What\u2019s not to like?\u00a0 Until now, they\u2019ve been difficult to recharge.\u00a0 ReVolt tried developing a rechargeable zinc-air battery<\/a> with an ARPA-E (Advanced Research Projects Agency \u2013 Energy) grant, but gave up after two years. Explaining that the zinc-air batteries used in hearing aids were not rechargeable, ReVolt attempted to prevent the growth of dendrites, little follicles that eventually punch through the internal separators and cause short circuits.<\/p>\n Workings of a rechargeable zinc battery. \u00a0Sydney researchers managed simultaneous control of the composition, size and crystallinity of metal oxides of earth-abundant elements such as iron, cobalt and nickel<\/p><\/div>\n Stanford scientists had investigated a high-energy zinc-air battery in 2013<\/a>.\u00a0 Hongjie Dai, a professor of chemistry at Stanford and the lead author of a study published at the time, said, “Metal-air batteries offer a possible low-cost solution.”\u00a0 He added, \u201c”With [an] ample supply of oxygen from the atmosphere, metal-air batteries have drastically higher theoretical energy density than either traditional aqueous batteries or lithium-ion batteries.\u00a0 Among them, zinc-air is technically and economically the most viable option.”<\/p>\n A lack of electrocatalysts that successfully reduce and generate oxygen during the discharging and charging of a battery have kept these potentially high-potential cells from success.\u00a0 But the paper published in the August 14 on-line edition of Advanced Materials<\/a>, explains how the Sydney team and their partners at Nanyang Technological University developed a new three-stage method to overcome this problem and create an oxygen electrocatalyst at the heart of the research.<\/p>\n![\"\"](\"http:\/\/sustainableskies.org\/wp-content\/uploads\/2017\/08\/zin-720x540-528x396.gif\")