MANUFACTURING METHOD OF LITHIUM ION SECONDARY BATTERY SEPARATORS, LITHIUM ION SECONDARY BATTERY SEPARATOR AND LITHIUM ION SECONDARY BATTERY

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing method of lithium ion secondary battery separators for efficiently manufacturing short fiber-blended separators and obtaining lithium ion secondary battery separators with high mechanical strength as well as low incidence of internal short circuit failure, and also to provide a lithium ion secondary battery separator manufactured by the manufacturing method and a lithium ion secondary battery comprising the lithium ion secondary battery separator.SOLUTION: Provided is a manufacturing method of lithium ion secondary battery separators for producing a lithium ion secondary battery separator by wet papermaking in which the separator is formed by multiply papermaking with the use of a combination of at least two or more paper machines and by using a suction pickup roll, as a pickup roll, for second and subsequent plies. The invention also provides a lithium ion secondary battery separator manufactured by the manufacturing method and a lithium ion secondary battery comprising the lithium ion secondary battery separator.