A rechargeable zinc-air battery based on zinc peroxide chemistry
Wei Sun, Fei Wang, Bao Zhang, Mengyi Zhang, Verena Küpers, Xiao Ji, Claudia Theile, Peter Bieker, Kang Xu, Chunsheng Wang, Martin Winter
Abstract
When two is better than four Batteries based on the reaction of zinc and oxygen have been used for more than a century, but these have been primary (that is, nonrechargeable) cells. These batteries use an alkaline electrolyte and require a four-electron reduction of oxygen to water, which is a slow process. Sun et al. show that with the right choice of nonalkaline electrolyte, the battery can operate using a two-electron zinc-oxygen/zinc peroxide chemistry that is far more reversible. By making the electrolyte hydrophobic, water is excluded from the near surface of the cathode, thus preventing the four-electron reduction. These batteries also show higher energy density and better cycling stability. Science , this issue p. 46