Cover plate structure of cylindrical battery

Abstract

The invention belongs to the technical field of batteries, discloses a cover plate structure of a cylindrical battery, solves the problems of stability of anti-explosion scribed lines and timely valve opening of the anti-explosion scribed lines in the prior art, reduces the risk of assembly deviation in the assembly process of a plurality of structural parts, and effectively and integrally solves the problems that a current collecting disc is difficult to assemble and the like. The invention relates to a high-voltage current collector, which solves the problem of insulation between a cover plate and a shell, avoids the risk of internal short circuit, and comprises a central pole, the lower part of the central pole is electrically connected with a gasket and a current collector plate in sequence, a cover plate main body is also arranged between the gasket and the central pole, an insulation sealing ring is arranged above the cover plate main body, and a lower insulation ring is arranged at the lower end of the cover plate main body. A U-shaped anti-explosion scribed line design is adopted, cracks caused by an original V-shaped sharp corner in the anti-explosion scribed line machining process can be avoided, the machining stability of the anti-explosion scribed line is improved, an insulating plastic structure is simplified, an outer insulating ring and an insulating sealing ring are combined into a whole, gaps and micelles caused by uneven glue extrusion are avoided, and the service life of the anti-explosion scribed line is prolonged. And the sealing effect of the cover plate is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a cover plate structure of a cylindrical battery. Background Art

[0002] The battery cover is a precision structural part of the power battery. In a broad sense, it includes the battery cell top cover, steel / aluminum shell, positive and negative soft connections, battery connections, etc. In a narrow sense, it mainly includes the battery cell shell and top cover, which has a direct impact on the safety, airtightness, energy efficiency, etc. of the battery. According to the different battery packaging technology routes, there are mainly three shapes: square, cylindrical, and soft pack. The corresponding structural parts are square structural parts, cylindrical structural parts and aluminum-plastic film. Overall, the cylinder and square are collectively called hard shells, and the packaging structure is relatively similar, both consisting of a shell and a cover. The packaging of soft-pack batteries is relatively special and is made of aluminum-plastic film. The existing battery cover structure is fixed by mechanical rolling between the battery cap and the battery shell. The two rely on an insulating sealing ring sandwiched between them to achieve insulation and sealing. During use, the open part of the battery shell is prone to deformation, resulting in poor sealing at the connection between the battery cap and the battery shell, resulting in electrolyte leakage. Some have solved the problem of timely pressure relief when the internal pressure of the battery is too high by setting explosion-proof scale lines, but have not deeply optimized the design of the explosion-proof scale lines to solve the stability problems of the explosion-proof scale lines and the problem of timely opening of the valves of the explosion-proof scale lines.

[0003] For example, CN217158535U discloses a battery cover assembly, a cylindrical battery and a battery pack, including terminals, poles, upper plastic, lower plastic, a cover body, a sealing ring, a sealing pin and a current collector. The battery cover assembly of this utility model is provided with a thinning area on the sealing pin used to seal the injection hole, so that the sealing pin has the function of an explosion-proof valve. On the one hand, the cover assembly does not need to be provided with an additional explosion-proof valve, which reduces the number of parts and components, thereby reducing costs and improving the production efficiency of the cover assembly; on the other hand, it is not necessary to provide an additional installation hole for installing the explosion-proof valve on the cover, which can not only further improve the production efficiency of the cover assembly, but also leave a larger layout space for the injection hole on the cover, so that the injection hole has a sufficiently large aperture, thereby ensuring the stability of the injection process. The most important feature of the structure described in this patent is to improve the production efficiency of the cover by combining the injection hole and the explosion-proof valve into one, but the plastic and the insulating ring are not designed as one piece, which may lead to the risk of assembly deviation of multiple structural parts during the assembly process, and increase the complexity of the overall cover processing. Summary of the invention

[0004] The purpose of the present invention is to solve the deficiencies of the prior art and to provide the following technical solutions: a cover structure for a cylindrical battery, comprising a central pole, the lower part of the central pole being electrically connected to a gasket and a current collecting plate in sequence, a cover body being provided between the gasket and the central collecting plate, an insulating sealing ring being provided above the cover body, and a lower insulating ring being provided at the lower end of the cover body.

[0005] The present invention proposes a new "U"-shaped explosion-proof line and a double-sided explosion-proof groove design, which effectively avoids the damage to the explosion-proof line caused by the external force encountered during the processing, transportation or use of the cover plate or battery. At the same time, the "U"-shaped explosion-proof line design can avoid the cracks caused by the original V-shaped sharp corners during the processing of the explosion-proof line, and improves the processing stability of the explosion-proof line. The battery using this cover plate structure will greatly improve the stability of the battery itself (anti-drop, anti-vibration), thereby extending the service life of the battery as a whole. The cover plate structure proposed by the present invention simplifies the insulating plastic structure, combines the outer insulating ring and the insulating sealing ring into one, and fully considers the deformation of the insulating rubber block. The groove, boss and chamfer of the lower edge of the center hole are designed on the main structure of the cover plate. At the same time, a buffer gap is set between the sealing ring and the lower insulating ring, and the deformation margin of the insulating rubber ring after assembly extrusion is fully considered, which is conducive to the directional extrusion and extension of the insulating sealing ring. The gap and glue group caused by uneven extrusion are avoided, and the sealing effect of the cover plate is greatly improved. The cover plate structure proposed in the present invention is designed with edge wedge-shaped protrusions and buffer gaps in the inner ring in the design of the lower insulating ring, which effectively solves the insulation problem between the collector plate, the cover plate and the shell as a whole, avoiding the risk of internal short circuit. At the same time, in conjunction with the design of the internal explosion-proof groove, the exhaust hole is designed to ensure that when the pressure inside the battery cell is too high, the pressure of the internal gas can be released in time, ensuring the safety of the battery cell during use.

