ARPA–E invests in development of liquid-electrode batteries

MIT Technology Review : In a conventional battery, 75% of its parts don’t contribute to energy storage. And even the best rechargeable commercial batteries take a significant amount of time to fully recharge. The US Department of Energy’s Advanced Research Projects Agency–Energy (ARPA–E) is funding research by four groups into alternative batteries that use liquid electrodes, which would ideally increase the energy storage volume and decrease recharge and refill times. Flow batteries have existed for some time but do not have the energy density to be used in vehicles. Each of the four research groups is attempting to increase that energy density. Two of the groups are using nanoscale powders suspended in liquids as their electrodes and are working to develop ways to extract the energy with high conductivity. One group, which has demonstrated a small battery with one solid and one liquid electrode, is using its funding to develop a fully liquid battery that stores 1 kWh of energy.