An improved lithium battery end structure and manufacturing method

Abstract

The present invention discloses an improved lithium battery end structure and manufacturing method, which includes a shell, a battery cell, a current collecting sheet, a current collecting column, a sealing ring and a bottom cover, etc. The main feature is to add a set of isolation cover on the top of the current collecting column, and provide an upper folding edge with a circumference bent upward on the periphery of the isolation cover; at the same time, a lower folding edge with a circumference bent downward is provided on the periphery of the outer cover, and the lower folding edge is fitted inside the upper folding edge, and then a pressure ring is provided inside the upper folding edge to seal and fit between the lower folding edge and the outer circumference of the current collecting column. Obviously, the design of the above-mentioned lithium battery end structure is simpler and more convenient, especially the isolation cover with an upper folding edge design and the outer cover with a lower folding edge design. The unique design of the upper and lower folding edges can better take into account the excellent performance of the product at the same time, and it is combined with the corresponding manufacturing method to better meet the automated processing and manufacturing needs of the production equipment.

Description

Technical Field

[0001] The present invention relates to the manufacture of a lithium battery, and in particular to an improved lithium battery end structure and a manufacturing method. Background Art

[0002] At present, the manufacture of cylindrical lithium batteries requires sealing the ends of the outer shell to form the positive or negative terminal of the lithium battery. These end structures are very important for the design and production process of lithium batteries. They must not only meet the performance requirements of lithium batteries, but also meet the process requirements and the requirements of realizing the automation of production equipment. Although many existing designs of lithium battery end structures already have good structural characteristics, with the continuous increase in lithium battery applications and the continuous expansion of market demand, lithium battery manufacturers are also constantly conducting additional research and development to be able to launch more lithium batteries with different end structures, thereby taking into account the excellent performance of the product and meeting the automated processing and manufacturing needs of production equipment. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a lithium battery end structure and manufacturing method that can simultaneously take into account the excellent performance of the product and meet the needs of automated processing and manufacturing of production equipment.

[0004] The technical problem of the present invention is achieved through the following technical solutions:

[0005] An improved lithium battery end structure comprises an outer shell, a battery cell in the outer shell, and a current collecting sheet installed at the end of the outer shell and enclosing the battery cell; a bottom cover is provided on the outside of the current collecting sheet, a sealing cover is provided between the current collecting sheet and the bottom cover, a current collecting column is provided on the current collecting sheet, and the battery cell, the current collecting sheet and the current collecting column form a conductive structure; a welding hole and a sealing plug are provided in the current collecting column, and the top of the current collecting column passes through the sealing cover and the bottom cover in sequence and then an outer cover is installed, the outer cover and the current collecting column form a conductive structure, and the sealing plug is sealed in the welding hole, an insulating cover is installed on the top of the current collecting column, and an upper folding edge with a circumference bent upward is provided on the outer periphery of the insulating cover; a lower folding edge with a circumference bent downward and fitted in the upper folding edge is provided on the outer periphery of the outer cover; a pressure ring is provided in the upper folding edge and is sealed and fitted between the lower folding edge and the outer circumference of the current collecting column.

[0006] The bottom of the current collecting column is provided with a sleeved and fixed retaining ring, which is fitted between the current collecting sheet and the sealing cover. The middle of the current collecting column is provided with an outer shoulder that abuts against the retaining ring.

[0007] The outer circumference of the current collecting piece is provided with a flange that is folded upwards in the circumference, an insulating ring is provided between the flange and the shell, and the insulating ring is provided with a circumferential edge that wraps around the flange.

[0008] The sealing cover is provided with a sealing hole for the top of the current collecting column to pass through, and the bottom cover is provided with a cover hole for the top of the current collecting column to pass through. The inner circumference of the sealing hole is provided with a sealing edge extending circumferentially upward. The sealing edge passes through the cover hole and seals in contact with the insulating cover, and forms a seal between the bottom cover and the current collecting column, or the sealing edge passes through the cover hole and the insulating cover in sequence and seals in contact with the pressure ring, and forms a seal between the bottom cover, the insulating cover and the current collecting column.

[0009] The sealing plug is installed in the welding hole through the sealing ring on the outer circumference.

[0010] The sealing plug is a solid cylindrical block or a hollow cylindrical block with an H-shaped cross section.

