Top cover assembly, battery monomer, battery pack and preparation method of battery monomer

Abstract

A top cover assembly, a battery monomer, a battery pack and a preparation method of the battery monomer, the top cover assembly is adapted to the battery monomer, and comprises a battery connecting piece, a base plate, a pole and a tab connecting piece; the base plate is provided with a mounting hole; the pole is provided with a through hole; the pole is located in the mounting hole; the extension direction of the through hole is parallel to the extension direction of the mounting hole; the tab connecting piece comprises a connecting piece body and a protruding connecting part; the protruding connecting part extends outward from the plane where the connecting piece body is located; the battery connecting piece is used for connecting the current battery monomer and an external element, and comprises a protruding mounting part; the battery connecting piece is attached to the edge of the mounting hole on the base plate, the protruding mounting part is located in the first section of the through hole; the protruding connecting part is located in the second section of the through hole and is in contact with the protruding mounting part. The top cover assembly accommodates the protruding mounting part through the ear connecting piece and the recess formed on the pole, reduces the probability of fire explosion in the welding process, and improves the production yield of the top cover assembly.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a top cover assembly, a battery cell, a battery pack, and a method for preparing the battery cell. Background Art

[0002] A battery cell is typically connected to external components or other battery cells via a battery connector such as a tab. This is typically achieved by welding the battery connector to the top cover assembly of another battery cell.

[0003] Currently, most top cover components are welded to battery connectors. This is due to factors such as poor heat distribution at the weld joint and limited contact area between the shielding gas and the weld. This leads to a high welding yield.

[0004] In other words, the structural design of most current top cover components results in a low yield rate in their production process. Summary of the Invention

[0005] The purpose of this application is to provide a top cover assembly, a battery cell, a battery pack and a method for preparing a battery cell, which can effectively avoid the explosion phenomenon during the welding process between the battery connector and the top cover assembly, thereby improving the production yield of the top cover assembly.

[0006] In the first aspect, the present application provides a top cover assembly, which is adapted for a battery cell and includes a battery connector, a substrate, a pole and a tab connecting piece; a mounting hole is provided on the substrate; a through hole is provided on the pole; the pole is located in the mounting hole; wherein the extension direction of the through hole is parallel to the extension direction of the mounting hole; the tab connecting piece includes a connecting piece body and a raised connecting portion; the raised connecting portion extends outward from the plane where the connecting piece body is located; the battery connector is used to connect the current battery cell and an external component, and includes a raised mounting portion; the battery connector is attached to the edge of the mounting hole on the substrate, and the raised mounting portion is located in the first section of the through hole; the raised connecting portion is located in the second section of the through hole and contacts the raised mounting portion.

[0007] The top cover assembly can accommodate the protruding mounting portion of the battery connecting member through the recess formed on the pole and the tab connecting piece mounted on the substrate. In the case of accommodating the protruding mounting portion in the recess, the contact part is welded. The recess formed by the pole and the tab connecting piece can increase the heat concentration area, and accordingly, the protruding mounting portion of the battery connecting member helps to disperse the heat, so that the heat is more evenly distributed, thereby avoiding the rapid evaporation of materials and the rapid expansion of gas caused by high temperature. Finally, the probability of fire during welding is reduced. Accordingly, the production yield of the top cover assembly is improved.

[0008] In combination with the first aspect, optionally, an inner diameter of the first section of the through hole is greater than an inner diameter of the second section of the through hole; an outer diameter of the protruding mounting portion matches the inner diameter of the first section of the through hole; an edge portion of the protruding mounting portion abuts against the first step, and a middle portion of the protruding mounting portion abuts against the protruding connecting portion; wherein the first step is located at a connection between the first section of the through hole and the second section of the through hole.

[0009] In the top cover assembly, the inner diameter of the first section of the through hole is greater than the inner diameter of the second section of the through hole, so that a first step is formed inside the through hole, and the end surface of the protruding mounting portion is in contact with the step and the end surface of the protruding connecting portion, respectively, thereby dispersing the stress applied by the protruding mounting portion to the tab connecting piece. Moreover, the contact area of the protruding mounting portion with the pole is increased, thereby further improving the yield of welding.

