A novel cylindrical battery current collector plate

Abstract

The utility model relates to a novel cylindrical battery current collecting disc belongs to cylindrical battery technical field, including the explosion -proof valve of current collecting disc middle part and the welding groove of current collecting disc periphery a plurality of, the adjacent welding groove between being equipped with the shell fragment, the shell fragment is equipped in current collecting disc back, the shell fragment first end is fixed in current collecting disc back, the middle end is away from current collecting disc plane and extends outward, tail end parallel to current collecting disc back, this current collecting disc simple structure, easy operation, can effectively alleviate cylindrical full tab battery current collecting disc welding abnormality and then influence the difficult problem of difficult flow guide, can effectively improve the flow guide, internal resistance and the problem such as burst point, reduce the laser welding frequency and improve the welding yield, improve the efficiency of battery cell liquid injection, increase the battery cell overcurrent capacity, current collecting disc itself as the sealing piece of cylindrical shell port, reduce the application of structural member.

Description

TECHNICAL FIELD

[0001] The utility model relates to a novel cylindrical battery current collecting disc belongs to cylindrical battery technical field. BACKGROUND

[0002] The full tab design of the cylindrical battery cell fundamentally improves the charge-discharge efficiency, power output, safety, cycle life and energy density of the cylindrical battery cell by optimizing the current path, heat distribution and structural space, making it more suitable for high-demand application scenarios such as new energy vehicles or energy storage devices, and is one of the important directions for current cylindrical battery cell technology upgrading. The positive and negative full tabs of the cylindrical battery cell are connected to the current collecting disc by welding and connected to the external circuit for power supply.

[0003] The full tab cylindrical battery assembly process is complex. First, the positive plate, negative plate and separator are wound into a core, then the positive and negative tabs of the core are rubbed and flattened, and after rubbing and flattening, the positive and negative current collecting discs, cover plates and poles are sequentially assembled and welded with the core. The full tab structure cylindrical battery still needs to weld the current collecting disc with the shell after welding the current collecting disc, and then weld the sealing sheet structure for sealing. During the welding process of the rubbed full tab and the current collecting disc, the core height tolerance and the current collecting disc tolerance may have a virtual welding problem, and multiple welding may also cause more welding defects.

[0004] The full tab structure cylindrical battery still needs to weld the sealing sheet structure for end face sealing of the battery cell after welding the current collecting disc, and multiple laser welding increases the risk of welding defects such as explosion points; the sealing sheet is welded after the tab is welded with the current collecting disc, and the structure occupies the weight and volume of the battery cell; the welding area of the rubbed tab is limited, which affects the overcurrent area and the rate charge-discharge performance, so it is crucial to develop a new type of cylindrical battery current collecting disc. UTILITY MODEL CONTENTS

[0005] In view of the deficiencies in the prior art, the utility model provides a novel cylindrical battery current collecting disc.

[0006] The technical scheme for solving the above technical problems is as follows: A novel cylindrical battery current collecting disc, comprising an explosion-proof valve arranged in the middle part of the current collecting disc and a plurality of welding grooves arranged in the circumferential direction of the current collecting disc, wherein a spring sheet is arranged between adjacent welding grooves, and the spring sheet is arranged on the back surface of the current collecting disc.

[0007] Further, the first end of the spring sheet is fixed to the back surface of the current collecting disc, the middle end extends outward away from the plane of the current collecting disc, and the tail end is parallel to the back surface of the current collecting disc.

[0008] Further, the included angle between the middle end of the spring sheet and the back surface of the current collecting disc is in the range of 30°-60°.

[0009] Further, the height from the tail end of the spring sheet to the back surface of the current collecting disc is greater than the depth of the welding groove.

[0010] Further, the width of the elastic sheet ranges from 1.5 MM to 2.5 MM.

[0011] Further, the adjacent welding grooves are provided with liquid injection holes.

[0012] Further, the welding step is arranged at the circumferential edge of the current collecting disc.