[0006] Preferably, the central pole is made of metal, and the cross-section of the central pole is in a "T" shape. The central pole described in the present invention is made of common metal, such as any one of steel, iron, copper, aluminum, alloy and composite metal materials. The material has moderate hardness and can be riveted. Before riveting, the cross-section of the pole is in a "T" shape, and after the assembly is riveted, it is in an "I" shape.

[0007] Preferably, the cover plate main body structure is circular with a central through hole at the center, the cover plate main body is provided with an annular positioning groove radially outwardly along the central through hole, and the inner edge of the positioning groove is provided with a groove inner edge protrusion.

[0008] The main structure of the cover described in the present invention is circular, with a through hole in the center, and a circular positioning recessed groove is arranged radially outward along the through hole. The purpose of this groove is to better position the installation of the insulating sealing ring during the assembly process. At the same time, a protrusion is arranged on the inner edge of the recessed groove, and the height of the protrusion is set to be between 0.01 and 0.5 mm.

[0009] Preferably, the height of the protrusion on the inner edge of the sink groove is set to between 0.01 mm and 0.5 mm, and the height of the protrusion on the inner edge of the sink groove is less than the depth of the outer edge of the positioning sink groove.

[0010] The height of the protrusion of the present invention is less than the depth of the outer edge of the sink. The setting of the protrusion can better play the role of glue extrusion and bonding. At the same time, the chamfer is set on the lower edge of the central through hole, which can better facilitate the directional glue extrusion and extension of the insulating sealing ring during the riveting process, avoiding the generation of gaps and glue lumps due to uneven glue extrusion, which affects the sealing effect of the entire cover plate.

[0011] Preferably, the lower edge of the central through hole is provided with a chamfer.

[0012] The chamfer provided at the lower edge of the central through hole of the present invention can better facilitate the directional glue extrusion and extension of the insulating sealing ring during the riveting process, avoiding the generation of gaps and glue lumps due to uneven glue extrusion, which affects the sealing effect of the entire cover plate.

[0013] Preferably, an inner explosion-proof groove is provided on the back of the cover body, an outer explosion-proof groove is provided on the front of the cover body, an explosion-proof engraved line is provided at the center of the outer explosion-proof groove of the cover body, and the inner explosion-proof groove and the outer explosion-proof groove are arc-shaped.

[0014] The back side of the cover body described in the present invention (facing the inside of the battery cell) is provided with an inner explosion-proof groove. The front side of the cover body (facing the outside of the battery cell) is provided with an outer explosion-proof groove, and an explosion-proof engraved line is provided at the center of the outer explosion-proof groove. Providing explosion-proof grooves on both the front and back sides can effectively protect the explosion-proof engraved lines and prevent the explosion-proof engraved lines from being damaged by external forces encountered during the processing, transportation or use of the cover or battery. The explosion-proof groove can be set to be circular, semicircular or arc-shaped. The width of the explosion-proof groove can be adjusted according to the design and can be set to 2mm, and the groove is circular.

[0015] The cover body described in the present invention is made of common metal, such as any one of steel, iron, copper, aluminum, alloy and composite metal materials. Preferably, the thickness of the cover body is set to 1.0 mm, and specifically, the diameter of the cover can be selected from other common sizes such as 18 mm, 21 mm, 26 mm, 32 mm, 46 mm and 60 mm.

[0016] Preferably, the depth of the explosion-proof marking line is set to 1 / 5 to 2 / 3 of the thickness of the outer explosion-proof groove and the inner explosion-proof groove, the cross-sectional shape of the explosion-proof marking line is an open "U" shape, the opening angle range is 10° to 60°, the bottom end of the explosion-proof marking line is arc-shaped, and the arc radius setting range is between 0.01mm and 1mm.

[0017] The opening angle θ and arc radius R value selected by the present invention can be adjusted accordingly according to the actual design needs. The opening angle θ value of the present invention can be set to 30°, the arc radius R value is set to 0.03mm, and the depth of the line is set to 1 / 2 of the thickness of the groove. The U-shaped design of the explosion-proof line can avoid the cracks caused by the original V-shaped sharp corners during the processing of the explosion-proof line, and improve the processing stability of the explosion-proof line. At the same time, the explosion-proof line of the present invention can be set to arc, semicircle and circle.

[0018] Preferably, the insulating sealing ring has a right-angle "Z"-shaped cross-section, the upper edge height of the insulating sealing ring is greater than the depth of the outer edge of the groove on the cover plate, the upper end face of the insulating sealing ring is higher than the outer end face of the cover plate body, and the lower edge ring height of the insulating sealing ring is greater than the sum of the thickness of the center through hole and the thickness of the lower insulating ring.

[0019] The insulating sealing ring described in the present invention has a right-angle "Z"-shaped cross-section, and the upper edge height of the sealing ring needs to be greater than the depth of the outer edge of the recessed groove on the cover. That is, after assembly, the upper end face of the insulating sealing ring is higher than the outer end face of the cover body, thereby ensuring the insulation effect between the central pole and the cover body. The height H of the lower edge ring of the sealing ring is greater than the sum of the thickness of the central through hole and the thickness of the lower insulating ring H'. It can be set to 1.2 to 1.8 times. In the present invention, H can be set to 1.5 times H'.

