Collector plate of cylindrical lithium ion battery
By introducing a large-area boss support structure and liquid guiding groove design into the current collector of the cylindrical lithium-ion battery, the problem of welding instability caused by the lack of support in the steel shell structure is solved, the welding stability and current uniformity of the battery are improved, the internal resistance is reduced, and the electrolyte injection efficiency and rate performance of the battery are improved.
Patent Information
- Application Number
- CN202422425269.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-09
- Publication Date
- 2025-12-19
- Estimated Expiration
- 2034-10-09
AI Technical Summary
The steel casing structure of existing cylindrical lithium-ion batteries suffers from a lack of support during the production process, leading to unstable welding between the current collector and the casing. Furthermore, traditional current collectors have low strength and are prone to warping, affecting the welding quality of the battery.
A cylindrical lithium-ion battery current collector was designed, which adopts a large-area boss support structure in the middle of the shell welding area, combined with the hollow design of the liquid guiding groove and the uniform distribution of the electrode welding area, to enhance the welding stability between the current collector and the shell, and improve the welding strength through laser welding technology.
It improves the welding stability between the current collector and the casing, enhances the uniformity of current flow and electrolyte injection efficiency, reduces the internal resistance of the battery, and improves the rate performance and current flow capacity of the battery.
Smart Images
Figure CN223693318U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to battery technology field, concretely is a cylindrical lithium ion battery current collecting disc. BACKGROUND
[0002] Cylindrical batteries are widely used in the fields of intelligent furniture, power tools and two-wheeled electric vehicles due to their high mechanical strength, good safety and non-swelling deformation during use. Power tools and two-wheeled electric vehicles require batteries to have high capacity and high power capability to meet the needs of endurance mileage, charging speed and high-power discharge. With the increasing market demand, the diameter and height of cylindrical batteries are continuously increasing, from the initial 18650 model to the 21700 / 26700 / 32140 / 40135 / 4680 / 46120 / 60150 model, and the volume and weight of the battery are continuously increasing.
[0003] A large cylindrical full-tab cylindrical battery is an extremely effective way to improve the rate performance of cylindrical batteries. The manufacturing method is to set positive and negative full tabs at both ends of the winding core. Flexible tabs need to be attached to both ends of the winding core by extrusion, flattening or flattening. Since the tabs at both ends of the winding core are flexible tabs, the end face cannot be guaranteed to be flat, which leads to poor welding stability of the current collecting disc and the tabs. In order to avoid damage to the heat-shrinkable sleeve during production, the bottom of the steel shell is provided with a boss, and the traditional current collecting sheet has low strength and no support between the boss of the steel shell, which is prone to warping after being extruded by the winding core, affecting the welding of the current collecting disc and the shell. SUMMARY
[0004] The utility model aims at providing a cylindrical lithium ion battery current collecting disc to solve the problem of the existing steel shell structure in the prior art mentioned in the background art, which is provided with a boss at the bottom of the steel shell to avoid damage to the heat-shrinkable sleeve during production, the traditional current collecting sheet has low strength and no support between the boss of the steel shell, which is prone to warping after being extruded by the winding core, affecting the welding of the current collecting disc and the shell.
[0005] To achieve the above-mentioned purpose, the utility model provides the following technical scheme: a cylindrical lithium ion battery current collecting disc, comprising a tab welding area, an outer ring of the tab welding area is fixedly provided with a shell welding area, the tab welding area is located between the boss areas, the boss areas are provided with liquid guide grooves, the bottom of the boss area is provided with a boss support, and the bottom of the boss area is provided with a current collecting disc welding point.
[0006] Preferably, the outer edge of the current collecting disc is circular, and the outer diameter of the current collecting disc is less than or equal to the inner diameter of the shell, the shell welding area is a circular plane, a boss is provided in the middle of the circular ring, the boss protrudes towards the side of the shell, and the boss depth is 0.05-1mm.
[0007] Preferably, the shell welding area and the shell are laser welded, and the tab welding area and the tab are laser welded.
[0008] Preferably, the number of the tab welding area is greater than or equal to 2, and is uniformly distributed along the radial direction, and the welding track can be point-shaped, spiral, sinusoidal, straight, or arc-shaped.
[0009] Preferably, the liquid guide groove is hollow, the number is greater than or equal to 2, and is uniformly distributed along the radial direction, and the shape of the liquid guide groove can be circular, square, rhombic, triangular, pentagonal, sector-shaped, or trapezoidal.
