As one of the supporting technologies for advanced manufacturing, pulsed lasers, with their high precision, low thermal distortion, high efficiency and short cycle times, are making a splash in applications such as automotive, electronics, aerospace, photovoltaics and consumer goods, where they are playing an increasingly important role in improving product quality, processing efficiency, as well as reducing consumables and saving energy. Pulsed lasers therefore play an important role in the development of high-end precision manufacturing in China, and are an important area of concern to the world.
Currently, pulsed lasers are mainly used for cutting, marking, engraving and drilling, with laser cleaning being a slightly less popular application. The main mechanism of laser cleaning is similar to that of laser marking. The thermal expansion causes the contaminant or the substrate to vibrate, thus causing the contaminant to overcome the surface adsorption force from the substrate surface and subsequently removing the stain.
Today, as laser cleaning technology has made great strides, many laser manufacturers are deeply expanding more areas of application, multi-point efforts to make it a new market growth point, especially in new energy vehicles, semiconductors, 5G and other fields, the use of laser cleaning is significant.
As the key performance of new energy vehicles, such as range and safety, is closely related to the power battery, as a core component, the power battery has very high requirements for production equipment. The manufacturing process can be divided into three parts: cell manufacturing, cell production and battery assembly, in which many laser processes are applied, such as cell cutting, lug cutting, case marking and laser cleaning. Pulsed laser cleaning is mainly used in the back-end of the assembly process, i.e. laser cleaning before battery welding to remove dirt, metal debris, dust, etc. from the end face of the electrode column, in advance of battery welding, to improve the overall quality of welding and enhance the battery manufacturing process.
As the copper and aluminium used for the positive and negative metal materials of the power battery have exactly the same high anti-reflective properties, the 355nm UV nanosecond laser developed and designed by Nuffield Optoelectronics is able to achieve very good cleaning results. Firstly, most materials have a high absorption rate of UV light, copper and aluminium still have a high absorption rate at a wavelength of 355nm, coupled with the high single photon energy of UV light and high repetition frequency of up to 100KHz, removing surface materials more efficiently, while its stable pulse sequence can meet the 7*24 hours operation on the power battery production line, very much in line with the strong demand for power battery production capacity.
In addition, laser processing without consumables and pollution is also particularly in line with the current green energy-saving environmental mainstream, but also the future trend of industrial development. Laser cleaning, as a green cleaning technology, is expected to enhance the development potential with the rapid development of the new energy vehicle market.
