Secondary battery top cover assembly

Abstract

The present disclosure relates to a secondary battery top cover assembly, comprising: a top cover plate having a first post via hole; the pole is arranged on the top cover plate in an insulating manner; the pole cap is arranged around the outer side of the pole column; the lower support is provided with a second pole via hole, the position of the second pole via hole corresponds to the position of the first pole via hole, and the top cover plate is arranged on the lower support and connected with the lower support; a reinforcing column and a reinforcing hole are formed in the surface, far away from the lower bracket, of the top cover plate and on the outer side of the first pole through hole, the reinforcing column extends in the direction close to the pole cap and is embedded into the pole cap, the reinforcing hole is sunken in the direction far away from the pole cap, and the pole cap extends and is embedded into the reinforcing hole. The connecting stability between the top cover plate and the pole cap can be reinforced, a fixing frame does not need to be welded to the top cover plate, and the top cover plate has the advantages of being stable in structure, easy to assemble and good in product stability.

Description

Technical Field

[0001] The present disclosure relates to the technical field of battery top cover assemblies, and in particular to a secondary battery top cover assembly. Background Art

[0002] In the existing secondary battery top cover assembly structure, such as the common square aluminum shell battery, it generally includes a shell, a battery cell and a top cover assembly. The battery cell is arranged in the shell, and the top cover assembly is used to seal the shell. The top cover assembly usually includes a lower bracket, a top cover plate, a sealing ring and positive and negative bipolar columns.

[0003] When processing the above-mentioned top cover assembly, the sealing ring and the positive and negative poles are sequentially installed into the pole through-holes of the top cover plate, and then the pole cap is injection-molded on the outside of the pole through the injection molding process to fix the pole and the sealing ring on the top cover plate and to insulate the pole from the top cover plate. In this structure, the pole and the top cover plate are connected only by the adhesive force of the pole cap, which has poor stability and is prone to the pole cap falling off the top cover plate.

[0004] Therefore, in the prior art, the connection is reinforced by welding a fixing frame on the outside of the pole through-hole of the top cover plate. The usual practice is to place the sealing ring and the pole in sequence at the pole through-hole of the top cover plate and then weld the fixing frame. This method has high requirements on the placement accuracy of the components and can usually only be performed manually, resulting in low processing efficiency. On the other hand, the high temperature generated during the welding process will affect the stability of the connecting clip structure between the top cover plate and the lower bracket. In addition, the welding slag generated during the welding process will also fall into the gap between the pole and the sealing ring, which is difficult to clean. Moreover, since the welding slag is made of metal material, it will also affect the insulation between the pole and the top cover plate, resulting in the risk of short circuit in the product.

[0005] In summary, the secondary battery top cover assembly in the prior art has the defects of poor connection stability, high assembly difficulty, and poor product stability, and is in urgent need of improvement. Utility Model Content

[0006] To address the aforementioned problems of the prior art, the present invention provides a secondary battery top cover assembly. This assembly can strengthen the connection between the top cover plate and the pole cap without requiring a fixing frame to be welded to the top cover plate, resulting in a stable structure, easy assembly, and good product stability.

[0007] A secondary battery top cover assembly disclosed herein includes:

[0008] A top cover plate having a first pole through hole extending through the top cover plate in a thickness direction;

[0009] A pole, which is insulated and arranged on the top cover plate and located at the first pole through hole;

[0010] a pole cap, which surrounds the outer side of the pole and is connected to the top cover plate, the pole and the fixing frame respectively, so as to insulate the top cover plate, the fixing frame and the pole from each other;

[0011] A lower bracket having a second pole through-hole extending through the lower bracket in a thickness direction, wherein the position of the second pole through-hole corresponds to the position of the first pole through-hole, and the top cover is disposed on and connected to the lower bracket;

[0012] A reinforcement column and a reinforcement hole are formed on the outside of the first pole through hole on the side of the top cover plate away from the lower bracket, the reinforcement column extends toward the pole cap and is embedded in the pole cap, the reinforcement hole is recessed in the direction away from the pole cap, and the pole cap extends to be embedded in the reinforcement hole.

[0013] Preferably, one end of the reinforcement column embedded in the pole cap has a countersunk structure extending outward.

[0014] Preferably, a section of the reinforcement hole close to the pole cap is a first narrow section, and a section away from the pole cap is a first wide section, and the pore cross-section size of the first narrow section is smaller than the pore cross-section size of the first wide section.

