Connecting piece of lithium ion battery and battery system

Abstract

The utility model provides a connecting piece of a lithium ion battery and a battery system. The connecting piece comprises a tab ultrasonic welding part, a slope part and a laser welding part which are connected in sequence, the distance between the top surface of the lower plastic part and the top surface of the pole is the height difference value of the cover part; the thicknesses of the tab ultrasonic welding part, the slope part and the laser welding part in the vertical direction are the same; the height difference between the bottom surface of the laser welding part and the bottom surface of the tab ultrasonic welding part is a slope height value; the value obtained by subtracting the height value of the slope from the height difference value of the cover part is equal to a preset difference value, and the value range of the preset difference value is-0.4 mm to 0.4 mm; embossing is arranged on the laser welding part. By means of the structure of the connecting piece of the lithium ion battery, the connecting piece of the lithium ion battery is convenient to process, the lower plastic part is attached to the tab ultrasonic welding part, the pole is attached to the laser welding part, the welding yield is improved, the sinking risk of the pole is reduced, and the connecting piece of the lithium ion battery is not prone to loosening after being welded to the top cover.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium ion batteries, in particular to a connecting piece and a battery system of a lithium ion battery. Background Art

[0002] In lithium-ion batteries, poles are provided on the lower plastic part of the top cover, and the poles protrude from the top surface of the lower plastic part, that is, there is a height difference between the top surface of the poles and the top surface of the lower plastic part. The existing connecting piece is welded to both the lower plastic part and the pole. Since the bottom surface of the connecting piece is a plane, there is a large gap between the connecting piece and the lower plastic part when the connecting piece is welded to the pole. Even if the connecting piece is welded to the lower plastic part, the welding area between the connecting piece and the lower plastic part may still become loose during vibration. In addition, when the existing connecting piece is welded to the pole, the connecting piece and the pole cannot remain flat, which results in an increase in the laser power, which increases the risk of the sealing ring around the pole sinking. How to design a connecting piece that can improve the welding yield is a problem that needs to be solved by those skilled in the art. Utility Model Content

[0003] In view of the above-mentioned shortcomings of the prior art, the technical problem solved by the present invention is to provide a connecting piece and a battery system for a lithium-ion battery that can improve the welding yield.

[0004] To achieve the above-mentioned and other related purposes, the present invention provides a connecting piece for a lithium-ion battery, comprising: a tab ultrasonic welding component, a slope component, and a laser welding component connected in sequence; the tab ultrasonic welding component is used to weld to the lower plastic part of the top cover, and the laser welding component is used to weld to the pole of the top cover, and the distance between the top surface of the lower plastic part and the top surface of the pole is the height difference of the cover;

[0005] In the vertical direction, the thickness of the tab ultrasonic welding component, the thickness of the slope component and the thickness of the laser welding component are the same;

[0006] The laser welding component and the tab ultrasonic welding component are arranged in parallel, and the slope component is inclined relative to the laser welding component. The bottom of the slope component is connected to the tab ultrasonic welding component, and the top of the slope component is connected to the laser welding component. The bottom surface of the laser welding component is higher than the bottom surface of the tab ultrasonic welding component. The height difference between the bottom surface of the laser welding component and the bottom surface of the tab ultrasonic welding component is the slope height value;

[0007] The height difference of the cover minus the slope height is equal to a preset difference, and the preset difference ranges from -0.4 mm to 0.4 mm;

[0008] The laser welding component is provided with embossing.

[0009] Preferably, the slope height is 0.2 mm to 1.0 mm.

[0010] Preferably, a circular through hole is provided on the tab ultrasonic welding component.

[0011] Furthermore, the radius of the circular through hole is 2 mm to 8 mm.

[0012] Preferably, the laser welding component is rectangular.

[0013] Preferably, auxiliary support portions are provided on both sides of the laser welding component; each of the auxiliary support portions is connected to a side of the slope component away from the tab ultrasonic welding component.

[0014] The utility model also relates to a battery system, comprising: the connecting piece of the lithium-ion battery.

