A basket of Maryland blue crabs could hold the secret for sustainable battery production. New Maryland Engineering-led research uses chitosan from crab shells to create a biodegradable electrolyte for renewable energy storage. Photo by John T. Consoli
Electric vehicles are a major part of the equation for protecting Earth’s climate, but not everything adds up yet: The batteries powering these rolling sustainability solutions aren’t always sustainable themselves.
But now University of Maryland engineers have created a zinc battery with a biodegradable electrolyte from an unexpected source—crab shells. The discovery was presented in a paper this month in the journal Matter.
“Vast quantities of batteries are being produced and consumed, raising the possibility of environmental problems,” said the lead author and materials science and engineering Professor Liangbing Hu, director of UMD’s Center for Materials Innovation. The study’s other authors are affiliated with the University of Houston and UMD’s Department of Materials Science and Engineering.
For example, he said, polypropylene and polycarbonate separators, which are widely used in lithium-ion batteries, will take hundreds or thousands of years to degrade.
Current batteries use an often-flammable or corrosive electrolyte to shuttle ions back and forth between positively and negatively charged terminals within the battery, providing current. The new battery, which could be used to store renewable power from large-scale wind and solar sources, uses a gel electrolyte made from a biological material with many natural sources called chitosan.
“The most abundant source of chitosan is the exoskeletons of crustaceans, including crabs, shrimps, and lobsters, which can be easily obtained from seafood waste,” Hu said. “You can find it on your table.”
A biodegradable electrolyte means that about two-thirds of the battery could be broken down by microbes, with the chitosan electrolyte decomposed completely within five months. This leaves behind the metal component, in this case zinc, rather lead or lithium.
“Zinc is more abundant in earth’s crust than lithium,” said Hu. “Generally speaking, well-developed zinc batteries are cheaper and safer.”
This zinc and chitosan battery has an energy efficiency of 99.7% after 1,000 battery cycles, making it a viable option for storing energy generated by wind and solar for transfer to power grids, he said.
Hu said he and his team will continue working on making batteries that are even more environmentally friendly, including throughout the manufacturing process.
“In the future, I hope all components in batteries are biodegradable,” said Hu. “Not only the material itself but also the fabrication process of biomaterials.”
IN THE NEWS
- The Guardian, Crab and lobster shells could be used to make renewable batteries, Sept. 1
- Popular Science, Sustainable batteries could one day be made from crab shells, Sept. 1
- CNET, Batteries Made From Crab Shells Could Power Your Future Car, Sept. 1
- New Scientist, Battery made of crab shell and zinc is rechargeable and biodegradable, Sept. 1
- IFLScience, Batteries Made From Crabs And Lobsters Could Be The Future Of Renewable Energy, Sept. 2
- Vice, Your Electric Car Could Run On Crabs One Day, Sept. 2
- Newsweek, Scientists Say They've Created Sustainable Battery Out of Shellfish Casings, Sept. 2
- Gizmodo, Making Batteries Out of Crab Shells May Be a Great Idea, Sept. 2
- WTOP, From crab feast to EV: Sustainable batteries could be made from crab shells, Sept. 5
- [VIDEO] Fox 13 Seattle, The power of crabs: Shells used as batteries, Sept. 6
- Popular Mechanics, Crabs Could Be the Unlikely Hero the Battery Industry Needs, Sept. 8
This article, which originally appeared in Maryland Today, is based on a press release from Cell Press.
September 7, 2022