NOVELTY - The system (30) has a hydrogen storage unit (12) that stores the hydrogen produced by electrolysis and supplies the stored hydrogen to electric power generation unit at the time of the electric power generation. A high temperature thermal storage part (13) stores heat generated by the said electric power generation, and supplies generated heat to electrolysis unit at the time of electrolysis. A low-temperature thermal storage unit (31) generates the water vapor to be supplied to electrolysis unit by using the low temperature heat.    USE - Hydrogen electric power storage system for generating electric power used for air conditioning application.    ADVANTAGE - As the heat generated at the time of electric power generation is utilized effectively, the storage efficiency of the electric power is improved.    DETAILED DESCRIPTION - The electric power generation unit and electrolysis unit are provided with solid electrolyte fuel cell that functions as fuel cell and water vapor electrolysis cell. The solid electrolyte fuel cell and the electrolysis unit are provided with solid oxide electrolyte. The regenerator container has a flow path of heat-medium fluid flowing around the capsule. Two ceramic portions are joined through the joining layer consisting of silicon layer formed by heating the carbon layer and ceramic layer that is formed by heating ceramic precursor and carbon adhesive agent. A silicon phase is formed in the clearance gap between silicon carbide particles. The carbon reacts with melting silicon and to produce silicon carbide particle. The porous structure is positioned between two ceramic portions. The average particle diameter of silicon carbide powder is set about 0.5-5 mu m. The average particle diameter of carbon powder is set about 0.3-3 mu m. The viscous material containing the hardening agent is made into solidified structure, after hardening the room-temperature-curing type resin at room temperature. INDEPENDENT CLAIMS are included for the following:    (1) hydrogen electric power storage method;    (2) ceramic joining material, which includes mixture containing the silicon carbide powder, carbon powder and room-temperature-curing type resin that has specific viscosity and adhesiveness. The ceramic joining material has hardening agent that hardens the mixture. The volume ratio of the silicon carbide powder with respect to all the powder constituents in the joining material is set to 18-60%. The total mass ratio of the silicon carbide powder and the carbon powder is set to 29-55% of the whole viscous material; and    (3) manufacturing method of ceramic composite material, which involves molding material which has solidified structure of viscous material obtained by hardening the room-temperature-curing type resin. The heat-processing is performed with respect to molded material. The melting silicon is impregnated to solidified structure of viscous material. The ceramic composite material having silicon carbide-carbon composite component is produced. The average air hole diameter of the solidified structure is set about 0.5-5 mu m.    DESCRIPTION OF DRAWING(S) - The drawing shows a block diagram of the hydrogen electric power storage system. (Drawing includes non-English language text)    Electric power/hydrogen converter (11)    Hydrogen storage unit (12)    High-temperature thermal storage unit (13)    Hydrogen electric power storage system (30)    Low-temperature thermal storage unit (31)