METHOD FOR MANUFACTURING SECONDARY BATTERY AND SECONDARY BATTERY

According to the present disclosure, there is provided a technique making it possible to prevent an electrode active material layer and a protective layer from falling off or peeling off at the laser cutting site of an electrode plate and to obtain a highly safe secondary battery. A manufacturing method disclosed herein includes a step of preparing a positive electrode precursor having a positive electrode active material layer and a protective layer applied to a surface of a positive electrode core, and a step of cutting a protective layer application region of the positive electrode precursor by a continuous wave laser. As a result, it is possible to prevent the protective layer from falling off or peeling off due to the impact during laser irradiation. The manufacturing method disclosed herein also includes a step of preparing a negative electrode precursor having a negative electrode active material layer applied to a surface of a negative electrode core, and a step of cutting a negative electrode active material layer application region of the negative electrode precursor by a pulsed laser. As a result, the amount of melted negative electrode core can be reduced when the negative electrode precursor is cut, so that it is possible to prevent the formation of a negative electrode active material layer mixed with molten metal, which is likely to fall off or peel off from the negative electrode core.