[0010] In combination with the first aspect, optionally, further comprising an outer plastic; the outer plastic is filled between the inner wall of the mounting hole and the pole and between the battery connecting member and the substrate.

[0011] In the top cover assembly, the gap between the battery connecting member and the substrate is filled by the outer plastic, so that the space formed by the battery connecting member and the through hole of the substrate is sealed, thereby protecting the internal parts of the top cover assembly.

[0012] In combination with the first aspect, optionally, further comprising an inner plastic; the mounting hole comprises a lower section of the mounting hole close to one end of the tab body, an upper section of the mounting hole away from the one end of the tab body, and a middle section of the mounting hole between the lower section of the mounting hole and the upper section of the mounting hole; an inner diameter of the middle section of the mounting hole is greater than an inner diameter of the upper section of the mounting hole and an inner diameter of the lower section of the mounting hole; the outer plastic is filled between the inner wall of the upper section of the mounting hole and the pole and between the battery connecting member and the substrate; the inner plastic is filled between the inner wall of the middle section of the mounting hole and the pole.

[0013] The top cover assembly further improves the sealing of the space formed by the battery connecting member and the through hole of the substrate by the structure of the middle section of the mounting hole corresponding to the groove on the inner wall of the mounting hole and filling the gap between the middle section of the mounting hole and the pole column with the inner plastic, thereby better protecting the internal parts of the top cover assembly.

[0014] In combination with the first aspect, the sealing ring is filled between the inner wall of the lower section of the mounting hole and the pole column and between the inner plastic and the pole column.

[0015] The top cover assembly realizes the sealing between the lower section of the mounting hole and the pole column by filling the gap between the inner wall of the lower section of the mounting hole and the pole column with the sealing ring, effectively isolates the positive and negative materials in the battery monomer and the conductive elements, and effectively prevents electrical short circuit, thereby improving the safety of the battery monomer.

[0016] In combination with the first aspect, the inner plastic includes an upper portion of the inner plastic close to the connecting piece body, a lower portion of the inner plastic away from the connecting piece body, and a middle portion of the inner plastic between the upper portion and the lower portion of the inner plastic; the upper portion of the inner plastic is attached to the second step and surrounds the outer plastic; the middle portion of the inner plastic surrounds the pole column; and the lower portion of the inner plastic is attached to the third step and surrounds the sealing ring.

[0017] The top cover assembly further improves the sealing of the space formed by the battery connecting member and the through hole of the substrate by the structure of the middle section of the mounting hole corresponding to the groove on the inner wall of the mounting hole and filling the gap between the middle section of the mounting hole and the pole column with the inner plastic, thereby better protecting the internal parts of the top cover assembly.

[0018] In combination with the first aspect, the pole column includes a lower section of the pole column close to one end of the connecting piece body, an upper section of the pole column away from one end of the connecting piece body, and a middle section of the pole column between the lower section and the upper section of the pole column; the outer diameter of the middle section of the pole column is greater than the outer diameters of the upper section and the lower section of the pole column.

[0019] The top cover assembly further improves the sealing effect by the outer diameter of the middle section of the pole column being greater than the outer diameters of the two sections of the pole column, being covered by the inner plastic, and filling the gap between the middle section of the pole column and the mounting hole with the inner plastic, thereby further improving the sealing effect. In addition, the protruding structure of the middle section of the pole column also prevents the inner plastic from moving.

[0020] In a second aspect, the application provides a battery cell, comprising an electrode core and the top cover assembly described in the first aspect; the top cover assembly is installed on the end of the electrode core; the battery cell further comprises the electrode core and a tab; the tab extends from the edge of the end of the electrode core to the middle of the end of the electrode core and is attached to the end of the electrode core; the connecting piece body is attached to the end of the electrode core and is in contact with the tab.

[0021] The battery cell has the beneficial effects of the first aspect or any one of the optional embodiments of the first aspect, which will not be repeated here.

