a highly conductive polymer based solid gel membrane is disclosed . the membrane is especially well suited for use in such electrochemical devices as , for example , aluminum / air , zinc / air , zn / mno 2 , ni / cd and hydrogen fuel cells , as well as in electrochromic devices such as smart windows and flat panel displays . in accordance with the principles of the invention , anion - and cation - conducting membranes are formed . the gel composition of the membrane contains the ionic species within its solution phase such that the species behaves as in a liquid electrolyte , while at the same time , the solid gel composition prevents the solution phase from diffusing into the device . methods of forming polymer based solid gel membranes of the present invention are also disclosed .