[0011] The current collecting sheet is provided with a current collecting hole, the bottom of the current collecting column is provided with a bottom hole respectively connected to the current collecting hole and the welding hole, and the outer cover is provided with a top hole.

[0012] An explosion-proof valve is arranged in the sealing plug.

[0013] The bottom cover is fitted into the end of the shell, and the outer circumference of the bottom cover is pressed tightly by the curling edge of the shell end to form a connection, or the bottom cover is directly formed by bending the circumference of the shell end.

[0014] A method for manufacturing an improved lithium battery end structure comprises the following steps:

[0015] Step 1: Prepare and prepare the outer shell, battery cell, current collector, insulating ring, current collecting column, retaining ring, sealing cover, bottom cover, insulating cover, outer cover, sealing plug and pressing ring that constitute the lithium battery. The outer shell and bottom cover adopt two structural methods: the first is that the bottom cover fits into the end of the outer shell, and the outer circumference of the bottom cover is pressed tightly by the curling edge of the end of the outer shell to form a connection; the second is that the bottom cover is directly bent by the circumference of the end of the outer shell;

[0016] Step 2: If the shell and bottom cover adopt the first structure,

[0017] ① The battery cell is placed in the shell, and the current collector is sealed at the end of the shell through an insulating ring. The current collector is welded to the tab of the battery cell, and the insulating ring is fixed by the rolling groove on the outer circumference of the shell.

[0018] ② The bottom cover and the sealing cover are assembled as one, that is, the bottom cover is embedded in the embedding groove formed by the folding of the outer circumference of the sealing cover, and the sealing edge of the central sealing hole of the sealing cover must also be inserted into the cover hole of the bottom cover;

[0019] ③ Install the current collecting column on the current collecting sheet, and weld the current collecting column and the retaining ring together in advance. Then install the bottom cover and sealing cover that have been assembled on the current collecting sheet, and make the top of the current collecting column pass through the sealing hole of the sealing cover and the cover hole of the bottom cover in sequence. At the same time, the retaining ring is installed in the installation space formed by the bending of the sealing cover.

[0020] ④ The outer circumferences of the bottom cover and the sealing cover are pressed tightly by the curling edge of the shell end to form a connection, and the sealing edge inserted into the cover hole just forms a seal between the bottom cover and the collecting column;

[0021] ⑤ An insulating cover and a pressure ring are installed on the top of the current collecting column that passes through the sealing cover and the bottom cover in sequence, and the sealing edge inserted into the cover hole is sealed in contact with the insulating cover, and the pressure ring is welded to the current collecting column;

[0022] ⑥ First, weld the current collecting column and the current collecting sheet through the welding hole of the current collecting column, then inject the electrolyte into the shell through the bottom hole at the bottom of the current collecting column and the current collecting hole on the current collecting sheet, and then seal the sealing plug with the explosion-proof valve into the welding hole of the current collecting column, and weld the sealing plug to the current collecting column;

[0023] ⑦ A welded outer cover is installed on the top of the current collecting column, and the outer cover seals the sealing plug in the welding hole. The lower fold of the outer cover fits in the upper fold of the insulating cover, and the pressing ring is squeezed to form a seal between the lower fold of the outer cover and the outer circumference of the current collecting column;

[0024] If the shell and bottom cover adopt the second structure, then

[0025] ① First, assemble the current collector and the insulating ring into one piece, then install it on the battery cell, and fix the current collector to the tab of the battery cell by welding;

[0026] ②Install the sealing cover into the housing with the bottom cover, and insert the sealing edge of the central sealing hole of the sealing cover into the cover hole of the bottom cover;

[0027] ③ First, weld the collecting column and the retaining ring together in advance, then pass the top of the collecting column through the sealing hole of the sealing cover and the cover hole of the bottom cover in sequence, and at the same time, the retaining ring is just installed in the installation space formed by the bending of the sealing cover;

[0028] ④ An insulating cover and a pressure ring are installed on the top of the current collecting column that passes through the sealing cover and the bottom cover in sequence, and the sealing edge inserted into the cover hole passes through the cover hole and then passes through the insulating cover to seal and contact the pressure ring, so as to form a seal between the bottom cover, the insulating cover and the current collecting column, and the pressure ring and the current collecting column are welded;