[0022] In a third aspect, the application provides a battery pack, comprising at least two battery cells described in the second aspect; the battery cells are electrically connected through the battery connector.

[0023] The battery pack has the beneficial effects of the second aspect, which will not be repeated here.

[0024] In a fourth aspect, the application provides a preparation method of a battery cell, for preparing the battery cell described in the second aspect; the method comprises: attaching the connector body of the tab connecting piece in the top cover assembly to the end of the electrode core and welding the tab connecting piece with the tab of the electrode core; installing the pole in the mounting hole of the base plate; passing the protruding connecting part of the tab connecting piece into the through hole of the pole and welding the protruding connecting part with the inner wall of the through hole to obtain a bare battery cell; and wrapping the electrode core in the bare battery cell with a shell and welding the contact between the shell and the top cover assembly.

[0025] The preparation method of the battery cell has the beneficial effects of the second aspect, which will not be repeated here.

[0026] In summary, the top cover assembly, the battery monomer, the battery pack and the preparation method of the battery monomer provided by the application can accommodate the protruding mounting part of the battery connecting piece in the recess formed on the pole column through the tab connecting piece mounted on the substrate. In the case of accommodating the protruding mounting part in the recess, the contact part is welded, which reduces the probability of fire explosion in the welding process, and accordingly improves the production yield of the top cover assembly. The design that the inner diameter of the first section of the through hole is larger than the inner diameter of the second section of the through hole forms a first step inside the through hole, increases the contact area of the protruding mounting part and the pole column, and further improves the yield of welding. The gap between the inner wall of the lower section of the mounting hole and the pole column is filled by the sealing ring, which realizes the sealing between the lower section of the mounting hole and the pole column, effectively isolates the positive and negative materials and the conductive elements inside the battery monomer, and effectively prevents electrical short circuit. The tab extends from the edge of the end of the battery cell to the middle of the end of the battery cell and is attached to the end of the battery cell, so that the bending of the tab is L-shaped. Compared with the bending of the tab in most current battery monomers, which is S-shaped, the space between the battery cell and the top cover assembly in the height direction is saved. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor.

[0028] Figure 1 The first exploded view of the top cover assembly provided by the embodiments of the application;

[0029] Figure 2 The top view and the sectional view along line aa of the top cover assembly provided by the embodiments of the application;

[0030] Figure 3 The Figure 2 The local enlarged view of A in FIG. 4;

[0031] Figure 4 The second exploded view of the top cover assembly provided by the embodiments of the application;

[0032] Figure 5 The structure diagram of the inner plastic of the top cover assembly provided by the embodiments of the application;

[0033] Figure 6 The front view and the sectional view along line bb of the battery monomer provided by the embodiments of the application;

[0034] Figure 7 The Figure 6A local enlarged view at B;

[0035] Figure 8 A perspective view of a battery pack provided for embodiments of the present application;

[0036] Figure 9 A flow chart of a method for preparing a battery cell provided for embodiments of the present application.

[0037] Icon: 100, top cover assembly; 110, battery connecting piece; 111, protruding mounting portion; 120, base plate; 121, mounting hole; 1211, lower section of mounting hole; 1212, upper section of mounting hole; 1213, middle section of mounting hole; 1214, second step; 1215, third step; 130, pole post; 131, through hole; 1311, first step; 132, lower section of pole post; 133, upper section of pole post; 134, middle section of pole post; 140, tab connecting piece; 141, connecting piece body; 142, protruding connecting portion; 150, outer plastic; 160, inner plastic; 161, upper section of inner plastic; 162, lower section of inner plastic; 163, middle section of inner plastic; 170, sealing ring; 180, lower plastic; 10, battery cell; 200, battery core; 210, tab; 1, battery pack. DETAILED DESCRIPTION

[0038] In order to make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some but not all of the embodiments of the present application. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0039] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative labor are within the scope of protection of the present application.

