Enhanced zinc electrode rechargeability in alkaline electrolytes containing hydrophilic organic materials with positive electrode compatibility

Enhancing zinc electrode rechargeability is a key for realizing zinc air batteries as promising next generation batteries. Addition of hydrophilic organic materials in alkaline electrolytes has been shown to be effective in durability improvement, however, the oxidation of the organic materials at the positive electrode of batteries should be overcome. Here a solution for this issue is proposed by using organic materials with large molecular weight and keeping them away from the positive electrode by setting a membrane between negative and positive electrodes. It is shown through permeability, solubility, and zinc-nickel cell tests that a selected organic material is impermeable to a OH^- permeable membrane, highly soluble in the alkaline electrolyte, and has a positive effect on zinc electrode durability without interfering the positive electrode reaction, which can greatly contribute to the establishment of long-life zinc air batteries.