[0015] Preferably, a surface of the top cover plate close to the lower bracket is recessed in a direction away from the lower bracket to form a plurality of connecting recessed holes, and a surface of the lower bracket close to the top cover plate is formed with matching heat-melting posts at positions corresponding to the connecting recessed holes, and the heat-melting posts are inserted into the connecting recessed holes;

[0016] The connecting concave hole has a second narrow section at a portion close to the lower bracket and a second wide section at a portion away from the lower bracket, wherein the cross-sectional dimension of the hole of the second narrow section is smaller than the cross-sectional dimension of the hole of the second wide section;

[0017] A surface of the top cover plate close to the lower bracket is provided with a plurality of positioning posts protruding in the direction close to the lower bracket, and a surface of the lower bracket close to the top cover plate is provided with matching positioning holes at positions corresponding to the positioning posts, and the positioning posts are inserted into the positioning holes.

[0018] Preferably, the reinforcement columns and the reinforcement holes are arranged in a circular array, alternately on the outside of the first pole via hole, the position of the connecting recess corresponds to the position of the reinforcement column, and the position of the positioning column corresponds to the position of the reinforcement hole.

[0019] Preferably, the secondary battery top cover assembly further includes:

[0020] A fixing member is provided on a side of the lower bracket away from the top cover plate, and at least a portion of the fixing frame is located outside the second pole through hole and abuts against the lower bracket, and the fixing member is also connected to the pole.

[0021] Preferably, the fixing member has a third pole through-hole corresponding to the second pole through-hole and for accommodating the pole, a surface of the fixing member close to the lower bracket abuts against the lower bracket, and an inner edge of the third pole through-hole is connected to the pole;

[0022] An embedding groove adapted to the fixing member is formed on the outer side of the second pole through hole on a side of the lower bracket away from the top cover plate, and the fixing frame is embedded in the embedding groove.

[0023] Preferably, the end of the pole extends into the embedding groove, and the fixing piece is in the shape of a flat plate and is sleeved on the outside of the entry portion of the pole;

[0024] Alternatively, the end of the pole is located outside the embedding groove, and the fixing piece has an inner edge portion extending into the second pole through-hole and sleeved on the outer side of the pole, and the inner side surface of the inner edge portion is a sloped surface, so that the aperture of the third pole through-hole gradually decreases in the direction approaching the lower bracket.

[0025] Preferably, the secondary battery top cover assembly further includes a sealing ring, which is arranged between the electrode and the top cover plate;

[0026] The lower bracket is hollowed out in the middle of its length direction to form a plurality of elastic shrinkage holes;

[0027] At least one edge of the pole is recessed inward to form a locking groove.

[0028] The advantages of the secondary battery top cover assembly disclosed in the present disclosure are:

[0029] 1. The present invention provides a reinforcement column and a reinforcement hole on the top cover plate, so that after the pole cap is formed by injection molding, the reinforcement column can be embedded in the pole cap, and the pole cap will extend to be embedded in the reinforcement hole, thereby reinforcing the stability of the connection between the pole cap and the top cover plate, effectively reducing the risk of the pole cap falling off the top cover plate, and eliminating the need to weld a fixing frame on the top cover plate, thereby reducing the requirements for component placement accuracy and facilitating automated processing. At the same time, it also avoids the problem of welding slag generated during the welding process being difficult to clean, affecting the insulation between the top cover plate and the pole column and causing product short circuits, thereby helping to improve the stability of product quality.

[0030] 2. The end of the reinforcement column disclosed in the present invention is a countersunk structure, and the reinforcement hole has a first narrow section and a first wide section, which can further enhance the stability of the connection with the top cover plate and the pole cap;

[0031] 3. The top cover plate and the lower bracket of the present disclosure adopt a method of combining a connecting concave hole with a hot melt pin to replace the existing snap-fit ​​connection structure. The hot melt pin is inserted into the connecting concave hole. The hot melt pin can be heated to melt and form a colloid that fills the connecting concave hole. After cooling and forming, the top cover plate and the lower bracket are connected. Compared with the snap-fit ​​structure, this connection structure greatly enhances the stability of the connection between the top cover plate and the lower bracket, effectively reduces the risk of the top cover plate and the lower bracket falling off, and has a simple structure and is easy to implement.

[0032] 4. The present disclosure provides positioning posts and positioning holes on the pole and the lower bracket, which facilitates rapid assembly of the pole and the lower bracket and helps improve production efficiency. Furthermore, the structure of the connecting recessed hole, the positioning posts, the reinforcement posts, and the reinforcement holes is cleverly combined, so that when the reinforcement posts are stamped, the connecting recessed hole is formed on the back of the top cover plate, and when the reinforcement holes are stamped, the positioning posts are formed on the back of the top cover plate. This allows for rapid processing and molding, greatly saving the processing steps of the top cover plate and saving the material cost of the top cover plate.

