Lithium ion batteries, the likes of which are found in modern day smartphones, can gain extended capacity with hydrogen-treated graphene, according to scientists at Lawrence Livermore National Laboratory in California.
A research team created electrodes by treating graphene nanofoam electrodes with hydrogen, replacing traditional electrode materials such as graphite.
They found that lithium ion batteries using the new electrodes had a higher capacity and charged faster.
Commercial applications of graphene materials for energy storage devices, including lithium ion batteries and supercapacitors, are currently constrained due to issues with producing the materials in large quantities at a low cost.
At present, the methods used leave behind significant amounts of atomic hydrogen which impacts the electrochemical performance of graphene due to defects in the material.
However, the Livermore scientists found that treating defect-rich graphene with low-temperature hydrogen actually improves the capacity of electrodes because it opens small gaps in the material that facilitate easier lithium penetration and energy transport.
"The performance improvement we've seen in the electrodes is a breakthrough that has real world applications," said Jianchao Ye, leading author on a paper which outlines the research.
Brandon Wood, another scientist working on the project, said: "We found a drastically improved rate capacity in graphene nanofoam electrodes after hydrogen treatment.
“By combining the experimental results with detailed simulations, we were able to trace the improvements to subtle interactions between defects and dissociated hydrogen.
“This results in some small changes to the graphene chemistry and morphology that turn out to have a surprisingly huge effect on performance."
Increasing the energy density of lithium ion batteries at a relatively low cost could have far reaching implications for other sectors such as renewable energy and electric vehicles.
In September, Canadian researchers demonstrated the first superconducting graphene which used a lithium atom coating.