Battery assembly method and battery

Abstract

The application belongs to the technical field of batteries, and discloses a battery assembling method and a battery. The method comprises the following steps: S1, installing a protective end plate on the first surface and / or the second surface of a pole group; S2, wrapping an insulating film outside the multiple side surfaces of the pole group, and hot melting the insulating film and the protective end plate to form a pole group unit; S3, installing the pole group unit into a cavity of a composite shell; S4, installing a composite cover plate at an opening of the composite shell; S5, welding the composite cover plate and the composite shell; S6, welding the composite pole and the composite cover plate and welding the composite pole and the composite shell; and S7, realizing current conduction between the composite pole and the tab. The current conduction is realized by connecting the tab and the composite pole at last, so that the influence of other welding processes on the connection quality of the tab and the composite pole is avoided. Since the tab realizes the conduction of current by extending out of the composite shell, the occupation of the internal space of the composite shell is reduced, and the space utilization is improved.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and in particular to a battery assembly method and a battery. Background Technology

[0002] The traditional assembly process for blade batteries typically involves first inserting the terminals into the battery casing, then welding the terminals to the corresponding polarity tabs, followed by sequentially installing the lower plastic and cover plate, with a portion of the terminals extending through the lower plastic and cover plate and protruding from the battery casing. After the cover plate is assembled, it is welded to the battery casing. Then, on the outer side of the cover plate corresponding to the protruding portion of the terminals, the upper plastic, sealing ring, and welding station are sequentially installed, and the welding station is welded to the cover plate and to the terminals protruding from the cover plate, thus completing the assembly of the blade battery.

[0003] However, the blade battery assembled using this method has several drawbacks. First, the tabs and terminals need to be welded together first, followed by the welding of the cover plate to the battery casing, the welding station to the cover plate, and the welding station to the terminals. This process exposes the already welded tabs and terminals to adverse factors such as high temperatures and vibrations during the welding of the cover plate to the battery casing, the welding station to the cover plate, and the welding station to the terminals, thus reducing the welding quality between the terminals and tabs and lowering the product yield. Second, because this method also requires the terminals and tabs to be connected inside the battery casing, the tabs and terminals occupy a large amount of space inside the battery casing, limiting the volume of the electrode assembly and resulting in lower energy density. Furthermore, since the tab side involves welding the cover plate to the battery casing, the welding station to the cover plate, the welding station to the terminals, and the tabs to the terminals, a large number of welding operations are concentrated on the tab side. This causes adverse changes in the microstructure of the tab material due to the high temperatures generated by the numerous welding operations, affecting the electrical and mechanical properties of the tab itself, increasing the tab's resistance, and reducing the discharge performance and cycle life of the blade battery. Summary of the Invention

[0004] The purpose of this invention is to provide a battery assembly method and a battery with high product yield and energy density.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] On the one hand, a battery assembly method is provided, wherein the battery assembled by the battery assembly method includes a composite casing, an electrode assembly, a composite cover plate, composite terminals, and a protective end plate;

[0007] The battery assembly method includes the following steps:

[0008] S1. The electrode assembly includes a first surface and a second surface with electrode tabs, and a plurality of side surfaces perpendicular to the first surface and the second surface. A first through structure is provided on the protective end plate. The protective end plate is installed on the first surface and / or the second surface of the electrode assembly, and the electrode tabs pass through the first through structure.

[0009] S2. Cover the outside of the electrode group with an insulating film, so that the insulating film covers the outside of the plurality of sides, and heat-melt the insulating film to the protective end plate to form an electrode group unit;

[0010] S3. The composite shell is a single-sided open structure with a cavity. A second through structure for the electrode tab to extend is provided on the wall opposite to the open side, and a first insulating layer for isolating the composite shell from the electrode tab is injection molded on the wall. The electrode assembly unit is installed into the cavity of the composite shell, and the electrode tab that passes through the first through structure passes through the second through structure.

[0011] S4. The composite cover plate has a third through structure for the electrode tab to extend out and a second insulating layer for isolating the composite cover plate from the electrode tab. The composite cover plate is placed at the opening of the composite shell, and the electrode tab that passes through the first through structure passes through the third through structure.

[0012] S5. Weld the composite cover plate to the composite outer shell;

[0013] S6. A first receiving groove is provided on the side of the composite shell away from the electrode group, and a second receiving groove is provided on the side of the composite cover plate away from the electrode group. The composite electrode post is installed into the first receiving groove and the second receiving groove, and the composite electrode post is welded to the composite cover plate and the composite shell.

[0014] S7. Enable current conduction between the composite electrode post and the electrode tab.

[0015] Optionally, step S2 may further include the following steps:

[0016] S21. The battery further includes at least one protective side plate, and at least one of the protective side plates is pre-heat-melted to a predetermined position on the insulating film;

[0017] S22. The insulating film is wrapped around a plurality of the sides of the electrode assembly, and at least one of the protective side plates covers one of the sides of the electrode assembly;

[0018] S23. The overlapping area between the insulating film and the protective end plate is heat-fused.

[0019] Optionally, step S21 may further include the following steps:

[0020] S211. A positioning hole is made at the designated position of the insulating film;

[0021] S212. The protective side plate is provided with a positioning structure that cooperates with the positioning hole. The protective side plate is located at a set position of the insulating film, and the positioning structure is aligned with the positioning hole.

[0022] S213. The assembled protective side plate and the insulating film are heat-fused together.

[0023] Optionally, step S23 further includes the following steps:

[0024] S231. The composite cover plate is pre-installed on the side of the protective end plate away from the electrode group, and the electrode lug that passes through the first through structure passes through the third through structure.

[0025] S232. Measure the distance L1 between the nearest point between the composite cover plate and the insulating film, and determine whether L1 satisfies 0.5mm≤L1≤3mm. If yes, proceed to step S233; otherwise, proceed to step S234.

[0026] S233. After removing the pre-installed composite cover plate, the overlapping area between the insulating film and the protective end plate is heat-fused to form the electrode unit.

[0027] S234. After removing the pre-installed composite cover plate, cut the insulating film. After the cutting is completed, proceed to step S231.

[0028] Optionally, a plurality of spaced hot-melt points are provided in the overlapping area between the insulating film and the protective end plate. The distance between the boundary of each hot-melt point on the side away from the electrode group and the boundary of the overlapping area on the side away from the electrode group is L2, and satisfies 0.5mm≤L2≤3mm.

