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Recently,rare-earth perovskite-type oxides with the general formula ABO3 (A rare earth element,B tran-sition metal,O oxygen) are regarded as promising mate-rials for Ni/oxide batteries due to their hydrogen storage ability.In the present study,the hydrogen storage proper-ties of the rare-earth perovskite-type oxide La0.6Sr0.4 Co0.2Fe0.8O3 were evaluated in alkaline solution and at various temperatures.The hydrogen storage properties were investigated electrochemically by applying galvano-static charge/discharge currents.Electrochemical pressure-composition-temperature isotherms were constructed using the Nst equation.The exchange current density and proton hydrogen diffusion coefficient were calculated using linear polarization measurements and the potential-step method,respectively.Interestingly,the maximum hydro-gen absorption capacity,re-calculated from the electro-chemical capacity,is 1.72 wt％ at 333 K and 6 mol·L-1 KOH.In addition,the hysteresis value,calculated from pressure-composition-temperature isotherms,was 429 J.mol-1 at 333 K,while the self-discharge rate was about 25％ after 24-h storage at open circuit and at 333 K.