[0033] 5. The present invention increases the stability of the connection between the pole and the top cover plate and the lower bracket by adding a fixing piece on the back of the lower bracket to limit the pole from dislocating upward, thereby effectively preventing the pole from falling off upward and improving the stability of the overall structure of the top cover assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 Schematic diagram of the structure of the secondary battery top cover assembly according to this embodiment;

[0035] Figure 2 Schematic diagram of the structure of the top cover plate of this embodiment;

[0036] Figure 3 yes Figure 2 Schematic diagram of the structure after installing the sealing ring;

[0037] Figure 4 yes Figure 3 Schematic diagram of the structure after adding poles;

[0038] Figure 5 yes Figure 4 Schematic diagram of the structure after the pole cap is formed by injection molding;

[0039] Figure 6 yes Figure 5 Schematic diagram of the structure after installing explosion-proof valve;

[0040] Figure 7 yes Figure 6 Schematic diagram of the structure after assembling the lower bracket;

[0041] Figure 8 is a top view of the secondary battery top cover assembly according to this embodiment;

[0042] Figure 9 yes Figure 8 Sectional view at the middle AA position;

[0043] Figure 10 is a top view of the secondary battery top cover assembly with a fixing member installed in this embodiment;

[0044] Figure 11 is a schematic structural diagram of the fixing member described in Example 1;

[0045] Figure 12 yes Figure 10 Cross-sectional view of the middle BB position (Example 1);

[0046] Figure 13 is a schematic structural diagram of the fixing member described in Example 2;

[0047] Figure 14 yes Figure 10 Cross-sectional view of the middle BB position (Example 2);

[0048] Figure 15 is a schematic structural diagram of the back side of the top cover plate of this embodiment;

[0049] Figure 16 is a schematic structural diagram of the front side of the lower bracket according to this embodiment;

[0050] Figure 17 Schematic diagram of the structure of the pole described in this embodiment.

[0051] Explanation of the reference numerals: 1-top cover plate, 11-first pole through hole, 12-reinforcement column, 13-reinforcement hole, 14-connecting recess, 15-positioning column, 2-pole, 21-locking groove, 3-pole cap, 4-lower bracket, 41-second pole through hole, 42-hot melt column, 43-positioning hole, 44-elastic shrinkage hole, 5-fixing part, 51-third pole through hole, 52-inner edge, 6-sealing ring, 7-explosion-proof valve, A-welding point position A, B-welding point position B. DETAILED DESCRIPTION

[0052] like Figures 1-17 As shown, a secondary battery top cover assembly according to the present disclosure includes:

[0053] Top cover 1, as detailed Figure 2 As shown, the top cover plate 1 is typically a square plate structure with a first terminal through-hole 11 extending through the thickness of the plate for the terminal 2 to pass through, thereby electrically connecting the terminal 2 to the battery cell inside the battery casing. In a bipolar structure, there are typically two first terminal through-holes 11, one at each end of the top cover plate 1 along its length, corresponding to the positive and negative terminals, respectively.

[0054] There are usually two poles 2, one for positive and one for negative. Figure 17 As shown, the shape and size of the pole 2 generally correspond to the first pole through-hole 11 and are made of a conductive material. For the negative pole, the upper portion is required to be made of aluminum and the lower portion is required to be made of copper. In this embodiment, the pole 2 has a cylindrical structure. In other optional embodiments, the pole 2 can be a quadrangular prism or other special-shaped structure. This disclosure does not limit the specific shape of the pole 2. The pole 2 is insulated and arranged on the top cover plate 1 and is located at the first pole through-hole 11 of the top cover plate 1.

[0055] The pole cap 3 is usually formed by injection molding of plastic material. It is arranged around the outside of the pole 2 and is respectively connected to the top cover plate 1, the fixing frame and the pole 2 to connect the three components into one and achieve insulation sealing between the components.

[0056] The lower bracket 4 is typically made of insulating plastic. It is an elongated plate that fits snugly within the top cover 1 and connects to the top and bottom covers. It serves to separate and insulate the top cover 1 from the battery casing, preventing contact between the top cover 1 and the battery cells inside the casing, which could cause a short circuit. The lower bracket 4 has a second terminal via 41 extending through the thickness of the battery, located at a position corresponding to the first terminal via 11.