[0013] Further, the number of the welding grooves ranges from 4 to 6.

[0014] Further, the upper opening area of the welding groove is larger than the area of the bottom plane.

[0015] Further, the welding grooves are uniformly arranged on the circumference of the current collecting disc.

[0016] Compared with the prior art, the current collecting disc has the advantages that: the structure is simple and easy to operate, the problem of difficult flow guiding caused by abnormal welding of the current collecting disc of the cylindrical full-tab battery is effectively solved, the problems of flow guiding, internal resistance and explosion point are effectively improved, the number of laser welding is reduced and the welding yield is improved, the efficiency of liquid injection of the battery cell is improved, the overcurrent capacity of the battery cell is increased, the current collecting disc itself serves as a sealing sheet of the cylindrical shell port, and the application of structural parts is reduced. By designing the welding groove as a recessed structure, the welding groove can be in close contact with the flattened full tab, the welding groove and the tab are in interference connection, the problems of penetration welding explosion point and virtual welding are reduced, the welding wire is in the welding groove, the sealing property of the welding wire can be further improved by filling the welding groove with glue, that is, the welding wire in the welding groove is protected by strong casting glue to prevent liquid leakage of the welding pinhole in the subsequent application process of the battery cell. The existence of the elastic sheet can increase the contact area between the flattened tab and the current collecting disc, thereby increasing the flow area of the current collecting disc and the flattened full tab and improving the flow efficiency. By designing the liquid injection hole at the position above the elastic sheet, the elastic sheet can slow down the impact of the liquid flow on the tab during high-pressure liquid injection, and the space supported by the elastic sheet and the welding groove further improves the liquid injection efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0017] Fig. 1 It is a front structure schematic view of the current collecting disc of the utility model.

[0018] Fig. 2 It is a back structure schematic view of the current collecting disc of the utility model.

[0019] In the drawings, 1 is a welding groove, 2 is an explosion-proof valve, 3 is a liquid injection hole, and 4 is an elastic sheet. DETAILED DESCRIPTION

[0020] The principles and characteristics of the utility model are described below in combination with the drawings, and the examples are only used to explain the utility model and not to limit the scope of the utility model.

[0021] As shown in the figure, a novel cylindrical battery current collecting disc comprises an explosion-proof valve 2 arranged in the middle of the current collecting disc and a plurality of welding grooves 1 arranged in the circumferential direction of the current collecting disc, and a spring sheet 4 is arranged between adjacent welding grooves 1. Figs. 1-2

[0022] The first end of the spring sheet 4 is fixed to the back surface of the current collecting disc, the middle end extends outward away from the plane of the current collecting disc, and the tail end is parallel to the back surface of the current collecting disc.

[0023] The angle between the middle end of the spring sheet 4 and the back surface of the current collecting disc ranges from 30° to 60°.

[0024] The height of the tail end of the spring sheet 4 to the back surface of the current collecting disc is greater than the depth of the welding groove 1.

[0025] The adjacent welding grooves 1 are provided with a liquid injection hole 3.

[0026] The circumferential edge of the current collecting disc is provided with a welding step.

[0027] The number of the welding grooves 1 is 4-6.

[0028] The upper opening area of the welding groove 1 is greater than the area of the bottom plane.

[0029] The welding grooves 1 are uniformly arranged in the circumferential direction of the current collecting disc.

