W-Scope Corp is a Japan-based company mainly engaged in the manufacture and sale of separators for lithium-ion secondary batteries. Microporous membranes made of polyolefin are generally used for the separators of main products, and their role is to separate the positive and negative electrode materials while ensuring lithiumion conductivity between the positive and negative electrodes. In addition, when the battery becomes abnormally hot and reaches a high temperature, the safety mechanism (shutdown property) in which the polyolefin melts and closes the pores plays an important role in stopping the movement of lithium ions and safely stopping the battery's function, responsible for battery safety.