Redox Flow Cell for Renewable Hydrogen

The COVID-19 lockdown offers plenty of chances for us to think about ways to advance the use of green hydrogen in the marketplace. One such solution comes from Nel Hydrogen and PNNL.

The teams at Nel Hydrogen and also experts led by Wei Wang, the chief scientist for energy storage research at the Pacific Northwest National Laboratory in Washington, could prove essential to finding a novel solution, redox flow cells.

Joining forces in 2016, they’ve worked together and have received funding to help further study and knowledge of the subject. They have come up with the redox flow cell mentioned above; a unique hybrid of redox-flow batteries and a water electrolyzer. This is capable of taking the best of both worlds, combining them into a nifty system.

By working as both a battery and a generator, this flow cell would be able to handle the two sides of the problem – development and storage. This is reversible fuel cell, and would be made by using a positive and negative electrolyte which is stored in separate tank spots. These would then be pumped into the battery as needed, and the redox reaction created would be able to generate the electricity at the battery’s electrodes.

According to professor Wang, “We introduce iron as a middleman, so we can separate electrolysis into two reactions. The system gives you flexibility… you could do the regeneration during evening time when electricity prices are at a peak … And because the hydrogen-iron cell uses about half the voltage of a traditional electrolyzer, you can generate hydrogen at a much cheaper cost if you do everything right.”

This is a unique and intelligent step forward in what has been a very hard industry to crack. Known as the ‘middleman’ to some who have worked on the project, this could help to become the long-term solution to making hydrogen usage a realistic property moving forward.

Citation

https://spectrum.ieee.org/energywise/energy/renewables/storing-renewable-energy-hydrogen-redoxflow-cell