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CN-224232881-U - Negative electrode current collecting disc welding assembly and cylindrical lithium ion battery

CN224232881UCN 224232881 UCN224232881 UCN 224232881UCN-224232881-U

Abstract

The utility model relates to the technical field of cylindrical batteries, and provides a welding assembly of a negative current collecting disc and a cylindrical lithium ion battery, wherein the welding assembly comprises the negative current collecting disc and a plurality of welding marks arranged on the negative current collecting disc, the welding marks are used for welding and fixing the negative current collecting disc and a rolling core negative side rolling flat layer, a welding track of the negative current collecting disc and the rolling core negative side rolling flat layer is the welding marks, a region fixedly connected with the rolling core negative side rolling flat layer through one welding mark on the negative current collecting disc is a welding surface, the area of the negative current collecting disc is S 0 , and the area of each welding surface is S 1 , wherein 3% of S 0 ≤S 1 ≤5％S 0 . According to the utility model, the welding marks are arranged on the negative electrode current collecting disc, and the welding areas are limited, so that the welding reliability of the negative electrode current collecting disc and the winding core can be improved, the internal resistance of the battery can be optimized, the overcurrent capacity at the welding positions can be enhanced, and the overall performance of the battery can be ensured.

Inventors

  • ZHANG YE
  • LI YANG
  • Wang Chitang

Assignees

  • 江苏睿恩新能源科技有限公司

Dates

Publication Date
20260512
Application Date
20250425

Claims (10)

  1. 1. The welding component of the negative electrode current collecting disc is characterized by comprising a negative electrode current collecting disc (1) and a plurality of welding marks (2) positioned on the negative electrode current collecting disc (1); The welding mark (2) is used for welding and fixing the negative electrode current collecting disc (1) and the rolling core negative electrode side rolling layer, a welding track of the negative electrode current collecting disc (1) and the rolling core negative electrode side rolling layer is the welding mark (2), and a welding surface (101) is a region on the negative electrode current collecting disc (1) fixedly connected with the rolling core negative electrode side rolling layer through one welding mark (2); The area of the negative electrode current collecting disc (1) is S 0 , and the area of each welding surface (101) is S 1 , wherein 3% of S 0 ≤S 1 ≤5％S 0 .
  2. 2. A negative current collecting plate welding assembly according to claim 1, wherein the sum of the areas of a plurality of said welding surfaces (101) is S 10 , wherein 10% S 0 ≤S 10 ≤20％S 0 .
  3. 3. The welding assembly for the anode current collecting plate according to claim 1, further comprising a boss (3), wherein the boss (3) is fixedly arranged on the anode current collecting plate (1) and used for being welded and fixed with a shell bottom, and the area of the boss (3) is S 2 , wherein 5%S 0 ≤S 2 ≤15％S 0 is arranged.
  4. 4. The welding assembly of the negative current collecting plate according to claim 1, wherein the welding stamp (2) comprises a plurality of welding wires (21), the welding wires (21) are wavy, and the plurality of welding wires (21) are arranged at intervals; The welding surface (101) is rectangular, the length of the welding surface (101) is L 1 , and the width of the welding surface (101) is W 1 , wherein L 1 is more than or equal to 3.5mm and less than or equal to 5.5mm, and W 1 is more than or equal to 1.6mm and less than or equal to 3.4mm.
  5. 5. A welding assembly for a negative electrode collector plate according to claim 3, wherein said negative electrode collector plate (1) and said boss (3) are both circular; The radius of the negative electrode current collecting disc (1) is R 0 , the radius of the boss (3) is R 1 , wherein R 0 is more than or equal to 8.5mm and less than or equal to 10.5mm, and R 1 is more than or equal to 2mm and less than or equal to 4mm.
  6. 6. A negative current collecting plate welding assembly according to claim 3, wherein the minimum distance between the welding mark (2) and the peripheral side of the negative current collecting plate (1) is L 2 , wherein L 2 is more than or equal to 0.5mm and less than or equal to 1.5mm.
  7. 7. A negative current collecting plate welding assembly according to claim 6, wherein the minimum distance between the welding mark (2) and the peripheral side of the boss (3) is L 3 , wherein L 3 is more than or equal to 0.5mm and less than or equal to 1.5mm.
  8. 8. A negative current collector plate welding assembly according to any of claims 1-7, wherein four of said welds (2) are arranged in a circumferential array about the axis of said negative current collector plate (1).
  9. 9. A negative current collecting plate welding assembly according to claim 4, wherein the minimum distance between two adjacent welding lines (21) is W 10 , wherein W 10 is 0.6mm or less or 1.1mm or less.
  10. 10. A cylindrical lithium ion battery comprising a negative current collecting plate welding assembly according to any one of claims 1-9.

