A primary cell having an anode comprising lithium or lithium alloy and a cathode comprising iron disulfide (FeS2) with calcium hydroxide Ca(OH)2 and lithium carbonate Li2CO3 additive mixed therein. The electrolyte may typically comprise lithium bistrifluoromethylsulfonyl imide, Li(CF3SO2)2N (LiTFSI) salt dissolved in a solvent mixture comprising 1,3-dioxolane and sulfolane. The electrolyte typically contains between about 100 and 2000 parts by weight water per million parts by weight (ppm) electrolyte therein. A cathode slurry is prepared comprising iron disulfide powder with Ca(OH)2 and Li2CO3 mixed therein, 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.