US researchers develop water-based battery that can store solar and wind energy

Water-based batteries could underpin future sustainable power systems, claim researchers

Scientists in the US claim to have developed a water-based battery capable of storing solar and wind energy.

The researchers from Stanford University said that water-based batteries could become an efficient and affordable way to store power generated by wind and solar.

Their prototype is a three-inch manganese-hydrogen battery that currently stores just 20 milliwatt-hours of electricity. That would only power an LED flashlight.

However, the researchers are "confident" that they can create an industrial-grade system 10,000 times more powerful.

What we've done is thrown a special salt into water, dropped in an electrode, and created a reversible chemical reaction that stores electrons in the form of hydrogen gas

Yi Cui, a professor of materials science at Stanford, claims that manganese-hydrogen battery technology could one day be used in nationwide energy projects.

"What we've done is thrown a special salt into water, dropped in an electrode, and created a reversible chemical reaction that stores electrons in the form of hydrogen gas," Cui said.

Under the supervision of Wei Chen, the research team generated a reversible electron-exchange between water and manganese sulfate. The latter is used in dry cell batteries, fertilisers and paper products.

Then, by attaching the prototype to a power source, the researchers were able to mimic how a solar or wind source would power the battery.

We believe this prototype technology will be able to meet Department of Energy (DOE) goals for utility-scale electrical storage

As a result, the electrons created by the power source reacted with the manganese sulfate, which led to the creation of hydrogen-based energy.

Cui said the battery could power a 100-watt light bulb for twelve hours. "We believe this prototype technology will be able to meet Department of Energy (DOE) goals for utility-scale electrical storage," said the researcher.

He said the main benefit of the technology would be its affordability in terms of manufacturing and maintenance.

"Other rechargeable battery technologies are easily more than five times that cost over their life time," added Cui.

Former Department of Energy Secretary Steven Chu, who is now a professor at Stanford, said such technology should be adopted by the government to curb carbon emissions.

"While the precise materials and design still need development, this prototype demonstrates the type of science and engineering that suggest new ways to achieve low-cost, long-lasting utility-scale batteries," said Chu.