[0029] And / or, the distance between the boundary of each of the hot melting points facing the electrode group and the boundary of the overlapping area facing the electrode group is L3, and satisfies 0.5mm≤L3≤3mm.

[0030] Optionally, step S5 further includes the following steps:

[0031] S51. The composite cover plate and the composite shell are pre-welded and positioned through multiple spaced first pre-welding points;

[0032] S52. Fully weld the composite cover plate to the composite outer shell.

[0033] Optionally, the composite housing includes a housing body and the first insulating layer;

[0034] The outer shell body includes a first wall and a plurality of second walls perpendicular to the first wall. The plurality of second walls are arranged around the periphery of the first wall to form a hollow shell structure with one side open. The first receiving groove is opened on the side of the first wall away from the pole group. A first insertion through hole is also opened on the first wall and disposed in the first receiving groove.

[0035] The first insulating layer is injection molded on the first wall surface and includes a first upper insulating portion, a first lower insulating portion, and a first plug-in portion. The first upper insulating portion is disposed on the side of the first wall surface away from the electrode assembly and located in the first receiving groove. The first lower insulating portion is disposed on the side of the first wall surface facing the electrode assembly. The first plug-in portion is inserted into the first plug-in through hole and is used to connect the first upper insulating portion and the first lower insulating portion. The second through structure penetrates the first upper insulating portion, the first plug-in portion, and the first lower insulating portion.

[0036] Optionally, the composite cover plate includes a cover plate body and a second insulating layer;

[0037] The second receiving groove is formed on the cover plate body, and the cover plate body is also provided with a second insertion through hole disposed in the second receiving groove;

[0038] The second insulating layer is injection molded onto the cover plate body and includes a second upper insulating portion, a second lower insulating portion, and a second insertion portion. The second upper insulating portion is located on the side of the cover plate body away from the electrode assembly and is situated within the second receiving groove. The second lower insulating portion is located on the side of the cover plate body facing the electrode assembly. The second insertion portion is inserted into the second insertion through hole and is used to connect the second upper insulating portion and the second lower insulating portion. The third through structure penetrates the second upper insulating portion, the second insertion portion, and the second lower insulating portion.

[0039] Optionally, step S6 further includes the following steps:

[0040] S61. The first upper insulating part is provided with a first mounting groove on the side away from the outer shell body, and the second upper insulating part is provided with a second mounting groove on the side away from the cover plate body. The battery also includes a connecting piece, which is inserted into the first mounting groove and the second mounting groove.

[0041] S62. Bend the portion of the electrode tab extending out of the second through structure and the third through structure, and weld the bent electrode tab to the connecting piece;

[0042] S63. The battery further includes a sealing ring, which is installed into the first receiving groove and the second receiving groove;

[0043] S64. The composite pole is installed into the first receiving groove and the second receiving groove;

[0044] S65. Weld the composite pole to the composite cover plate and the composite pole to the composite shell.

[0045] On the other hand, a battery is provided, which is assembled using the battery assembly method described in any of the preceding claims.

[0046] The beneficial effects of this invention are:

[0047] This invention provides a battery assembly method. First, a composite cover plate is welded to a composite shell. Then, a composite terminal is welded to both the composite shell and the composite cover plate. Finally, the tabs are connected to the composite terminal to achieve current conduction. This avoids the impact of other welding processes on the connection quality between the tabs and the composite terminal, which has already achieved current conduction. Furthermore, the tabs achieve current conduction with the composite terminal located outside the composite shell through a second and third through structure. This eliminates the space occupied by connecting the tabs to the composite terminal and the space occupied by the composite terminal extending into the composite shell. This reduces the internal space required, improving space utilization, and provides space for larger electrode groups, increasing energy density. Additionally, protective end plates with first through structures are provided on the first and / or second surfaces of the electrode group where the tabs are located, thus supporting and preventing the tabs from tilting and ensuring structural reliability. In addition, by adopting a single-sided open composite shell structure with a single composite cover plate, the electrode group extends through the second through structure of the composite shell to the side of the tab with less welding work, thereby reducing the impact of the high temperature generated by the welding work on the microstructure of the tab on that side, reducing the resistance of the tab on that side, and improving the overall discharge performance and cycle life of the battery.

[0048] The present invention also provides a battery that, by assembling it using the battery assembly method described above, allows the volume of the electrode assembly to be further increased, thereby improving the energy density of the battery and increasing its power supply capacity. Attached Figure Description

[0049] Figure 1 This is a flowchart of the battery assembly method provided by the present invention;

[0050] Figure 2 This is an exploded view of the battery structure provided by the present invention;

[0051] Figure 3This is a partial structural cross-sectional view of the first wall surface of the composite casing in the battery provided by the present invention;

[0052] Figure 4 This is a partial structural cross-sectional view of the composite cover plate in the battery provided by the present invention;

[0053] Figure 5 This is a schematic diagram of the thermal fusion structure of the insulating film and the protective side plate in the battery provided by the present invention;

[0054] Figure 6 This is a schematic diagram showing the distribution of the heat-melting points of the protective end plate and the insulating film at the composite cover plate in the battery provided by the present invention;

[0055] Figure 7 yes Figure 6 Enlarged view of the structure of section A;

[0056] Figure 8 This is a schematic diagram showing the distribution of pre-welded points of the composite cover plate and composite shell in the battery provided by the present invention;

[0057] Figure 9 This is a schematic diagram of the structure of the outer casing of the battery provided by the present invention;

[0058] Figure 10 This is a schematic diagram of the structure of the first insulating layer in the battery provided by the present invention;

[0059] Figure 11 This is a schematic diagram of the battery cover body structure provided by the present invention;

[0060] Figure 12 This is a schematic diagram of the structure of the second insulating layer in the battery provided by the present invention;

[0061] Figure 13 This is a schematic diagram of the structure of the protective end plate in the battery provided by the present invention.

