IMPROVEMENT OF ZINC-BROMINE BATTERY

PURPOSE:To effectively prevent the deposition of dendrite and obtain a zinc- bromine battery with excellent battery efficiency, by adding a trace of nonionic surface active agent acting as a dendrite inhibitor into a negative electrode side electrolytic solution. CONSTITUTION:At the center of an electrolytic cell 1, an ion exchange membrane 4 which partitions the electrolytic cell 1 is provided; while a positive electrode 5 and a negative electrode 6 are disposed respectively on one side and on another side. Around the positive electrode 5, a anolyte solution (ZnBr2-Br2)2 is fed by a pump 11 from a anolyte solution storage tanke 9; while around a negative electrode 6, a catholyte solution (ZnBr2)3 is fed by a pump 12 from a catholyte solution storage tank 10. For instance, 0.01-1.0ml/l of a nonionic surface active agent acting as the dendrite inhibitor is added into catholyte solution 3. The hydrophilic property of this nonionic surface active agent has been enhanced, by reacting a fatty acid ester span of polyoxyethane solbitan with ethylene oxide. This nonionic surface active agent with enhanced hydrophilic property is used.