POROUS FILM MATERIAL, COMPRISING AT LEAST ONE CARBONACEOUS SEMIMETAL OXIDE PHASE, AND THE USE THEREOF AS A SEPARATOR MATERIAL FOR ELECTROCHEMICAL CELLS

摘要

The present invention relates to a novel porous film material which comprises at least one carbonaceous semimetal oxide phase, and to a process for production thereof. The invention also relates to the use of these porous film materials as a separator layer or for production of such separator layers in electrochemical cells, particularly in lithium cells and especially in lithium secondary cells. The inventive porous film material comprises: a) at least one carbonaceous (semi)metal oxide phase A of silicon, of aluminum, of titanium or of zirconium, which has hydrocarbon groups bonded covalently to the (semi)metal of said (semi)metal oxide phase A; b) optionally one or more organic polymer phases B, said carbonaceous (semi)metal oxide phase A forming essentially continuous phase domains in which the pore phase present in the film material and the optionally present organic polymer phase(s) B are intercalated, the mean distance between two phase boundaries of adjacent domains of identical phases being not more than 50 nm, preferably not more than 10 nm, particularly not more than 5 nm and especially not more than 2 nm.