Hydrophilic microporous film

Claim 2

IN A BATTERY COMPRISING AT LEAST ONE ELECTROLYTIC CELL, SAID CELL INCLUDING AN ANODE AND A CATHODE DISPOSED INAN ELECTROLYTE SAID ANODE AND CATHODE SEPARATED IN SAID ELECTROLYTE BY A BATTERY SEPARATOR THE IMPROVEMENT COMPRISING THE BATTERY SEPARATOR, SAID SEPARATOR COMPRISING A HYDROPHOBIC, MICROPOROUS POLYMERIC FILM CHARACTERIZED BY A REDUCED BULK DENSITY COMPARED TO THE BULK DENSITY OF THE CORRESPONDING NON-POROUS PRECURSOR FILM, A CRYSTALLINITY OF ABOVE ABOUT 30 PERCENT, AN AVERAGE PORE SIZE OF ABOUT 100 TO 12,000 ANGSTROMS, A SURFACE AREA OF ABOUT 2 TO ABOUT 200 SQUARE METERS PER GRAM, AND A VOID VOLUME OF BETWEEN ABOUT 20 TO 45 PERCENT; AND A SURFACTANT COATING COMPRISING ABOUT 2 TO 20 PERCENT BY WEIGHT OF THE UNCOATED MICROPOROUS FILM, OF POLYOXETHYLENE POLYMETHYL SIOXANE.

Claim 3

In a battery comprising at least one electrolytic cell, said cell including an anode and a cathode disposed in electrolyte, said anode and cathode separated in said electrolyte by a battery separator the improvement comprising the battery separator, said separator comprising a hydrophobic, microporus, polymeric film characterized by a reduced bulk density compared to the bulk density of the corresponding non-porous precursor film, a crystallinity of above about 30 percent, an average pore size of about 100 and 12,000 Angstroms, a surface area of about 2 to about 200 square meters per gram, and a void volume of about 20 to 45 percent; and a surfactant coating comprising about 2 to 20 percent, by weight of the uncoated microporous film, said coating comprising a mixture of a polyoxethylene polymethyl siloxane and an imidazoline tertiary amine.

Claim 4

In a battery comprising at least one electrolytic cell, said cell including an anode and a cathode disposed in electrolyte, said anode and cathode separated in said electrolyte by a battery separator the improvement comprising the battery separator, said separator comprising a hydrophobic, microporus, polymeric film characterized by a reduced bulk density compared to the bulk density of the corresponding non-porous precursor film, a crystallinity of above about 30 percent, an average pore size of about 100 and 12,000 Angstroms, a surface area of about 2 to about 200 square meters per gram, and a void volume of about 20 to 45 percent; and a surfactant coating comprising about 2 to 20 percent, by weight of the uncoated microporous film, said coating comprising a mixture of a polyoxethylene polymethyl siloxane and an imidazoline tertiary amine.