Improvement and analysis of the hydrogen-cerium redox flow cell

The H₂-Ce redox flow cell is optimized using commercially-available cell materials. Cell performance is found to be sensitive to the upper charge cutoff voltage, membrane boiling pretreatment, methanesulfonic-acid concentration, (+) electrode surface area and flow pattern, and operating temperature. Performance is relatively insensitive to membrane thickness, Cerium concentration, and all features of the (−) electrode including hydrogen flow. Cell performance appears to be limited by mass transport and kinetics in the cerium (+) electrode. Maximum discharge power of 895 mW cm⁻² was observed at 60 °C; an energy efficiency of 90% was achieved at 50 °C. The H₂-Ce cell is promising for energy storage assuming one can optimize Ce reaction kinetics and electrolyte.