[0040] It should be noted that: similar reference numerals and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0041] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, or the orientation or positional relationship commonly used when the product of the present application is used, and are merely intended to facilitate the description of the present application and simplify the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" and the like are only used to distinguish descriptions and cannot be understood as indicating or implying relative importance.

[0042] In addition, the terms "horizontal", "vertical" and the like do not mean that the components must be absolutely horizontal or vertical, but can be slightly inclined. For example, "horizontal" only means that it is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0043] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "arrangement", "installation", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0044] Please refer to Figures 1 to 4 , Figure 1 is the first exploded view of the top cover assembly 100 provided by the embodiments of the present application; Figure 2 is a top view and a sectional view along line aa of the top cover assembly 100 provided by the embodiments of the present application; Figure 3 is Figure 2 is a local enlarged view of A in Figure 4is a second exploded view of the top cover assembly 100 provided by the embodiments of the present application. The top cover assembly 100 provided by the embodiments of the present application can be adapted to the battery monomer 10 and can include a battery connecting piece 110, a base plate 120, a pole 130, and a tab connecting piece 140. The base plate 120 can be provided with a mounting hole 121. The pole 130 can be provided with a through hole 131. The pole 130 can be located in the mounting hole 121. The extension direction of the through hole 131 can be parallel to the extension direction of the mounting hole 121. The tab connecting piece 140 can include a connecting piece body 141 and a protruding connecting portion 142. The protruding connecting portion 142 can extend outward from the plane where the connecting piece body 141 is located. The battery connecting piece 110 can be used to connect the current battery monomer 10 and an external element and can include a protruding mounting portion 111. The battery connecting piece 110 can be attached to the edge of the mounting hole 121 on the base plate 120, and the protruding mounting portion 111 can be located in the first section of the through hole 131. The protruding connecting portion 142 can be located in the second section of the through hole 131 and can be in contact with the protruding mounting portion 111.

[0045] The battery connecting piece 110 can be a bar. The base plate 120 is generally used to integrate or support various components in the top cover assembly 100 and can be made of insulating material. The pole 130 is generally used as an output terminal of the battery monomer 10. The tab connecting piece 140 is generally used to connect the tab 210 of the battery cell 200 and the pole 130. The external element can be another battery monomer 10 or other electrical equipment. For example, in a battery pack 1 composed of battery monomers 10 arranged in a "one" shape, the battery monomers 10 located at the two ends can be connected to the electrical equipment through the battery connecting piece 110.

[0046] In the through hole 131 of the pole 130, a part contains the protruding connecting portion 142 of the tab connecting piece 140, and another part contains the protruding mounting portion 111 of the battery connecting piece 110. That is, the protruding mounting portion 111 of the battery connecting piece 110 is contained in the recess formed on the pole 130 and the tab connecting piece 140 attached to the base plate 120.

[0047] In the above implementation process, the protruding mounting portion 111 of the battery connecting piece 110 can be contained in the recess formed on the pole 130 and the tab connecting piece 140 attached to the base plate 120. In the case that the protruding mounting portion 111 is contained in the recess, the contact part is welded. The recess formed by the pole 130 and the tab connecting piece 140 can increase the heat concentration area, and accordingly, the protruding mounting portion 111 of the battery connecting piece 110 helps to disperse the heat, so that the heat is more evenly distributed, thereby avoiding the rapid evaporation of materials and the rapid expansion of gas caused by high temperature. Finally, the probability of explosion in the welding process is reduced. Accordingly, the production yield of the top cover assembly 100 is improved.

[0048] Please continue to refer to Figure 3 and Figure 4 In some optional embodiments, the inner diameter of the first section of the through hole 131 can be greater than the inner diameter of the second section of the through hole 131. The outer diameter of the protruding mounting portion 111 can match the inner diameter of the first section of the through hole 131. The edge portion of the protruding mounting portion 111 can abut against the first step 1311, and the middle portion of the protruding mounting portion 111 can abut against the protruding connecting portion 142. The first step 1311 can be located at the connection between the first section of the through hole 131 and the second section of the through hole 131.

