South Korean battery maker Samsung SDI has started using laser equipment to clean the metal casing used in square power batteries, according to a recent South Korean media report. Prior to 2019, square battery manufacturers such as Samsung SDI did not feel the need to clean these casings, but this has changed with the application of the Z-stacking process and new materials.
As cell production became more complex, it caused a rise in the number of scuffs created during production, which caused the area around the can opening to become dirty and reduced the quality of the top cap welds. Initially, Samsung SDI used cotton with detergent to clean these scratches, but the inefficiency made them look for other more efficient cleaning methods, and laser cleaning was used by Samsung SDI to clean all scratches around the shell and remove other unwanted materials because of its efficiency and environmental benefits.
Samsung SDI is reportedly continuing to develop its fifth-generation battery production process. So far, Z-stacking and label welding have been applied in production, and there are also plans to apply laser technology to the cell notching process with a view to improving cell yields.
What are the specific applications of laser processing technology?
Laser cutting
Before the emergence of laser technology, in the power battery production process, traditional machinery is usually used to process and cut the lugs of the power lithium battery. Traditional die-cutting knife equipment in the process of use, the resulting cutting burr and heat-affected zone is too large, which may affect the performance of the subsequent lithium battery, which may cause various dangerous problems such as battery overheating, short circuit, or even explosion.
Laser cutting has the advantages of no tool wear, flexible cutting shape, edge quality control, higher accuracy and lower operating costs, etc. The cutting effect is better than traditional die-cutting, with small burr and small heat-affected zone, which greatly reduces the safety hazards of lithium batteries, and helps reduce manufacturing costs, improve production efficiency and significantly shorten the die-cutting cycle of new products.
Laser cutting can be mainly applied to the production of battery metal foil slitting, metal foil cutting (lug cutting) and isolation film cutting and other links.
Laser Welding
Power batteries are divided into square, cylindrical and soft pack batteries, the current popularity of square power batteries in the country is relatively high, because of the requirements of the "lightweight" battery cells, the material is generally aluminum alloy, the thickness of the material of mainstream manufacturers are about 0.8 mm, to make these thin materials or fine diameter wire can withstand high strength splicing welding or stack welding, conventional welding process It is difficult to meet the requirements.
Laser welding has a concentrated energy, high welding efficiency, high processing accuracy, welding seam depth to width ratio and can be automated; compared with argon arc welding, resistance welding, ultrasonic welding, etc., the heat input is small, the heat-affected zone is small, the residual stress and deformation of the workpiece is small, less loss of welding material, non-contact processing, higher efficiency, high welding accuracy, safety is also higher, has been used on a large scale for pole lug, core shell, sealing It has been used on a large scale to weld components such as pole lugs, cell shells, sealing nails, flexible connections, explosion-proof valves, battery modules, etc.
Laser cleaning
In addition to the aforementioned Samsung SDI in South Korea before the battery top cover welding cleaning, laser cleaning technology can also be used for lithium battery manufacturing, cell production two parts, such as the electrode coating before, battery assembly process and in addition to the coating process can use laser cleaning, compared to the traditional mechanical scraping, foam adhesive or wet ethanol cleaning process is easy to cause damage to other parts of the lithium battery, laser cleaning technology has a substrate No damage, micron-level precision control, energy saving and environmental protection and many other advantages, can fully meet the battery manufacturing process in a variety of precision cleaning requirements, can greatly improve the battery manufacturing process level.
Power battery as the core components of new energy vehicles, with the gradual explosion of the new energy vehicle market, its production scale will gradually move into the TWh era. According to the "New Energy Vehicle Industry Development Plan (2021-2035)" released by the General Office of the State Council on November 2, 2020, it is expected that by 2025, domestic new energy vehicle sales will reach about 20% of total new vehicle sales. technology is bound to have a huge market potential!
