Biphenyl-lithium-TEGDME solution as anolyte for high energy density non-aqueous redox flow lithium battery

摘要

Non-aqueous redox flow batteries,because of larger operating voltage,have attracted considerable attention for high-density energy storage applications.However,the study of the anolyte is rather limited compared with the catholyte due to the labile properties of redox mediators at low potentials.Here,we report a new strategy that exploits high concentration organic lithium metal solution as a robust and energetic anolyte.The solution formed by dissolving metallic lithium with biphenyl (BP) in tetraethylene glycol dimethyl ether (TEGDME) presents a redox potential of 0.39V versus Li/Li+,and a concentration up to 2 M.When coupled with a redox-targeted LiFePO4 catholyte system,the constructed redox flow lithium battery full cell delivers a cell voltage of 3.0V and presents reasonably good cycling performance.