[0049] The first section of the through hole 131 can be the upper section of the through hole 131, and the second section of the through hole 131 can be the lower section of the through hole 131. The inner diameter of the upper section of the through hole 131 can be greater than the inner diameter of the lower section of the through hole 131. In the case where the outer diameter of the protruding mounting portion 111 matches the inner diameter of the lower section of the through hole 131, the end surface of the protruding mounting portion 111 can be in contact with the end surface of the first step 1311 and the end surface of the protruding connecting portion 142, respectively.

[0050] In the above implementation process, by designing the inner diameter of the first section of the through hole 131 to be greater than the inner diameter of the second section of the through hole 131, a first step 1311 is formed inside the through hole 131, and the end surface of the protruding mounting portion 111 is in contact with the end surface of the step and the end surface of the protruding connecting portion 142, respectively, thereby dispersing the stress applied by the protruding mounting portion 111 to the tab connecting piece 140. In addition, the contact area between the protruding mounting portion 111 and the pole 130 is increased, thereby further improving the yield of welding.

[0051] Please continue to refer to Figure 3 and Figure 4 In some optional embodiments, the top cover assembly 100 provided by the embodiments of the present application can further include an outer plastic 150. The outer plastic 150 can be filled between the pole 130 and the inner wall of the mounting hole 121 and between the battery connecting piece 110 and the substrate 120.

[0052] The outer plastic 150 can fill part of the gap between the pole 130 and the mounting hole 121, or can fill the entire gap between the pole 130 and the mounting hole 121.

[0053] In the above implementation process, by filling the gap between the battery connecting piece 110 and the substrate 120 with the outer plastic 150, the space formed by the battery connecting piece 110 and the through hole 131 of the substrate 120 is sealed, thereby protecting the internal parts of the top cover assembly 100.

[0054] Please continue to refer to Figure 3 and Figure 4In some alternative embodiments, the top cover assembly 100 can further include an inner plastic 160. The mounting hole 121 can include a lower mounting hole section 1211 near one end of the tab body 141, an upper mounting hole section 1212 away from the one end of the tab body 141, and a middle mounting hole section 1213 between the lower mounting hole section 1211 and the upper mounting hole section 1212. The inner diameter of the middle mounting hole section 1213 can be larger than the inner diameter of the upper mounting hole section 1212 and the inner diameter of the lower mounting hole section 1211. The outer plastic 150 can be filled between the inner wall of the upper mounting hole section 1212 and the pole 130, and between the battery connector 110 and the substrate 120. The inner plastic 160 can be filled between the inner wall of the middle mounting hole section 1213 and the pole 130.

[0055] That is, the inner wall of the mounting hole 121 has a groove thereon, which can correspond to the middle mounting hole section 1213. Alternatively, the inner diameter of the lower mounting hole section 1211 can be smaller than the inner diameter of the upper mounting hole section 1212. The thickness of the substrate 120 at the edge of the mounting hole 121 can be greater than the thickness of the substrate 120 at other positions.

[0056] In the above implementation, the structure of the middle mounting hole section 1213 corresponding to the groove on the inner wall of the mounting hole 121, and the gap between the middle mounting hole section 1213 and the pole 130 being filled by the inner plastic 160, further improves the sealing of the space formed by the through hole 131 of the battery connector 110 and the substrate 120. Thus, the internal components of the top cover assembly 100 are better protected.

[0057] Please continue to refer to Figure 3 and Figure 4 In some alternative embodiments, the top cover assembly 100 can further include a sealing ring 170. The sealing ring 170 can be filled between the inner wall of the lower mounting hole section 1211 and the pole 130, and between the inner plastic 160 and the pole 130.

[0058] As an alternative embodiment, the top cover assembly 100 can further include a lower plastic 180, and the lower plastic 180 can have a lower plastic 180 through hole 131 formed therein. The lower plastic 180 can be attached to the side of the substrate 120 away from the battery connector 110. Correspondingly, the lower plastic 180 can be sleeved on the end of the pole 130 away from the battery connector 110.

