Typical lithium-ion battery recycling methods, such as smelting and acid leaching, have significant disadvantages: Smelting is a high-temperature, energy-intensive process, and both processes generate harmful waste. At the ACS national meeting last week, Jeffrey A. Cunningham of the University of South Florida proposed a greener way to recycle involving fungi. The idea is to promote growth of fungal colonies on pulverized batteries. As these microbes grow, they produce organic acids that would then help leach out the valuable metals from the batteries, making the metals easy to isolate for further processing. Cunningham and his team have identified conditions for quickly growing three candidate strains of fungi, analyzed the organic acids they generate as they multiply, and evaluated the effectiveness of commercial versions of those acids in leaching battery metals. Oxalic acid and citric acid, which are less harsh than common mineral acids, can extract up to 85% of the lithium and nearly half of the cobalt from cathodes of spent batteries. Now, the team plans to study the effectiveness of the fungi-produced versions of the acids, determine how well the fungi tolerate the extracted metals, and evaluate the economic viability of using fungi to recycle battery metals.