastic part 422 can be an annular insulating gasket placed between the second welding ring 421 and the second cover plate body 102, or the second plastic part 422 can be configured as a hollow structure sleeved on the outside of the second welding ring 421. For details, please refer to... Figure 1 ,as well as Figures 5 to 11In any of the accompanying drawings, the second plastic part 422 includes a second insulating end face 4221, a second limiting end face 4222, and a second cylindrical sidewall 4223. The second insulating end face 4221 is located on the side of the second welding ring 421 near the second cover plate body 102, that is, the second insulating end face 4221 is located between the second welding ring 421 and the second cover plate body 102. The second limiting end face 4222 is located on the side of the second welding ring 421 away from the second cover plate body 102. The inner diameter of the second limiting end face 4222 is less than or equal to the inner diameter of the second insulating end face 4221. It is used to cover the annular protrusion of the second welding ring 421 and expose the connecting end of the second welding ring 421 for welding with the first welding ring 411. The second cylindrical sidewall 4223 covers the circumferential sidewall of the second welding ring 421 and its two ends are respectively connected to the outer side of the second insulating end face 4221 and the outer side of the second limiting end face 4222. In a specific implementation, the second plastic part 422 and the second welding ring 421 can be integrally injection molded to form a second composite welding ring. That is, the second plastic part 422 is integrally injection molded onto the surface of the second welding ring 421. In this case, the second plastic part 422 at least covers the side of the second welding ring 421 near the second cover plate body 102 and the circumferential side of the second welding ring 421. However, it is not limited to this. In other embodiments, the second plastic part 422 and the second welding ring 421 can be made into independent parts. When assembling the cover plate assembly, the second plastic part 422 and the second welding ring 421 are assembled and then installed onto the second pole post 302.

[0042] In some embodiments, the first electrode post 301 and the first welding ring 411 can be fixedly connected by fillet welding, and the second electrode post 302 and the second welding ring 421 can also be fixedly connected by fillet welding. For details, please refer to... Figure 6 The end of the first pole post 301 near the second cover plate body 102 protrudes relative to the end face of the first welding ring 411 near the second cover plate body 102, and the first pole post 301 and the first welding ring 411 are fixed by fillet weld. The specific fillet weld position can be found in [reference needed]. Figure 6 The second welding position H2; and / or, the end of the second pole post 302 near the first cover plate body 101 protrudes relative to the end face of the second welding ring 421 near the first cover plate body 101, and the second pole post 302 and the second welding ring 421 are fixed by fillet weld, the specific fillet weld position of which can be found in [reference needed]. Figure 6 The third welding position H3 in the process.

[0043] In some embodiments, the first electrode post 301 and the second electrode post 302 are coaxially aligned but not directly welded; rather, they are coaxially fixed together through a first welding ring 411 and a second welding ring 421. For example, please refer to... Figure 7The first electrode post 301 and the first welding ring 411 are fixedly connected by seam welding, and the second electrode post 302 and the second welding ring 421 are also fixedly connected by seam welding. Specifically, the end of the first electrode post 301 near the second cover plate body 102 is flush with the end of the first welding ring 411 near the second cover plate body 102, and the first electrode post 301 and the first welding ring 411 are fixed by seam welding. The specific seam welding position can be found in [reference needed]. Figure 7 The fourth welding position H4; and / or, the end of the second pole post 302 near the first cover plate body 101 is flush with the end of the second welding ring 421 near the first cover plate body 101, and the second pole post 302 and the second welding ring 421 are welded together. The specific weld position can be found in [reference needed]. Figure 7 The fifth welding position H5. When the first welding ring 411 and the second welding ring 421 are coaxially aligned, the first pole post 301 and the second pole post 302 are also coaxially aligned. Then, welding is performed along the circumferential joint of the first welding ring 411 and the second welding ring 421. The specific location of the weld can be found in [reference needed]. Figure 7 The tenth welding position H10 shown in the figure achieves coaxial docking and electrical connection of the first pole post 301 and the second pole post 302 by coaxially welding the first welding ring 411 and the second welding ring 421. At this time, the first welding ring 411, the second welding ring 421, the first pole post 301 and the second pole post 302 constitute a pole post with an integral structure.