[0062] In the picture:

[0063] 100. First pre-welding point;

[0064] 1. Composite shell; 11. Shell body; 111. First wall surface; 112. Second wall surface; 113. First receiving groove; 114. First insertion through hole; 12. First insulating layer; 121. First upper insulating part; 122. First lower insulating part; 123. First insertion part; 124. Second through structure; 125. First mounting groove;

[0065] 2. Pole group; 21. Pole tab; 22. First surface; 23. Second surface; 24. Side surface;

[0066] 3. Composite cover plate; 31. Cover plate body; 311. Second receiving groove; 312. Second insertion through hole; 32. Second insulating layer; 321. Second upper insulating part; 322. Second lower insulating part; 323. Second insertion part; 324. Third through structure; 325. Second mounting groove;

[0067] 4. Composite pole; 41. Pole body; 42. Welding ring; 43. Third insulation layer;

[0068] 5. Protective end plate; 51. First through-hole structure; 52. Shaping structure;

[0069] 6. Insulating film; 61. Positioning holes; 62. Hot melting point;

[0070] 7. Protective side panels;

[0071] 8. Connecting piece; 81. Connecting boss;

[0072] 9. Sealing ring. Detailed Implementation

[0073] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0074] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0075] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0076] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0077] In order to avoid the connection quality between the terminal and the tab being affected by the pre-connection of the terminal and the tab in subsequent processes, reduce the impact of the high temperature generated by a large number of welding operations on the microstructure of the tab, and reduce additional space occupation, improve space utilization and energy density, this embodiment provides a battery assembly method. The battery assembled by this battery assembly method includes a composite shell 1, a pole group 2, a composite cover plate 3, a composite terminal 4 and a protective end plate 5.

[0078] like Figures 1 to 13 As shown, the battery assembly method includes the following steps:

[0079] S1. The pole group 2 includes a first surface 22 and a second surface 23 with pole tabs 21, and a plurality of side surfaces 24 perpendicular to the first surface 22 and the second surface 23. A first through structure 51 is provided on the protective end plate 5. The protective end plate 5 is installed on the first surface 22 and / or the second surface 23 of the pole group 2, and the pole tabs 21 pass through the first through structure 51.

[0080] S2. An insulating film 6 is wrapped around the outside of the pole group 2, so that the insulating film 6 covers the outside of multiple sides 24, and the insulating film 6 is thermally fused with the protective end plate 5 to form a pole group unit.

[0081] S3. The composite shell 1 is a single-sided open structure with a cavity. A second through structure 124 for the tab 21 to extend is provided on the wall opposite to the open side, and a first insulating layer 12 for isolating the composite shell 1 and the tab 21 is injection molded on the wall. The pole assembly unit is installed into the cavity of the composite shell 1, and the tab 21 passing through the first through structure 51 passes through the second through structure 124.

[0082] S4. The composite cover plate 3 has a third through structure 324 for the tab 21 to extend out and a second insulating layer 32 for isolating the composite cover plate 3 from the tab 21. The composite cover plate 3 is placed at the opening of the composite shell 1, and the tab 21 that passes through the first through structure 51 passes through the third through structure 324.

[0083] S5. Weld the composite cover plate 3 to the composite shell 1;

[0084] S6. A first receiving groove 113 is provided on the side of the composite shell 1 away from the electrode group 2, and a second receiving groove 311 is provided on the side of the composite cover plate 3 away from the electrode group 2. The composite electrode post 4 is installed into the first receiving groove 113 and the second receiving groove 311, and the composite electrode post 4 is welded to the composite cover plate 3 and the composite electrode post 4 to the composite shell 1.

[0085] S7 enables current conduction between the composite pole 4 and the tab 21.

[0086] This battery assembly method involves first welding the composite cover plate 3 to the composite shell 1, then welding the composite terminal 4 to both the composite shell 1 and the composite cover plate 3, and finally connecting the tab 21 to the composite terminal 4 to conduct current. This avoids the impact of other welding processes on the connection quality between the tab 21 and the composite terminal 4, which have already achieved current conduction. Furthermore, the tab 21 connects to the composite terminal 4 located outside the composite shell 1 via the second through structure 124 and the third through structure 324, eliminating the need for connecting the tab 21 to the composite terminal 4 and for the composite terminal 4 to extend into the composite shell 1. This reduces the space occupied by the tab 21 and the composite terminal 4, improving space utilization, and provides space for increasing the size of the electrode assembly 2, thus increasing energy density. Additionally, the electrode assembly 2 has a protective end plate 5 with a first through structure 51 on its first surface 22 and / or second surface 23, which provides support and prevents the tab 21 from tilting, ensuring the reliability of the structure. In addition, by adopting a single-sided open composite shell 1 and a single composite cover plate 3, the electrode group 2 extends through the second through structure 124 of the composite shell 1, resulting in less welding work on the side of the electrode tab 21. This reduces the impact of the high temperature generated by the welding work on the microstructure of the electrode tab 21 on that side, reduces the resistance of the electrode tab 21 on that side, and improves the overall discharge performance and cycle life of the battery.

[0087] In this embodiment, the first surface 22 and the second surface 23 of the electrode group 2 are both equipped with protective end plates 5. When assembling the protective end plates 5 on both sides of the electrode group 2 and when heat-melting the protective end plates 5 and the insulating film 6 on both sides, the two protective end plates 5 can be assembled and heat-melted at the same time, or one side of the protective end plate 5 can be assembled and heat-melted separately first, and then the other side of the protective end plate 5 can be assembled and heat-melted. The assembly method can be freely selected according to the actual site conditions.

[0088] Optionally, such as Figure 2 , Figure 5 As shown, step S2 further includes the following steps:

[0089] S21, the battery also includes at least one protective side plate 7, which is pre-heat-melted into the insulating film 6 at a predetermined position;

[0090] S22. The insulating film 6 is wrapped around multiple sides 24 of the electrode group 2, and at least one protective side plate 7 is covered on one side 24 of the electrode group 2.

[0091] S23. Heat-melt the overlapping area between the insulating film 6 and the protective end plate 5.

[0092] By heat-melting the protective side plate 7 on the insulating film 6 before covering it, the protective side plate 7 can cover the side 24 of the electrode group 2 when the insulating film 6 is covered on the electrode group 2. This protects the side 24 of the electrode group 2 when it is put into the housing, thus preventing scratches during the housing process.

[0093] The number of protective side plates 7 can be freely set according to the protection requirements. In this embodiment, four protective side plates 7 are provided, which correspond one-to-one with the four sides 24 of the electrode group 2, thereby improving the protection performance of the electrode group 2.

