NOVELTY - A battery comprises a cathode (16) including a high energy density material having an intercalating ion, redox-couple ion, and an anion.    USE - Used as an electrical energy source.    ADVANTAGE - The battery has improved energy density.    DETAILED DESCRIPTION - A battery comprises a cathode including a high energy density material having an intercalating ion (A'), redox-couple ion (B'), and an anion (C'), where A', B', and C', are present in an stoichiometric amount to satisfy the relationship cZc=aZa + bZb, and provide theoretical energy density of greater than 630 Wh/kg, an ion diffusion constant of greater than 1x10-15 cm2/s, and disproportionation characteristics that satisfy the ionization relationship, I-B'-m is greater than I-A'-n, where I-B'-m= mth ionization potential of the redox-couple ion and I-A'-n=nth ionization potential of the intercalating ion, where A' and B'= titanium, vanadium, chromium, manganese, iron, cobalt, nickel, aluminum, gallium, zirconium, niobium, or molybdenum, and C=anion from an oxide, hydroxide, sulfide, phosphide, carbide, silicate, ortho-silicate, meta-silicate, pyrosilicate, soro-silicate, cyclo-silicate, ino-silicate, phyllo-silicate, phosphate, phospite, pyro-phosphate, poly-phosphate, ortho-phosphate, soro-phosphate, cyclo-phosphate, ino-phosphate, phylo-phosphate, oxygen defective phosphates, borate, carbonate, aluminate, zeolite, vanadate, titanate, ortho-titanate, molybdate, chromate, zirconate, ortho zirconate, stagnate, ferrate, ceria, barium, chlorate, chlorite, hypo-chlorite, zincate or clathrates. INDEPENDENT CLAIMS are included for:    (1) a method of producing a battery;    (2) a material for electrochemical energy storage;    (3) a method of producing a material;    (4) an electrode for an electrochemical device; and    (5) a method of producing an electrode.    DESCRIPTION OF DRAWING(S) - The figure is a cross-sectional view of a cell.    Anode (12)    Cathode (16)    Crown (18)    Separator (20)    Contact (24)