[0044] In some embodiments, the first pole post 301 and the first welding ring 411 are fixedly connected by seam welding, and the second pole post 302 and the second welding ring 421 are also fixedly connected by seam welding. Furthermore, the first pole post 301 and the second pole post 302 are coaxially aligned and welded together. For details, please refer to [link to relevant documentation]. Figure 8 The first pole post 301 has a first stepped groove along its circumference at one end near the second cover plate body 102. The radial groove surface of the first stepped groove is flush with the surface of the first welding ring 411 at one end near the second cover plate body 102 and is fixed by seam welding. The specific seam welding position can be found in [reference needed]. Figure 8 The sixth welding position H6; and / or, the second pole post 302 is provided with a second stepped groove along its circumference at one end near the first cover plate body 101, the radial groove surface of the second stepped groove is flush with the surface of the second welding ring 421 at one end near the first cover plate body 101 and is fixed by seam welding, the specific seam welding position can be found in Figure 8 The seventh welding position is H7. At this point, the axial groove surface of the first stepped groove is aligned with the axial groove surface of the second stepped groove and is fixed by seam welding along the circumferential direction. The welding position can be found in [reference needed]. Figure 8 The first welding position H1 is located in the middle, so that the second pole post 302 and the first pole post 301 are coaxially welded.

[0045] Furthermore, to avoid uneven weld surfaces between the first pole post 301 and the first welding ring 411, and between the second pole post 302 and the second welding ring 421, which could affect the connection effect, therefore, as Figure 9 As shown, in some embodiments, a first stepped enlarged hole is provided at one end of the through hole of the first welding ring 411 near the second cover plate body 102. The bottom surface of the first stepped enlarged hole is welded to the end face of the first pole post 301. The specific weld position can be found in [reference needed]. Figure 9 The eighth welding position H8 is shown in the image. Correspondingly, a second stepped enlarged hole is provided at one end of the through hole of the second welding ring 421 near the first cover plate body 101. The bottom surface of the second stepped enlarged hole is welded to the end face of the second pole post 302. The specific weld position can be found in [reference needed]. Figure 9 The ninth welding position H9 is shown in the diagram. Furthermore, the end of the first welding ring 411 near the second cover plate body 102 extends out of the first plastic part 412, and the end of the second welding ring 421 near the first cover plate body 101 extends out of the second plastic part 422. Thus, the first welding ring 411 and the second welding ring 421 extend out of the first plastic part 412 and the second plastic part 422 respectively, are coaxially aligned, and are fixed by circumferential welding. The specific welding positions can be found in [reference needed]. Figure 9 The tenth welding position H10.

[0046] Further, please see Figure 5 In some embodiments, the outer surface of the first cover plate body 101 is provided with a first recess 111, and the end of the first support member 401 near the first cover plate body 101 is adapted to the first recess 111; and / or, the outer surface of the second cover plate body 102 is provided with a second recess 121, and the end of the second support member 402 near the second cover plate body 102 is adapted to the second recess 121. Thus, the first support member 401 can be positioned by the first recess 111, and the second support member 402 can be positioned by the second recess 121. Moreover, the first recess 111 and / or the second recess 121 help to reduce the distance between the first cover plate body 101 and the second cover plate body 102.

[0047] In some embodiments, the cover plate assembly also includes a sealing structure. For example, a first sealing structure 501 is provided within the first mounting hole 110 of the first cover plate body 101. The first sealing structure 501 can be an annular sealing ring with a rectangular, circular, trapezoidal, or other shaped cross-section. In this case, the first sealing structure 501 is located between the inner wall of the first mounting hole 110 of the first cover plate body 101 and the first pole post 301, thereby electrically isolating the first cover plate body 101 and the first pole post 301 and forming a seal at the connection. Alternatively, in other embodiments, the first sealing structure 501 can be configured with other structural shapes. In this case, at least a portion of the first sealing structure 501 is located between the inner wall of the first mounting hole 110 and the first pole post 301, and another portion of the first sealing structure 501 is located on the inner side and / or the outer side of the first cover plate body 101. For example, the first sealing structure 501 includes a first insulating seal 511 and a second insulating seal 512: the cylindrical portion of the first insulating seal 511 is located between the inner wall of the first mounting hole 110 and the first pole post 301, and the annular outer edge of the first insulating seal 511 is located between the first limiting protrusion 312 of the first pole post 301 and the inner side surface of the first cover plate body 101; the cylindrical portion of the second insulating seal 512 is located between the inner wall of the first mounting hole 110 and the first pole post 301, and the annular outer edge of the second insulating seal 512 is in contact with the outer side surface of the first cover plate body 101, located between the outer side surface of the first cover plate body 101 and the first support member 401.