[0094] Optionally, such as Figure 2 , Figure 5 As shown, step S21 further includes the following steps:

[0095] S211. A positioning hole 61 is made at a predetermined position on the insulating film 6;

[0096] S212, The protective side plate 7 is provided with a positioning structure that cooperates with the positioning hole 61. The protective side plate 7 is located at the set position of the insulating film 6, and the positioning structure is aligned with the positioning hole 61.

[0097] S213. The assembled protective side plate 7 and insulating film 6 are heat-fused together.

[0098] By opening a positioning hole 61 at a set position on the insulating film 6 and setting a positioning structure on the protective side plate 7 that cooperates with the positioning hole 61, the accuracy of the hot-melt position of the protective side plate 7 is ensured, thereby avoiding the inability to provide effective protection when the insulating film 6 covers the electrode group 2 due to the inaccurate position of the protective side plate 7 after hot melting.

[0099] Optionally, such as Figure 2 , Figure 6 , Figure 7 As shown, step S23 further includes the following steps:

[0100] S231. The composite cover plate 3 is pre-installed on the side of the protective end plate 5 away from the electrode group 2, and the electrode lug 21 passing through the first through structure 51 passes through the third through structure 324.

[0101] S232. Measure the distance L1 between the nearest point between the composite cover plate 3 and the insulating film 6, and determine whether L1 satisfies 0.5mm≤L1≤3mm. If yes, proceed to step S233; otherwise, proceed to step S234.

[0102] S233. After removing the pre-installed composite cover plate 3, the overlapping area between the insulating film 6 and the protective end plate 5 is heat-fused to form an electrode unit.

[0103] S234. After removing the pre-installed composite cover plate 3, cut the insulating film 6. After the cutting is completed, proceed to step S231.

[0104] By pre-installing the composite cover plate 3 and ensuring that the distance L1 between the composite cover plate 3 and the insulating film 6 is within the range of 0.5mm≤L1≤3mm, we can avoid the following problems: Firstly, the distance L1 between the composite cover plate 3 and the insulating film 6 is too small, which would affect the welding of the composite cover plate 3 and the composite shell 1 and easily cause welding explosions. Secondly, we can avoid the distance L1 between the composite cover plate 3 and the insulating film 6 being too large, which would increase the height of the protective end plate 5 and increase manufacturing costs.

[0105] In this embodiment, the spacing L1 between the cut insulating film 6 and the composite cover plate 3 after assembly can be any value between 0.5mm and 3mm or any range between two values, such as 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, etc.

[0106] Optionally, such as Figure 2 , Figure 6 , Figure 7 As shown, multiple spaced hot melt points 62 are provided in the overlapping area between the insulating film 6 and the protective end plate 5. The distance between the boundary of each hot melt point 62 on the side away from the electrode group 2 and the boundary of the overlapping area on the side away from the electrode group 2 is L2, and satisfies 0.5mm≤L2≤3mm.

[0107] By employing multiple spaced hot-melt points 62, the heat fusion between the insulating film 6 and the protective end plate 5 is achieved. This ensures a sufficiently wide range for the heat fusion, guaranteeing a strong bond. Furthermore, compared to full heat fusion, the fusion area is smaller, thus shortening the time required for the heat fusion operation and improving efficiency. Simultaneously, by setting L2 as the distance between the boundary of each hot-melt point 62 on the side away from the electrode group 2 and the boundary of the overlapping area on the side away from the electrode group 2, and limiting L2 to satisfy 0.5mm ≤ L2 ≤ 3mm, a suitable distance is maintained between the hot-melt points 62 and the boundary of the overlapping area on the side away from the electrode group 2. This avoids insufficient operable area during heat fusion due to too small a distance, and also avoids loose connection of the area on the side of the hot-melt points 62 away from the electrode group 2 due to too large a distance.

[0108] The distance L2 between the boundary of each hot melting point 62 on the side away from the electrode group 2 and the boundary of the overlapping area on the side facing the composite cover plate 3 can be any value between 0.5mm and 3mm or any range between two values, such as 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, etc.

[0109] Optionally, such as Figure 2 , Figure 6 , Figure 7 As shown, the distance between the boundary of each hot melting point 62 facing the electrode group 2 and the boundary of the overlapping area facing the electrode group 2 is L3, and satisfies 0.5mm≤L3≤3mm.

[0110] By employing multiple spaced hot-melt points 62, the heat fusion between the insulating film 6 and the protective end plate 5 is achieved. This ensures a sufficiently wide range for the heat fusion, guaranteeing a strong bond, and compared to full heat fusion, it results in a shorter operation time and higher efficiency. Simultaneously, by setting L3 as the distance between the boundary of each hot-melt point 62 facing the electrode group 2 and the boundary of the overlapping area facing the electrode group 2, and limiting L3 to satisfy 0.5mm ≤ L3 ≤ 3mm, a suitable distance is maintained between the hot-melt points 62 and the boundary of the overlapping area facing the electrode group 2. This avoids both insufficient space for heat fusion due to too small a distance and loose connection of the area facing the electrode group 2 due to too large a distance.

[0111] The distance L3 between the boundary of each hot melting point 62 facing the electrode group 2 and the boundary of the overlapping area away from the composite cover plate 3 can be any value between 0.5mm and 3mm or any range between two values, such as 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, etc.

[0112] Optionally, such as Figure 2 , Figure 8 As shown, step S5 also includes the following steps:

[0113] S51, the composite cover plate 3 and the composite shell 1 are pre-welded and positioned through multiple spaced first pre-welding points 100;

[0114] S52. Fully weld the composite cover plate 3 to the composite outer shell 1.

[0115] By first pre-welding the composite cover plate 3 and the composite shell 1 using multiple spaced first pre-welding points 100, the relative position between the composite cover plate 3 and the composite shell 1 is positioned before full welding. Even if the initial positioning is incorrect, it is easy to separate and reposition the two, realize recycling, and reduce the scrap rate of the product.

