Zothecula (1870348) writes "A flow battery is a rechargeable fuel cell that pumps a solution of charged metals dissolved in an electrolyte through a membrane to convert chemical energy into electricity. Flow batteries can be rapidly "recharged" by replacing the electrolyte liquid while simultaneously recovering the spent material for external recharging. Researchers at the U.S. Department of Defense's Sandia National Laboratories have discovered a new family of metal-based liquid salt electrolytes, for use in just such flow batteries. The electrochemically reversible Metal-based Ionic Liquids (MetILs) could lead to batteries packed with 3-10 times the energy density of other available storage technologies."
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