Chinese researchers unveiled a breakthrough development in energy storage—a novel zinc-bromine flow battery. A research team led by Professor Li Xianfeng from the Dalian Institute of Chemical Physics, Chinese Academy of Sciences, engineered an innovative system featuring two-electron transfer based on bromine. This technology fundamentally alters bromine’s behavior within the cell, resolving a major issue in such setups: the accumulation of corrosive elemental bromine during charging, which causes component degradation and shortens operational life. The scientists proposed a fundamentally new chemical reaction by introducing amine compounds into the electrolyte, which bind the bromine. Consequently, bromine does not accumulate as free, aggressive element but is converted into brominated amine compounds. The concentration of elemental bromine in the electrolyte is maintained at an ultra-low level, sharply decreasing the system’s corrosive activity. This not only boosts safety but also significantly extends the battery’s service life. Due to the ultra-low bromine concentration, the battery operated steadily utilizing a standard non-fluorinated ion-exchange membrane, eliminating the need for costly corrosion-resistant materials and lowering system expense. During testing on a scaled five-kilowatt system, the accumulator demonstrated remarkable consistency, functioning for over 700 cycles at a current density of 40 milliamperes per square centimeter. The device’s energy efficiency surpassed 78%. Subsequent examination of key parts—electrodes, current collectors, and membranes—showed no signs of corrosion following extensive cycling. This innovation paves the way for building more durable, safer, and cost-effective energy storage solutions for power grids.
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