A researcher at the University of California, Berkeley has developed a new technology that could extend the lifespan of hydrogen-producing fuel cells and lower their production costs. This advancement may help make hydrogen fuel more affordable and environmentally friendly.
Hydrogen is widely used in heavy transport, fertilizer production, chemical manufacturing, and as a method for storing energy on the electrical grid. Currently, most hydrogen is produced from fossil fuels such as natural gas and coal, which results in significant carbon dioxide emissions.
An alternative method uses electrolyzers to split water into hydrogen and oxygen using electricity. However, producing hydrogen this way is currently too expensive to compete with fossil-fuel-derived hydrogen unless subsidies are involved. Using renewable sources like wind and solar can reduce costs, but electrolyzers must also become cheaper to manufacture because they operate intermittently when renewable power is available.
Shannon Boettcher, a professor at UC Berkeley’s Department of Chemical and Biomolecular Engineering and Department of Chemistry, leads a team working on new electrolysis technology using ion-conducting polymers. Traditional designs have faced challenges due to rapid electrode degradation. The team has now redesigned these electrolyzers to better protect electrodes from damage.
“If you can make this really work, it’s not unreasonable to expect a 5x or 10x reduction in the cost of these membrane electrolyzers, which would truly enable us to put them on the grid as a variable-load offtake of low-cost electrons and deliver hydrogen,” said Boettcher.
Electrolyzers allow excess energy generated during peak periods for solar and wind power to be stored as hydrogen for later use in industry or for seasonal electricity storage.
“We’re trying to develop electrochemical technologies for making hydrogen that can take advantage of all that intermittent electricity,” Boettcher said.
The research findings were published on October 16 in the journal Science.
Boettcher explained that polymer electrode degradation happens when polymers lose electrons during operation. This oxidative process limits commercial competitiveness. The project received funding from the U.S. Department of Energy until its grant was terminated during a recent government shutdown; UC Berkeley is contesting this decision.
There are two main types of commercial electrolyzers: liquid alkaline systems that use caustic solutions similar to drain cleaners but are difficult to maintain at high rates or with intermittent operation; and proton exchange membrane (PEM) systems that use acidic membranes but require expensive materials like iridium and stable fluorocarbons.
Boettcher’s approach combines advantages from both types by developing an anion-exchange-membrane water electrolyzer using solid polymer membranes with alkaline electrolyte properties. He said this offers “all the low-cost material advantages of one technology — the alkaline technology — with all the advantages of the membrane technology, including lower cost, higher safety and less maintenance.”
To address degradation issues at the anode (where oxidation occurs), Boettcher’s team mixed zirconium oxide inorganic polymer with organic ion-conducting polymers. This forms a protective “passivation” layer around the anode electrode, reducing degradation rates by up to one hundred times.
“We get a hundred times decrease in the degradation rate,” he said. “We’re not all the way there (to a commercially viable electrolyzer), but this is by far the biggest knob we’ve found to get there.”
The new anode design involves depositing cobalt-based catalyst onto steel mesh before covering it with the polymer mix; then adding a cathode completes the system.
Boettcher continues research aimed at further improving performance as director of UC Berkeley’s Center for Electrochemical Science, Engineering and Technology (CESET). He also holds the Theodore Vermeulen Chair in Chemical Engineering at UC Berkeley.
He anticipates additional progress thanks to California’s $28 million investment announced in September aimed at accelerating commercialization of electrochemical technologies such as next-generation batteries through organizations like Hayward’s Electrochemistry Foundry. UC Berkeley is launching new courses related to batteries and electrochemistry via its Electrochemistry Academy while partnering with local innovation hubs for student internships.
“Hydrogen production, storage, shipping — they’re all expensive and there’s a lot of challenges. But the progress in this technology is incredible,” Boettcher said. “The era of hydrogen fuel from electrolysis outcompeting fossil fuels without subsidy for many different applications is coming.”
Funding came from U.S. Department of Energy grant DE-EE0011322. Coauthors include researchers from UC Berkeley, Lawrence Berkeley National Laboratory (Berkeley Lab), Versogen (a Delaware company working toward commercialization), University of Delaware, and Stanford University.