[0048] Correspondingly, the aforementioned cover plate assembly also includes a second sealing structure 502, at least a portion of which is located between the inner wall of the second mounting hole 120 and the second pole post 302. The second sealing structure 502 can be an annular sealing ring with a rectangular, circular, trapezoidal, or other shaped cross-section. In this case, the second sealing structure 502 is located between the inner wall of the second mounting hole 120 and the second pole post 302 of the second cover plate body 102, thereby electrically isolating the second cover plate body 102 and the second pole post 302 and forming a seal at the connection. Alternatively, in other embodiments, the second sealing structure 502 can be configured with other structural shapes, in which case at least a portion of the second sealing structure 502 is located between the inner wall of the second mounting hole 120 and the second pole post 302, and another portion of the second sealing structure 502 is located on the inner surface and / or the outer surface of the second cover plate body 102. For example, the second sealing structure 502 includes a third insulating seal 521 and a fourth insulating seal 522: the cylindrical portion of the third insulating seal 521 is located between the inner wall of the second mounting hole 120 and the second pole post 302, and the annular outer edge of the third insulating seal 521 is located between the second limiting protrusion 322 of the second pole post 302 and the inner side surface of the second cover plate body 102; the cylindrical portion of the fourth insulating seal 522 is located between the inner wall of the second mounting hole 120 and the second pole post 302, and the annular outer edge of the fourth insulating seal 522 is in contact with the outer side surface of the second cover plate body 102, and is located between the outer side surface of the second cover plate body 102 and the second support member 402.

[0049] In some embodiments, the first plastic layer 201 in the first cover plate is located on the side of the first cover plate body 101 away from the second cover plate body 102 (i.e., the inner side of the first cover plate body 101) and is fixedly connected to the first cover plate body 101. The first plastic layer 201 is provided with a third mounting hole 210. The first insulating seal 511 is provided with a first outer edge (i.e., the annular outer edge of the first insulating seal 511) protruding outward from one end near the first pole group. The first outer edge is located in the third mounting hole 210 and between the first limiting protrusion 312 of the first pole post 301 and the inner side of the first cover plate body 101, and is clearance-fitted with the third mounting hole 210. Similarly, the second plastic layer 202 in the second cover plate is located on the side of the second cover plate body 102 away from the first cover plate body 101 (i.e., the inner side of the second cover plate body 102) and is fixedly connected to the second cover plate body 102. The second plastic layer 202 is provided with a fourth mounting hole 220. The third insulating seal 521 is provided with a third outer edge (i.e., the annular outer edge of the third insulating seal 521) protruding outward from one end near the second pole group. The third outer edge is located in the fourth mounting hole 220 and between the second limiting protrusion 322 of the second pole post 302 and the inner side of the second cover plate body 102, and is clearance-fitted with the fourth mounting hole 220.

[0050] In specific implementation, in the first support member 401, the inner diameter of the first insulating end face 4121 of the first plastic part 412 is larger than the inner diameter of the first welding ring 411. Furthermore, the second insulating seal 512, near the end of the first support member 401, has a second outer edge (i.e., the annular outer edge of the second insulating seal 512) protruding outwards circumferentially. This second outer edge is located within the inner hole of the first insulating end face 4121 and is clearance-fitted with it. Similarly, in the second support member 402, the inner diameter of the second insulating end face 4221 of the second plastic part 422 is larger than the inner diameter of the second welding ring 421. Furthermore, the fourth insulating seal 522, near the end of the second support member 402, has a fourth outer edge (i.e., the annular outer edge of the fourth insulating seal 522) protruding outwards circumferentially. This fourth outer edge is located within the inner hole of the second insulating end face 4221 and is clearance-fitted with it.

