An anhydrous inorganic gel-polymer electrolyte is prepared using a non-aqueous sol-gel process. The inorganic gel-polymer is prepared by reacting a metal halide (SiCl4) and an alcohol (tert-butyl alcohol) in a diluent solution containing a lithium salt (lithium bisperfluoroethanesulfonimide) and at least one carbonate. The resulting porous silicon oxide network encapsulates the liquid electrolyte. The gel polymer electrolyte can serve as both a separator and an electrolyte in a Li-ion cell. The material is stable and has demonstrated minimal flammability. Lithium-ion electrochemical cells made with the inorganic gel-polymer electrolyte function similarly to Li-ion cells made with a liquid electrolyte. The cells have low capacity fade, 0.69%, and low irreversible capacity, 7.6%.