[0010] Preferably, all adjacent areas intersect at a rounded corner, the thickness of the current collector plate is greater than or equal to 0.1 mm and less than or equal to 0.5 mm.
[0011] Compared with the prior art, the cylinder lithium ion battery current collector plate has the following beneficial effects:
[0012] 1. The cylinder lithium ion battery current collector plate has the following beneficial effects: the large-area boss in the middle of the shell welding area is beneficial to support the winding core, prevent the edge of the welding area from warping, reduce the gap between the shell and the current collector plate, and improve the welding stability; the strip-shaped welding groove design ensures that the same welding area is reduced, the recess area is reduced, the contact surface pressure of the tab is increased, the tab is better attached, and the welding stability is improved; the tab welding area of the current collector plate is uniformly distributed along the radial direction, which is beneficial to the uniform flow of the current in the battery winding core, shortens the current flow distance, the side wall of the boss and the recess of the current collector plate serves as a reinforcing rib, which can improve the strength of the current collector plate, the boss and the recess are staggered, which makes the current collector plate have reinforcing ribs in all directions, improves the bending resistance of the current collector plate, and the current collector plate is not easy to deform, thereby improving the welding stability.
[0013] 2. The cylinder lithium ion battery current collector plate has the following beneficial effects: the hollow design of the liquid guide groove of the current collector plate is beneficial to improve the efficiency of electrolyte injection and increase the electrolyte infiltration speed; the shell welding area is arranged at the edge of the shell, the welding circle has a maximum diameter, the welding area is larger than the center welding area, the overcurrent energy of the battery is improved, the internal resistance of the battery is reduced, and the rate performance is improved. BRIEF DESCRIPTION OF DRAWINGS
[0014] Figure 1 It is a three-dimensional structure schematic diagram of the current collector plate of the utility model;
[0015] Figure 2 It is a welding line structure schematic diagram of the current collector plate of the utility model
[0016] Figure 3 It is a three-dimensional structure schematic diagram of the boss area with an included angle of 60 degrees of the utility model;
[0017] Figure 4 It is a three-dimensional structure schematic diagram of the boss area with an included angle of 90 degrees of the utility model;
[0018] Figure 5 Figure is the local structure schematic diagram of the welding line of the current collecting disc of the utility model;
[0019] Figure 6 Figure is the local structure schematic diagram of the welding line of the current collecting disc of the utility model.
[0020] In the drawing: 1, the tab welding area; 2, the shell welding area; 3, the boss area; 4, the liquid guide groove hole; 5, the boss support; 6, the current collecting disc welding point. DETAILED DESCRIPTION
[0021] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the utility model.
[0022] Please refer to Figures 1-6 The utility model provides a kind of technical solutions: a cylindrical lithium ion battery current collecting disc, including tab welding area 1, the outer ring of tab welding area 1 is fixedly provided with shell welding area 2, tab welding area 1 is located between boss area 3, boss area 3 is provided with liquid guide groove hole 4, the bottom of boss area 3 is provided with boss support 5, the bottom of boss area 3 is provided with current collecting disc welding point 6.
[0023] The outer edge of the current collecting disc is circular, and the outer diameter of the current collecting disc is less than or equal to the inner diameter of the shell. The shell welding area 2 is a circular ring plane, and a boss is arranged in the middle of the circular ring. The boss is arranged in the direction close to the shell side, and the boss depth is 0.05-1mm. The welding between the shell welding area 2 and the shell is laser welding, and the welding between the tab welding area 1 and the tab is laser welding. The number of tab welding areas 1 is greater than or equal to 2, and is uniformly distributed along the circular diameter direction. The welding track can be point-shaped, spiral line, sine line, straight line, arc line. The liquid guide groove hole 4 is designed as a hollow, and the number is greater than or equal to 2 and is uniformly distributed along the circular diameter direction. The shape of the liquid guide groove hole 4 can be circular, square, diamond, triangular, pentagonal, sector, trapezoidal. All adjacent areas intersecting positions are provided with a fillet transition. The thickness of the current collecting disc is greater than or equal to 0.1mm and less than or equal to 0.5mm. When the cylindrical lithium ion battery current collecting disc is used, the large-area boss design in the middle of the shell welding area 2 is beneficial to support the winding core, prevent the edge of the welding area from warping, reduce the gap between the shell and the current collecting disc, and improve the welding stability. The strip-shaped welding groove design ensures that the same welding area reduces the concave area, increases the contact surface pressure of the tab, and better fits, thereby improving the welding stability. The tab welding area 1 of the current collecting disc is uniformly distributed along the circular diameter direction, which is beneficial to the uniform flow of the current in the battery winding core, shortens the current flow distance, and the side wall of the boss and the concave of the current collecting disc plays a role of reinforcing rib, which can improve the strength of the current collecting disc. The boss and the concave are staggered, so that the current collecting disc has reinforcing ribs in all directions, improves the bending resistance of the current collecting disc, and the current collecting disc is not easy to deform, thereby improving the welding stability. The current collecting disc liquid guide groove hole 4 is designed as a hollow, which is beneficial to improve the electrolyte injection efficiency and increase the electrolyte infiltration speed. The shell welding area 2 is arranged at the edge of the shell, the welding circle diameter is maximized, the welding area is larger than the center welding, the battery overcurrent energy is improved, the battery internal resistance is reduced, and the rate performance is improved.
