Chemical energy

Germs power new paper batteries

paper battery
paper battery

Engineers in upstate New York have invented a folded paper device that looks like a decorated art project. But don’t be fooled. This is actually a paper-based battery. No, it doesn’t look like any of those metal batteries running flashlights or smartphones. This alternative to electronics is based on paper. It represents a step forward in the field of papertronics (short for paper electronics). In these systems, the battery can be printed on a page. Well, most of it can: The battery’s power consists of living bacteria.

Paper electronics are simple to make and inexpensive, notes study leader Seokheun Choi. He’s an enginee at Binghamton University, part of the State University of New York system. These batteries also would be flexible and disposable, he adds. And powered by germs, they need no electrical outlet to recharge. They just need more bacteria, which can be found everywhere — including in dirty water.

Most batteries use chemicals to generate electricity. Substituting bacteria can be an advantage, Choi says. “They are cheap, self-repairing and self-maintained,” he notes. What paper-based batteries won’t do is generate much power. They do, however, create enough to run small devices in faraway or dangerous places — such as a battlefield. They might also find use in medicine. For instance, they might power tiny sensors, such as the types used to measure blood sugar.

Choi and Yang Gao, also at Binghamton, describe their new invention in the January 2017 issue of Advanced Materials Technology.

Such devices are based on an observation made more than a century ago — that microbes produce a trickle of electricity as they digest food. Scientists refer to the bio-batteries based on this principle as microbial fuel cells.

A fuel cell generates electricity like a regular battery. But a regular battery stops producing electricity when its internal…