Lithium cell with iron disulfide cathode and improved electrolyte

A primary cell having an anode comprising lithium and a cathode comprising iron disulfide (FeS2) and carbon particles. The electrolyte comprises a lithium salt dissolved in a solvent mixture which contains 1,3-dioxolane and isosorbide dimethyl ether. The solvent mixture may comprise 1,3-dioxolane, 1,2-dimethoxyethane and additive isosorbide dimethyl ether. The isosorbide dimethyl ether comprises typically between about 2 and 15 percent by weight of the solvent mixture and improves cell service life and performance. A cathode slurry is prepared comprising iron disulfide powder, carbon, binder, and a liquid solvent. The mixture is coated onto a conductive substrate and solvent evaporated leaving a dry cathode coating on the substrate. The anode and cathode can be spirally wound with separator therebetween and inserted into the cell casing with electrolyte then added.