How do you store electricity in a way that is large and powerful enough to support the electric grid, as well as reliable, safe, environmentally sustainable, and inexpensive? One way may be to make a major component of the rechargeable battery mostly from water and the rest of the device primarily from abundant materials.

That is the vision of dozens of the best energy storage experts from 15 research institutions across the United States and Canada, led by Stanford University and SLAC National Accelerator Laboratory. After a competitive process, the U.S. Department of Energy today announced its support for this energy hub research project, called the Aqueous Battery Consortium. The project can receive up to $62.5 million over five years as part of the DOE’s Energy Innovation Hubs program. The other battery-centered Energy Innovation Hub announced today by the DOE is the Energy Storage Research Alliance, led by Argonne National Laboratory.

“This project will undertake the grand challenge of electrochemical energy storage in a world dependent on intermittent solar and wind power. We need affordable, grid-scale energy storage that will work dependably for a long time,” said the project’s director, Yi Cui, a Stanford professor of materials science and engineering, of energy science and engineering, and of photon science at SLAC.

A huge amount of stationary energy storage will be needed to reduce net global greenhouse gas emissions to zero, said Cui, and water is the only realistic solvent available at the quantity and cost needed for such batteries.

“How do we control charge transfer between solids and water from the molecular to the device scale and achieve reversibility with an efficiency of nearly 100 percent?” asked Cui. “We don’t know the solutions to those hard problems, but with the Department of Energy’s support we intend to find out.”

A New Aqueous Battery
The lead-acid batteries that start combustion engines in conventional vehicles are a type of aqueous battery that has been in wide use for decades. However, for their size, lead-acid car batteries do not hold much energy, even though they can briefly supply a surge of current to start your car.