[0059] On the basis of the sealing ring 170 filling the gap between the inner wall of the lower mounting hole section 1211 and the pole 130, the sealing ring 170 can also be in contact with the edge of the lower plastic 180 through hole 131 of the lower plastic 180.

[0060] In the implementation process, the gap between the inner wall of the lower section 1211 of the mounting hole and the pole 130 is filled by the sealing ring 170, thereby achieving sealing between the lower section 1211 of the mounting hole and the pole 130, effectively isolating the positive and negative materials inside the battery monomer 10 and the conductive elements, and effectively preventing electrical short circuit. Therefore, the safety of the battery monomer 10 is improved.

[0061] Please refer to Figure 3 Refer to Figure 5 , Figure 5 The structure diagram of the inner plastic 160 in the top cover assembly 100 provided by the embodiment of the present application is shown. In some optional embodiments, the inner plastic 160 can include an inner plastic upper portion 161 close to the connecting piece body 141, an inner plastic lower portion 162 away from the connecting piece body 141, and an inner plastic middle portion 163 between the inner plastic upper portion 161 and the inner plastic lower portion 162. The inner plastic upper portion 161 is attached to the second step 1214 and can be wrapped around the outer plastic 150. The second step 1214 can be located at the connection between the upper section 1212 of the mounting hole and the middle section 1213 of the mounting hole. The inner plastic middle portion 163 is wrapped around the pole 130. The inner plastic lower portion 162 can be attached to the third step 1215 and can be wrapped around the sealing ring 170. The third step 1215 can be located at the connection between the lower section 1211 of the mounting hole and the middle section 1213 of the mounting hole.

[0062] Exemplarily, as shown in the cross-sectional view, Figure 3 The interface of the inner plastic 160 can be a U-shaped interface after being rotated counterclockwise by 90°. The inner plastic 160 can cover the middle section 134 of the pole and contact the sealing ring 170 and the outer plastic 150, respectively.

[0063] In the implementation process, the inner plastic 160 covers the middle section 134 of the pole and contacts the sealing ring 170 and the outer plastic 150, respectively, thereby further improving the sealing performance of the connection between the substrate 120 and the pole 130 and better protecting the internal parts of the top cover assembly 100.

[0064] Please continue to refer to Figure 3 and Figure 4 In some optional embodiments, the pole 130 can include a lower section 132 of the pole close to one end of the connecting piece body 141, an upper section 133 of the pole away from one end of the connecting piece body 141, and a middle section 134 of the pole between the lower section 132 of the pole and the upper section 133 of the pole. The outer diameter of the middle section 134 of the pole can be greater than the outer diameter of the upper section 133 of the pole and the outer diameter of the lower section 132 of the pole.

[0065] As an optional embodiment, the outer diameter of the upper section 133 of the pole can be greater than the outer diameter of the lower section 132 of the pole.

[0066] The middle section 134 of the pole can correspond to a flange. The flange can be covered by the inner plastic 160.

[0067] In the above implementation process, the outer diameter of the middle section 134 of the pole is greater than the outer diameter of the two sections of the pole 130, and the middle section 134 of the pole is covered by the inner plastic 160, and the gap between the middle section 134 of the pole and the mounting hole 121 is filled by the inner plastic 160, thereby increasing the contact area between the pole 130 and the inner plastic 160, and further improving the sealing effect. In addition, the protruding structure of the middle section 134 of the pole also plays a role in preventing the inner plastic 160 from moving.

[0068] Please refer to Figure 6 and Figure 7 , Figure 6 is a front view and a sectional view along line bb of the battery monomer 10 provided by the embodiment of the application; Figure 7 is Figure 6 a partial enlarged view at B in FIG. 10. Based on the same concept, the embodiment of the application provides a battery monomer 10, which can include a battery cell 200 and the top cover assembly 100 described above. The top cover assembly 100 can be mounted on the end of the battery cell 200. The battery monomer 10 can also include the battery cell 200 and the tab 210. The tab 210 can extend from the edge of the end of the battery cell 200 to the middle of the end of the battery cell 200, and can be attached to the end of the battery cell 200. The connecting piece body 141 can be attached to the end of the battery cell 200, and can be in contact with the tab 210.

