Storing clean energy typically means using batteries that are bad for the environment but thanks to a new zinc option put together with biodegradable material made from crab shells that could be about to change.
In a paper published last month in the journal, Matter, scientists showed that the parts of a battery that take thousands of years to degrade can be replaced with climate-friendly alternatives.
“Vast quantities of batteries are being produced and consumed, raising the possibility of environmental problems,” explains lead author Liangbing Hu, director of the University of Maryland’s Center for Materials Innovation. “For example, polypropylene and polycarbonate separators, which are widely used in Lithium-ion batteries, take hundreds or thousands of years to degrade and add to environmental burden.”
With this new battery the electrolyte element is made from a biological material called chitosan, which can be sourced from crab shells and other crustaceans, and more than 60% of the battery is broken down by microbes. The zinc left over, used in place of lead or lithium, can also be recycled.
“Chitosan is a derivative product of chitin. Chitin has a lot of sources, including the cell walls of fungi, the exoskeletons of crustaceans, and squid pens,” says Hu. “The most abundant source of chitosan is the exoskeletons of crustaceans, including crabs, shrimps and lobsters, which can be easily obtained from seafood waste. You can find it on your table.”
Hu and his team are continuing their research with the goal of making further improvements that will also factor in the impact of the manufacturing stage.
“In the future, I hope all components in batteries are biodegradable,” adds Hu. “Not only the material itself but also the fabrication process of biomaterials.”