The batteries that provide driving power for electric vehicles are called power batteries, including traditional lead-acid batteries, nickel metal hydride batteries and emerging lithium ion power batteries, which are divided into power type power batteries (hybrid vehicles) and energy type power batteries (pure electric vehicles). As we all know, power battery is the "heart" of new energy vehicles. The power lithium battery mainly consists of ternary material battery and lithium iron phosphate battery. The downstream is the installed application of new energy vehicles, which has higher discharge power than ordinary batteries. In the production process of power battery, welding is a very important manufacturing process from cell manufacturing to PACK assembly. In particular, the power battery structure contains a variety of materials, such as steel, aluminum, copper, nickel and other metals that may be made into electrodes, wires or shells. Therefore, whether it is the welding between one material or multiple materials, higher requirements are put forward for the welding process.

Laser welding is to use the excellent directivity and high power density of the laser beam to work. The laser beam is focused in a very small area through the optical system to form a heat source area with highly concentrated energy in a very short period of time, so that the welded object can melt and form a solid welding spot and weld.

In the whole industrial chain of power battery, laser welding is mainly used in the midstream production of power lithium battery. As a high-precision welding method, it is extremely flexible, accurate and efficient, and can meet the performance requirements in the production process of power battery. It is the first choice in the manufacturing process of power battery, and has become the standard equipment of power battery production line.