Crab shells are key to sustainable batteries


College Park – University of Maryland researchers have developed a partially biodegradable battery for electric vehicles. It consists of zinc and chitosan, a material made from crab, lobster and shrimp shells. Chitosan can degrade within five months.

As electric vehicles become more common, carbon emissions are also expected to decline. But the lithium-ion batteries that power clean cars could become a major environmental problem in the future if they don’t become more sustainable.

Researchers at the University of Maryland have now figured out how to make batteries for electric vehicles from the shells of crabs, lobsters and shrimp. Publishing their findings in the journal Matter, the scientists report they made a zinc battery from biodegradable electrolytes in crustaceans.

“Batteries are produced and consumed in large quantities, which can lead to environmental problems,” Liangbing Hu, professor of materials science and engineering and lead author of the article in the university publication Maryland Today, is quoted as saying.

Hu explained that some chemicals in lithium-ion batteries could take hundreds or thousands of years to decompose. Moreover, flammable and corrosive substances are used in these batteries. The mussel-based battery, on the other hand, uses a biological gel called chitosan that degrades in about five months, leaving zinc behind instead of lead or lithium.

“The most abundant source of chitosan is the shells of crustaceans, which can be easily obtained from seafood waste,” Hu is quoted as saying. “It can be found on the dinner table. Zinc is more abundant in the earth’s crust than lithium. In general, well-developed zinc batteries are cheaper and safer.” .

According to Hu’s data, the energy efficiency of the battery he and colleagues developed is 99.7 percent after 1000 cycles. It is therefore a good option for storing energy from wind and solar sources, he said. Hu added that he would like to further develop his designs to include more biodegradable elements in electric vehicle batteries and the processes to make them. ce/jd