[0015] As described above, the lithium-ion battery connector and battery system of the present invention have the following beneficial effects:

[0016] The structure of the connecting piece of the lithium-ion battery, the arrangement of a slope component between the ultrasonic welding component of the tab and the laser welding component, and the preset difference value range make the connecting piece of the lithium-ion battery easy to process, and the lower plastic part fits with the ultrasonic welding component of the tab, and the pole fits with the laser welding component, thereby improving the welding yield and reducing the risk of pole sinking. After the connecting piece of the lithium-ion battery is welded to the top cover, it is not easy to loosen; the laser welding component is provided with embossing, which can avoid poor explosion points caused by high laser reflection. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Shown is a schematic top view of the connecting piece of the lithium-ion battery of this embodiment.

[0018] Figure 2 Shown is a schematic side structural diagram of the connecting piece of the lithium-ion battery of this embodiment.

[0019] Figure 3 It is a schematic diagram of the three-dimensional structure of the lithium-ion battery of this embodiment when no circular through hole is provided on the connecting piece.

[0020] Figure 4 It shows a schematic diagram of the three-dimensional structure of the lithium-ion battery of this embodiment, in which the connecting piece, the tab ultrasonic welding component is welded to the lower plastic part of the top cover, and the laser welding component is welded to the pole of the top cover.

[0021] Figure 5 Shown is a schematic cross-sectional structural diagram of the top cover of this embodiment.

[0022] Explanation of Figure Numbers

[0023] 1 Top cover

[0024] 11 Lower plastic parts

[0025] 12 poles

[0026] 100 Tab Ultrasonic Welding Parts

[0027] 110 round through hole

[0028] 200 Ramp Parts

[0029] 300 Laser Welded Parts

[0030] 310 embossing

[0031] 320 auxiliary support part

[0032] H1 Slope height value

[0033] H2 Cover height difference

[0034] L1 Length of laser welded part

[0035] W1 Width of laser welded part DETAILED DESCRIPTION

[0036] The following describes the implementation of the present invention through specific embodiments. People familiar with this technology can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0037] Please refer to the accompanying drawings. It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of this utility model. Therefore, they have no substantial technical significance. Any modification of the structure, change in the proportional relationship or adjustment of the size should still fall within the scope of the technical content disclosed in this utility model without affecting the efficacy and purpose that can be achieved by this utility model. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description and are not used to limit the scope of the implementation of this utility model. Changes or adjustments in their relative relationships should also be regarded as the scope of the implementation of this utility model without substantially changing the technical content.

[0038] like Figures 1 to 5As shown, the connecting piece of the lithium-ion battery of this embodiment includes: a tab ultrasonic welding component 100, a slope component 200, and a laser welding component 300 connected in sequence; the tab ultrasonic welding component 100 is used to weld to the lower plastic part 11 of the top cover 1, and the laser welding component 300 is used to weld to the pole 12 of the top cover 1. The distance between the top surface of the lower plastic part 11 and the top surface of the pole 12 is the cover height difference H2;

[0039] In the vertical direction, the thickness of the tab ultrasonic welding component 100, the thickness of the slope component 200 and the thickness of the laser welding component 300 are the same;

[0040] The laser welding component 300 is arranged parallel to the tab ultrasonic welding component 100, and the slope component 200 is arranged obliquely relative to the laser welding component 300. The bottom of the slope component 200 is connected to the tab ultrasonic welding component 100, and the top of the slope component 200 is connected to the laser welding component 300. The bottom surface of the laser welding component 300 is higher than the bottom surface of the tab ultrasonic welding component 100. The height difference between the bottom surface of the laser welding component 300 and the bottom surface of the tab ultrasonic welding component 100 is the slope height value H1;

[0041] The cover height difference H2 minus the slope height H1 equals a preset difference, and the preset difference ranges from -0.4 mm to 0.4 mm. In this embodiment, the preset difference is 0.3 mm.

[0042] The laser welding component 300 is provided with embossing 310 .

