In zinchydrogen peroxide batteries, an active metal - zinc piece is used as the anode and ammonium chloride is used as the electrolyte in the anode zone. A soluble oxidant, hydrogen peroxide, is used as the active cathode substance, and sulfuric acid as an electrolyte in the cathode zone. Carbon felt, the sum of two apparent areas of which is 24?cm2, is used as an inert cathode with a PE-01 homogeneous membrane between the anode and cathode zones and 50?mL of solution in both the anode and cathode zones. The discharge characteristics of the batteries at 5?O were investigated for various concentrations of hydrogen peroxide, sulfuric acid and ammonium chloride solutions. When a 5-M ammonium chloride solution was used in the anode zone with a 3.2-M sulfuric acid and 3.52-M hydrogen peroxide mixed solution in the cathode zone, an average discharge current of 190?mA, an average output voltage of approximately 0.95?V and an actual gravimetric energy density of 42.73?W?h?kg-1 were obtained, and the discharge time of the batteries was more than 30?h. Copyright (c) 2011 John Wiley & Sons, Ltd.