abstract |
This invention relates to separators for batteries and other electrochemical cells, especially lithium-ion batteries, having a shutdown mechanism. The separator comprises a nonwoven nanoweb comprising a coating composed of a plurality of thermoplastic particles having particle size larger than the mean flow pore size of the nanoweb. The coating flows at a desired temperature, and restricts the ion flow path, resulting in a substantial decrease in ionic conductivity of the separator at the desired shutdown temperature, while leaving the separator intact. |