[0043] The structure of the connecting piece of the lithium-ion battery, the slope component 200 is set between the tab ultrasonic welding component 100 and the laser welding component 300, and the range of the preset difference value makes the connecting piece of the lithium-ion battery easy to process, and the lower plastic part 11 is fitted with the tab ultrasonic welding component 100, and the pole 12 is fitted with the laser welding component 300, which improves the welding yield and reduces the risk of the pole 12 sinking. After the connecting piece of the lithium-ion battery is welded to the top cover 1, it is not easy to loosen. The flatter the bottom surface of the laser welding component 300, the more stable the laser power used, and the laser power will not increase, effectively avoiding the risk of the sealing ring around the pole 12 sinking. The laser welding component 300 is provided with embossing 310, which can avoid the poor explosion point caused by high laser reflection.

[0044] The slope height H1 is 0.2 mm to 1.0 mm. The slope height H1 enables the lithium-ion battery connecting piece to be suitable for use in the existing top cover 1. In this embodiment, the slope height H1 is 0.6 mm.

[0045] The tab ultrasonic welding component 100 is provided with a circular through-hole 110. This circular through-hole 110 prevents interference with the liquid injection hole, allowing liquid to pass through it, thereby improving injection efficiency. The radius of the circular through-hole is between 2 mm and 8 mm. In this embodiment, the radius of the circular through-hole is 5 mm.

[0046] For ease of processing, the laser welding component 300 is rectangular. In this embodiment, the laser welding component 300 is a square area, the length L1 of the laser welding component 300 is 27 mm, and the width W1 of the laser welding component 300 is 27 mm.

[0047] Auxiliary support parts 320 are provided on both sides of the laser welding component 300; each auxiliary support part 320 is connected to the side of the ramp component 200 away from the tab ultrasonic welding component 100. This allows both sides of the laser welding component 300 to be more stably connected to the ramp component 200.

[0048] A battery system of this embodiment includes a connecting piece of a lithium-ion battery.

[0049] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical principles disclosed in the present invention are intended to be covered by the claims of the present invention.

Claims

1. A connecting piece for a lithium-ion battery, characterized in that: include: A tab ultrasonic welding component (100), a slope component (200), and a laser welding component (300) are sequentially connected; the tab ultrasonic welding component (100) is used to weld with the lower plastic part (11) of the top cover (1), and the laser welding component (300) is used to weld with the pole (12) of the top cover (1); the distance between the top surface of the lower plastic part (11) and the top surface of the pole (12) is the height difference of the cover; In the vertical direction, the thickness of the tab ultrasonic welding component (100), the thickness of the slope component (200), and the thickness of the laser welding component (300) are the same; The laser welding component (300) and the tab ultrasonic welding component (100) are arranged in parallel, the slope component (200) is arranged obliquely relative to the laser welding component (300), the bottom of the slope component (200) is connected to the tab ultrasonic welding component (100), the top of the slope component (200) is connected to the laser welding component (300), the bottom surface of the laser welding component (300) is higher than the bottom surface of the tab ultrasonic welding component (100), and the height difference between the bottom surface of the laser welding component (300) and the bottom surface of the tab ultrasonic welding component (100) is the slope height value; The height difference of the cover minus the slope height is equal to a preset difference, and the preset difference ranges from -0.4 mm to 0.4 mm; The laser welding component (300) is provided with embossing (310).

2. The connecting piece of a lithium-ion battery according to claim 1, characterized in that: The slope height is 0.2 mm to 1.0 mm.

3. The connecting piece of a lithium-ion battery according to claim 1, characterized in that: A circular through hole (110) is provided on the tab ultrasonic welding component (100).

4. The connecting piece of the lithium-ion battery according to claim 3, characterized in that: The radius of the circular through hole (110) is 2 mm to 8 mm.

5. The connecting piece of the lithium-ion battery according to claim 1, characterized in that: The laser welding component (300) is rectangular.

6. The connecting piece of the lithium-ion battery according to claim 1, characterized in that: Auxiliary support parts (320) are provided on both sides of the laser welding component (300); each of the auxiliary support parts (320) is connected to a side of the slope component (200) away from the tab ultrasonic welding component (100).

7. A battery system comprising: The connecting piece of a lithium-ion battery according to any one of claims 1 to 6.

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