A Horizontal Three-Electrode Structure for Zinc-Air Batteries with Long-Term Cycle Life and High Performance

Limited cycle life is a main reason preventing the large-scale application of electrically rechargeable zinc-air batteries. With the aim of increasing cycle life, a novel three-electrode zinc-air battery in a sandwich arrangement was designed and fabricated. The cycle life was evaluated by charge-discharge cycling tests with 100 cycles at high operational current density (40 mA cm -2 and 80 mA cm -2 for charging and discharging, respectively) for performance testing. A maximum power density of 105 mW cm -2 was achieved at current density of 150 mA cm -2 . The average columbic efficiency, depth of discharge and energy efficiency were 90%, 73% and 42%, respectively. A longer cycling test for 1000 cycles approximately 1917h cycling duration at a current density of 20 mA cm -2 was also achieved and voltage decay for charging and discharging was 13% and 12%, respectively. The results demonstrate that a horizontal tri-electrode structure for zinc-air batteries is advantageous for achieving increased cycle life while exhibiting high power density, high depth of discharge and excellent charge-discharge cycling performance, which provide promising applications of zinc-air batteries for electric vehicle and grid-scale energy storage.