[0030] The novel cylindrical battery current collecting disc is formed by stamping, and the spring sheet 4 and the explosion-proof valve 2 are contacted by laser welding, the welding groove 1 can provide sufficient interference after the current collecting disc is pressed with the winding core, the penetration welding is carried out in the welding groove 1 of the current collecting disc and the tab, the welding defects such as welding burst point and pinhole caused by loose contact are reduced, the strong casting glue is filled in the welding groove 1 after welding, the welding strength is improved, even if there are welding burst point and pinhole defects, the repair welding can be omitted, and the production efficiency is improved; the height of the spring sheet 4 to the back surface of the current collecting disc is greater than the welding groove 1, when the current collecting disc is pressed with the winding core, the contact area between the tab and the current collecting disc can be increased, and the current efficiency is improved; the liquid injection hole 3 is located above the spring sheet 4, the spring sheet 4 slows down the impact of the liquid flow on the tab during high-pressure liquid injection, and the space supported by the spring sheet 4 and the welding groove 1 improves the liquid injection efficiency; after the current collecting disc and the cylindrical shell are welded around the periphery, the penetration welding is carried out with the tab, and the welding groove is coated with glue and filled, the battery cell has been basically sealed, after liquid injection, only a small sealing piece is used to seal the liquid injection port, the required welding area is small, the defects are reduced, and the process operation is simple.

[0031] ​The current collecting disc structure is simple and easy to operate, can effectively alleviate the problem of welding abnormality of the current collecting disc of the cylindrical full-tab battery, and further affect the difficult flow guide, can effectively improve the flow guide, internal resistance and burst point and other problems, reduce the number of laser welding and improve the welding yield, improve the efficiency of the battery liquid injection, increase the overcurrent capacity of the battery, and the current collecting disc itself as a sealing piece of the cylindrical shell port reduces the application of structural parts; By designing the welding groove 1 as a recessed structure, the welding groove 1 can be in close contact with the flattened full tab, so that the welding groove 1 is in interference connection with the tab, reducing the problems of through-welding burst point and virtual welding. The welding wire can be filled in the welding groove 1 by gluing to further improve the sealing of the welding wire, that is, the welding wire in the welding groove 1 is protected by strong casting glue to prevent welding pinholes from leaking during subsequent battery application. The presence of the elastic sheet 4 can increase the contact area between the flattened tab and the current collecting disc, thereby increasing the overcurrent area of the current collecting disc and the flattened full tab and improving the overcurrent efficiency. By designing the liquid injection hole 3 above the elastic sheet 4, the elastic sheet 4 can slow down the impact of the liquid flow on the tab during high-pressure liquid injection, and the space supported by the elastic sheet 4 and the welding groove 1 further improves the liquid injection efficiency.

[0032] The above only describes the preferred embodiments of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A novel cylindrical battery current collector, characterized in that: It includes an explosion-proof valve (2) located in the middle of the collector plate and several welding grooves (1) located around the collector plate. A spring (4) is provided between adjacent welding grooves (1) and the spring (4) is located on the back of the collector plate.

2. The novel cylindrical battery current collector according to claim 1, characterized in that: The first end of the spring piece (4) is fixed to the back of the collector plate, the middle end extends outward away from the plane of the collector plate, and the tail end is parallel to the back of the collector plate.

3. The novel cylindrical battery current collector according to claim 2, characterized in that: The included angle between the middle end of the spring piece (4) and the back of the collector plate is 30°-60°.

4. The novel cylindrical battery current collector according to claim 2, characterized in that: The height of the end of the spring (4) to the back of the collector plate is greater than the depth of the welding groove (1).

5. The novel cylindrical battery current collector according to claim 1 or 2, characterized in that: The width of the spring piece (4) ranges from 1.5 mm to 2.5 mm.

6. The novel cylindrical battery current collector according to claim 1, characterized in that: A liquid injection hole (3) is provided between the adjacent welding grooves (1).

7. The novel cylindrical battery current collector according to claim 1 or 2, characterized in that: The collector plate has a welding step at its circumferential edge.

8. The novel cylindrical battery current collector according to claim 1 or 6, characterized in that: The number of welding grooves (1) is 4-6.

9. The novel cylindrical battery current collector according to claim 1 or 6, characterized in that: The upper opening area of ​​the welding groove (1) is larger than the area of ​​the bottom plane.

10. The novel cylindrical battery current collector according to claim 1, characterized in that: The welding groove (1) is evenly distributed around the circumference of the collecting plate.

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