Researchers Develop a ‘Coat of Armor’ to Keep Kids Safe from Ingesting Batteries

In 2013, more than 3,000 reported cases of accidental battery ingestion were reported, and the majority of these cases were in children under the age of 6. As you can imagine, what happens after a child swallows a battery is pretty scary.

“Ingested disc batteries require emergent removal from the esophagus,” says Giovanni Traverso, a gastroenterologist at Massachusetts General Hospital and a researcher at MIT. “The swallowing of these batteries is a gastrointestinal emergency given that tissue damage starts as soon as the battery is in contact with the tissue, generating an electric current and leading to a chemical burn.”

That’s why a team of researchers at Brigham and Women’s Hospital (BWH) have developed a simple “coat of armor” that encases small batteries and “renders them harmless” if swallowed. Their work was published online in the Proceedings of the National Academy of Sciences. The “coat of armor” offers a simple and inexpensive fix to what can be a deadly problem. 

“To date, there has been no innovation to address this issue with small batteries,” says Jeff Karp, a researcher in the Division of Biomedical Engineering at Harvard Medical School. “To address this challenge we sought to develop something that would render the battery inert, specifically when it was outside of a device.”

Here’s how it works:

The scientists discovered this unique substance in an unlikely place — touch screens. Using an off-the-shelf material known as a quantum tunneling composite, they identified a nanoparticle-based coating that, when subjected to pressure, allows an electrical current to pass through. In contrast, it allows no current to run in the absence of such pressure.

They used this material to coat one side of the batteries — covering the “minus” ends or the anodes. To determine the coating’s effectiveness, they teamed up with Traverso, exposing coated and uncoated batteries to gut tissue both in a laboratory dish and in living animals. In all cases, the coated batteries caused no damage while the uncoated batteries, as expected, caused significant damage.

“We set out to create a specialized coating that could switch from an insulator to a conductor when subjected to pressure,” said study c0-author Robert Langer, Institute Professor from the Harvard-MIT Division of Health Sciences and Technology.

Now, the team is looking into working with battery manufacturers to get the coated batteries into the hands of consumers.