[0020] Preferably, the edge of the lower insulating ring is provided with a lower insulating ring edge protrusion toward the inside of the battery cell, the lower insulating ring edge protrusion is wedge-shaped, the end face of the lower insulating ring edge protrusion is lower than the end face position of the lower surface of the collecting disk after welding, and the inner diameter of the lower insulating ring edge protrusion is larger than the diameter of the collecting disk, and the lower insulating ring is also provided with a lower insulating ring center through hole, the diameter of the lower insulating ring center through hole is larger than the lower end diameter of the central pole, and there is a buffer gap between the edge of the lower insulating ring center through hole and the central pole, and the edge of the lower insulating ring is provided with a circle of several exhaust holes, and the positions of the exhaust holes are connected to the inner explosion-proof groove.

[0021] The main feature of the lower insulating ring described in the present invention is that a wedge-shaped protrusion is set on the edge of the insulating ring toward the inside of the battery cell, and the end face of the protrusion is lower than the end face position of the lower surface of the collector after welding. At the same time, the inner diameter of the protrusion is larger than the diameter of the collector, ensuring that there is a gap between the edge of the collector and the inner edge of the insulating ring protrusion after the welding of the collector and the central pole is completed. This gap can generally be set to 0.2-1mm. At the same time, the outer diameter of the protrusion of the lower insulating ring is smaller than the inner diameter of the careful shell, ensuring that there is a gap between the outer edge of the protrusion and the shell, and the gap can generally be set to 0.2-1mm. At the same time, the diameter of the central through hole of the lower insulating ring is larger than the lower end diameter of the central pole. After assembly, there is a buffer gap between the edge of the central hole of the insulating ring and the central pole. At the same time, an exhaust hole is set on the lower insulating ring, and the position of the exhaust hole must be connected to the inner explosion-proof groove. The exhaust hole can be set to any geometric shape, and the number can also be freely set according to design needs. The present invention can select a circular exhaust hole, 24 in number, and the exhaust hole spacing is uniform. After assembly, the exhaust hole is connected to the internal explosion-proof groove, which ensures that when the pressure inside the battery cell is too high, the gas pressure can be smoothly transmitted to the explosion-proof groove, thereby further triggering the explosion threshold of the explosion-proof scale line, and then smoothly releasing pressure and exhausting air, ensuring the safety of the battery cell during use.

[0022] Preferably, the gasket is in the shape of a circular ring, the size of the center hole of the gasket matches the size of the lower end of the central pole, and the outer diameter of the gasket is smaller than the inner edge diameter of the exhaust hole.

[0023] The main feature of the gasket of the present invention is that it is in the shape of a ring, the size of the center hole of which matches the size of the lower end of the central pole. The material is any one of common metals, such as steel, iron, copper, aluminum, alloy and composite metal materials, or other insulating materials. The outer diameter is smaller than the inner edge diameter of the exhaust hole.

[0024] The beneficial effects of the present invention are as follows: 1. The present invention proposes a new explosion-proof engraved line design, which adopts a double-sided explosion-proof groove design to fully protect the stability of the explosion-proof engraved line, and effectively avoids the damage to the explosion-proof engraved line caused by external forces encountered during the processing, transportation or use of the cover plate or battery. At the same time, the "U"-shaped explosion-proof engraved line design is adopted to avoid the cracks caused by the original V-shaped sharp corners during the processing of the explosion-proof engraved line, thereby improving the processing stability of the explosion-proof engraved line.

[0025] 2. The cover plate structure proposed by the present invention simplifies the insulating plastic structure, combines the outer insulating ring and the insulating sealing ring into one, and fully considers the deformation of the insulating rubber block. The main structure of the cover plate is grooved, the boss and the lower edge chamfer of the center hole are designed, and a buffer gap is set between the sealing ring and the lower insulating ring. The deformation margin of the insulating rubber ring after assembly and extrusion is fully considered, which is conducive to the directional extrusion and extension of the insulating sealing ring. It avoids the generation of gaps and glue lumps caused by uneven extrusion, and greatly improves the sealing effect of the cover plate.

[0026] 3. The cover plate structure proposed in the present invention is designed with edge wedge-shaped protrusions and buffer gaps in the inner ring in the design of the lower insulating ring, which effectively solves the insulation problem between the collector plate, the cover plate and the shell as a whole, avoiding the risk of internal short circuit. At the same time, in conjunction with the design of the internal explosion-proof groove, the exhaust hole is designed to ensure that when the pressure inside the battery cell is too high, the pressure of the internal gas can be released in time, ensuring the safety of the battery cell during use. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is an exploded view of the structure of the present invention; Figure 2 A top view of the present invention; Figure 3 It is a cross-sectional view of the present invention; Figure 4 This is a partial enlarged view of area A of the present invention; Figure 5 This is the explosion-proof engraved structure diagram of the present invention; Figure 6 This is a partial enlarged view of area B of the present invention.