[0057] In this embodiment, a reinforcement column 12 and a reinforcement hole 13 are formed on the outside of the first pole through hole 11 on the side of the top cover plate 1 away from the lower bracket 4, that is, on the front side. The reinforcement column 12 extends in the direction close to the pole cap 3, that is, extends upward. After the pole cap 3 is formed by injection molding, the reinforcement column 12 will be embedded in the interior of the pole cap 3. The reinforcement hole 13 is concave in the direction away from the pole cap 3, that is, downward. When the pole cap 3 is formed by injection molding, the colloid of the pole cap 3 will flow into the reinforcement hole 13, and the glue column formed after cooling and molding will be embedded in the reinforcement hole 13. The structure of the reinforcement column 12 and the reinforcement hole 13 can increase the contact area between the pole cap 3 and the top cover plate 1 when the pole cap 3 is formed by injection molding, that is, increase the bonding area between the pole cap 3 and the top cover plate 1, thereby enhancing the connection stability between the pole cap 3 and the top cover plate 1, and further enhancing the connection stability between the pole 2 and the top cover plate 1, reducing the risk of the pole 2 falling off the top cover plate 1.

[0058] Furthermore, the main body of the reinforcement column 12 is a cylindrical structure that is easy to process. At one end where the pole cap 3 is embedded, that is, the upper end, there is a countersunk structure that extends outward, so that the diameter of this end is larger than the diameter of the main body of the reinforcement column 12. The countersunk structure will significantly increase the limiting effect of the reinforcement column 12 on the pole cap 3 in the vertical direction, making it difficult for the pole cap 3 to separate upward from the top cover plate 1, and also making it difficult for the injection-molded pole 2-pole cap 3 as a whole to separate upward from the top cover plate 1, thereby effectively reducing the risk of the pole 2 falling off and improving the stability of the assembly structure of the pole 2.

[0059] More specifically, the reinforcement hole 13 is an inverted countersunk hole structure, with the section close to the pole cap 3, i.e. the upper section, being the first narrow section, and the section away from the pole cap 3, i.e. the lower section, being the first wide section, that is, the reinforcement hole 13 has a structure in which the upper section is narrow and the lower section is wide, so that when the pole cap 3 is formed by injection molding, the colloid will flow into the reinforcement hole 13, and after molding, a part embedded in the reinforcement hole 13 will be formed. Due to the above-mentioned reinforcement hole 13 structure, the top cover plate 1 has a good effect of limiting the upward dislocation of this part of the pole cap 3, and then, in conjunction with the structure of the aforementioned reinforcement column 12, it can well limit the upward dislocation of the pole cap 3, thereby significantly increasing the connection stability between the pole column 2, the pole cap 3 and the top cover plate 1.

[0060] The top cover plate 1 is provided with a plurality of connecting recesses 14 on one side close to the lower bracket 4, that is, the back side, which is concave upward in the direction away from the lower bracket 4. The lower bracket 4 is provided with a plurality of matching heat-melt posts 42 on the one side close to the top cover plate 1, that is, the front side, at positions corresponding to the connecting recesses 14. The heat-melt posts 42 are inserted into the connecting recesses 14. Specifically, the connecting recesses 14 are circular holes, and there are four of them, which are evenly distributed on the periphery of the first pole through-hole 11. The number of heat-melt posts 42 is adapted to the connecting recesses 14. After the top cover plate 1 and the lower bracket 4 are covered, the heat-melt posts 42 will be inserted into the connecting recesses 14 one by one. At this time, local heating is performed on the heat-melt posts 42, which will cause the heat-melt posts 42 to melt and form a colloid to fill the connecting recesses 14. After cooling and forming, the top cover plate 1 is connected to the lower bracket 4. Compared with the snap connection method, this connection structure can greatly enhance the connection stability between the top cover plate 1 and the lower bracket 4.

[0061] The section of the connecting recessed hole 14 close to the lower bracket 4, i.e., the lower section, is the second narrow section, and the section away from the lower bracket 4, i.e., the upper section, is the second wide section. The cross-sectional size of the channel of the second narrow section is smaller than the cross-sectional size of the channel of the second wide section, so that the connecting recessed hole 14 has a structure with a large upper end and a small lower end. This structure can form a countersunk columnar structure after the colloid is cooled and formed, has good vertical tensile strength, and can effectively prevent the top cover plate 1 and the lower bracket 4 from falling off and separating.