[0116] Optionally, such as Figure 2 , Figure 3 , Figure 9 , Figure 10 As shown, the composite housing 1 includes a housing body 11 and a first insulating layer 12;

[0117] The outer shell body 11 includes a first wall surface 111 and a plurality of second walls surface 112 perpendicular to the first wall surface 111. The plurality of second walls surface 112 are arranged around the periphery of the first wall surface 111 to form a hollow shell structure with one side open. A first receiving groove 113 is opened on the side of the first wall surface 111 away from the pole group 2. A first insertion through hole 114 is also opened on the first wall surface 111 and disposed in the first receiving groove 113.

[0118] The first insulating layer 12 is injection molded on the first wall surface 111 and includes a first upper insulating part 121, a first lower insulating part 122 and a first plug-in part 123. The first upper insulating part 121 is located on the side of the first wall surface 111 away from the pole group 2 and is located in the first receiving groove 113. The first lower insulating part 122 is located on the side of the first wall surface 111 facing the pole group 2. The first plug-in part 123 is inserted into the first plug-in through hole 114 and is used to connect the first upper insulating part 121 and the first lower insulating part 122. The second through structure 124 penetrates the first upper insulating part 121, the first plug-in part 123 and the first lower insulating part 122.

[0119] By setting a first insulating layer 12 consisting of a first upper insulating part 121, a first lower insulating part 122, and a first plug-in part 123, and by placing the first upper insulating part 121 on the side of the first wall surface 111 of the outer casing 11 away from the pole group 2, placing the first lower insulating part 122 on the side of the first wall surface 111 of the outer casing 11 facing the pole group 2, inserting the first plug-in part 123 into the first plug-in through hole 114, and allowing the second through structure 124 to penetrate the first upper insulating part 121, the first plug-in part 123, and the first lower insulating part 122, the first insulating layer 12 provides insulation protection for both sides of the first wall surface 111 of the outer casing 11 and the inside of the first plug-in through hole 114, thereby isolating the tab 21 from the first wall surface 111 of the outer casing 11 when the tab 21 passes through the first wall surface 111 of the outer casing 11, thus preventing direct contact between the tab 21 and the first wall surface 111 of the outer casing 11 and causing a short circuit, ensuring safety and protection.

[0120] Optionally, such as Figure 2 , Figure 3 , Figure 11 , Figure 12 As shown, the composite cover plate 3 includes a cover plate body 31 and a second insulating layer 32;

[0121] The second receiving groove 311 is provided on the cover plate body 31, and the cover plate body 31 is also provided with a second insertion through hole 312 provided in the second receiving groove 311.

[0122] The second insulating layer 32 is injection molded onto the cover plate body 31 and includes a second upper insulating part 321, a second lower insulating part 322, and a second insertion part 323. The second upper insulating part 321 is located on the side of the cover plate body 31 away from the electrode group 2 and is located in the second receiving groove 311. The second lower insulating part 322 is located on the side of the cover plate body 31 facing the electrode group 2. The second insertion part 323 is inserted into the second insertion through hole 312 and is used to connect the second upper insulating part 321 and the second lower insulating part 322. The third through structure 324 penetrates the second upper insulating part 321, the second insertion part 323, and the second lower insulating part 322.

[0123] By setting a second insulating layer 32 consisting of a second upper insulating part 321, a second lower insulating part 322, and a second insertion part 323, and placing the second upper insulating part 321 on the side of the cover plate body 31 away from the electrode group 2, placing the second lower insulating part 322 on the side of the cover plate body 31 facing the electrode group 2, inserting the second insertion part 323 into the second insertion through hole 312, and allowing the third through structure 324 to penetrate the second upper insulating part 321, the second insertion part 323, and the second lower insulating part 322, the second insulating layer 32 provides insulation protection for both sides of the cover plate body 31 and the inside of the second insertion through hole 312, isolating the electrode tab 21 from the cover plate body 31, preventing the electrode tab 21 from directly contacting the cover plate body 31 when passing through it, thus avoiding a short circuit and ensuring safety and protection.

[0124] In this embodiment, to verify the impact of distance dimensions L1, L2, and L3 on the quality of the assembled product in the battery assembly method, as shown in Table 1, six sets of embodiments and six sets of comparative examples are provided for verification. In the composite cover plate 3, the cover plate body 31 is actually welded to the outer shell body 11. Therefore, the distance dimension L1 between the closest point between the composite cover plate 3 and the insulating film 6 is essentially the distance between the cover plate body 31 and the insulating film 6 on the side of the boundary away from the electrode group 2.

[0125] Table 1

[0126]

[0127] In Example 1, the distance L1 between the composite cover plate 3 and the insulating film 6 is set to 0.5 mm, the distance L2 between the boundary of the hot melt point 62 away from the electrode group 2 and the boundary of the overlapping area away from the electrode group 2 is set to 0.5 mm, and the distance L3 between the boundary of the hot melt point 62 facing the electrode group 2 and the boundary of the overlapping area facing the electrode group 2 is set to 0.5 mm. After the battery is assembled according to the above data, it is verified that no explosion points appear around the weld of the cover. After the battery is disassembled, the insulating film 6 is not damaged and does not fall off.

[0128] In Example 2, the distance L1 between the composite cover plate 3 and the insulating film 6 is set to 1 mm, the distance L2 between the boundary of the hot melt point 62 away from the electrode group 2 and the boundary of the overlapping area away from the electrode group 2 is set to 2 mm, and the distance L3 between the boundary of the hot melt point 62 facing the electrode group 2 and the boundary of the overlapping area facing the electrode group 2 is set to 2 mm. After the battery is assembled according to the above data, it is verified that no explosion points appear around the weld of the cover. After the battery is disassembled, the insulating film 6 is not damaged and does not fall off.

[0129] In Example 3, the distance L1 between the composite cover plate 3 and the insulating film 6 is set to 1.5 mm, the distance L2 between the boundary of the hot melt point 62 away from the electrode group 2 and the boundary of the overlapping area away from the electrode group 2 is set to 1 mm, and the distance L3 between the boundary of the hot melt point 62 facing the electrode group 2 and the boundary of the overlapping area facing the electrode group 2 is set to 3 mm. After the battery is assembled according to the above data, it is verified that no explosion points appear around the weld of the cover. After the battery is disassembled, the insulating film 6 is not damaged and does not fall off.