[0028] In the figure: 1-central pole, 2-insulating sealing ring, 3-cover body, 4-lower insulating ring, 5-gasket, 6-collecting plate, 7-buffer gap, 21-upper edge of insulating sealing ring, 22-lower edge of insulating sealing ring, 31-explosion-proof engraved line, 32-external explosion-proof groove, 33-inner explosion-proof groove, 34-positioning sink groove, 35-center through hole, 36-protrusion on the inner edge of the sink groove, 37-chamfered lower edge of the center through hole, 41-center through hole of the lower insulating ring, 42-exhaust hole, 43-protrusion on the edge of the lower insulating ring. DETAILED DESCRIPTION

[0029] The specific implementation of the technical solution of the present invention is further described below through examples and in conjunction with the accompanying drawings.

[0030] Embodiment 1: See also Figure 1 and Figure 2 Embodiment 1 of the present invention provides a cover structure of a cylindrical battery, comprising a central pole 1, an insulating seal ring 2, a cover body 3, a lower insulating ring 4, a gasket 5 and a current collecting plate 6. The central pole 1 is electrically connected to the gasket 5 and the current collecting plate 6, and the cover and the shell are electrically connected. They are physically insulated by the insulating seal ring 2 and the lower insulating ring 4, so that they respectively serve as the two poles (positive or negative) of the battery to form a circuit with the external electrical device.

[0031] like Figure 3As shown, the central pole 1 described in the present invention is made of common metal, such as any one of steel, iron, copper, aluminum, alloy and composite metal materials. The material has moderate hardness and can be riveted. Before riveting, the cross section of the pole is "T" shaped, and after the assembly is riveted, it is "I" shaped.

[0032] The structure of the cover plate body 3 described in the present invention is circular, with a central through hole 35 in the center, and a circular positioning recessed groove 34 radially outwardly arranged along the central through hole 35. The purpose of this groove is to better position the installation of the insulating sealing ring 2 during the assembly process. At the same time, a recessed groove inner edge protrusion 36 is set on the inner edge of the positioning recessed groove 34, and the height of the protrusion is set to be between 0.01 and 0.5 mm, and the height of the protrusion is less than the depth of the outer edge of the recessed groove. In the present embodiment 1, this height is set to 0.15 mm. The setting of this protrusion can better play the role of glue extrusion and bonding. At the same time, a chamfer 37 of the lower edge of the central through hole is set at the lower edge of the central through hole 35. It can be better conducive to the directional glue extrusion and extension of the insulating sealing ring 2 during the riveting process. It avoids the generation of gaps and glue lumps due to uneven glue extrusion, which affects the sealing effect of the entire cover plate.

[0033] The cover plate body 3 described in the present invention is made of common metal, such as any one of steel, iron, copper, aluminum, alloy and composite metal materials. In the embodiment 1 of the present invention, the thickness of the cover plate body 3 is set to 1.0 mm. In subsequent embodiments, the cover plate diameter can be selected from other common sizes such as 18 mm, 21 mm, 26 mm, 32 mm, 46 mm and 60 mm.

[0034] The back side (facing the inside of the battery cell) of the cover body 3 described in the present invention is provided with an inner explosion-proof groove 33. The front side (facing the outside of the battery cell) of the cover body 3 is provided with an outer explosion-proof groove 32, and an explosion-proof mark 31 (31) is provided at the center of the outer explosion-proof groove 32. The explosion-proof grooves are provided on both the front and back sides at the same time, which can effectively protect the explosion-proof mark 31 and prevent the explosion-proof mark 31 from being damaged by external forces encountered during the processing, transportation or use of the cover or battery. The explosion-proof groove can be set to be circular, semicircular or arc-shaped. The width of the explosion-proof groove can be adjusted according to the design. In this embodiment 1, it is set to 2 mm, and the explosion-proof groove is set to be circular.

[0035] The main features of the explosion-proof score line 31 of the present invention are as follows: 1. The depth of the explosion-proof score line 31 is set to 1 / 5 to 2 / 3 of the thickness of the explosion-proof groove (which can be adjusted according to the actual design requirements of the battery cell), see Figure 4 , Figure 4 2. The cross-sectional shape of the explosion-proof score line 31 is an open "U" shape (see convex 5, Figure 5(The enlarged view of the explosion-proof marking line 31) The opening angle θ is between 10 and 60°, the bottom end is arc-shaped, and the arc radius R can be set to between 0.01 and 1 mm. (The selected opening angle θ and arc radius R values ​​can be adjusted accordingly according to the actual design needs). In this embodiment 1, the θ value is set to 30°, and the R value is set to 0.03 mm. At the same time, the depth of the explosion-proof marking line 31 is set to 1 / 2 of the thickness of the groove. The U-shaped design of the explosion-proof marking line 31 can avoid the occurrence of cracks caused by the original V-shaped sharp corners of the explosion-proof marking line 31 during the processing, thereby improving the processing stability of the explosion-proof marking line 31. 3. The explosion-proof marking line 31 can be set to an arc shape. In this embodiment 1, the explosion-proof marking line 31 is set to a semicircle.

[0036] like Figure 3 As shown, the insulating sealing ring 2 described in the present invention has a right-angle "Z"-shaped cross-section, and the height of the upper edge 21 of the insulating sealing ring must be greater than the depth of the outer edge of the positioning groove 34 on the cover. That is, after assembly, the upper end surface of the insulating sealing ring 2 is higher than the outer end surface of the cover body 3, thereby ensuring the insulation effect between the central pole 1 and the cover body 3. The height H of the circular ring of the lower edge 22 of the insulating sealing ring is greater than the sum H' of the thickness of the central through hole 35 and the thickness of the lower insulating ring 4. It can be set to 1.2 to 1.8 times. In this embodiment, H is set to 1.5 times H'.

