Could Energy-efficient Bacteria Batteries Replace Lithium?

Lithium Ion Battery

Laptops and bacteria have a long and sickening history together. The next chapter, though, might turn the tide on the story.

As a new source of renewable energy, bacteria-powered batteries might become the next sick trend. (And we mean sick like cool, not germy.) The trickiest part will be finding a way to store the bacteria’s energy, as storage of solar, wind, and other forms of renewable energy can prove touchy.

That’s where bacteria batteries could help. They’d replace lithium batteries, which need checks in place for voltage and current surges. Lithium batteries age, even when not in use. Anyone who’s used one knows how hot they can get to the touch when they’re in use. And they cost more than other types, such as nickel batteries.

Researchers in The Netherlands have managed to merge two microbial energy systems into a bacteria battery. Their prototype could address these issues and present an efficient alternative to existing battery options.

Researchers put bacteria through a battery of tests

Bacteria may be tiny microorganisms, but when they work together, they have the potential to make an impact on a grand scale.

Sam D. Molenaar led the Dutch study at Wageningen University. His group merged microbial energy systems that:

1. Formed acetate from energy

Bacteria aids in transforming electrons into acetate by means of microbial electrical synthesis (MES). Acetate, a metal salt, stores electricity.

2. Transformed that acetate back into energy

A microbial fuel cell uses bacteria to process the acetate by oxidation. The process, called reduction/oxidation, releases electrons that can be used as energy.

The test

Fifteen times in 15 days, researchers charged the bacteria battery. It provided power for 16 hours in a small-scale trial. Then they discharged it for eight hours. Why? Solar energy production follows a similar day-night charge-discharge pattern.

Favorable results given these parameters have implications for these batteries to someday store solar power, too. With work, the bacteria battery could replace conventional technologies. With bacteria’s help, your laptop battery could store and convert renewable energy.

What it means

It’s tough to store power — especially renewable energy.

What if it wasn’t? American energy-storage company Tesla developed Powerwall. It’s a household battery that can store enough energy to power a home. The cost quickly becomes prohibitive, though – a single unit costs $3,000 USD.

Roadblocks remain to the popularization of the bacteria battery. Cycle efficiency, the measure of how much battery capacity remains after repeated recharges, reaches at least 80% in modern batteries. The Wageningen study reports a spike of 40% cycle efficiency. Also, living organisms power the bacteria battery, which won’t work if the microorganisms die.

Still, early results are favorable.

Studies show the average laptop keyboard harbors 7,500 bacteria. If the laptop battery could put a small fraction of that bacteria to work, a user could at least look up ways to keep a keyboard cleaner.