Welding method of tabs and cover plate and battery assembly

Abstract

The invention discloses a welding method for tabs and a cover plate and an electrode assembly. The welding method comprises the following steps: carrying out ultrasonic welding on multiple layers of tabs to form a welding printing area, wherein the density of the welding printing area is not lower than preset density; carrying out laser pre-welding on the welding area of the tabs and the cover plate, melting part of metal at a welding seam, and reserving a welding mark at the welding area; and performing laser final welding on the welding area of the tabs and the cover plate, and connecting the tabs with the cover plate. Therefore, according to the welding method, the tabs can be directly connected with the cover plate without adding a protection sheet and a transition sheet, so that the weight of a battery can be reduced, the volume specific capacity and the weight specific capacity of the battery are improved, the pseudo soldering risk is reduced; and meanwhile, the whole technological process can be optimized, a protection sheet manufacturing process and a transition sheet process are omitted, the production process can be simplified, and the battery production cost can be reduced.

Description

technical field [0001] The invention relates to the technical field of batteries, in particular to a welding method for a tab and a cover plate and a battery assembly. Background technique [0002] With the development of science and technology and human consumption of traditional energy, new energy vehicles have gradually entered people's lives due to their high environmental protection. As the top priority of the development of new energy vehicle technology, power battery technology, battery connection technology, especially welding technology is a key part of battery manufacturing technology. [0003] In the related process, if you want to weld the battery tab and the cover plate, most of them use soft connections for transition. In this welding method, the battery tab needs two layers of protection sheets, which will increase the weight of the battery and occupy the space of the battery. In order to protect the battery tabs, the protective sheet needs blunt edge treatme...

AI Technical Summary

Problems solved by technology

This will lead to high internal resistance of the battery and high heat generation temperature during charging and discharging, and metal debris will also have a serious impact on battery safety.

[0005] Furthermore, the existence of the flexible connecting piece also invades the internal space of the battery, resulting in a low volume specific energy of the battery; moreover, the flexible connecting piece needs to be bent, which reduces the production efficiency and increases the equipment investment cost

Images