[0051] In specific implementations, both the first cover plate body 101 and the second cover plate body 102 can be made of aluminum alloy panels or ceramic panels. Furthermore, the first sealing structure 501 can be made of insulating plastic; and / or, the second sealing structure 502 can be made of insulating plastic; and / or, the first welding ring 411 can be a ring-shaped component made of plastic, ceramic, or other insulating materials, or the first welding ring 411 can also be a ring-shaped component made of the same material as the first pole post 301. Preferably, the material of the first welding ring 411 is ceramic, which has insulating properties and is easy to weld, or the material is the same as the first pole post 301; and / or, the second welding ring 421 can be a ring-shaped component made of plastic, ceramic, or other insulating materials, or the second welding ring 421 can also be a ring-shaped component made of the same material as the second pole post 302. Preferably, the material of the second welding ring 421 is ceramic, which has insulating properties and is easy to weld, or the material is the same as the second pole post 302.

[0052] In some embodiments, the first electrode 301 is the positive electrode and the second electrode 302 is the negative electrode. In this case, the first electrode 301 is made of aluminum alloy, and the second electrode 302 is made of copper-aluminum composite. For details, please refer to... Figure 10 or Figure 11 The material of the first connecting portion 302a in the second pole post 302, used to connect to the first pole post 301, includes aluminum, and the material of the second connecting portion 302b in the second pole post 302, which is away from the first pole post 301 and used to connect to the second pole group, includes copper. In a specific implementation, a first groove 3010 for easy welding can be provided at the end of the first pole post 301 away from the second pole post 302. In this case, the end of the second pole post 302 away from the first pole post 301 may not have a groove (e.g., ...). Figure 10 As shown in the image), grooves can also be provided (such as...). Figure 11 (as shown in the image).

[0053] In some embodiments, the first electrode 301 is the negative electrode and the second electrode 302 is the positive electrode. In this case, the material of the first electrode 301 is pure copper, and the material of the second electrode 302 is a copper-aluminum composite electrode. For details, please refer to... Figure 10 or Figure 11 The material of the first connecting portion 302a in the second pole 302 used to connect to the first pole 301 includes copper, and the material of the second connecting portion 302b in the second pole 302, which is away from the first pole 301 and used to connect to the second pole group, includes aluminum. In a specific implementation, a first groove 3010 for easy welding can be provided at the end of the first pole 301 away from the second pole 302. In this case, the end of the second pole 302 away from the first pole 301 may not have a groove (e.g., ...). Figure 10 As shown in the image), grooves can also be provided (such as...). Figure 11 (As shown in the diagram). In addition, in other embodiments, other conductive materials can be used to make the first electrode 301 and the second electrode 302. The specific material can be as long as it meets the actual needs and requirements, such as at least meeting the requirements of high conductivity, oxidation resistance, weldability and electrochemical stability.

[0054] During battery production, since the first and second cells arranged adjacent to each other need to maintain electrical isolation, the preset distance 'a' between the outer side of the first cover plate body 101 and the outer side of the second cover plate body 102 needs to meet the requirements of electrical isolation.

[0055] In specific implementation, electrical isolation between the first cover plate body 101 and the second cover plate body 102 can be achieved through an air gap. That is, only a portion of the first electrode post 301 and a portion of the second electrode post 302 are exposed between the outer surfaces of the first cover plate body 101 and the second cover plate body 102 at the interval between the first mounting hole 110 and the second mounting hole 120. The other areas between the outer surfaces of the first cover plate body 101 and the second cover plate body 102 are basically air gaps. Specifically, when electrical isolation between the outer surfaces of the first cover plate body 101 and the second cover plate body 102 is achieved through an air gap, since the first electrode post 301 and the second electrode post 302 are directly welded, there is no need to install busbars or other connecting parts. Therefore, the preset distance 'a' between the outer surfaces of the first cover plate body 101 and the second cover plate body 102 is not affected by busbars or other connecting parts and can be minimized, which is beneficial for compressing the overall volume of the battery module and increasing the battery capacity.

