Abstract: A stabilized vanadium electrolyte solution for use in an all-vanadium redox cell or battery, the stabilized electrolyte solution comprising vanadium redox ions, an electrolyte and a stabilizing agent, wherein precipitation of vanadium redox ions from the electrolyte solution is prevented or reduced by the stabilizing agent when precipitation of the vanadium redox ions would otherwise occur and wherein the stabilizing agent is present in the electrolyte solution at a concentration of from 0.05 to 20% mol/mol of stabilizing agent to vanadium redox ions.

Abstract: Disclosed is a method for preparing a high energy density (HED) electrolyte solution for use in an all-vanadium redox cells, a high energy density electrolyte solution, in particular an all-vanadium high energy density electrolyte solution, a redox cell, in particular an all-vanadium redox cell, comprising the high energy density electrolyte solution, a redox battery, in particular an all-vanadium redox battery, comprising the HED electrolyte solution, a process for recharging a discharged or partially discharged redox battery, in particular an all-vanadium redox battery, comprising the HED electrolyte solution, a process for the production of electricity from a charged redox battery, and in particular a charged all-vanadium redox battery, comprising the HED electrolyte, a redox battery/fuel cell and a process for the production of electricity from a redox battery/fuel cell.