A solid electrolyte primary cell comprising a lithium anode, a bromine cathode and a lithium bromide electrolyte. A solid lithium element operatively contacts the cathode material, and one form of cathode material is a charge transfer complex of an organic donor component material and bromine. The organic donor component material can be poly-2-vinyl pyridine. Another cathode material is liquid bromine. The surface of the lithium anode element which operatively contacts the cathode material can be provided with a coating of an organic electron donor component material. When the lithium anode operatively contacts the bromine cathode, a solid lithium bromide electrolyte begins to form at the interface and an electrical potential difference exists between conductors operatively connected to the anode and cathode.