SBIR-STTR Award

In this project we aim to develop a novel iron-titanium redox flow battery with two detachable electrolyte storage tanks. Iron-titanium batteries cost $80/kWh for energy storage-lower than$369/kWh of lithium-ion batteries and $399/kWh of vanadium flow batteries. An iron-titanium battery employs no self-igniting materials and its electrolytes are comprised of ~60% water- deeming it fire safe. As a result iron-titanium batteries could be ideal devices for fire-safe low- cost and long-duration (>10 h) storage of clean energy generated in rural areas. This proposal also wants to explore the possibility of using freights and pipelines for transporting clean electricity from country sides to end-users in metropolises. A flow battery separates electrolyte reservoirs from two electrodes. When it is charged electricity is converted to chemical energy which is stored in iron (II) and titanium (IV) salts that are dissolved in two aqueous solutions respectively. Such water-based electrolytes can be transported from a rural area via for example trucks trains boats or pipelines to another battery cell in a different location where charged electrolytes will be pumped through the electrode compartments of the second cell-converting chemical energy back to electricity. The spent electrolytes comprised of iron (III) and titanium (III) will be brought back to the original cell in the rural area for recharging. If it works this strategy could solve the transmission and distribution problem of renewable energy- potentially transforming rural areas into the energy production centers of the U.S. and enabling the export of clean energy to the larger global market. A detachable battery can also power an agriculture vehicle for its continuous operation in fields. The recharge of the battery will be achieved by simply exchanging electrolyte storage tanks. The major goals of this project include: (1) increasing the energy density of charged electrolytes by varying the composition of iron and titanium water solutions respectively for reducing electrolyte transportation costs; and (2) optimizing the cell structure for improved battery performance.