Abstract:
Disclosed is an alkali-ion conducting separator assembly comprising a porous membrane (A) and an alkali-ion conducting film (B) placed on one major surface of the porous membrane (A), wherein the alkali-ion conducting film (B) comprises an inorganic material of the general formula (I): (L1+ [(12-u )2+wv)-xm-[(3-y)3+yn]-[(2-z)5+zp]Im+ x](A3+ 3-ya n+ y)(B5+ 2-zbp+ z)(O2- 12-uDv- w) (I) Further disclosed is a process for producing such an alkali-ion conducting separator assembly and a rechargeable electrochemical cell comprising such an alkali-ion conducting separator assembly.