In recent years, the battery technology for electric vehicles has developed rapidly, and the driving range has become an important index to measure the performance of electric vehicles. The high-capacity lithium-ion battery system has become the key to improve this index. Through multiple cells in parallel and series, a lithium-ion battery system meeting the requirements of vehicle working voltage and driving range is formed.

The connection between the electric core and the electric core generally adopts the way of connection row welding. In the process of module manufacturing, the soft core module generally adopts laser welding. The application of laser welding machine in the welding process of power battery module is introduced below.

The welding methods applied to the connection of power battery modules mainly include:

1. Resistance welding

Resistance welding is a kind of welding method with resistance heat as energy. Resistance welding uses the resistance heat effect generated by the current flowing through the contact surface and adjacent area of the workpiece to heat it to the molten or plastic state, and pressurize it to form a metal bonding method.

In the group process of power battery, resistance welding, as a relatively mature process, is applied to the welding of power battery monomer and busbar, the connection of power battery lug and parallel conductive strip, etc. Due to the simple equipment and low cost, it is widely used in the early development of power battery industry. In recent years, it has been gradually replaced by more advanced laser welding.

2. Laser welding

Laser welding has high efficiency and is easy to realize automatic production. After continuously improving the welding process and limiting the thermal impact in the forming process, it is more and more used in practical production. Laser welding and industrial robot are gradually becoming the main force of automatic power battery module production line.

HGLASER equipment is cost-effective. With many years of laser R & D experience, the product technology is mature and the product performance is safe and stable.

Laser welding is an efficient and precise welding method using high-energy density laser beam as heat source. Laser welding is mainly used for welding thin-walled materials and low-speed welding. The laser welding process belongs to heat conduction type, that is, laser radiation heats the surface of the workpiece, and the surface heat diffuses to the interior through heat conduction. By controlling the parameters such as laser pulse width, energy, peak power and repetition frequency, the workpiece melts and forms a specific molten pool.

Laser welding process of battery module

1. A method for forming through holes by compounding multi-layer materials, wherein one layer of material is the connecting layer of connecting piece and column, and the multi-layer material laminate ensuring welding performance is used to ensure the conductivity of connecting pad.

2. The substrate of the connecting piece forms a flexible area by laminating multi-layer foil to compensate for the displacement caused by the expansion of the battery unit. The three companies used to reduce the shadow of low-intensity interface are battery module manufacturers. Considering that the solutions to the problems are basically similar, that is, the problems are avoided.

When the welding quality of the two materials cannot be met, different alternative materials shall be used, and the exquisite structure or technology shall be further used to make up for the performance of the exchange materials. Loss. Because this is the optimization space of the welding technology itself, it is very good for the mold base manufacturer.

The above is the application of laser welding machine in the welding process of power battery module. The welding of new energy power lithium battery module is a very key link in the assembly process of new energy battery module. The welding quality will directly affect the product quality. Therefore, laser welding machine is particularly important in the welding process of power battery module.