[0062] When assembling the top cover plate 1 and the lower bracket 4, it is necessary to ensure that the top cover plate 1 and the lower bracket 4 are aligned up and down. In this embodiment, the side of the top cover plate 1 close to the lower bracket 4, that is, the back side along the direction close to the lower bracket 4, is formed with a plurality of positioning columns 15 protruding downward. The positioning columns 15 are cylindrical, and the side of the lower bracket 4 close to the top cover plate 1, that is, the front side is formed with matching positioning holes 43 at positions corresponding to the positioning columns 15. The positioning columns 15 are inserted into the positioning holes 43 to achieve the top and bottom alignment of the top cover plate 1 and the lower bracket 4, ensuring the alignment accuracy.

[0063] In the aforementioned top cover plate 1 structure, the reinforcement column 12 is an upwardly protruding structure, the connecting recessed hole 14 is an upwardly recessed structure, the reinforcement hole 13 is a downwardly recessed structure, and the positioning column 15 is a downwardly protruding structure. If they are processed separately, multiple steps are required to form the aforementioned top cover plate 1 structure, which increases the complexity of the process and the processing cost. In this embodiment, the structure of the thin plate of the top cover plate 1 is combined, and the reinforcement column 12 can be formed by stamping. At the same time, the stamping will form a stamping hole on the back of the top cover plate 1. The reinforcement column 12 and the reinforcement hole 13 are cleverly arranged in a circular array and alternately arranged on the outside of the first pole through-hole 11, and the position of the connecting recessed hole 14 corresponds to the position of the reinforcement column 12, and the position of the positioning column 15 corresponds to the position of the reinforcement hole 13. Therefore, in actual processing, when the reinforcement column 12 is stamped on the back of the top cover plate 1, the stamping hole formed on the back serves as the connecting recessed hole 14, and when the reinforcement hole 13 is stamped on the front of the top cover plate 1, the column protruding from the back serves as the positioning column 15. Through the structural design of this embodiment, the processing of the four structures of the reinforcement column 12, the reinforcement hole 13, the connecting recessed hole 14, and the positioning column 15 can be completed through two simple stamping processes, which greatly saves the processing steps and can effectively reduce the complexity of the process and the processing cost of the top cover plate 1. On the other hand, the reinforcing columns 12 and the reinforcing holes 13 are arranged in a circular array and alternately, so that the reinforcing effect of the reinforcing columns 12 and the reinforcing holes 13 on the pole 2 and the top cover plate 1 is uniform, making the outer side of the pole 2 not easy to fall off, thereby achieving a uniform and stable reinforcement effect on the pole 2.

[0064] In order to further strengthen the installation of the pole 2 on the top cover plate 1 and prevent the pole 2 from falling off upward, in this embodiment, the secondary battery top cover assembly further includes:

[0065] The fixing member 5 is made of metal material to facilitate welding to the pole 2. The fixing member 5 is arranged on the side of the lower bracket 4 away from the top cover plate 1, that is, on the back side, and at least a portion of the fixing member is located outside the second pole through-hole 41 and abuts against the lower bracket 4. The fixing member 5 is also connected to the pole 2, so that the fixing member 5 and the pole 2 form an integral structure, and a portion of the fixing member 5 abuts against the back side of the lower bracket 4, and the abutting portion is located outside the second pole through-hole 41. That is, when the pole 2 has a tendency to move upward, the pole 2 will drive the fixing member 5 to move upward synchronously. At this time, since a portion of the fixing member 5 abuts against the outside of the second pole through-hole 41, the lower bracket 4 limits the fixing member 5, thereby limiting the pole 2, so that the pole 2 cannot move upward to escape. Therefore, the fixing member 5 can limit the pole 2 from escaping upward.

[0066] Furthermore, in this embodiment, the fixing member 5 has a hollow structure, and has a third pole through-hole 51 in the middle corresponding to the second pole through-hole 41 and for accommodating the pole 2. The side of the fixing member 5 close to the lower bracket 4 is located on the outside of the second pole through-hole 41 and abuts against the lower bracket 4. The inner edge of the third pole through-hole 51 is welded to the pole 2, so that the fixing member 5 is connected to the pole 2 to form an integrated structure.

[0067] Furthermore, in this embodiment, a side of the lower bracket 4 away from the top cover plate 1, i.e., the back side, is formed with an embedding groove adapted to the fixing member 5 on the outside of the second pole through-hole 41. The size of the embedding groove is slightly larger than the size of the fixing member 5, so that a portion of the fixing member 5 can be embedded in the embedding groove, and the fixing member 5 is positioned to facilitate quick and accurate installation of the fixing member 5.