[0029] ⑤ Insert the assembled current collector, insulation ring and battery cell into the outer shell;

[0030] ⑥ First, weld the current collecting column and the current collecting sheet through the welding hole of the current collecting column, then inject the electrolyte into the shell through the bottom hole at the bottom of the current collecting column and the current collecting hole on the current collecting sheet, and then seal the sealing plug with the explosion-proof valve into the welding hole of the current collecting column, and weld the sealing plug to the current collecting column;

[0031] ⑦ A welded outer cover is installed on the top of the current collecting column, and the outer cover seals the sealing plug in the welding hole. The lower folded edge of the outer cover is fitted in the upper folded edge of the insulating cover, and the pressure ring is squeezed to form a seal between the lower folded edge of the outer cover and the outer circumference of the current collecting column.

[0032] Compared to the existing technology, the present invention primarily incorporates a fitted insulating cover on top of the current collecting column, with an upper folded edge curved upward around the outer periphery of the insulating cover. Simultaneously, a lower folded edge curved downward around the outer periphery of the cover is fitted within the upper folded edge, and a pressure ring is further provided within the upper folded edge to seal the lower folded edge against the outer periphery of the current collecting column. Clearly, the design of this lithium battery end structure is simpler and more convenient, while simultaneously ensuring excellent product performance and meeting the automated processing and manufacturing requirements of production equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic cross-sectional view of the first end structure of the present invention.

[0034] Figure 2 for Figure 1 Stereoscopic image.

[0035] Figure 3 This is a schematic cross-sectional view of the second end structure of the present invention.

[0036] Figure 4 It is a schematic diagram of the cross-sectional structure of the collecting column and the retaining ring.

[0037] Figure 5 Schematic diagram of the cross-sectional structure of the outer cover.

[0038] Figure 6 It is a schematic diagram of the cross-sectional structure of the insulation cover.

[0039] Figure 7 It is a schematic diagram of the cross-sectional structure of the end structure suitable for the one-piece bottom cover.

[0040] Figure 8 This is the first closed structure of the current collecting plate at the end of the shell.

[0041] Figure 9 This is the second closed structure of the current collecting plate at the end of the shell.

[0042] Figure 10 for Figure 1 、 Figure 3Cross-sectional view of the sealing structure of the first sealing edge.

[0043] Figure 11 for Figure 7 Cross-sectional view of the sealing structure of the second sealing edge.

[0044] Figure 12 for Figure 1 Schematic diagram of the structure of the midsole cover.

[0045] Figure 13 for Figure 1 Schematic diagram of the structure of the middle sealing cover. DETAILED DESCRIPTION

[0046] The embodiments of the present invention will be described in detail below with reference to the above-mentioned drawings.

[0047] like Figures 1 to 13 As shown, 1. shell, 11. curling, 12. rolling groove, 13. insulating ring, 131. edging, 2. battery cell, 3. current collecting sheet, 31. current collecting hole, 32. flange, 4. bottom cover, 41. cover hole, 5. sealing cover, 51. sealing hole, 511. sealing edge, 52. embedding groove, 6. current collecting column, 61. welding hole, 62. bottom hole, 63. outer shoulder, 7. insulating cover, 71. upper folding edge, 8. outer cover, 81. lower folding edge, 82. top hole, 9. sealing plug, 91. sealing ring, 92. retaining ring, 93. explosion-proof valve, 10. pressing ring, etc.

[0048] An improved lithium battery end structure and manufacturing method, such as Figure 1 、 Figure 3 As shown, it mainly involves the manufacture of the end seal of a cylindrical lithium battery, which includes a metal cylindrical shell 1, a battery cell 2 arranged in the shell, and a current collector 3 installed at the end of the shell and sealing the battery cell 2.

[0049] The closed structure of the current collecting piece 3 at the end of the housing 1 is as follows Figure 8 、 Figure 9 As shown, it mainly refers to the outer circumference of the current collecting piece 3 is provided with a flange 32 that is folded upward, and an insulating ring 13 is provided between the flange and the shell 1, and the insulating ring is provided with Figure 1 、 Figure 3 or Figure 7 The circumference shown wraps around the edge 131 of the flange 32, thereby ensuring structural compactness and insulation between the two.

