Can Crabs Save the World?

I doubt it, but, hey, maybe this will work, Maryland’s Blue Crabs May Power Sustainable Future

A new paper by the University of Maryland’s Professor Liangbing Hu details the successful use of Blue Crab shells in batteries as an alternative to lithium. Specifically, chitin, a chemical that toughens exoskeletons in shellfish and insects, also has properties that promote superior recharging and better recyclability.

According to Seafood Source, the seafood industries leading publication,

“Vast quantities of batteries are being produced and consumed, raising the possibility of environmental problems,” Hu said. “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.”

Exploiting this widely consumed staple potentially offers a major tool in fighting climate change. This point is furthered if chitin can be harvested or produced sustainably. In contrast, lithium, by its very nature, will never be able to be produced sustainably. Like other metals, it must be mined, which carries an entire slew of negative environmental impacts. This is best illustrated by the New York Times in May 2021,

“Blowing up a mountain isn’t green, no matter how much marketing spin people put on it,”…

On the other hand, lithium is a trace element in seawater, with concentration of about 0.2 parts per million. Can that be concentrated economically? Maybe. 

If Maryland is to exploit this abundant resource well into the future, officials must work to stabilize the Blue Crab’s diminishing population. Long-time readers of Conduit Street will remember that populations of the iconic crustacean have been declining in the Chesapeake Bay since the 1990s.

Read the full story.

Read the full research paper.

OK, I actually did my homework, and read the abstract of the paper. Chitosan from crab shells is used in conjunction with zinc (a fairly common and cheap metal, and not terribly toxic) in the electrolyte of zinc acid batteries (think your old style A, B and C cells) to make them rechargeable.

I doubt that Maryland crab could provide enough chitosan for the industry if this technology really took off, but there are plenty of other commercial crabs, and crustaceans besides crabs (shrimp, lobsters, krill) are also potential sources of chitosan.

The Wombat has Rule 5 Sunday: Mrs. Santa out on time and under budget.