[0068] The connection structure between the pole 2 and the fixing member 5 has at least the following two implementations:

[0069] Example 1

[0070] Details such as Figure 11 、 Figure 12 As shown, the thickness of the pole 2 is relatively large, so that after the pole 2 is installed on the top cover plate 1, the lower end of the pole 2 will extend to enter the embedding groove, and the fixing member 5 is a circular ring with a flat sheet structure. The fixing member 5 is embedded in the embedding groove. The third pole through-hole 51 in the middle of the fixing member 5 surrounds the outside of the part where the end of the pole 2 enters the embedding groove, and is welded to the end of the pole 2 at the welding point position A, so that the pole 2 and the fixing member 5 form an integrated structure.

[0071] Example 2

[0072] Details such as Figure 13 、 Figure 14As shown, the thickness of the pole 2 is relatively small. After the pole 2 is installed on the top cover plate 1, the lower end of the pole 2 is located outside the embedding groove, that is, it does not enter the embedding groove. At this time, the fixing piece 5 installed in the embedding groove cannot directly contact and connect with the pole 2. Therefore, the fixing piece 5 has an inner edge portion 52 that extends into the second pole through-hole 41 of the lower bracket 4 and is sleeved on the outer side of the pole 2. The inner edge portion 52 is cylindrical and sleeved on the outer side of the end of the pole 2 and is welded to the pole 2 at the welding point position B, so that the pole 2 and the fixing piece 5 form an integrated structure.

[0073] For more details, please refer to Figure 14 The inner side surface of the inner edge portion 52 is a sloped surface, so that the aperture of the third pole through hole 51 gradually decreases as it approaches the lower bracket 4. That is, the third pole through hole 51 of the fixing member 5 has a structure with a large upper end and a small lower end. This structure makes it easy to insert the fixing member 5 from bottom to top into the outer side of the pole 2 in the second pole through hole 41, so as to facilitate quick installation of the fixing member 5.

[0074] Both embodiments of the connection structure between the pole 2 and the fixing member 5 described above enable the fixing member 5 to be connected to the pole 2 to form an integrated structure, and the fixing member 5 and the pole 2 are then limited by the lower bracket 4 to prevent the pole 2 from moving upward and dislocating. In Example 1, the fixing member 5 has a simple circular ring structure, which is easy to process, but the thickness of the pole 2 must be processed larger, which increases the material cost of the pole 2. In Example 2, the thickness of the pole 2 is smaller, and the material cost is low, but the structure of the fixing member 5 is relatively complex, and the processing steps and material costs are relatively high. Both methods have their own advantages and disadvantages, and can be selected according to the actual application process.

[0075] Furthermore, in this embodiment, the top cover assembly also includes a sealing ring 6, which is annular and is arranged between the pole 2 and the top cover plate 1, and is located on the outside of the first pole through-hole 11. The sealing ring 6 is used to achieve insulation sealing between the pole 2 and the top cover plate 1.

[0076] like Figure 16 As shown, the lower bracket 4 is hollowed out in the middle of its length direction to form a number of elastic shrinkage holes 44. Since the lower bracket 4 is made of plastic material and has a certain material elasticity, when assembled with the top cover plate 1, it is easy to have a certain dimensional error due to external factors such as temperature changes, resulting in an inability to cover the top cover plate 1 with the assembly. Therefore, in this embodiment, by hollowing out the middle of the lower bracket 4 to form an elastic shrinkage hole 44, the lower bracket 4 can be fine-tuned in length through the elastic shrinkage hole 44 therein, so that the lower bracket 4 is adapted to the size of the top cover plate 1, thereby improving the assembly success rate between the top cover plate 1 and the lower bracket 4 and reducing the assembly difficulty.

[0077] like Figure 17As shown, in order to prevent the cylindrical pole 2 and the pole cap 3 from rotating relative to each other, in this embodiment, the edge of the pole 2 is recessed inward to form a locking groove 21. When the pole cap 3 is injection-molded, the colloid will enter the locking groove 21. After cooling and molding, the relative rotation of the pole 2 and the pole cap 3 can be locked, thereby keeping the pole 2 in a fixed state and reducing the risk of the pole 2 shifting and falling off.

[0078] This embodiment also provides a method for processing a secondary battery top cover assembly, which is used to process the secondary battery top cover assembly described above, and includes the following steps:

[0079] S01. Prepare a suitable top cover plate 1, a pole 2, and a lower bracket 4 for use. A reinforcement column 12 and a reinforcement hole 13 are formed on the outer side of the first pole through hole 11 on the side of the top cover plate 1 away from the lower bracket 4. Specifically, the above components are stamped out of metal material. If a structure with a fixing member 5 is used, the fixing member 5 is also stamped out in this step.

