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Advanced Bi-Additive Vanadium Electrolyte

Tuesday, 15 May 2018
Ballroom 6ABC (Washington State Convention Center)
Z. Nie (Pacific Northwest National Laboratory), W. Wang (Joint Center for Energy Storage Research (JCESR)), V. Murugesan, X. Wei (Joint Center for Energy Storage Research), B. Li (Pacific Northwest National Laboratory), J. Liu (Joint Center for Energy Storage Research (JCESR)), and V. Sprenkle (Pacific Northwest National Laboratory)
New all vanadium with bi-additive electrolyte has 30% higher energy density and 80% wider temperature window which will be a promising energy storage option for the future grid. The solubility of the vanadium ions was improved to 2.0M, in a much wider temperature range from -5 to 50⁰C.

Our new bi-additive system containing (NH4)2HPO4 increases the V5+ intermolecular distance from ~5 angstrom to ~8 angstrom which has greatly improved the V5+ electrolyte stability and solubility. Based on the computer simulation results, two V5+ molecular will form complex with one HPO4 which will significantly increase the distance between the two V5+ molecular.

. With the new vanadium electrolyte, we demonstrated both on-line charge/discharge cycling and off-line static electrolyte stability study of at 2.0M vanadium concentration at -5 and 50⁰C. The new additive-assisted vanadium electrolyte provides a revolutionary solution to boost the VRB’s performance, stability, and cost to a whole new level.