Secondary battery or cell with vitreous carbon coated graphite current collector

Abstract

An improved secondary battery or cell of the type having: (A) an anodic reaction zone containing a molten alkali metal reactant-anode in electrical contact with an external circuit; (B) one or more cathodic reaction zones containing a cathodic reactant which, when said battery or cell is at least partially discharged, is selected from the group consisting of (i) a single phase composition comprising molten polysulfide salts of said anodic reactant and (ii) a two-phase composition comprising molten sulfur and molten sulfur saturated polysulfide salts of said anodic reactant; (C) a cation-permeable barrier to mass liquid transfer interposed between and in contact with said anodic and cathodic reaction zones; and (D) a current collector which at least partially exposed to said cathodic reactant and which is in electrical contact with both said cation-permeable barrier and said external circuit. The improvement comprises employing in said device a current collector comprising a graphite body bearing a coating of vitreous carbon on at least those surfaces thereof which are exposed to said cathodic reactant.

Dependencies are inferred from the claim text.