Battery cell connecting assembly, lithium battery and assembling method

Abstract

The invention provides a battery cell connecting assembly which comprises an end cover capable of being buckled at one end of at least one battery cell, the end, covered by the end cover, of the battery cell is provided with a positive tab and a negative tab, two pole pieces are arranged on the outer side of the end cover and connected with a bottom piece located on the inner side of the end cover, and the bottom piece can be welded and fixed with the positive tab or the negative tab. The invention further provides a lithium battery comprising the connecting assembly and an assembling method. The battery cell connecting assembly has the advantages that the bottom piece and the pole piece are connected together, so that the bottom piece and the pole piece are conveniently fixed with a pole lug of a battery cell, the pole piece and the bottom piece are directly fixed on the connecting assembly, the whole connecting assembly is directly operated during assembly, the pole piece and the connecting piece which are separately arranged do not need to be frequently sucked, equipment shutdown caused by multiple pieces and missing pieces is reduced, and the utilization rate is improved. And the tabs are fixed when the pole pieces are turned over, so that the condition that the tabs are inserted inwards is avoided.

Description

technical field [0001] The invention relates to the technical field of lithium batteries, in particular to a battery cell connection assembly, a lithium battery and an assembly method. Background technique [0002] The current traditional lithium battery cell assembly method is as follows: ① Use the "butterfly welding" process to connect two single cells together, that is, use ultrasonic welding to weld the two poles of the same polarity through the connecting sheet and the protective sheet; ② The above-mentioned connecting piece is welded together with the pole corresponding to the same polarity by laser. In order to protect the pole, the stop frame is generally buckled at the welding mark to prevent loosening. For example, a patent application with a publication number of CN105261798A is suitable for The assembly device and assembly method for assembling the square lithium battery pole group; ③ Combine the above two single cells and fix them with binding tape; ④ Insert the...

AI Technical Summary

Problems solved by technology

[0004] 1. The connection piece and the protection piece are all separate thin pieces. During the feeding process, there will be frequent phenomena such as multiple pieces and missing pieces, resulting in a low manufacturing utilization rate.

[0005] 2. During the ultrasonic welding process of the connecting sheet and the protective sheet with the tab, it is very easy to shake, and it is difficult to ensure the positioning accuracy of the two on the tab, resulting in poor quality of ultrasonic welding

[0006] 3. The manufacturing process of buckling the stopper is relatively complicated, involving many processes such as stopper buffering, feeding, buckling, buckle height detection, etc., and the quality of the buckle is difficult to effectively guarantee

[0007] 4. When the battery cells are combined, the tabs are prone to be inserted into the battery core body to cause a short circuit of the battery, and when the connecting piece is bent, it is easy to cause damage to the battery tabs, which reduces the manufacturing pass rate

[0008] 5. The scope of application of this method is narrow, and it can only be used for lithium battery assembly when the number of cells is even

And when the number of batteries > 4, the tab interpolation phenomenon of this method is more serious and difficult to effectively solve

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