[0024] Working principle: When the cylindrical lithium ion battery current collecting disc is used, the large-area boss design in the middle of the shell welding area 2 is beneficial to support the winding core, prevent the edge of the welding area from warping, reduce the gap between the shell and the current collecting disc, and improve the welding stability. The strip-shaped welding groove design ensures that the same welding area reduces the concave area, increases the contact surface pressure of the tab, and better fits, thereby improving the welding stability. The tab welding area 1 of the current collecting disc is uniformly distributed along the circular diameter direction, which is beneficial to the uniform flow of the current in the battery winding core, shortens the current flow distance, and the side wall of the boss and the concave of the current collecting disc plays a role of reinforcing rib, which can improve the strength of the current collecting disc. The boss and the concave are staggered, so that the current collecting disc has reinforcing ribs in all directions, improves the bending resistance of the current collecting disc, and the current collecting disc is not easy to deform, thereby improving the welding stability. The current collecting disc liquid guide groove hole 4 is designed as a hollow, which is beneficial to improve the electrolyte injection efficiency and increase the electrolyte infiltration speed. The shell welding area 2 is arranged at the edge of the shell, the welding circle diameter is maximized, the welding area is larger than the center welding, the battery overcurrent energy is improved, the battery internal resistance is reduced, and the rate performance is improved.
[0025] Finally, it should be noted that the above is merely to illustrate the technical solutions of the present application, and is not a limitation on the scope of protection of the present application, and simple modifications or substitutions of the technical solutions of the present application by those skilled in the art do not deviate from the essence and scope of the technical solutions of the present application.
Claims
1. A cylindrical lithium-ion battery current collector tab comprising a tab welding area (1), characterized in that: The outer ring of the tab welding area (1) is fixedly provided with a shell welding area (2), the tab welding area (1) is located between the boss areas (3), the boss area (3) is provided with a liquid guide groove hole (4), the bottom of the boss area (3) is provided with a boss support (5), and the bottom of the boss area (3) is provided with a collector plate welding point (6).
2. The cylindrical lithium-ion battery current collector of claim 1, wherein: The outer edge of the collector plate is circular, the outer diameter of the collector plate is less than or equal to the inner diameter of the shell, the shell welding area (2) is a circular plane, a boss is arranged in the middle of the circular ring, the boss is directed towards the side of the shell, and the boss depth is 0.05-1mm.
3. The cylindrical lithium-ion battery current collector of claim 2, wherein: The welding between the shell welding area (2) and the shell is laser welding, and the welding between the tab welding area (1) and the tab is laser welding.
4. The cylindrical lithium-ion battery current collector of claim 3, wherein: The number of the tab welding area (1) is greater than or equal to 2, and the tab welding areas are uniformly distributed along the radial direction, and the welding traces can be point-shaped, spiral lines, sinusoidal lines, straight lines or arc lines.
5. The cylindrical lithium-ion battery current collector of claim 1, wherein: The liquid guide groove hole (4) is designed to be hollow, the number of the liquid guide groove holes is greater than or equal to 2, and the liquid guide groove holes are uniformly distributed along the radial direction, and the shapes of the liquid guide groove holes can be circular, square, rhombic, triangular, pentagonal, sector-shaped or trapezoidal.
6. The cylindrical lithium-ion battery current collector of claim 5, wherein: All adjacent areas are provided with a round corner transition at the intersection position, the thickness of the collector plate is greater than or equal to 0.1mm and less than or equal to 0.5mm.