[0037] The main feature of the lower insulating ring 4 described in the present invention is that a wedge-shaped protrusion is set on the edge of the lower insulating ring 4 toward the inside of the battery cell, and the protrusion is the lower insulating ring edge protrusion 43. The end face of the protrusion is lower than the end face position of the lower surface of the current collecting disk 6 after welding, and the inner diameter of the protrusion is larger than the diameter of the current collecting disk 6, to ensure that after the current collecting disk 6 and the central pole 1 are welded, there is a gap between the edge of the current collecting disk 6 and the inner edge of the insulating ring protrusion. This gap can generally be set to 0.2 to 1 mm. At the same time, the outer diameter of the lower insulating ring edge protrusion 43 is smaller than the inner diameter of the careful shell, to ensure that there is a gap between the outer edge of the protrusion and the shell, and the gap can generally be set to 0.2 to 1 mm. At the same time, the diameter of the central through hole 41 of the lower insulating ring is larger than the lower end diameter of the central pole 1. As Figure 6 As shown, after assembly, there is a buffer gap 7 between the edge of the central through hole 41 of the lower insulating ring and the central pole 1. At the same time, an exhaust hole 42 is set on the lower insulating ring 4, and the position of the exhaust hole 42 must be connected to the inner explosion-proof groove 33. The exhaust hole 42 can be set to any geometric shape, and the number can also be freely set according to design requirements. In this embodiment, a circle is selected as the exhaust hole 42, and the number is set to 24, and the exhaust holes 42 are evenly spaced. After assembly, the exhaust hole 42 is connected to the inner explosion-proof groove 33, thereby ensuring that when the pressure inside the battery cell is too high, the pressure of the gas can be smoothly transmitted to the explosion-proof groove, thereby further triggering the explosion threshold of the explosion-proof mark 31, and then smoothly decompressing and exhausting, ensuring the safety of the battery cell during use.

[0038] The main feature of the gasket 5 of the present invention is that it is annular, and the size of its center hole matches the size of the lower end of the central pole 1. The material is any one of common metals, such as steel, iron, copper, aluminum, alloy and composite metal materials, or other insulating materials. The outer diameter is smaller than the inner edge diameter of the exhaust hole 42.

[0039] The assembly process sequence recommended for the cover structure of the present invention is to first assemble the central pole 1, the insulating seal ring 2 and the cover body 3 from top to bottom, then invert them, place the insulating ring 4 and the gasket 5, and perform riveting of the entire assembly after the installation is completed to ensure that the central pole 1 is compressed into the "I" shape required by the design. The cover and the flow plate are electrically connected at the lower end surface of the central pole 1 by welding, and the welding method can be any one of resistance welding, ultrasonic welding or laser welding.

[0040] Compared with the prior art, the cover body 3 of the present invention is welded to the shell, which has a better sealing effect. The present invention simplifies the insulating plastic structure and adopts the pole, insulating sealing ring 2, cover plate and lower insulating glue to form an integrated riveted structure. Compared with this patent, the present invention directly combines the upper plastic and the insulating ring into one. The risk of assembly deviation of multiple structural parts during assembly is reduced. At the same time, the setting of the injection hole and the sealing nail is cancelled, reducing the complexity of the overall cover processing. At the same time, the present invention directly adds explosion-proof grooves and explosion-proof engraved lines 31 to the cover body 3. It effectively achieves the purpose of pressure relief when the internal pressure of the battery cell is too large, thereby increasing the safety of the battery.

[0041] The present invention combines the outer insulating ring and the insulating sealing ring 2 into one by simplifying the insulating plastic structure, thereby reducing the risk of assembly deviation of multiple structural parts during the assembly process. At the same time, the present invention directly adds explosion-proof grooves and explosion-proof engraved lines 31 designs on the cover plate body 3. It effectively achieves the purpose of pressure relief when the internal pressure of the battery cell is too large, thereby increasing the safety of the battery. The welding method of the current collecting plate 6 and the guide plate in this patent is not easy to implement. The normal assembly order is that the current collecting plate 6 and the winding core are welded first, and after welding, the guide plate is welded to the current collecting plate 6. At this time, there is insufficient welding space and welding is difficult to implement. At the same time, after the guide plate is introduced into the structure described in this patent, the axial thickness of the entire cover plate is increased, which in turn affects the volume energy density of the battery cell. The current collecting plate 6 of the present invention is designed to be directly welded to the lower end face of the central pole 1, which greatly improves the space utilization inside the battery cell.

[0042] Embodiment 2: Embodiment 2 of the present invention provides another cover structure of a cylindrical battery with set parameters, such as Figure 1 and Figure 2As shown, it includes a central pole 1, and the lower part of the central pole 1 is electrically connected to a gasket 5 and a current collecting plate 6 in sequence. A cover plate body 3 is also provided between the gasket 5 and the central collecting column, an insulating sealing ring 2 is provided above the cover plate body 3, and a lower insulating ring 4 is provided at the lower end of the cover plate body 3.

