An increasing interest continues to be paid to energy-efficient lithium-ion secondary batteries to overcome the exhaustion caused by the excessive use of fossil fuels. In a lithium-ion secondary battery, when discharging, a lithium ion moves from an anode to a cathode, and when charging, a lithium ion moves back from the cathode to the anode to find a place.

Such a lithium ion battery consists of a cathode, an anode, a separator, and an electrolyte, and various materials and combinations are being developed. The manufacturing process of lithium-ion batteries is largely divided into the following three processes.