Laser welding device for multi-layer current collector and outer tab

Abstract

The invention discloses a laser welding device for a multi-layer current collector and an outer tab, which comprises a battery cell placing platform used for positioning a battery cell and enabling at least one part of the current collector of the battery cell to be suspended; the welding table driving mechanism is used for driving the welding table to be close to the battery cell placing platform from the lower part, so that the upper surface of the welding table or the outer tab placed on the upper surface of the welding table is attached to the lower surface of the suspended current collector; the welding pressure head driving mechanism is used for driving the welding pressure head to be close to the battery cell placing platform from the upper part so as to press the suspended current collector and the outer tab on the welding table; and the laser welding head is used for carrying out laser welding on the pressed current collector and the outer tab. Compared with an ultrasonic welding system, the welding quality can be improved from the process aspect, the welding process can be simplified, the two steps of pre-welding and final welding are optimized into one-step laser welding, the aging is improved, and the equipment development cost is reduced.

Description

technical field [0001] The invention relates to a battery welding technology, in particular to a laser welding device for a multilayer current collector and an outer tab. Background technique [0002] The basic structure of a lithium battery is the result of stacking multiple layers of positive and negative plates and separators in a regular manner. The movement of active particles on the plates dominates the charging and discharging process. Whether charging or discharging, the interaction between the lithium battery and the external current is necessary. The tab connection is the key to this communication. The tabs extending from the pole pieces are copper current collectors or aluminum current collectors. The connection between the multi-layer current collectors and the outer tabs (aluminum, nickel or copper nickel-plated) directly affects the current flow of the cell. Therefore, the welding quality of the multilayer current collector and the outer tab is very important....

AI Technical Summary

Problems solved by technology

However, the high-frequency friction vibration of the contact type is easy to cause damage or even breakage of the current collector, resulting in failure of the tab connection

In addition, in a new generation of high-energy-density batteries, graphene-coated aluminum foil current collectors have been used in positive electrode sheets. The lubricating graphene will affect the friction conduction between current collectors, thereby affecting the quality of ultrasonic welding and even welding. fail

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