[0043] The present invention proposes a new "U"-shaped explosion-proof line 31 and a double-sided explosion-proof groove design, which effectively avoids the damage to the explosion-proof line 31 caused by the external force encountered during the processing, transportation or use of the cover plate or battery. At the same time, the "U"-shaped explosion-proof line 31 design can avoid the cracks caused by the original V-shaped sharp corners of the explosion-proof line 31 during the processing, and improves the processing stability of the explosion-proof line 31. The battery using this cover plate structure will greatly improve the stability of the battery itself (anti-drop, anti-vibration), thereby extending the service life of the battery as a whole. The cover plate structure proposed by the present invention simplifies the insulating plastic structure, combines the outer insulating ring and the insulating sealing ring 2 into one, and fully considers the deformation of the insulating rubber block. The cover plate body 3 structure is designed with a sink, a boss and a chamfered lower edge of the center hole. At the same time, a buffer gap 7 is set between the sealing ring and the lower insulating ring 4, and the deformation margin of the insulating rubber ring after assembly extrusion is fully considered, which is conducive to the directional extrusion and extension of the insulating sealing ring 2. The generation of gaps and glue lumps caused by uneven glue extrusion is avoided, and the sealing effect of the cover is greatly improved. The cover structure proposed by the present invention is designed with edge wedge-shaped protrusions and a buffer gap 7 on the inner ring in the design of the lower insulating ring 4, which effectively solves the insulation problem between the collector plate 6, the cover plate and the shell as a whole, and avoids the risk of internal short circuit. At the same time, in conjunction with the design of the internal explosion-proof groove 33, the exhaust hole 42 is designed to ensure that when the pressure inside the battery cell is too high, the pressure of the internal gas can be released in time, ensuring the safety of the battery cell during use.

[0044] The central pole 1 is made of metal, such as Figure 3 As shown, the cross-section of the central pole 1 is in the shape of a "T". The central pole 1 described in the present invention is made of a common metal, such as any one of steel, iron, copper, aluminum, alloy and composite metal materials. The material has a moderate hardness and can be riveted. Before riveting, the cross-section of the pole is in the shape of a "T", and after the assembly is riveted, it is in the shape of an "I".

[0045] The cover body 3 is circular in structure, with a central through hole 35 at the center. The cover body 3 is provided with an annular positioning recess 34 radially outwardly along the central through hole 35 , and a recess inner edge protrusion 36 is provided on the inner edge of the positioning recess 34 .

[0046] The cover plate body 3 described in the present invention is circular in structure, with a through hole in the center, and a circular positioning recessed groove 34 is arranged radially outward along the through hole. The purpose of this groove is to better position the installation of the insulating sealing ring 2 during the assembly process. At the same time, a protrusion is arranged on the inner edge of the recessed groove, and the height of the protrusion is set to be between 0.01 and 0.5 mm.

[0047] The height of the protrusion 36 on the inner edge of the groove is set to be between 0.01 mm and 0.5 mm, and the height of the protrusion 36 on the inner edge of the groove is less than the depth of the outer edge of the positioning groove 34 .

[0048] The height of the protrusion of the present invention is less than the depth of the outer edge of the sink. The setting of this protrusion can better play the role of glue extrusion and bonding. At the same time, the chamfer is set at the lower edge of the central through hole 35, which can better facilitate the directional glue extrusion and extension of the insulating sealing ring 2 during the riveting process, avoiding the generation of gaps and glue lumps due to uneven glue extrusion, which affects the sealing effect of the entire cover plate.

[0049] The lower edge of the central through hole 35 is provided with a central through hole lower edge chamfer 37 .

[0050] The chamfer provided at the lower edge of the central through hole 35 of the present invention can better facilitate the directional glue extrusion and extension of the insulating sealing ring 2 during the riveting process, avoiding the generation of gaps and glue lumps due to uneven glue extrusion, which affects the sealing effect of the entire cover.

[0051] like Figure 4 As shown, an inner explosion-proof groove 33 is provided on the back of the cover body 3, an outer explosion-proof groove 32 is provided on the front of the cover body 3, and an explosion-proof engraved line 31 is provided at the center of the outer explosion-proof groove 32 of the cover body 3. The inner explosion-proof groove 33 and the outer explosion-proof groove 32 are arc-shaped.

[0052] The back side (facing the inside of the battery cell) of the cover body 3 described in the present invention is provided with an inner explosion-proof groove 33. The front side (facing the outside of the battery cell) of the cover body 3 is provided with an outer explosion-proof groove 32, and an explosion-proof engraved line 31 is provided at the center of the outer explosion-proof groove 32. The explosion-proof grooves are provided on both the front and back sides at the same time, which can effectively protect the explosion-proof engraved line 31 and prevent the explosion-proof engraved line 31 from being damaged by external forces encountered during the processing, transportation or use of the cover or battery. The explosion-proof groove can be set to be circular, semicircular or arc-shaped. The width of the explosion-proof groove can be adjusted according to the design, and can be set to 2mm, and the groove is circular.

[0053] The cover plate body 3 described in the present invention is made of common metal, such as any one of steel, iron, copper, aluminum, alloy and composite metal materials. Preferably, the thickness of the cover plate body 3 is set to 1.0 mm, and the cover plate diameter can be selected to be 18 mm.

[0054] like Figure 5As shown, the depth of the explosion-proof score line 31 is set to 1 / 5 to 2 / 3 of the thickness of the outer explosion-proof groove 32 and the inner explosion-proof groove 33. The cross-sectional shape of the explosion-proof score line 31 is an open "U" shape, and the opening angle range is 10° to 60°. The bottom end of the explosion-proof score line 31 is arc-shaped, and the arc radius setting range is between 0.01mm and 1mm.