[0050] The collector plate 3 is provided with a bottom cover 4, and a sealing cover 5 is provided between the collector plate 3 and the bottom cover 4 for spacing. Figure 1As shown, a sealing cover 5 and a bottom cover 4 are sequentially provided on the current collecting sheet 3, and the bottom cover 4 is just embedded in the embedding groove 52 formed by folding the outer circumference of the sealing cover 5. A current collecting post 6 is also provided on the current collecting sheet 3. The battery cell 2, the current collecting sheet 3 and the current collecting post 6 form a conductive structure to draw out current.

[0051] The current collecting column 6 is provided with a welding hole 64 and a sealing plug 9 installed in the welding hole 64. Specifically, the sealing plug is installed in the welding hole 61 through the sealing ring 94 on the outer circumference. The top of the current collecting column 6 passes through the sealing cover 5 and the bottom cover 4 in sequence and then the outer cover 8 is installed. The outer cover forms conductivity with the current collecting column 6 and seals the sealing plug 9 in the welding hole 61.

[0052] At the same time, the top of the collecting column 6 is provided with an insulating cover 7. In fact, the top of the collecting column 6 passes through the sealing cover 5, the bottom cover 4 and the insulating cover 7 in sequence before the outer cover 8 is installed. The outer periphery of the insulating cover 7 is provided with Figure 6 The upper folding edge 71 is bent upwards, that is, the insulating cover 7 is combined with the upper folding edge 71 to form a cover-shaped component that is open upwards; and the outer cover 8 is provided with a Figure 5 The lower folded edge 81 is bent downwardly on the circumference shown, that is, the outer cover 8 combined with the lower folded edge 81 just forms a cover-like component that is open downward, and the lower folded edge 81 is completely fitted in the upper folded edge 71, and then a pressure ring 10 is also provided in the upper folded edge to seal between the lower folded edge 81 and the outer circumference of the collecting column 6.

[0053] At this time, the lower folded edge 81 of the outer circumference of the outer cover 8 can be separated from the bottom cover 4 by the insulating cover 7 to prevent contact short circuit, and can also form a sealed fit with the outer circumference of the collecting column 6 through the pressure ring 10.

[0054] The sealing cover 5 is provided with a sealing hole 51 for the top of the collecting column 6 to pass through, and the bottom cover 4 is provided with a cover hole 41 for the top of the collecting column 6 to pass through. The inner circumference of the sealing hole 51 is provided with a sealing edge 511 extending upwardly. The sealing edge has two sealing structures. The first one is as follows: Figure 10 As shown in FIG, after passing through the cover hole 41, the seal is tightly contacted on the insulating cover 7, thereby forming a seal between the bottom cover 4 and the current collecting column 6. Figure 11 As shown, after passing through the cover hole 41, it passes through the insulating cover 7 and is sealed and tightly contacted on the pressure ring 10 to form a seal between the bottom cover 4, the insulating cover 7 and the collecting column 6, and the sealing edge 511 passing through the cover hole 41 also slightly wraps around the bottom cover 4 in the opposite direction, thereby improving the sealing and compactness of the structure.

[0055] The bottom of the collecting column 6 is provided with Figure 4The retaining ring 92 shown is made of the same material as the collecting column 6, and an outer shoulder 63 is provided in the middle of the collecting column 6 to support the retaining ring 92, and is welded and fixed to the retaining ring 92 through the outer shoulder; at the same time, the retaining ring 92 is installed between the collecting plate 3 and the sealing cover 5, and is actually embedded in the installation space formed by the bending of the sealing cover 5.

[0056] There are two main purposes for designing this split welded fixed current collecting column 6 and retaining ring 92: one is that the split current collecting column 6 and retaining ring 92 are easy to process, that is, it is simpler and more convenient to process the two parts separately and then weld them together; the other is that the retaining ring 92 is used to increase the contact area between the current collecting column 6 and the current collecting sheet 3, and other components such as the sealing cover 5, the bottom cover 4, the insulating cover 7, etc. can be pressed on the retaining ring 92, so as to ensure the compactness and stability of the installation structure of the current collecting column 6, and prevent the internal pressure of the shell 1 from breaking open the current collecting column 6.