[0130] In Example 4, the distance L1 between the composite cover plate 3 and the insulating film 6 is set to 2mm, the distance L2 between the boundary of the hot melt point 62 away from the electrode group 2 and the boundary of the overlapping area away from the electrode group 2 is set to 3mm, and the distance L3 between the boundary of the hot melt point 62 facing the electrode group 2 and the boundary of the overlapping area facing the electrode group 2 is set to 1mm. After the battery is assembled according to the above data, it is verified that no explosion points appear around the weld of the cover. After the battery is disassembled, the insulating film 6 is not damaged and does not fall off.

[0131] In Example 5, the distance L1 between the composite cover plate 3 and the insulating film 6 is set to 2.5 mm, the distance L2 between the boundary of the hot melting point 62 away from the electrode group 2 and the boundary of the overlapping area away from the electrode group 2 is set to 1.5 mm, and the distance L3 between the boundary of the hot melting point 62 facing the electrode group 2 and the boundary of the overlapping area facing the electrode group 2 is set to 2.5 mm. After the battery is assembled according to the above data, it is verified that no explosion points appear around the weld of the cover. After the battery is disassembled, the insulating film 6 is not damaged and does not fall off.

[0132] In Example 6, the distance L1 between the composite cover plate 3 and the insulating film 6 is set to 3mm, the distance L2 between the boundary of the hot melt point 62 away from the electrode group 2 and the boundary of the overlapping area away from the electrode group 2 is set to 2.5mm, and the distance L3 between the boundary of the hot melt point 62 facing the electrode group 2 and the boundary of the overlapping area facing the electrode group 2 is set to 1.5mm. After the battery is assembled according to the above data, it is verified that no explosion points appear around the weld of the cover. After the battery is disassembled, the insulating film 6 is not damaged and does not fall off.

[0133] As can be seen from Examples 1 to 6, when the distance L1 between the composite cover plate 3 and the insulating film 6 is within the range of 0.5mm≤L1≤3mm, the distance L2 between the boundary of the hot melting point 62 away from the electrode group 2 and the boundary of the overlapping area away from the electrode group 2 is within the range of 0.5mm≤L2≤3mm, and the distance L3 between the boundary of the hot melting point 62 towards the electrode group 2 and the boundary of the overlapping area towards the electrode group 2 is within the range of 0.5mm≤L3≤3mm, the battery assembled by this battery assembly method has no explosion points around the perimeter of the cover weld, and after disassembling the battery, the insulating film 6 is not damaged or falls off, indicating high product quality.

[0134] In Comparative Example 1, the distance L1 between the composite cover plate 3 and the insulating film 6 was set to 0.1 mm, the distance L2 between the boundary of the hot melting point 62 away from the electrode group 2 and the boundary of the overlapping area away from the electrode group 2 was set to 1 mm, and the distance L3 between the boundary of the hot melting point 62 facing the electrode group 2 and the boundary of the overlapping area facing the electrode group 2 was set to 1 mm. After the battery was assembled according to the above data, it was verified that a burst occurred when welding around the cover, and the insulating film 6 melted.

[0135] As can be seen from Comparative Example 1, when the distance L1 between the composite cover plate 3 and the insulating film 6 is less than the minimum value of 0.5mm≤L1≤3mm, the insulating film 6 is too close to the cover plate body 31, which causes blasting points to occur when welding the periphery of the cover. Furthermore, because the insulating film 6 is too close to the welding position, the high temperature generated during welding causes the insulating film 6 to melt, resulting in poor insulation protection performance of the assembled battery.

[0136] In Comparative Example 2, the distance L1 between the composite cover plate 3 and the insulating film 6 was set to 1 mm. The distance L2 between the boundary of the hot melt point 62 away from the electrode group 2 and the boundary of the overlapping area away from the electrode group 2 was set to 0.1 mm. The distance L3 between the boundary of the hot melt point 62 facing the electrode group 2 and the boundary of the overlapping area facing the electrode group 2 was set to 1 mm. After the battery was assembled according to the above data, it was found that the insulating film 6 detached. As can be seen from Comparative Example 2, when the distance L2 between the boundary of the hot melt point 62 away from the electrode group 2 and the boundary of the overlapping area away from the electrode group 2 is less than the minimum value of 0.5 mm ≤ L2 ≤ 3 mm, the hot melt point 62 is too close to the upper edge of the overlapping area with the protective end plate 5. This causes some of the hot melt point to extend beyond the upper edge of the insulating film 6, resulting in insufficient hot melt area between the insulating film 6 and the protective end plate 5. This leads to the problem of the insulating film 6 detaching, resulting in poor insulation protection performance of the assembled battery.

[0137] In Comparative Example 3, the distance L1 between the composite cover plate 3 and the insulating film 6 was set to 1 mm. The distance L2 between the boundary of the hot melt point 62 facing away from the electrode group 2 and the boundary of the overlapping area facing away from the electrode group 2 was set to 1 mm. The distance L3 between the boundary of the hot melt point 62 facing the electrode group 2 and the boundary of the overlapping area facing the electrode group 2 was set to 0.1 mm. After the battery was assembled according to the above data, it was found that the insulating film 6 and the protective end plate 5 underwent a melt-through phenomenon, resulting in a short circuit. As can be seen from Comparative Example 3, when the distance L3 between the boundary of the hot melt point 62 facing the electrode group 2 and the boundary of the overlapping area facing the electrode group 2 is less than the minimum value of 0.5 mm ≤ L3 ≤ 3 mm, the hot melt point 62 is too close to the lower edge of the overlapping area of ​​the protective end plate 5. This causes part of the hot melt point 62 to extend beyond the lower edge of the protective end plate 5, resulting in a melt-through phenomenon between the insulating film 6 and the protective end plate 5, thus causing a short circuit and resulting in poor insulation protection performance of the assembled battery.

[0138] In Comparative Example 4, the distance L1 between the composite cover plate 3 and the insulating film 6 was set to 4 mm. The distance L2 between the boundary of the hot melt point 62 facing away from the electrode group 2 and the boundary of the overlapping area facing away from the electrode group 2 was set to 1 mm. The distance L3 between the boundary of the hot melt point 62 facing the electrode group 2 and the boundary of the overlapping area facing the electrode group 2 was set to 1 mm. After assembly according to these data, the second insulating layer 32 occupied a large internal space, resulting in the compression of the electrode group 2 and thus a lower energy density of the assembled battery. Comparative Example 4 shows that when the distance L1 between the composite cover plate 3 and the insulating film 6 is greater than the maximum value of 0.5 mm ≤ L1 ≤ 3 mm, the insulating film 6 is far from the cover plate body 31, causing the second insulating layer 32 to occupy a large internal space. Therefore, to complete the assembly, the volume of the electrode group 2 needs to be reduced, thus lowering the energy density of the assembled battery, resulting in poor power supply capability and failing to meet usage requirements.