[0055] The opening angle θ and arc radius R value selected by the present invention can be adjusted accordingly according to the actual design needs. The opening angle θ value of the second embodiment of the present invention is set to 45°, the arc radius R value is set to 0.05mm, and the depth of the line is set to 1 / 3 of the thickness of the groove. The U-shaped design of the explosion-proof line 31 can avoid the cracks caused by the original V-shaped sharp corners during the processing of the explosion-proof line 31, and improve the processing stability of the explosion-proof line 31. At the same time, the explosion-proof line 31 of the present invention can be set to arc, semicircle and circle.

[0056] The cross-section of the insulating sealing ring 2 is a right-angle "Z" shape, the height of the upper edge 21 of the insulating sealing ring is greater than the depth of the outer edge of the recessed groove on the cover plate, the upper end surface of the insulating sealing ring 2 is higher than the outer end surface of the cover plate body 3, and the height of the lower edge ring of the insulating sealing ring 2 is greater than the sum of the thickness of the central through hole 35 and the thickness of the lower insulating ring 4.

[0057] The insulating sealing ring 2 described in the present invention has a right-angle "Z"-shaped cross-section, and the upper edge height of the sealing ring needs to be greater than the depth of the outer edge of the recessed groove on the cover. That is, after assembly, the upper end surface of the insulating sealing ring 2 is higher than the outer end surface of the cover body 3, thereby ensuring the insulation effect between the central pole 1 and the cover body 3. The height H of the lower edge ring of the sealing ring is greater than the sum H' of the thickness of the central through hole 35 and the thickness of the lower insulating ring 4. It can be set to 1.2 to 1.8 times. In Example 2 of the present invention, H is set to 1.4 times H'.

[0058] The edge of the lower insulating ring 4 is provided with a lower insulating ring edge protrusion 43 toward the inner direction of the battery cell. The lower insulating ring edge protrusion 43 is wedge-shaped. The end face of the lower insulating ring edge protrusion 43 is lower than the end face position of the lower surface of the current collecting plate 6 after welding. At the same time, the inner diameter of the lower insulating ring edge protrusion 43 is larger than the diameter of the current collecting plate 6. The lower insulating ring 4 is also provided with a lower insulating ring center through hole 41. The diameter of the lower insulating ring center through hole 41 is larger than the lower end diameter of the central pole 1. Figure 6 As shown, there is a buffer gap 7 between the edge of the central through hole 41 of the lower insulating ring and the central pole 1 , and a circle of exhaust holes 42 are arranged at the edge of the lower insulating ring 4 , and the positions of the exhaust holes 42 are connected to the inner explosion-proof groove 33 .

[0059] The main feature of the lower insulating ring 4 described in the present invention is that a wedge-shaped protrusion is set on the edge of the insulating ring toward the inside of the battery cell, and the end face of the protrusion is lower than the end face position of the lower surface of the collector plate 6 after welding. At the same time, the inner diameter of the protrusion is larger than the diameter of the collector plate 6, ensuring that after the collector plate 6 and the central pole 1 are welded, there is a gap between the edge of the collector plate 6 and the inner edge of the insulating ring protrusion. This gap can generally be set to 0.2-1mm. In this embodiment 2, this gap is set to 0.4mm. At the same time, the outer diameter of the protrusion of the lower insulating ring 4 is smaller than the inner diameter of the careful shell, ensuring that there is a gap between the outer edge of the protrusion and the shell. The gap can generally be set to 0.2-1mm. In the embodiment 2 of the present invention, the gap between the outer edge of the protrusion of the embodiment 2 of the present invention and the shell is set to 0.4mm. At the same time, the diameter of the central through hole 41 of the lower insulating ring is larger than the lower end diameter of the central pole 1. After assembly, there is a buffer gap 7 between the edge of the central hole of the insulating ring and the central pole 1. At the same time, exhaust holes 42 are provided on the lower insulating ring 4, and the position of the exhaust holes 42 needs to be connected with the inner explosion-proof groove 33. The exhaust holes 42 can be set to any geometric shape, and the number can also be freely set according to design requirements. The present invention can select rhombus as the exhaust holes 42, the number is 16, and the exhaust holes 42 are evenly spaced. After the assembly is completed, the exhaust holes 42 are connected with the inner explosion-proof groove 33, thereby ensuring that when the pressure inside the battery cell is too high, the pressure of the gas can be smoothly transmitted to the explosion-proof groove, thereby further triggering the explosion threshold of the explosion-proof mark 31, and then smoothly releasing the pressure and exhausting the gas, thereby ensuring the safety of the battery cell during use.

[0060] The gasket 5 is in a circular ring shape, the size of the center hole of the gasket 5 matches the size of the lower end of the central pole 1 , and the outer diameter of the gasket 5 is smaller than the inner edge diameter of the exhaust hole 42 .

[0061] The main feature of the gasket 5 of the present invention is that it is annular, and the size of its center hole matches the size of the lower end of the central pole 1. The material is any one of common metals, such as steel, iron, copper, aluminum, alloy and composite metal materials, or other insulating materials. The outer diameter is smaller than the inner edge diameter of the exhaust hole 42.

[0062] It can be concluded from the above embodiments that the present invention proposes a new explosion-proof engraved line 31 design, which adopts a double-sided explosion-proof groove design to fully protect the stability of the explosion-proof engraved line 31, and effectively prevents the cover plate or battery from being damaged by external forces during processing, transportation or use. At the same time, the "U"-shaped explosion-proof engraved line 31 design can avoid the occurrence of cracks caused by the original V-shaped sharp corners during the processing of the explosion-proof engraved line 31, thereby improving the processing stability of the explosion-proof engraved line 31.

