An aqueous composition [composition] for use in the preparation of coated separators for electrochemical devices comprising: i) at least one salified polyamide-imide polymer (PAI-Salt) comprising more than 50% by moles of recurring units R PAI selected from the group consisting of units of any of general formulae (R PAI -a) (R PAI -b) and (R PAI -c): provided that R PAI -c represents at least 30 % by moles of recurring units in the lithiated polyamide-imide (LiPAI), wherein: - Ar is a trivalent aromatic group; preferably Ar is selected from the group consisting of the following structures: and corresponding optionally substituted structures, wherein X is selected from the group consisting of -O-, -C -, -CH 2 -, -C(CF 3) 2 -, -(CF 2) n -, with n being an integer from 1 to 5; X is selected from the group consisting of -O-, -C -, -CH 2 -, -C(CF 3) 2 -, and -(CF 2) p -; n is an integer from 1 to 5; R is a divalent aromatic group selected from the group consisting of: and corresponding optionally substituted structures, and Y is selected from the group consisting of -O-, -S-, -SO 2 -, -CH 2 -, -C -,-C(CF 3) 2 -, -(CF 2) q -, q being an integer from 0 to 5; and Cat + is a monovalent cation preferably selected from alkali metals cations, more preferably is selected from Na +, K+ and Li +, even more preferably is Li +; ii) an aqueous dispersion comprising at least one aqueous medium and at least one vinylidene fluoride polymer [polymer] under the form of primary particles having an average primary particle size of less than 1 μm, as measured according to ISO 22412 [latex]. i) at least one salified polyamide-imide polymer (PAI-Salt) comprising more than 50% by moles of recurring units R PAI selected from the group consisting of units of any of general formulae (R PAI -a) (R PAI -b) and (R PAI -c): provided that R PAI -c represents at least 30 % by moles of recurring units in the lithiated polyamide-imide (LiPAI), wherein: - Ar is a trivalent aromatic group; preferably Ar is selected from the group consisting of the following structures: and corresponding optionally substituted structures, wherein X is selected from the group consisting of -O-, -C -, -CH 2 -, -C(CF 3) 2 -, -(CF 2) n -, with n being an integer from 1 to 5; X is selected from the group consisting of -O-, -C -, -CH 2 -, -C(CF 3) 2 -, and -(CF 2) p -; n is an integer from 1 to 5; R is a divalent aromatic group selected from the group consisting of: and corresponding optionally substituted structures, and Y is selected from the group consisting of -O-, -S-, -SO 2 -, -CH 2 -, -C -,-C(CF 3) 2 -, -(CF 2) q -, q being an integer from 0 to 5; and Cat + is a monovalent cation preferably selected from alkali metals cations, more preferably is selected from Na +, K+ and Li +, even more preferably is Li +; provided that R PAI -c represents at least 30 % by moles of recurring units in the lithiated polyamide-imide (LiPAI), wherein: - Ar is a trivalent aromatic group; preferably Ar is selected from the group consisting of the following structures: - Ar is a trivalent aromatic group; preferably Ar is selected from the group consisting of the following structures: and corresponding optionally substituted structures, wherein X is selected from the group consisting of -O-, -C -, -CH 2 -, -C(CF 3) 2 -, -(CF 2) n -, with n being an integer from 1 to 5; X is selected from the group consisting of -O-, -C -, -CH 2 -, -C(CF 3) 2 -, and -(CF 2) p -; n is an integer from 1 to 5; R is a divalent aromatic group selected from the group consisting of: and corresponding optionally substituted structures, and Y is selected from the group consisting of -O-, -S-, -SO 2 -, -CH 2 -, -C -,-C(CF 3) 2 -, -(CF 2) q -, q being an integer from 0 to 5; and Cat + is a monovalent cation preferably selected from alkali metals cations, more preferably is selected from Na +, K+ and Li +, even more preferably is Li +; ii) an aqueous dispersion comprising at least one aqueous medium and at least one vinylidene fluoride polymer [polymer] under the form of primary particles having an average primary particle size of less than 1 μm, as measured according to ISO 22412 [latex].