[0139] In Comparative Example 5, the distance L1 between the composite cover plate 3 and the insulating film 6 was set to 1 mm, the distance L2 between the boundary of the hot melt point 62 away from the electrode group 2 and the boundary of the overlapping area away from the electrode group 2 was set to 4 mm, and the distance L3 between the boundary of the hot melt point 62 facing the electrode group 2 and the boundary of the overlapping area facing the electrode group 2 was set to 1 mm. After the battery was assembled according to the above data, it was found that the insulating film 6 was located in the area between the hot melt point 62 and the upper edge of the overlapping area of ​​the protective end plate 5, and was not tightly connected to the protective end plate 5, which caused the insulating film 6 to be flipped. As can be seen from Comparative Example 5, when the distance L2 between the boundary of the hot melt point 62 on the side away from the electrode group 2 and the boundary of the overlapping area on the side away from the electrode group 2 is greater than the maximum value of 0.5mm≤L2≤3mm, the distance between the hot melt point 62 and the upper edge of the overlapping area with the protective end plate 5 is relatively far. As a result, the insulating film 6 is located in the area between the hot melt point 62 and the upper edge of the overlapping area with the protective end plate 5, and is not tightly connected to the protective end plate 5. This causes the insulating film 6 to have an edge flipped up, which does not meet the usage requirements.

[0140] In Comparative Example 6, the distance L1 between the composite cover plate 3 and the insulating film 6 is set to 1 mm, the distance L2 between the boundary of the hot melt point 62 away from the electrode group 2 and the boundary of the overlapping area away from the electrode group 2 is set to 1 mm, and the distance L3 between the boundary of the hot melt point 62 facing the electrode group 2 and the boundary of the overlapping area facing the electrode group 2 is set to 4 mm. After the battery is assembled according to the above data, it is verified that the insulating film 6 is located in the area between the hot melt point 62 and the lower edge of the overlapping area of ​​the protective end plate 5, and is not tightly connected to the protective end plate 5. There is a gap between the insulating film 6 and the electrode group 2. As can be seen from Comparative Example 6, when the distance L3 between the boundary of the hot melt point 62 facing the electrode group 2 and the boundary of the overlapping area facing the electrode group 2 is greater than the maximum value of 0.5mm≤L3≤3mm, the distance between the hot melt point 62 and the lower edge of the overlapping area with the protective end plate 5 is relatively far. This results in the insulating film 6 being located in the area between the hot melt point 62 and the lower edge of the overlapping area with the protective end plate 5, and the connection between it and the protective end plate 5 is not tight. This weakens the wrapping and binding force of the insulating film 6 on the electrode group 2, making it easy for gaps to be generated between the insulating film 6 and the electrode group 2, which does not meet the usage requirements.

[0141] Optionally, such as Figure 2 , Figure 3 , Figure 9 , Figure 11 As shown, step S6 further includes the following steps:

[0142] S61. The first upper insulating part 121 is provided with a first mounting groove 125 on the side away from the outer shell body 11, and the second upper insulating part 321 is provided with a second mounting groove 325 on the side away from the cover plate body 31. The battery also includes a connecting piece 8, which is inserted into the first mounting groove 125 and the second mounting groove 325.

[0143] S62, bend the portion of the electrode lug 21 that extends out of the second through structure 124 and the third through structure 324, and weld the bent electrode lug 21 to the connecting piece 8;

[0144] S63, the battery also includes a sealing ring 9, which is installed into the first receiving groove 113 and the second receiving groove 311;

[0145] S64. Insert the composite pole 4 into the first receiving groove 113 and the second receiving groove 311;

[0146] S65, welded composite pole 4 and composite cover plate 3, and composite pole 4 and composite shell 1.

[0147] By setting the connecting piece 8 and welding the electrode 21 to the connecting piece 8, the position of the electrode 21 can be fixed in advance by using the connecting piece 8, ensuring the accuracy of the position of the electrode 21 during subsequent operations, and avoiding the influence of the current conduction effect between the electrode 21 and the composite electrode post 4 due to the misalignment of the electrode 21.

[0148] Optionally, step S7 further includes the following steps:

[0149] S71, the connecting piece 8 is provided with a connecting boss 81 protruding close to the composite pole 4 on the side facing the composite pole 4, and the composite pole 4 is pre-welded and positioned on the connecting boss 81 by a plurality of spaced second pre-welding points.

[0150] S72. Fully weld the composite pole 4 to the connecting boss 81.

[0151] Optionally, such as Figure 2 , Figure 3 , Figure 4 As shown, step S65 further includes the following steps:

[0152] S651, the composite pole 4 includes a pole body 41, a welding ring 42, and a third insulating layer 43 for achieving an insulating connection between the pole body 41 and the welding ring 42. The welding ring 42 is pre-welded and positioned in the first receiving groove 113 and the second receiving groove 311 through multiple spaced third pre-welding points.

[0153] S652, Weld the welding ring 42 fully into the first receiving groove 113 and the second receiving groove 311.

[0154] Optionally, such as Figure 2 , Figure 3 , Figure 4 , Figure 13 As shown, the protective end plate 5 is provided with a shaping structure 52 on the side facing the pole group 2, which corresponds one-to-one with the first through structure 51. The shaping structure 52 is a horn shape with the opening gradually narrowing away from the pole group 2, which provides better support and fixation for the multiple converging pole ears 21 on the pole group 2.

[0155] In this embodiment, as Figure 2 As shown, a battery is also provided, which is assembled using the battery assembly method described above. This allows for a further increase in the volume of the electrode assembly 2, thereby improving the energy density of the battery and increasing its power supply capacity.