[0056] Furthermore, in some preferred embodiments, the insulation performance between the first battery cell and the second battery cell can be improved by providing an insulating spacer between the outer side of the first cover plate body 101 and the outer side of the second cover plate body 102. For example, in some embodiments, the outer side of the first cover plate body 101 and the outer side of the second cover plate body 102 are respectively attached to or abut against the two sides of the insulating spacer. In this case, the thickness of the insulating spacer is equal to the preset distance between the outer side of the first cover plate body 101 and the outer side of the second cover plate body 102 in the direction perpendicular to the thickness of the cover plate (i.e., the direction perpendicular to the side of the cover plate body near the electrode group). In this case, the insulating spacer not only has insulation performance, but also provides a certain support for the first cover plate body 101 and the second cover plate body 102. However, this is not the only limitation. In other embodiments, the thickness of the insulating spacer can be less than the preset distance between the outer surfaces of the first cover plate body 101 and the second cover plate body 102, and only one of the outer surfaces of the first cover plate body 101 and the second cover plate body 102 is in contact with the insulating spacer. Alternatively, in other embodiments, the thickness of the insulating spacer can be less than the preset distance between the outer surfaces of the first cover plate body 101 and the second cover plate body 102, and neither the outer surfaces of the first cover plate body 101 nor the second cover plate body 102 are in contact with the insulating spacer. In this case, the insulating spacer only has insulating properties and is mainly used to achieve electrical isolation between the first cover plate body 101 and the second cover plate body 102. Alternatively, in some other embodiments, a portion of the outer surface of the first cover plate body 101 may be in contact with the insulating spacer, while another portion may maintain a greater than zero distance from the insulating spacer; and / or, a portion of the outer surface of the second cover plate body 102 may be in contact with the insulating spacer, while another portion may maintain a greater than zero distance from the insulating spacer.

[0057] In addition, in some embodiments, an insulating layer can be provided on the outer side of the first cover plate body 101 and / or the outer side of the second cover plate body 102 to further ensure the electrical isolation effect between the first cover plate body 101 and the second cover plate body 102.

[0058] In summary, by adding an insulating spacer between the first cover plate body 101 and the second cover plate body 102, and / or by providing an insulating layer on the outer surface of the cover plate, the electrical isolation effect between the first cover plate body 101 and the second cover plate body 102 can be further guaranteed. In specific implementations, technicians can select the location of the insulating spacer according to the actual situation, so that the insulating spacer can support the cover plate body that is in contact with the insulating spacer. In specific implementations, the insulating spacer located between the first cover plate body 101 and the second cover plate body 102 can be columnar, plate-like, mesh-like, or any other structural shape that can provide insulation and limiting functions. Furthermore, in specific implementations, in the cover plate thickness direction, the thickness of at least a portion of the insulating spacer can be equal to the preset distance between the outer surface of the first cover plate body 101 and the outer surface of the second cover plate body 102; and / or, the thickness of at least a portion of the insulating spacer can be less than the preset distance between the outer surface of the first cover plate body 101 and the outer surface of the second cover plate body 102.

[0059] In some embodiments, the outer side of the first cover plate body 101 and the outer side of the second cover plate body 102 are electrically isolated by an air gap. At this point, when the maximum working voltage (DC) between battery cells is ≤30V, the preset spacing a can be approximately 0.2mm, or even 0 < a ≤ 2mm; when the maximum working voltage (DC) between battery cells is ≤60V, the preset spacing a can be any value within the range of 1.0mm to 1.5mm; when the maximum working voltage (DC) between battery cells is ≤100V, the preset spacing a can be any value within the range of 1.5mm to 2.0mm; when the maximum working voltage (DC) between battery cells is ≤200V, the preset spacing a can be any value within the range of 2.5mm to 3.0mm; when the maximum working voltage (DC) between battery cells is ≤400V, the preset spacing a can be any value within the range of 3.0mm to 4.0mm; when the maximum working voltage (DC) between battery cells is ≤800V, the preset spacing a can be any value within the range of 5.0mm to 8.0mm.

