A non-aqueous all-copper redox flow battery with highly soluble active species

作者：Li, Yun; Sniekers, Jeroen; Malaquias, Joao; Li, Xianfeng; Schaltin, Stijn; Stappers, Linda; Binnemans, Koen; Fransaer, Jan; Vankelecom, Ivo F. J.^*

来源：Electrochimica Acta, 2017, 236: 116-121.

DOI：10.1016/j.electacta.2017.03.039

• Energy storage
• Redox flow battery
• Copper
• Ionic liquids
• Liquid metal salts

A metal-based redox pair with acetonitrile as ligand [Cu(MeCN)(4)][ Tf2N] is described for use in non-aqueous redox flow battery (RFB). The electrode kinetics of the anode and cathode are studied using cyclic voltammetry. The Cu2+/Cu+ and Cu+/Cu couples in this system yield a cell potential of 1.24V. The diffusion coefficient for [ Cu(MeCN)(4)][Tf2N] in acetonitrile is estimated to be 6.8 x 10(-6) cm(2) s(-1) at room temperature. The copper-acetonitrile complex has a very high solubility of 1.68M in acetonitrile, the most widely used organic solvent for non-aqueous electrochemical applications. Hence, a maximum theoretical energy density around 28 Wh L-1 can be reached with the reported system. The RFB with this electrolyte shows a promising performance, with coulombic efficiencies of 87% and energy efficiencies of 44% (5 mA cm(-2)).

• 出版日期2017-5-10
• 单位中国科学院大连化学物理研究所