[0156] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A battery assembly method, characterized in that, The battery assembled using the battery assembly method includes a composite casing, electrode assembly, composite cover plate, composite terminal post, and protective end plate. The battery assembly method includes the following steps: S1. The electrode assembly includes a first surface and a second surface with electrode tabs, and a plurality of side surfaces perpendicular to the first surface and the second surface. A first through structure is provided on the protective end plate. The protective end plate is installed on the first surface and / or the second surface of the electrode assembly, and the electrode tabs pass through the first through structure. S2. Cover the outside of the electrode group with an insulating film, so that the insulating film covers the outside of the plurality of sides, and heat-melt the insulating film to the protective end plate to form an electrode group unit; S3. The composite shell is a single-sided open structure with a cavity. A second through structure for the electrode tab to extend is provided on the wall opposite to the open side, and a first insulating layer for isolating the composite shell from the electrode tab is injection molded on the wall. The electrode assembly unit is installed into the cavity of the composite shell, and the electrode tab that passes through the first through structure passes through the second through structure. S4. The composite cover plate has a third through structure for the electrode tab to extend out and a second insulating layer for isolating the composite cover plate from the electrode tab. The composite cover plate is placed at the opening of the composite shell, and the electrode tab that passes through the first through structure passes through the third through structure. S5. Weld the composite cover plate to the composite outer shell; S6. A first receiving groove is provided on the side of the composite shell away from the electrode group, and a second receiving groove is provided on the side of the composite cover plate away from the electrode group. The composite electrode post is installed into the first receiving groove and the second receiving groove, and the composite electrode post is welded to the composite cover plate and the composite shell. S7. Enable current conduction between the composite electrode post and the electrode tab.

2. The battery assembly method according to claim 1, characterized in that, Step S2 also includes the following steps: S21. The battery further includes at least one protective side plate, and at least one of the protective side plates is pre-heat-melted to a predetermined position on the insulating film; S22. The insulating film is wrapped around a plurality of the sides of the electrode assembly, and at least one of the protective side plates covers one of the sides of the electrode assembly; S23. The overlapping area between the insulating film and the protective end plate is heat-fused.

3. The battery assembly method according to claim 2, characterized in that, Step S21 also includes the following steps: S211. A positioning hole is made at the designated position of the insulating film; S212. The protective side plate is provided with a positioning structure that cooperates with the positioning hole. The protective side plate is located at a set position of the insulating film, and the positioning structure is aligned with the positioning hole. S213. The assembled protective side plate and the insulating film are heat-fused together.

4. The battery assembly method according to claim 2, characterized in that, Step S23 also includes the following steps: S231. The composite cover plate is pre-installed on the side of the protective end plate away from the electrode group, and the electrode lug that passes through the first through structure passes through the third through structure. S232. Measure the distance L1 between the nearest point between the composite cover plate and the insulating film, and determine whether L1 satisfies 0.5mm≤L1≤3mm. If yes, proceed to step S233; otherwise, proceed to step S234. S233. After removing the pre-installed composite cover plate, the overlapping area between the insulating film and the protective end plate is heat-fused to form the electrode unit. S234. After removing the pre-installed composite cover plate, cut the insulating film. After the cutting is completed, proceed to step S231.

5. The battery assembly method according to claim 2, characterized in that, The overlapping area between the insulating film and the protective end plate is provided with a plurality of spaced hot melting points. The distance between the boundary of each hot melting point on the side away from the electrode group and the boundary of the overlapping area on the side away from the electrode group is L2, and satisfies 0.5mm≤L2≤3mm. And / or, the distance between the boundary of each of the hot melting points facing the electrode group and the boundary of the overlapping area facing the electrode group is L3, and satisfies 0.5mm≤L3≤3mm.

6. The battery assembly method according to claim 1, characterized in that, Step S5 also includes the following steps: S51. The composite cover plate and the composite shell are pre-welded and positioned through multiple spaced first pre-welding points; S52. Fully weld the composite cover plate to the composite outer shell.

7. The battery assembly method according to claim 1, characterized in that, The composite housing includes a housing body and the first insulating layer; The outer shell body includes a first wall and a plurality of second walls perpendicular to the first wall. The plurality of second walls are arranged around the periphery of the first wall to form a hollow shell structure with one side open. The first receiving groove is opened on the side of the first wall away from the pole group. A first insertion through hole is also opened on the first wall and disposed in the first receiving groove. The first insulating layer is injection molded on the first wall surface and includes a first upper insulating portion, a first lower insulating portion, and a first plug-in portion. The first upper insulating portion is disposed on the side of the first wall surface away from the electrode assembly and located in the first receiving groove. The first lower insulating portion is disposed on the side of the first wall surface facing the electrode assembly. The first plug-in portion is inserted into the first plug-in through hole and is used to connect the first upper insulating portion and the first lower insulating portion. The second through structure penetrates the first upper insulating portion, the first plug-in portion, and the first lower insulating portion.

8. The battery assembly method according to claim 7, characterized in that, The composite cover plate includes a cover plate body and a second insulating layer; The second receiving groove is formed on the cover plate body, and the cover plate body is also provided with a second insertion through hole disposed in the second receiving groove; The second insulating layer is injection molded onto the cover plate body and includes a second upper insulating portion, a second lower insulating portion, and a second insertion portion. The second upper insulating portion is located on the side of the cover plate body away from the electrode assembly and is situated within the second receiving groove. The second lower insulating portion is located on the side of the cover plate body facing the electrode assembly. The second insertion portion is inserted into the second insertion through hole and is used to connect the second upper insulating portion and the second lower insulating portion. The third through structure penetrates the second upper insulating portion, the second insertion portion, and the second lower insulating portion.

9. The battery assembly method according to claim 8, characterized in that, Step S6 also includes the following steps: S61. The first upper insulating part is provided with a first mounting groove on the side away from the outer shell body, and the second upper insulating part is provided with a second mounting groove on the side away from the cover plate body. The battery also includes a connecting piece, which is inserted into the first mounting groove and the second mounting groove. S62. Bend the portion of the electrode tab extending out of the second through structure and the third through structure, and weld the bent electrode tab to the connecting piece; S63. The battery further includes a sealing ring, which is installed into the first receiving groove and the second receiving groove; S64. The composite pole is installed into the first receiving groove and the second receiving groove; S65. Weld the composite pole to the composite cover plate and the composite pole to the composite shell.

10. A battery, characterized in that, The battery is assembled using the battery assembly method as described in any one of claims 1-9.

Images