a method of converting and storing energy in a repeatable cycle using a rechargeable electrolytic cell providing a thermal energy output during discharge , and which recharges electrically . the cell contains chemical reactants and reactant product . the reactant product is electrolyzed into the reactants by at least one electrode in operational communication with the reactant product . the electrode has a porous portion , and one of the reactants , the oxidizer , is conveyed through the porous portion of the electrode , without conveying the reactant product through it , into a hollow internal cavity in the electrode . the reactants are separated and stored in the cell . the stored reactants are controllably combined to produce the reactant product and the thermal energy output . the thermal energy is removed from the cell for useful purposes .