[0063] The cover plate structure proposed by the present invention simplifies the insulating plastic structure, combines the outer insulating ring and the insulating sealing ring 2 into one, and fully considers the deformation of the insulating rubber block. The cover plate body 3 is designed with a groove, a boss and a chamfered lower edge of the center hole. At the same time, a buffer gap 7 is set between the sealing ring and the lower insulating ring 4, and the deformation margin of the insulating rubber ring after assembly and extrusion is fully considered, which is conducive to the directional extrusion and extension of the insulating sealing ring 2. The gap and glue mass caused by uneven extrusion are avoided, and the sealing effect of the cover plate is greatly improved.

[0064] The cover plate structure proposed in the present invention is provided with an edge wedge-shaped protrusion and a buffer gap 7 of the inner ring in the design of the lower insulating ring 4, which effectively solves the insulation problem between the collector plate 6, the cover plate and the shell as a whole, and avoids the risk of internal short circuit. At the same time, in conjunction with the design of the internal explosion-proof groove 33, the exhaust hole 42 is designed to ensure that when the pressure inside the battery cell is too high, the pressure of the internal gas can be released in time, thereby ensuring the safety of the battery cell during use.

[0065] The above embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention.

Claims

1. A cover structure of a cylindrical battery, characterized in that: The invention comprises a central pole (1), wherein the lower part of the central pole (1) is electrically connected to a gasket (5) and a current collecting plate (6) in sequence, a cover plate body (3) is provided between the gasket (5) and the central collecting plate (1), an insulating sealing ring (2) is provided above the cover plate body (3), and a lower insulating ring (4) is provided at the lower end of the cover plate body (3).

2. The cover structure of a cylindrical battery according to claim 1, characterized in that: The material of the central pole (1) is metal, and the cross-sectional shape of the central pole (1) is a "T" shape.

3. The cover plate structure of a cylindrical battery according to claim 1, characterized in that: The cover plate body (3) has a circular structure and is provided with a central through hole (35) at its center. The cover plate body (3) is provided with a circular ring-shaped positioning recessed groove (34) radially outwardly along the central through hole (35), and the inner edge of the positioning recessed groove (34) is provided with a recessed groove inner edge protrusion (36).

4. The cover structure of a cylindrical battery according to claim 3, characterized in that: The height of the protrusion (36) on the inner edge of the groove is set between 0.01 mm and 0.5 mm, and the height of the protrusion (36) on the inner edge of the groove is less than the depth of the outer edge of the positioning groove (34).

5. The cover structure of a cylindrical battery according to claim 3, characterized in that: The lower edge of the central through hole (35) is provided with a central through hole lower edge chamfer (37).

6. A cover plate structure for a cylindrical battery according to claim 1 or 3, characterized in that: An inner explosion-proof groove (33) is provided on the back surface of the cover plate body (3), an outer explosion-proof groove (32) is provided on the front surface of the cover plate body (3), an explosion-proof engraved line (31) is provided at the center of the outer explosion-proof groove (32) of the cover plate body (3), and the inner explosion-proof groove (33) and the outer explosion-proof groove (32) are arc-shaped.

7. The cover structure of a cylindrical battery according to claim 6, characterized in that: The depth of the explosion-proof engraved line (31) is set to 1 / 5 to 2 / 3 of the thickness of the outer explosion-proof groove (32) and the inner explosion-proof groove (33). The cross-sectional shape of the explosion-proof engraved line (31) is an open "U" shape, and the opening angle range is 10° to 60°. The bottom end of the explosion-proof engraved line (31) is arc-shaped, and the arc radius is set in the range of 0.01mm to 1mm.

8. The cover structure of a cylindrical battery according to claim 1, characterized in that: The insulating sealing ring (2) has a right-angle "Z"-shaped cross section, the height of the upper edge (21) of the insulating sealing ring (2) is greater than the depth of the outer edge of the recessed groove on the cover plate, the upper end surface of the insulating sealing ring (2) is higher than the outer end surface of the cover plate body (3), and the height of the lower edge (22) of the insulating sealing ring is greater than the sum of the thickness of the central through hole (35) and the thickness of the lower insulating ring (4).

9. The cover structure of a cylindrical battery according to claim 8, characterized in that: The edge of the lower insulating ring (4) is provided with a lower insulating ring edge protrusion (43) facing the inside of the battery cell. The lower insulating ring edge protrusion (43) is wedge-shaped. The end face of the lower insulating ring edge protrusion (43) is lower than the end face position of the lower surface of the current collecting plate (6) after welding. At the same time, the inner diameter of the lower insulating ring edge protrusion (43) is larger than the diameter of the current collecting plate (6). The lower insulating ring (4) is also provided with a lower insulating ring central through hole (41). The diameter of the lower insulating ring central through hole (41) is larger than the lower end diameter of the central pole (1). A buffer gap (7) exists between the edge of the lower insulating ring central through hole (41) and the central pole (1). The edge of the lower insulating ring (4) is provided with a circle of a plurality of exhaust holes (42). The position of the exhaust holes (42) is connected to the inner explosion-proof groove (33).

10. The cover structure of a cylindrical battery according to claim 1, characterized in that: The gasket (5) is in the shape of a circular ring, the size of the center hole of the gasket (5) matches the size of the lower end of the central pole (1), and the outer diameter of the gasket (5) is smaller than the inner edge diameter of the exhaust hole (42).

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