Patent ID: 8932509
Filing Date: 2015-01-13
Classification: B01D,H01B,H01M,Y02E,Y02P

Abstract:
1. A method of producing a solid electrolyte membrane, the method comprising steps of: (a) casting a dope containing a solid electrolyte and an organic solvent from a casting die onto a running support so as to form a casting membrane; (b1) drying an exposed surface side of the casting membrane by applying dry air having a velocity of less than 3 m/s so as to form a skin layer as part of said casting membrane at the exposed side surface, a thickness of the skin layer after a lapse of 60 seconds from said casting being in a range from 2% to 40% of that of the casting membrane as a whole, and the skin layer having a surface tension different from that of a support side of the casting membrane; (b2) separately drying the casting membrane having said skin layer by applying dry air having a velocity higher than the velocity of dry air applied in said step (b1) so as to provide the casting membrane having said skin layer with a self-supporting property; (c) peeling the self-supporting casting membrane from the support as a wet membrane containing said organic solvent; (d) drying the wet membrane so as to form said solid electrolyte membrane; and (e) bringing the wet membrane before said step (d) into contact with a liquid having a boiling point lower than that of said organic solvent, the liquid being a poor solvent of the solid electrolyte.