Researchers at Clemson University say they have made progress in improving the performance of aluminium-ion batteries.
Though aluminium-ion batteries are less toxic and more efficient than lithium-ion batteries, past attempts at making workable prototypes of an aluminium-ion battery have failed to produce a model that performs as well as a similar lithium-ion battery. Thus, consumers are still stuck with lithium-ion batteries, which use a relatively rare (and therefore expensive) substance as its element.
“In any given battery, something is either very rare or it’s toxic or it’s expensive. Those are the things that have been plaguing the battery industry,” explained R. A. Bowen Professor of Physics at Clemson University and director of the Clemson Nanomaterials Institute Apparao Rao.
In theory, aluminium should outperform lithium in a battery, as the ion used contributes three times the electrons. However, no battery has been developed to fully utilize that potential. According to the research team, improvements to the cathode and electrode
Anthony Childress, a graduate student at the Clemson Nanomaterials Institute and the first author of the Nano Energy paper, says that more research is key.
“The problem isn’t that aluminum ions are deficient. It’s that unlike lithium ions that have been around for a while, we do not know much about how aluminum ions behave inside the battery.”
The Clemson researchers determined that using thin sheets of aluminium foil and thin sheets of a substance called “few-layer graphene” would vastly improve the quality of the aluminium-ion battery.
“We knew that aluminum ions could be stored inside few-layer graphene,” explained Ramakrishna Podila, assistant professor of physics and astronomy. “But the ions need to be packed efficiently to increase the battery capacity. The arrangement of aluminum ions inside graphene is critical for better battery performance.”
“These aluminum batteries can last more than 10,000 cycles without any performance loss,” he continued. “Our hope is to make aluminum batteries with higher energy to ultimately displace lithium-ion technology.”
Rao estimates that the next area for research is finding cost-effective ways to manufacture the electrolytes, which are prohibitively expensive at present.
“This is a new battery with a new and better chemistry, which needs to be fine-tuned for commercial application,” he said. “We need to make it scalable enough so its cost comes down.”