SEPARATOR FOR NONAQUEOUS ELECTROLYTE BATTERIES, AND NONAQUEOUS ELECTROLYTE BATTERY

摘要

Provided herein is a nonaqueous electrolyte battery separator capable of rendering a battery flame-retardant and suppressing a reduction in battery performance is provided. A porous front-side protective layer 47 is formed on a front surface 45A of a porous base material 45 made of a polyolefin-based resin. The front-side protective layer 47 protects the porous base material 45 such that the porous base material 45 is not thermally deformed or thermally contracted. A porous front-side flame retardant layer 49 is formed on the front-side protective layer 47. The front-side flame retardant layer 49 contains solid flame retardant having a melting point lower than the ignition temperature of a nonaqueous electrolyte.