[0069] The tab 210 extends from the edge of the end of the battery cell 200 to the middle of the end of the battery cell 200, and is attached to the end of the battery cell 200, so that the bending of the tab 210 is L-shaped, compared with the bending of the tab 210 being S-shaped in most of the current battery monomers 10, the space between the battery cell 200 and the top cover assembly 100 in the height direction is saved.

[0070] The above implementation process can be the same as the top cover assembly 100 described above, which will not be described here.

[0071] Please refer to Figure 8 , Figure 8 is a perspective view of the battery pack 1 provided by the embodiment of the application. Based on the same concept, the embodiment of the application provides a battery pack 1, which can include at least two battery monomers 10 as described above. The battery monomers 10 are electrically connected through the battery connecting piece 110.

[0072] The above implementation process can be the same as the battery monomer 10 described above, which will not be described here.

[0073] Please refer to Figure 9 , Figure 9is a flow chart of the method for manufacturing the battery cell provided by the embodiments of the present application. Based on the same concept, the embodiments of the present application provide a method for manufacturing a battery cell, which can be used to manufacture the battery cell 10 described above. The method can include:

[0074] Step S110: The connecting body of the tab connecting piece in the top cover assembly is attached to the end of the battery cell, and is welded with the tab of the battery cell.

[0075] In the step S110 described above, the welding between the connecting body and the tab can be ultrasonic welding.

[0076] Step S120: The pole is installed in the mounting hole of the substrate.

[0077] Step S130: The protruding connecting part of the tab connecting piece is inserted into the through hole of the pole, and the protruding connecting part is welded with the inner wall of the through hole to obtain a bare battery cell.

[0078] In the step S130 described above, the welding between the protruding connecting part and the inner wall of the through hole can be laser welding.

[0079] Step S140: The battery cell in the bare battery cell is wrapped with the shell, and the shell is welded with the contact part of the top cover assembly.

[0080] In the step S140 described above, the welding between the shell and the contact part of the top cover assembly can also be laser welding.

[0081] The implementation process described above can be the same as the battery cell described above, and will not be repeated here.

[0082] In summary, the top cover assembly 100, the battery monomer 10, the battery pack 1 and the preparation method of the battery monomer provided by each embodiment of the present application can accommodate the protruding mounting portion 111 of the battery connecting piece 110 through the recess formed on the pole column 130 and the tab connecting piece 140 installed on the substrate 120. In the case of accommodating the protruding mounting portion 111 in the recess, the contact part is welded, which reduces the probability of explosion during welding, and accordingly improves the production yield of the top cover assembly 100. Through the design that the inner diameter of the first section of the through hole 131 is larger than the inner diameter of the second section of the through hole 131, the first step 1311 is formed inside the through hole 131, which increases the contact area of the protruding mounting portion 111 and the pole column 130, thereby further improving the yield of welding. The gap between the inner wall of the mounting hole lower section 1211 and the pole column 130 is filled by the sealing ring 170, which realizes the sealing between the mounting hole lower section 1211 and the pole column 130, effectively isolates the positive and negative materials and each conductive element inside the battery monomer 10, and effectively prevents electrical short circuit. The tab 210 extends from the edge of the end of the battery cell 200 to the middle of the end of the battery cell 200 and is attached to the end of the battery cell 200, so that the bending of the tab 210 is L-shaped. Compared with the bending of the tab 210 in most battery monomers 10, which is S-shaped, the space between the battery cell 200 and the top cover assembly 100 in the height direction is saved.

