NOVELTY - A storage cell (20) comprises a negative electrode (19) comprising liquid alkali metal (16), a positive oxygen electrode (18) and a dense alkali metal cation-conductive solid electrolyte (12) which is positioned between the negative electrode and porous matrix (10), and which is formed using a secondary mixed metal oxide which conducts the alkali metal cation. The positive oxygen electrode comprises a porous mixed metal oxide matrix, a dense separation element formed using primary mixed metal oxide which conducts oxygen ions and electrons, and a source of oxygen-containing gas.    USE - Storage cell e.g. rechargeable cell is used in battery used for generating energy (all claimed) including electric vehicle propulsion, and for hybrid fuel cell battery for electric vehicle.    ADVANTAGE - The storage cell has excellent mechanical strength and crack resistance. The battery comprising the storage cell has excellent cycle characteristics.    DETAILED DESCRIPTION - A storage cell comprises a negative electrode comprising liquid alkali metal, a positive oxygen electrode and a dense alkali metal cation-conductive solid electrolyte which is positioned between the negative electrode and the porous matrix, and which is formed using a secondary mixed metal oxide which conducts the alkali metal cation. The positive oxygen electrode comprises a porous mixed metal oxide matrix, a dense separation element formed using primary mixed metal oxide which conducts oxygen ions and electrons, and a source of oxygen-containing gas. The dense oxygen ion- and electron-conducting separation element is provided between the porous matrix and the source of oxygen-containing gas. The porous matrix of the positive electrode is positioned between the solid electrolyte and the dense mixed metal oxide separator element for receiving oxygen anions and alkali metal cations, and is not in direct contact with the oxygen-containing gas or liquid alkali metal. The porous matrix is formed using the primary and secondary mixed metal oxides. The porous matrix comprises region(s) which conducts the alkali metal cation and the oxygen anions, in which the alkali metal and the oxygen ions are reacted to form discharge product retained within the porous matrix. An INDEPENDENT CLAIM is included for production of storage cell.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the storage cell.    Porous matrix (10)    Solid electrolyte (12)    Liquid alkali metal (16)    Positive oxygen electrode (18)    Negative electrode (19)    Storage cell (20)