Automatic operation of decoupled water electrolysis based on bipolar electrode

作者：Zhao, Meng-Jie; He, Qian; Xiang, Ting; Ya, Hua-Qin; Luo, Hao; Wan, Shanhong; Ding, Jun^*; He, Jian-Bo^*

来源：RENEWABLE ENERGY, 2023, 203: 583-591.

DOI：10.1016/j.renene.2022.12.083

• Decoupled water electrolysis
• Bipolar electrode
• Gas crossover
• High purity hydrogen
• Automatic control

Electrolytic hydrogen production faces a technological issue of gas crossover through the ion-membrane between hydrogen and oxygen chambers, especially under renewable energy low power driving conditions. As a solution, decoupled water electrolysis was proposed and has made important progress in laboratory research but faces the problem of how to implement it in industry. The present work develops a decoupled alkaline water electrolysis system without the need to change the filter press structure of industrial electrolyzers. A wireless bipolar elec-trode was designed and prepared from a redox pair (NiOOH/Ni(OH)(2)), which functions as a substitute for conventional ion-membrane but enables complete blocking of the gas crossover (and ion transfer also) between the hydrogen and oxygen chambers. A matching control scheme was designed and implemented for continuous water electrolysis. The high purity hydrogen production achieved a coulombic efficiency of 99.2% and a specific electricity consumption of 57.5 kWh kg(-1) H-2 at a current density of 50 mA cm(-2). This bipolar decoupling scheme of automatic operation makes an important step towards industrial implementation of decoupled water elec-trolysis technology.