[0060] In some embodiments, the outer side of the first cover plate body 101 and the outer side of the second cover plate body 102 are electrically isolated from each other by an insulating spacer and / or an insulating layer. Since the first terminal 301 and the second terminal 302 are directly welded together, there is no need to install connecting components such as busbars. Therefore, the arrangement of the insulating spacer and / or insulating layer between the outer side of the first cover plate body 101 and the outer side of the second cover plate body 102 is not affected by the busbar. Furthermore, the preset distance 'a' between the outer side of the first cover plate body 101 and the outer side of the second cover plate body 102 can be minimized. This preset distance 'a' is determined solely by the electrical isolation requirements, the structure of the battery cell itself, and the structure and thickness of the insulating spacer and / or insulating layer. This facilitates reducing the overall volume of the battery module and increasing the battery capacity. It should be noted that the insulating spacer mentioned in this application can be an insulating partition, the material of which can be any one or a combination of PET (polyester film), PI (polyimide), mica board, aramid paper, epoxy fiberglass board, aerogel composite film, and ceramicized silicone pad, and the thickness can be any value within the range of 0.1 mm to 0.5 mm, or the partition thickness can be greater than 0.5 mm according to actual needs. The insulating layer mentioned in this application refers to an insulating layer formed by coating an insulating material on the outer surface of the first cover plate body 101 and / or the outer surface of the second cover plate body 102, such as a PET film with a thickness of any value within the range of 0.3 mm to 0.35 mm, such as a PET film with a thickness of about 0.25 mm, such as a PI film with a thickness of any value within the range of 0.25 mm to 0.3 mm. In addition, in specific implementations, when electrical isolation is achieved between the outer surface of the first cover plate body 101 and the outer surface of the second cover plate body 102 by means of an insulating spacer and / or an insulating layer, an air gap of 1 mm to 2 mm can also be maintained to form double insulation. Alternatively, in other embodiments, the preset distance 'a' between the outer side of the first cover plate body 101 and the outer side of the second cover plate body 102 can be made larger according to actual needs.

[0061] Please see Figure 12 In specific implementation, the assembly method of the above-mentioned cover plate assembly may include the following steps: S1: Assemble to form the first cover plate unit The first plastic part 412 is installed on the first welding ring 411, or the first plastic part 412 is formed on the outer surface of the first welding ring 411 by integral injection molding, thereby obtaining the first support member 401. The first sealing structure 501, the first pole post 301, the first support member 401 and the first cover plate (including the first cover plate body 101 and the first plastic layer 201) are assembled and welded at the connection between the first pole post 301 and the first support member 401 to obtain the first cover plate unit. S2: Assemble to form the second cover plate unit The second plastic part 422 is installed on the second welding ring 421, or the second plastic part 422 is formed on the outer surface of the second welding ring 421 by integral injection molding, thereby obtaining the second support 402. The second sealing structure 502, the second pole post 302, the second support member 402 and the second cover plate (including the second cover plate body 102 and the second plastic layer 202) are assembled and welded at the connection between the second pole post 302 and the second support member 402 to obtain the second cover plate unit. S3: The first pole post 301 and the second pole post 302 are coaxially aligned and welded, or the first support member 401 and the second support member 402 are coaxially aligned and welded in the conductive area, thereby forming an integral pole post structure, ultimately obtaining... Figures 2 to 5 The welding positions of the cover plate assembly shown can be found in [reference needed]. Figures 6 to 11 .

[0062] This application embodiment also provides a battery module, which includes a first battery cell and a second battery cell. The first battery cell includes a first housing and a first electrode group located in the first housing. The second battery cell includes a second housing and a second electrode group located in the second housing. A cover plate assembly provided in any of the above embodiments is disposed between the first electrode group and the second electrode group. In the cover plate assembly, the first terminal post 301 and the second terminal post 302 are coaxially aligned and fixedly connected. Moreover, the end of the first terminal post 301 away from the second cover plate body 102 is electrically connected to the first electrode tab of the first electrode group, and the end of the second terminal post 302 away from the first cover plate body 101 is electrically connected to the second electrode tab of the second electrode group. The first terminal post 301 and the first electrode tab of the first electrode group can be directly welded, or bonded with conductive adhesive, or fixedly connected by a snap-fit ​​structure, or connected by a connector, or other arbitrary means to achieve electrical connection. Correspondingly, the second terminal post 302 and the second electrode tab of the second electrode group can be directly welded, or bonded with conductive adhesive, or fixedly connected by a snap-fit ​​structure, or connected by a connector, or other arbitrary means to achieve electrical connection.

