Distribution of electrolytes in a flow battery

A method of determining a distribution of electrolytes in a flow battery, the method comprising:

• (a) providing a flow battery with a fixed amount of fluid electrolyte having electrochemically active species, the electrochemically active species having multiple reversible oxidation states, a portion of the fluid electrolyte serving as an anolyte and a remainder of the fluid electrolyte serving as a catholyte;
• (b) determining an instant average oxidation state of the electrochemically active species in the anolyte and the catholyte;
• and
• (c) responsive to the determined instant average oxidation state, adjusting an instant molar ratio of the electrochemically active species between the anolyte and the catholyte to increase a relative energy discharge capacity of the flow battery for the determined instant average oxidation state, the relative energy discharge capacity being an instant energy discharge capacity based on the instant molar ratio relative to a maximum capacity based on a fully balanced molar ratio between the anolyte and the catholyte, and wherein the adjusting includes partially mixing the anolyte and the catholyte together into non-equal volumes of the anolyte and the catholyte in the flow battery.

A method of determining a distribution of electrolytes in a flow battery, the method comprising:

• (a) providing a flow battery with a fixed amount of fluid electrolyte having electrochemically active vanadium species, the electrochemically active vanadium species having multiple reversible oxidation states, a portion of the fluid electrolyte serving as an anolyte and a remainder of the fluid electrolyte serving as a catholyte;
• (b) determining an instant average oxidation state of the electrochemically active vanadium species in the anolyte and the catholyte;
• and
• (c) responsive to the determined instant average oxidation state, adjusting an instant molar ratio of the electrochemically active vanadium species between the anolyte and the catholyte to increase a relative energy discharge capacity of the flow battery for the determined instant average oxidation state, the relative energy discharge capacity being an instant energy discharge capacity based on the instant molar ratio relative to a maximum capacity based on a fully balanced molar ratio between the anolyte and the catholyte, and wherein the adjusting includes partially mixing the anolyte and the catholyte together into non-equal volumes of the anolyte and the catholyte in the flow battery.