[0080] S02, such as Figure 3 、 Figure 4 As shown, take the sealing ring 6, and install the sealing ring 6 and the pole 2 into the first pole through hole 11 of the top cover plate 1 in sequence, or pre-assemble the sealing ring 6 and the pole 2 and then install them into the first pole through hole 11 of the top cover plate 1;

[0081] S03, such as Figure 5 As shown, the integrated structure formed by the top cover plate 1, the sealing ring 6 and the pole 2 is placed in a mold and the pole cap 3 is formed by injection molding on the outside of the pole 2. After the injection molding is completed, the reinforcement column 12 of the top cover plate 1 is embedded in the interior of the pole cap 3, and the pole cap 3 extends to be embedded in the reinforcement hole 13;

[0082] S04, such as Figure 6 As shown, the explosion-proof valve 7 is installed in the explosion-proof valve 7 installation hole of the top cover plate 1;

[0083] S05, such as Figure 7 As shown, the lower bracket 4 is connected to the top cover plate 1 to obtain a top cover assembly. If a structure with a fixing member 5 is used, the fixing member 5 is welded to the back of the lower bracket 4 in this step. Specifically, the third pole through hole 51 of the fixing member 5 is sleeved on the outer side of the pole 2. The fixing member 5 and the pole 2 are welded on the contact surface to ensure a firm connection between the fixing member 5 and the pole 2.

[0084] S06. The top cover assembly is subjected to an automated clamping assembly line operation and laser QR code marking, and a protective film of the explosion-proof valve 7 is affixed to the explosion-proof valve 7. Then, helium testing, negative electrode insulation resistance, negative electrode insulation withstand voltage, positive electrode to top cover plate resistance, shaping and other related station tests are performed. After all tests are qualified, the lithium battery top cover assembly is obtained as a finished product;

[0085] Among them, step S04 can be swapped to before any step of step S02 or step S03.

[0086] The present invention provides a reinforcing column 12 and a reinforcing hole 13 on the top cover plate 1, so that the reinforcing column 12 can be embedded in the pole cap 3 after the pole cap 3 is formed by injection molding, and the pole cap 3 will extend to be embedded in the reinforcing hole 13, thereby reinforcing the stability of the connection between the pole cap 3 and the top cover plate 1, effectively reducing the risk of the pole cap 3 falling off the top cover plate 1, and eliminating the need to weld a fixing frame on the top cover plate 1, thereby reducing the requirement for component placement accuracy and facilitating automated processing. At the same time, it also avoids the problem of welding slag generated during the welding process being difficult to clean, affecting the insulation between the top cover plate 1 and the pole 2 and causing a short circuit in the product, thereby helping to improve the stability of product quality.

[0087] The end of the reinforcement column 12 disclosed in the present invention is a countersunk structure, and the reinforcement hole 13 has a first narrow section and a first wide section, which can further enhance the stability of the connection with the top cover plate 1 and the pole cap 3;

[0088] The top cover plate 1 and the lower bracket 4 of the present disclosure adopt a method of matching the connecting concave hole 14 with the hot melt column 42 to replace the existing snap-fit ​​connection structure. The hot melt column 42 is inserted into the connecting concave hole 14. The hot melt column 42 can be heated to melt and form a colloid that fills the connecting concave hole 14. After cooling and forming, the top cover plate 1 and the lower bracket 4 are connected. Compared with the snap-fit ​​structure, this connection structure greatly enhances the stability of the connection between the top cover plate 1 and the lower bracket 4, effectively reduces the risk of the top cover plate 1 and the lower bracket 4 falling off, and has a simple structure and is easy to implement.

[0089] The present disclosure provides positioning posts 15 and positioning holes 43 on the pole 2 and the lower bracket 4, which can facilitate the rapid assembly of the pole 2 and the lower bracket 4, thereby helping to improve production efficiency. On the other hand, the structures of the connecting recessed hole 14, the positioning posts 15, the reinforcing posts 12, and the reinforcing holes 13 are cleverly combined, so that when the reinforcing posts 12 are stamped, the connecting recessed hole 14 is formed on the back of the top cover plate 1, and when the reinforcing holes 13 are stamped, the positioning posts 15 are formed on the back of the top cover plate 1. This allows one-step processing and forming, greatly saving the processing steps of the top cover plate 1 and saving the material cost of the top cover plate 1.

[0090] The present disclosure adds a fixing member 5 on the back side of the lower bracket 4, and limits the pole 2 from dislodging upward through the fixing member 5, thereby improving the stability of the connection between the pole 2, the top cover plate 1 and the lower bracket 4, effectively preventing the pole 2 from falling off upward, and improving the stability of the overall structure of the top cover assembly.

