A non-aqueous electrolyte is disclosed. Exemplary embodiments include at least one ionically conducting salt, especially a lithium salt, a non-aqueous, anhydrous solvent for the ionically conductive salt, the solvent being selected to achieve a degree of dissociation of the ionically conductive salt in the non-aqueous solvent, at least one oxide in a particulate form, the oxide being selected such that it is not soluble in the solvent and such that it is water-free. The electrolyte can be used in a primary or secondary lithium battery, in a supercapacitor, in an electro-chromic display or in a solar cell.