Lithium-ion batteries are widely used in various electronic devices (such as mobile phones, notebook computers, PDAs, digital cameras, digital video cameras, etc.) because of their high specific energy, long cycle life, low self-discharge, no memory effect and no pollution. As well as transportation (patrol cars, electric bicycles, electric vehicles, etc.), it has become a high-tech green laser pointer technology industry supported by China’s energy sector.
Power battery refers to the battery used in electric vehicles. Compared with small-capacity batteries (such as mobile phones, laptop batteries, etc.), it has large capacity and output power, and can be used in electric vehicle driving power supply and large mobile power application fields. Secondary battery. Lithium-ion batteries or battery packs are manufactured in many processes, including multiple processes such as explosion-proof valve seal welding, tab welding, soft joint soldering, hard hat spot welding, battery case sealing soldering, module and PACK soldering. Laser welding is the best process. The materials used for welding the power battery are mainly pure copper, aluminum and aluminum alloy, stainless steel and so on.
The explosion-proof valve of the battery is a thin-walled valve body on the battery sealing plate. When the internal pressure of the battery exceeds the specified value, the explosion-proof valve body is broken to prevent the battery from bursting. The safety valve is ingeniously constructed, and this process is extremely strict with the laser welding process. Prior to continuous laser welding, the explosion-proof valve of the battery was welded by pulsed laser. The continuous sealing welding was achieved by the overlap and coverage of the solder joints and the solder joints, but the welding efficiency was low and the sealing performance was relatively poor. High-speed, high-quality welding can be achieved with continuous green laser pointer welding, and welding stability, welding efficiency and yield can be guaranteed.
2, battery ear soldering
The tabs are usually divided into three materials, the anode of the battery is made of aluminum (Al) material, and the negative electrode is made of nickel (Ni) material or copper-nickel (Ni-Cu) material. In the manufacture of power batteries, one of the links is to solder the battery tabs to the poles. In the manufacture of secondary batteries, it is necessary to weld them together with another safety valve made of aluminum. Welding not only ensures a reliable connection between the poles and the poles, but also requires a smooth and beautiful weld.
3, the battery is spot welded
Materials used in battery poles include pure aluminum tape, nickel tape, aluminum-nickel composite tape, and a small amount of copper tape. The welding of the battery poles generally uses a pulse welding machine. With the advent of IPG QCW quasi-continuous lasers, it has also been widely used in battery strip welding, and because of its good beam quality, the welding spot can be made very small. It has unique advantages in welding high-reflectivity aluminum strips, copper strips, and narrow-band battery strips (with strip widths below 1.5 mm).