[0091] In the description of the present disclosure, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present disclosure and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present disclosure.

[0092] Those skilled in the art can make various other corresponding changes and deformations based on the technical solutions and concepts described above, and all of these changes and deformations should fall within the scope of protection of the claims of this disclosure.

Claims

1. A secondary battery top cover assembly, characterized in that: include: A top cover plate having a first pole through hole extending through the top cover plate in a thickness direction; A pole, which is insulated and arranged on the top cover plate and located at the first pole through hole; a pole cap, which surrounds the outer side of the pole and is connected to the top cover plate, the pole and the fixing frame respectively, so as to insulate the top cover plate, the fixing frame and the pole from each other; A lower bracket having a second pole through-hole extending through the lower bracket in a thickness direction, wherein the position of the second pole through-hole corresponds to the position of the first pole through-hole, and the top cover is disposed on and connected to the lower bracket; A reinforcement column and a reinforcement hole are formed on the outside of the first pole through hole on the side of the top cover plate away from the lower bracket, the reinforcement column extends toward the pole cap and is embedded in the pole cap, the reinforcement hole is recessed in the direction away from the pole cap, and the pole cap extends to be embedded in the reinforcement hole.

2. The secondary battery top cover assembly according to claim 1, characterized in that: One end of the reinforcement column embedded in the pole cap has a countersunk structure extending outward.

3. The secondary battery top cover assembly according to claim 1 or 2, characterized in that: The section of the reinforcement hole close to the pole cap is a first narrow section, and the section away from the pole cap is a first wide section. The cross-sectional size of the channel of the first narrow section is smaller than the cross-sectional size of the channel of the first wide section.

4. The secondary battery top cover assembly according to claim 1, characterized in that: A surface of the top cover plate close to the lower bracket is recessed in a direction away from the lower bracket to form a plurality of connection recessed holes, and a surface of the lower bracket close to the top cover plate is formed with matching heat-melting posts at positions corresponding to the connection recessed holes, and the heat-melting posts are inserted into the connection recessed holes; The connecting concave hole has a second narrow section at a portion close to the lower bracket and a second wide section at a portion away from the lower bracket, wherein the cross-sectional dimension of the hole of the second narrow section is smaller than the cross-sectional dimension of the hole of the second wide section; A surface of the top cover plate close to the lower bracket is provided with a plurality of positioning posts protruding in the direction close to the lower bracket, and a surface of the lower bracket close to the top cover plate is provided with matching positioning holes at positions corresponding to the positioning posts, and the positioning posts are inserted into the positioning holes.

5. The secondary battery top cover assembly according to claim 4, characterized in that: The reinforcement columns and the reinforcement holes are arranged in a circular array and alternately outside the first pole through-hole. The positions of the connecting recesses correspond to the positions of the reinforcement columns, and the positions of the positioning columns correspond to the positions of the reinforcement holes.

6. The secondary battery top cover assembly according to claim 1, characterized in that: Also includes: A fixing member is provided on a side of the lower bracket away from the top cover plate, and at least a portion of the fixing frame is located outside the second pole through hole and abuts against the lower bracket, and the fixing member is also connected to the pole.

7. The secondary battery top cover assembly according to claim 6, characterized in that: The fixing member has a third pole through-hole corresponding to the second pole through-hole and used to accommodate the pole, a surface of the fixing member close to the lower bracket abuts against the lower bracket, and an inner edge of the third pole through-hole is connected to the pole; An embedding groove adapted to the fixing member is formed on the outer side of the second pole through hole on a side of the lower bracket away from the top cover plate, and the fixing frame is embedded in the embedding groove.

8. The secondary battery top cover assembly according to claim 7, characterized in that: The end of the pole extends into the embedding groove, and the fixing piece is in the shape of a flat plate and is sleeved on the outside of the entry portion of the pole; Alternatively, the end of the pole is located outside the embedding groove, and the fixing piece has an inner edge portion extending into the second pole through-hole and sleeved on the outer side of the pole, and the inner side surface of the inner edge portion is a sloped surface, so that the aperture of the third pole through-hole gradually decreases in the direction approaching the lower bracket.

9. The secondary battery top cover assembly according to claim 1, characterized in that: It also includes a sealing ring, which is arranged between the pole and the top cover plate; The lower bracket is hollowed out in the middle of its length direction to form a plurality of elastic shrinkage holes; At least one edge of the pole is recessed inward to form a locking groove.

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