[0057] The sealing plug 9 is a Figure 1 、 Figure 2 Solid cylindrical blocks as shown or Figure 3 The cross section of the hollow cylindrical block is H-shaped. If the cross section of the hollow cylindrical block is H-shaped, the collecting hole 31 needs to be provided on the collecting plate 3, and the bottom of the collecting column 6 needs to be provided with a Figure 4 As shown, bottom hole 62, which connects to manifold 31 and welding hole 61, must be provided with a top hole 82 on outer cover 8. Furthermore, an explosion-proof valve 93, specifically an H-shaped one, must be located in the center of sealing plug 9, facing bottom hole 62, to provide safety protection. If sealing plug 9 is a solid cylindrical block, top hole 82 is not required on outer cover 8.

[0058] In addition, the end structure of the present invention can be applied to two types of bottom cover 4 structures, one of which is as follows: Figures 1 to 3 The bottom cover structure shown is a split type, that is, the bottom cover 4 as a separate component fits in the end of the shell 1, and the outer circumference of the bottom cover 4 is pressed tightly by the curling edge 11 at the end of the shell 1 to form a connection. The outer circumference of the shell 1 is also provided with a rolling groove 12 to press the outer periphery of the current collecting plate 3, that is, to press and fix the insulating ring 13; another type is as follows Figure 7 The bottom cover structure shown is a one-piece structure, that is, the bottom cover 4 is directly formed by bending the end of the outer shell 1 into a one-piece circle.

[0059] Obviously, the design of the above-mentioned lithium battery end structure is simpler and more convenient, especially the insulating cover 7 designed with an upper folding edge 71 and the outer cover 8 designed with a lower folding edge 81. The unique design of the upper and lower folding edges can better take into account the excellent performance of the product and meet the needs of automated processing and manufacturing of production equipment.

[0060] The manufacturing method of the improved lithium battery end structure mainly includes the following steps:

[0061] Step 1: Prepare and set aside the outer shell 1, battery cell 2, current collector 3, insulating ring 13, current collecting column 6, retaining ring 92, sealing cover 5, bottom cover 4, insulating cover 7, outer cover 8, sealing plug 9 and pressing ring 10 that constitute the lithium battery. The outer shell 1 and the bottom cover 4 adopt two structural methods: the first is that the bottom cover 4 fits in the end of the outer shell 1, and the outer circumference of the bottom cover 4 is pressed by the curling edge 11 of the end of the outer shell 1 to form a connection; the second is that the bottom cover 4 is directly formed by bending the circumference of the end of the outer shell 1;

[0062] Step 2: If the housing 1 and the bottom cover 4 adopt the first structural mode, then

[0063] ① The battery cell 2 is installed in the housing 1, and the current collector 3 is sealed and arranged at the end of the housing 1 through the insulating ring 13. The current collector 3 is welded to the tab of the battery cell 2, and the insulating ring 13 is pressed and deformed inward by the rolling groove 12 on the outer circumference of the housing 1;

[0064] ② The bottom cover 4 and the sealing cover 5 are assembled as one body, that is, the bottom cover 4 is embedded in the embedding groove 52 formed by the folding of the outer circumference of the sealing cover 5, and the sealing edge 511 at the central sealing hole 51 of the sealing cover 5 must also be inserted into the cover hole 41 of the bottom cover 4;

[0065] ③ Install the current collecting column 6 on the current collecting plate 3. The current collecting column 6 and the retaining ring 92 must be welded together in advance. Then install the bottom cover 4 and the sealing cover 5 that have been assembled together on the current collecting plate 3. Make the top of the current collecting column 6 pass through the sealing hole 51 of the sealing cover 5 and the cover hole 41 of the bottom cover 4 in sequence. At the same time, the retaining ring 92 is exactly installed in the installation space formed by the bending of the sealing cover 5.

[0066] ④ The outer circumferences of the bottom cover 4 and the sealing cover 5 are pressed together by the curling edge 11 at the end of the housing 1, and the sealing edge 511 inserted into the cover hole 41 forms a seal between the bottom cover 4 and the collecting column 6;

[0067] ⑤ The top of the current collecting column 6 passing through the sealing cover 5 and the bottom cover 4 is covered with an insulating cover 7 and a pressing ring 10, and the sealing edge 511 inserted into the cover hole 41 is sealed and in contact with the insulating cover 7, and the pressing ring 10 is welded to the current collecting column 6;

[0068] ⑥ First, weld the current collecting post 6 and the current collecting sheet 3 together through the welding hole 61 of the current collecting post 6. Then, inject electrolyte into the housing 1 through the bottom hole 62 at the bottom of the current collecting post 6 and the current collecting hole 31 on the current collecting sheet 3. Then, seal the sealing plug 9 with the explosion-proof valve 93 into the welding hole 61 of the current collecting post 6. The sealing plug 9 and the current collecting post 6 are welded together.