[0063] Furthermore, the first housing of the first battery cell is welded to the first cover body 101 in the cover assembly to form a closed space through the first housing and the first cover body 101, thereby achieving the purpose of encapsulating the first electrode group and other internal battery components located in the first housing; correspondingly, the second housing of the second battery cell is welded to the second cover body 102 in the cover assembly to form a closed space through the second housing and the second cover body 102, thereby achieving the purpose of encapsulating the second electrode group and other internal battery components located in the second housing.

[0064] It should be noted that the first and second cells mentioned in this application can be two cells arranged adjacently in the same battery module, or the first and second cells can be two cells from two different battery modules arranged adjacently. When the first and second cells are two cells arranged adjacently in the same battery module, the cover plate assembly is used to realize the series / parallel connection between the two cells arranged adjacently in the same battery module; when the first and second cells are two cells from two different battery modules arranged adjacently, the cover plate assembly is used to realize the series / parallel connection between the two battery modules arranged adjacently.

[0065] In specific implementation, among the two pole groups connected by the cover plate assembly provided in this application, the first pole tab of the first pole group connected to the first pole post 301 and the second pole tab of the second pole group connected to the second pole post 302 are respectively positive and negative poles, or the first pole tab of the first pole group connected to the first pole post 301 and the second pole tab of the second pole group connected to the second pole post 302 are both positive poles, or the first pole tab of the first pole group connected to the first pole post 301 and the second pole tab of the second pole group connected to the second pole post 302 are both negative poles. Specifically, if the first tab connected to the first terminal 301 is the positive terminal of one electrode group and the second tab connected to the second terminal 302 is the negative terminal of another electrode group, the two cells connected through the cover plate assembly provided in this application are connected in series; if the first tab connected to the first terminal 301 is the negative terminal of one electrode group and the second tab connected to the second terminal 302 is the positive terminal of another electrode group, the two cells connected through the cover plate assembly provided in this application are connected in series; if the first tab connected to the first terminal 301 and the second tab connected to the second terminal 302 are the positive terminals of two electrode groups respectively, the two cells connected through the cover plate assembly provided in this application are connected in parallel; if the first tab connected to the first terminal 301 and the second tab connected to the second terminal 302 are the negative terminals of two electrode groups respectively, the two cells connected through the cover plate assembly provided in this application are connected in parallel.

[0066] It should be noted that the battery cell referred to in this application is the smallest battery unit capable of storing electrical energy and independently charging and discharging, mainly including electrode assembly, casing, electrolyte, and a cover plate located at one end of the casing. A battery module typically contains multiple battery cells.

[0067] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed.

[0068] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0069] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A cover plate assembly, characterized in that, The cover plate assembly, used for installation between the first electrode group of the first battery cell and the second electrode group of the second battery cell, includes: The first cover plate body is provided with a first mounting hole; The second cover plate body is provided with a second mounting hole; the outer side surface of the first cover plate body and the outer side surface of the second cover plate body are arranged opposite to each other and maintain a preset distance greater than zero; The first pole post is inserted into the first mounting hole and is insulated from the first cover plate body; The second pole post is inserted into the second mounting hole and is insulated from the second cover plate body; The first support member is located on the outer side of the first cover plate body and is electrically isolated from and axially limited thereto; the portion of the first pole post extending out of the first mounting hole is fitted into the through hole of the first support member and welded thereto; The second support member is located on the outer side of the second cover plate body and is electrically isolated from and axially limited thereto; the portion of the second pole post extending out of the second mounting hole is fitted into the through hole of the second support member and welded thereto; Wherein: the second pole post and the first pole post are coaxially welded, and / or, the first conductive area in the first support member and the second conductive area in the second support member are coaxially welded.

2. The cover plate assembly according to claim 1, characterized in that, The first pole post includes: The first column portion passes through the first mounting hole and is electrically isolated from the first cover plate body; The first limiting protrusion is arranged around the pole post in the circumferential direction and protrudes from the circumferential sidewall of the first post body. It is located outside the first mounting hole and is electrically isolated from the inner side of the first cover plate body and is axially limited. And / or, The second pole includes: The second column portion passes through the second mounting hole and is electrically isolated from the second cover plate body; The second limiting protrusion is arranged around the pole post in the circumferential direction and protrudes from the circumferential side wall of the second column body. It is located outside the second mounting hole and is electrically isolated from the inner side of the second cover plate body and is axially limited.