[0083] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Those skilled in the art can make various modifications and changes to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A cap assembly, characterized by, The battery monomer is adapted to, and includes a battery connecting piece, a base plate, a pole and a tab connecting piece; The base plate is provided with a mounting hole; The pole is provided with a through hole; the pole is located in the mounting hole; wherein the extension direction of the through hole is parallel to the extension direction of the mounting hole; The tab connecting piece includes a connecting piece body and a protruding connecting part; the protruding connecting part extends outward from the plane where the connecting piece body is located; The battery connecting piece is used for connecting the current battery monomer and external elements, and includes a protruding mounting part; the battery connecting piece is attached to the edge of the mounting hole on the base plate, and the protruding mounting part is located in the first section of the through hole; The protruding connecting part is located in the second section of the through hole and is in contact with the protruding mounting part; The inner diameter of the first section of the through hole is greater than the inner diameter of the second section of the through hole; The outer diameter of the protruding mounting part matches the inner diameter of the first section of the through hole; The edge part of the protruding mounting part is in abutment with a first step, and the middle part of the protruding mounting part is in abutment with the protruding connecting part; wherein the first step is located at the connection between the first section of the through hole and the second section of the through hole.

2. The roof assembly of claim 1, wherein, Further including an outer plastic; The outer plastic is filled between the pole and the inner wall of the mounting hole and between the battery connecting piece and the base plate.

3. The roof assembly of claim 2, wherein, Further including an inner plastic; The mounting hole includes a lower section of the mounting hole close to one end of the connecting piece body, an upper section of the mounting hole away from one end of the connecting piece body, and a middle section of the mounting hole between the lower section of the mounting hole and the upper section of the mounting hole; The inner diameter of the middle section of the mounting hole is greater than the inner diameter of the upper section of the mounting hole and the inner diameter of the lower section of the mounting hole; The outer plastic is filled between the inner wall of the upper section of the mounting hole and the pole and between the battery connecting piece and the base plate; The inner plastic is filled between the inner wall of the middle section of the mounting hole and the pole.

4. The roof assembly of claim 3, wherein, Further including a sealing ring; The sealing ring is filled between the inner wall of the lower section of the mounting hole and the pole and between the inner plastic and the pole.

5. The roof assembly of claim 4, wherein, The inner plastic includes an upper part of the inner plastic close to the connecting piece body, a lower part of the inner plastic away from the connecting piece body, and a middle part of the inner plastic between the upper part of the inner plastic and the lower part of the inner plastic; The upper part of the inner plastic is attached to a second step and surrounds the outer plastic; wherein the second step is located at the connection between the upper section of the mounting hole and the middle section of the mounting hole; The middle part of the inner plastic surrounds the pole; The lower part of the inner plastic is attached to a third step and surrounds the sealing ring; wherein the third step is located at the connection between the lower section of the mounting hole and the middle section of the mounting hole.

6. The roof assembly of claim 1, wherein, The pole includes a lower section of the pole close to one end of the connecting piece body, an upper section of the pole away from one end of the connecting piece body, and a middle section of the pole between the lower section of the pole and the upper section of the pole; The outer diameter of the middle section of the pole is greater than the outer diameter of the upper section of the pole and the outer diameter of the lower section of the pole.

7. A battery cell characterized by, The battery monomer further includes an electric core and a top cover assembly as claimed in any one of claims 1 to 6; The top cover assembly is installed at the end of the electric core; The battery monomer further includes an electric core and a tab. The tab extends from an edge of an end of the cell to a middle of the end of the cell and is attached to the end of the cell. The tab body is attached to the end of the cell and is in contact with the tab.

8. A battery pack, characterized by, The battery cell includes at least two battery cells as claimed in any one of claims 1 to 7. The battery cells are electrically connected through the battery connector.

9. A method of producing a battery cell, characterized by, A method for manufacturing the battery cell as claimed in claim 7. The method includes: attaching the connector body of the tab connector of the top cover assembly to the end of the cell and welding the tab connector of the top cover assembly to the tab of the cell; mounting the pole in the mounting hole of the base plate; passing the protruding connection part of the tab connector into the through hole of the pole and welding the protruding connection part to the inner wall of the through hole to obtain a bare battery cell; and wrapping the cell in the bare battery cell with a shell and welding the shell to the contact of the top cover assembly.

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