[0069] ⑦ The top of the current collecting column 6 is installed with a welded outer cover 8, and the outer cover seals the sealing plug 9 in the welding hole 61. The lower folded edge 81 of the outer cover 8 is fitted into the upper folded edge 71 of the insulating cover 7, and the pressing ring 10 is squeezed to form a seal between the lower folded edge 81 of the outer cover 8 and the outer circumference of the current collecting column 6;

[0070] If the housing 1 and the bottom cover 4 adopt the second structural mode, then

[0071] ① First, assemble the current collector 3 and the insulating ring 13 into one piece, then install them on the battery cell 2, and fix the current collector 3 to the tabs of the battery cell 2 by welding;

[0072] ② Install the sealing cover 5 into the housing 1 with the bottom cover 4, and insert the sealing edge 511 at the central sealing hole 51 of the sealing cover 5 into the cover hole 41 of the bottom cover 4;

[0073] ③ First, weld the collecting column 6 and the retaining ring 92 together in advance, then pass the top of the collecting column 6 through the sealing hole 51 of the sealing cover 5 and the cover hole 41 of the bottom cover 4 in sequence, and at the same time, the retaining ring 92 is exactly fitted into the installation space formed by the bending of the sealing cover 5;

[0074] ④ The top of the current collecting column 6 passing through the sealing cover 5 and the bottom cover 4 in sequence is covered with an insulating cover 7 and a pressing ring 10, and the sealing edge 511 inserted into the cover hole 41 is passed through the cover hole 41 and then passes through the insulating cover 7 to seal and contact the pressing ring 10, so as to form a seal between the bottom cover 4, the insulating cover 7 and the current collecting column 6, and the pressing ring 10 is welded to the current collecting column 6;

[0075] ⑤ Insert the assembled current collector 3, insulating ring 13 and battery cell 2 into the housing 1;

[0076] ⑥ First, weld the current collecting post 6 and the current collecting sheet 3 together through the welding hole 61 of the current collecting post 6. Then, inject electrolyte into the housing 1 through the bottom hole 62 at the bottom of the current collecting post 6 and the current collecting hole 31 on the current collecting sheet 3. Then, seal the sealing plug 9 with the explosion-proof valve 93 into the welding hole 61 of the current collecting post 6. The sealing plug 9 and the current collecting post 6 are welded together.

[0077] ⑦ An outer cover 8 is installed on the top of the current collecting column 6 and is fixed by welding. The outer cover seals the sealing plug 9 in the welding hole 61. The lower folded edge 81 of the outer cover 8 is fitted in the upper folded edge 71 of the insulating cover 7, and the pressure ring 10 is squeezed to form a seal between the lower folded edge 81 of the outer cover 8 and the outer circumference of the current collecting column 6.

[0078] The above description is only a specific embodiment of the present invention. Those skilled in the art should understand that any structural design similar to this embodiment should be included in the protection scope of the present invention.

