| 摘要 |
Provided is a battery separator comprising a microporous polyolefin membrane and a modifying porous layer laminated on at least one surface of the microporous polyolefin membrane, wherein the microporous polyolefin membrane comprises a polyethylene resin, and the modifying porous layer is laminated on at least one surface of the microporous polyolefin membrane having (a) a shutdown temperature of 135°C or lower, (b) a rate of air resistance change of 1 × 10 4 sec/100 cc/°C or more, and (c) a transverse shrinkage rate at 130°C of 20% or less. Provided is a battery separator having high physical stability before the start of shutdown, a high rate of air resistance change after the start of shutdown, excellent heat shrinkage resistance in a temperature range from a shutdown start temperature to a shutdown temperature, a low shutdown temperature, and excellent adhesion to electrode. |
