A process for making an electrode sheet for a solid lithium electrochemical cells is disclosed. The process comprises the steps of: a) admixing a polyether polymer or copolymer, at least one lithium salt, at least one electrochemically active material and purified water to form an aqueous solution/suspension containing by weight at least 40% purified water, at least 20% active electrode material, up to 10% electrically conductive material, at least 5% polyether polymer or copolymer, and at least 1.5% lithium salt; b) coating the aqueous solution/suspension in the form of an electrode thin film onto an electrode support; and, c) evaporating the water from the electrode thin film to obtain an electrode sheet having less than 1000 ppm of residual water. The evaporation step is preferably carried out through a dryer/oven tunnel having incremental drying zones.