Claims

1. An improved lithium battery end structure, comprising a shell (1), a battery cell (2) in the shell, and a current collecting sheet (3) installed at the end of the shell and enclosing the battery cell (2); a bottom cover (4) is provided outside the current collecting sheet, a sealing cover (5) is provided between the current collecting sheet (3) and the bottom cover (4), a current collecting column (6) is provided on the current collecting sheet (3), and the battery cell (2), the current collecting sheet (3) and the current collecting column (6) form a conductive structure; a welding hole (61) and a sealing plug (9) inserted in the welding hole (61) are provided in the current collecting column (6), the top of the current collecting column (6) passes through the sealing cover (5) and the bottom cover (4) in sequence, and then an outer cover (8) is installed, the outer cover and the current collecting column (6) form a conductive structure, and the sealing plug (9) is sealed and covered in the welding hole (61), characterized in that The top of the current collecting column (6) is provided with an insulating cover (7), and the outer periphery of the insulating cover is provided with an upper folding edge (71) with a circumference bent upward; the outer periphery of the outer cover (8) is provided with a lower folding edge (81) with a circumference bent downward and fitted in the upper folding edge (71); the upper folding edge (71) is provided with a pressure ring (10) that is sealed and fitted between the lower folding edge (81) and the outer circumference of the current collecting column (6); the bottom of the current collecting column (6) is provided with a fixed retaining ring (92), which is fitted between the current collecting sheet (3) and the sealing cover (5), and the middle of the current collecting column (6) is provided with an outer shoulder (63) that abuts against the retaining ring (92); the sealing cover (5) is provided with a sealing hole (51) for the top of the current collecting column (6) to pass through, and the bottom cover (4) is provided with a cover hole (41) for the top of the current collecting column (6) to pass through. The inner circumference of the sealing hole (51) is provided with a sealing edge (511) extending circumferentially upward, and the sealing edge passes through the cover hole (41) and is in sealing contact with the insulating cover (7), thereby forming a seal between the bottom cover (4) and the current collecting column (6), or the sealing edge (511) passes through the cover hole (41) and the insulating cover (7) in sequence and is in sealing contact with the pressure ring (10), thereby forming a seal between the bottom cover (4), the insulating cover (7) and the current collecting column (6).

2. The improved lithium battery end structure according to claim 1, characterized in that The outer circumference of the current collecting piece (3) is provided with a flange (32) that is folded upwards in the circumference, an insulating ring (13) is provided between the flange and the housing (1), and the insulating ring is provided with a wrapping edge (131) that wraps around the flange (32).

3. The improved lithium battery end structure according to claim 1, characterized in that The sealing plug (9) is installed in the welding hole (61) through the sealing ring (91) on the outer circumference.

4. The improved lithium battery end structure according to claim 1, characterized in that The sealing plug (9) is a solid cylindrical block or a hollow cylindrical block with an H-shaped cross section.

5. The improved lithium battery end structure according to claim 4, characterized in that The current collecting plate (3) is provided with a current collecting hole (31), the bottom of the current collecting column (6) is provided with a bottom hole (62) respectively connected to the current collecting hole (31) and the welding hole (61), and the outer cover (8) is provided with a top hole (82).

6. The improved lithium battery end structure according to claim 1, characterized in that An explosion-proof valve (93) is provided in the sealing plug (9).

7. The improved lithium battery end structure according to claim 1, characterized in that The bottom cover (4) is fitted into the end of the outer shell (1), and the outer circumference of the bottom cover (4) is pressed by the curling edge (11) at the end of the outer shell (1) to form a connection, or the bottom cover (4) is directly formed by bending the circumference of the end of the outer shell (1).