Description

Negative electrode current collecting disc welding assembly and cylindrical lithium ion battery Technical Field The utility model relates to the technical field of cylindrical batteries, in particular to a welding assembly of a negative electrode current collecting disc and a cylindrical lithium ion battery. Background With the continuous development of new energy technology, batteries are widely applied to various portable electronic products, electric vehicles and large-scale energy storage systems as high-efficiency energy storage equipment, wherein cylindrical lithium ion batteries gradually become one of the main streams of the market due to the excellent performance and high energy density. Welding is used as a reliable connection mode, can provide stronger mechanical strength, and makes two components that weld together switch on, and in the assembly process of cylinder lithium ion battery, utilizes laser welding or ultrasonic welding mode to rub the flat layer with the shell bottom and the core negative pole side with negative pole current collecting disc and fix, can ensure that electric current conducts between core and the shell. The invention patent with publication number CN114597504A discloses a safety component of a cylindrical lithium battery with low internal resistance and no electrode lug, which is provided with a welding part on a negative electrode current collecting disc to ensure that the welding part is welded and fixed with the electrode lug, however, the welding part occupies a larger area on the negative electrode current collecting disc, and the problems of false welding, explosion point and the like easily occur in the welding process of the welding part and the electrode lug, thereby not only being not beneficial to guaranteeing the welding reliability, but also influencing the overall performance of the battery. Disclosure of utility model In view of the above, the utility model provides a welding assembly for a negative electrode current collecting disc and a cylindrical lithium ion battery, which can improve the welding reliability of the negative electrode current collecting disc and a winding core and ensure the overall performance of the battery. The technical scheme of the utility model is realized in such a way that in one aspect, the utility model provides a welding component of a negative current collecting disc, which comprises the negative current collecting disc and a plurality of welding marks positioned on the negative current collecting disc; the welding mark is used for welding and fixing the negative electrode current collecting disc and the rolling core negative electrode side rolling layer, a welding track of the negative electrode current collecting disc and the rolling core negative electrode side rolling layer is the welding mark, and a region, fixedly connected with the rolling core negative electrode side rolling layer through one welding mark, on the negative electrode current collecting disc is a welding surface; The area of the negative electrode current collecting disc is S 0, and the area of each welding surface is S 1, wherein 3% of S 0≤S1≤5％ S0. On the basis of the above technical solution, preferably, the sum of the areas of the plurality of welding surfaces is S 10, wherein 10% S 0≤S10≤20％ S0. On the basis of the technical scheme, the cathode current collecting plate comprises a boss, wherein the boss is fixedly arranged on the cathode current collecting plate and is used for being welded and fixed with the bottom of the shell, and the area of the boss is S 2, wherein 5% of S 0≤S2≤15％ S0 is adopted. On the basis of the technical scheme, preferably, the welding mark comprises a plurality of welding lines, wherein the welding lines are wavy, and the welding lines are arranged at intervals; The welding surface is rectangular, the length of the welding surface is L 1, and the width of the welding surface is W 1, wherein L 1 which is more than or equal to 3.5mm and less than or equal to 5.5mm, and W 1 which is more than or equal to 1.6mm and less than or equal to 3.4mm. Still more preferably, the negative electrode current collecting plate and the boss are both circular; The radius of the cathode current collecting disc is R 0, the radius of the boss is R 1, wherein R 0 is more than or equal to 8.5mm and less than or equal to 10.5mm, and R 1 is more than or equal to 2mm and less than or equal to 4mm. Still more preferably, the minimum distance between the solder mark and the peripheral side of the negative electrode current collecting plate is L 2, wherein L 2 is more than or equal to 0.5mm and less than or equal to 1.5mm. Still more preferably, the minimum distance between the solder marks and the circumferential side of the boss is L 3, wherein L 3 is more than or equal to 0.5mm and less than or equal to 1.5mm. On the basis of the technical scheme, preferably, the welding marks are arranged in four, and the four welding marks are arranged in a cir