3W5W UV laser marks QR code on battery surface, date batch   The production of the battery industry is extremely complicated, because the quality of the battery directly determines the safety of consumers in daily use, so the national regulations for the production and sales of batteries must be traceable to the whole process, that is, including some information such as raw material information, production process and Information such as process, product batch, manufacturer, and production date must be marked and recorded on the battery itself through a QR code.