8. The method for manufacturing an improved lithium battery end structure according to claim 1, characterized in that The manufacturing method comprises the following steps: Step 1: Prepare and prepare the outer shell (1), battery cell (2), current collecting sheet (3), insulating ring (13), current collecting column (6), retaining ring (92), sealing cover (5), bottom cover (4), insulating cover (7), outer cover (8), sealing plug (9) and pressing ring (10) constituting the lithium battery, wherein the outer shell (1) and the bottom cover (4) adopt two structural modes: the first mode is that the bottom cover (4) is fitted into the end of the outer shell (1), and the outer circumference of the bottom cover (4) is pressed by the curling edge (11) of the end of the outer shell (1) to form a connection; the second mode is that the bottom cover (4) is directly formed by bending the circumference of the end of the outer shell (1); Step 2: If the housing (1) and the bottom cover (4) adopt the first structural method, then ① The battery cell (2) is installed in the housing (1), the current collecting sheet (3) is sealed and arranged at the end of the housing (1) through the insulating ring (13), the current collecting sheet (3) is welded and fixed to the tab of the battery cell (2), and the insulating ring (13) is pressed and deformed inward by the rolling groove (12) on the outer circumference of the housing (1); ② The bottom cover (4) and the sealing cover (5) are assembled as one body, that is, the bottom cover (4) is embedded in the embedding groove (52) formed by folding the outer circumference of the sealing cover (5), and the sealing edge (511) at the central sealing hole (51) of the sealing cover (5) also needs to be inserted into the cover hole (41) of the bottom cover (4); ③ Install the current collecting column (6) on the current collecting sheet (3), and the current collecting column (6) and the retaining ring (92) need to be welded and fixed into one piece in advance, then install the bottom cover (4) and the sealing cover (5) that have been assembled into one piece on the current collecting sheet (3), and make the top of the current collecting column (6) pass through the sealing hole (51) of the sealing cover (5) and the cover hole (41) of the bottom cover (4) in sequence, and at the same time, the retaining ring (92) is just installed in the installation space formed by bending the sealing cover (5); ④ The outer circumferences of the bottom cover (4) and the sealing cover (5) are pressed together by the curling edge (11) at the end of the housing (1), and the sealing edge (511) inserted into the cover hole (41) forms a seal between the bottom cover (4) and the collecting column (6); ⑤ The top of the current collecting column (6) passing through the sealing cover (5) and the bottom cover (4) is covered with an insulating cover (7) and a pressing ring (10), and the sealing edge (511) inserted into the cover hole (41) is sealed and contacted with the insulating cover (7), and the pressing ring (10) and the current collecting column (6) are welded; ⑥ First, the current collecting column (6) and the current collecting sheet (3) are welded and fixed through the welding hole (61) of the current collecting column (6), and then the electrolyte is injected into the housing (1) through the bottom hole (62) at the bottom of the current collecting column (6) and the current collecting hole (31) on the current collecting sheet (3), and then the sealing plug (9) with the explosion-proof valve (93) is sealed and installed in the welding hole (61) of the current collecting column (6), and the sealing plug (9) and the current collecting column (6) are welded; ⑦ The top of the current collecting column (6) is equipped with a welded outer cover (8), and the outer cover seals the sealing plug (9) in the welding hole (61). The lower folding edge (81) of the outer cover (8) is fitted in the upper folding edge (71) of the insulating cover (7), and the pressing ring (10) is squeezed to form a seal between the lower folding edge (81) of the outer cover (8) and the outer circumference of the current collecting column (6); If the housing (1) and the bottom cover (4) adopt the second structural mode, then ① First, assemble the current collector (3) and the insulating ring (13) into one piece, then install them on the battery cell (2), and fix the current collector (3) and the tab of the battery cell (2) by welding; ② Install the sealing cover (5) into the housing (1) with the bottom cover (4), and insert the sealing edge (511) at the central sealing hole (51) of the sealing cover (5) into the cover hole (41) of the bottom cover (4); ③ First, weld the collecting column (6) and the retaining ring (92) together in advance, then pass the top of the collecting column (6) through the sealing hole (51) of the sealing cover (5) and the cover hole (41) of the bottom cover (4) in sequence, and at the same time, the retaining ring (92) is just fitted into the installation space formed by bending the sealing cover (5); ④ The top of the current collecting column (6) passing through the sealing cover (5) and the bottom cover (4) is covered with an insulating cover (7) and a pressing ring (10), and the sealing edge (511) inserted into the cover hole (41) is passed through the cover hole (41) and then passes through the insulating cover (7) to seal and contact the pressing ring (10), so as to form a seal between the bottom cover (4), the insulating cover (7) and the current collecting column (6), and the pressing ring (10) and the current collecting column (6) are welded; ⑤ Insert the integrated current collector (3), insulating ring (13) and battery cell (2) into the housing (1); ⑥ First, the current collecting column (6) and the current collecting sheet (3) are welded and fixed through the welding hole (61) of the current collecting column (6), and then the electrolyte is injected into the housing (1) through the bottom hole (62) at the bottom of the current collecting column (6) and the current collecting hole (31) on the current collecting sheet (3), and then the sealing plug (9) with the explosion-proof valve (93) is sealed and installed in the welding hole (61) of the current collecting column (6), and the sealing plug (9) and the current collecting column (6) are welded; ⑦ A welded outer cover (8) is installed on the top of the current collecting column (6), and the outer cover seals the sealing plug (9) in the welding hole (61). The lower folding edge (81) of the outer cover (8) is fitted in the upper folding edge (71) of the insulating cover (7), and the pressing ring (10) is squeezed to form a seal between the lower folding edge (81) of the outer cover (8) and the outer circumference of the current collecting column (6).

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