3. The cover plate assembly according to claim 1, characterized in that, The first support member includes a first welding ring and a first plastic part: the first welding ring is the first conductive area and is sleeved on the outside of the first pole and welded to it; the projection of the first welding ring on the first cover plate body is at least partially located on the radial outer side of the first mounting hole; at least part of the first plastic part is located between the outer side of the first cover plate body and the side of the first welding ring near the first cover plate body. And / or, the second support includes a second welding ring and a second plastic part: the second welding ring is the second conductive area and is sleeved on the outside of the second pole and welded to it; the projection of the second welding ring on the second cover plate body is at least partially located radially outside the second mounting hole; at least part of the second plastic part is located between the outer side of the second cover plate body and the side of the second welding ring near the second cover plate body.

4. The cover plate assembly according to claim 3, characterized in that, The end of the first pole near the second cover plate body protrudes relative to the end face of the first welding ring near the second cover plate body, and the first pole and the first welding ring are fixed by fillet welding; And / or, the end of the second pole near the first cover plate body protrudes relative to the end face of the second welding ring near the first cover plate body, and the second pole and the second welding ring are fixed by fillet welding.

5. The cover plate assembly according to claim 3, characterized in that, The end of the first pole near the second cover plate body is flush with the end of the first welding ring near the second cover plate body, and the first pole and the first welding ring are welded together. And / or, the end of the second pole near the first cover plate body is flush with the end of the second welding ring near the first cover plate body, and the second pole and the second welding ring are fixed by seam welding.

6. The cover plate assembly according to claim 3, characterized in that, The first pole post has a first stepped groove along its circumference at one end near the second cover plate body. The radial groove surface of the first stepped groove is flush with the surface of the first welding ring at one end near the second cover plate body and is fixed by seam welding. And / or, the second pole post is provided with a second stepped groove along its circumference at one end near the first cover plate body, and the radial groove surface of the second stepped groove is flush with the surface of the second welding ring at one end near the first cover plate body and is fixed by seam welding.

7. The cover plate assembly according to claim 3, characterized in that, The first welding ring has a first stepped enlarged hole at one end near the second cover plate body, and the bottom surface of the first stepped enlarged hole is welded to the end face of the first pole post. The second welding ring has a second stepped enlarged hole at one end near the first cover plate body, and the bottom surface of the second stepped enlarged hole is welded to the end face of the second pole post. The first welding ring and the second welding ring extend out of the first plastic part and the second plastic part respectively, are coaxially aligned and are fixed by seam welding.

8. The cover plate assembly according to claim 3, characterized in that: The first plastic part is integrally injection molded onto the surface of the first welding ring, and the first plastic part covers the side of the first welding ring near the first cover plate body and the circumferential side of the first welding ring. And / or, the second plastic part is integrally injection molded onto the surface of the second welding ring, and the second plastic part covers a portion of the side of the second welding ring near the body of the second cover plate and the circumferential side of the second welding ring.

9. The cover plate assembly according to any one of claims 1 to 8, characterized in that, The outer surfaces of the first cover plate body and the second cover plate body are electrically isolated by an air gap; And / or, the outer side of the first cover plate body and the outer side of the second cover plate body are electrically isolated by an insulating spacer; And / or, at least one of the outer surfaces of the first cover plate body and the second cover plate body is provided with an insulating layer.

10. A battery module, comprising a first battery cell and a second battery cell, wherein the first battery cell includes a first housing and a first electrode group located in the first housing, and the second battery cell includes a second housing and a second electrode group located in the second housing; Its features are, A cover plate assembly as described in any one of claims 1 to 9 is disposed between the first electrode group and the second electrode group; In the cover plate assembly, the end of the first pole away from the second cover plate body is electrically connected to the first tab of the first pole group, and the end of the second pole away from the first cover plate body is electrically connected to the second tab of the second pole group.

Images