TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Materials: In (I), the metal A is alkali metal such as sodium, potassium and/or silver, and x (lithium substitution quantity of metal A) is 0.03-0.2. The composite oxide is (II) or (III):where M is metal substituting a part of manganese, and y (manganese substitute quantity of metal M at manganese sites) is 0-1, preferably 0.03-0.5. x is equal to a ratio a/b, where a, b = 1-30. b is greater than a. y is equal to a ratio c/d, where c, d = 1-30. d is greater than c. The composition variation of x or y is +/-5%. When M is not manganese, then the metal M comprises transition metals and/or metallic elements such as cobalt, nickel, chromium, iron, aluminum, gallium and/or indium.The negative electrode (2) comprises lithium metal, composite oxide, nitride and/or carbon. EXAMPLE - Lithium hydroxide monohydrate powder, dimanganese trioxide powder, univalent metal compound, and compound of manganese-site substitute metal were weighed at a predetermined mole ratio, and mixed in a mortar. The mixture was heat treated at 900 degrees C for 24 hours in argon atmosphere, cooled and the obtained calcined product was crushed.    A positive electrode material of formula (IV) comprising sodium nitrate as univalent metal compound, was obtained.    The obtained positive electrode material was mixed with acetylene black as conducting material and poly tetra fluoroethylene (PTFE) powder as binding material at a weight ratio of 80:16:4. The mixture was molded into a circular disc having a diameter of 12 mm. The molded mixture was heat treated at 150 degrees C for 16 hours to produce a disc-shaped positive electrode (1). Then, a negative electrode member was formed by compressing lithium metal in the shape of a circular disc having diameter of 12 mm and mesh-shaped negative electrode collector plate of stainless steel.    A solution of combined solvent obtained by mixing ethylene carbonate and diethyl carbonate at a volume ratio of 1:1, and 1 mol/l of LiPF6 were dissolved in the combined solvent to form an electrolyte. A polypropylene film was used as a separator (3). Stainless steel (SUS) sheet was used as positive electrode collector. Leads were taken out from positive and negative electrodes. An element was formed by placing the electrode members across the separator, and pressed. The element was interposed between PTFE plates, and a sealed non-aqueous battery was formed. The number of charge-discharge cycles of the battery when its discharge capacity decreased below 90% of the initial discharge capacity, was evaluated and found to be 131.