Reenergizing Renewable Solar and Wind Energy: New Battery Could Power Electrical Grid

There's a new way to reenergize the solar and wind energy industry. Researchers have created a low-cost, long-life battery that could enable renewable forms of energy to become major suppliers to the electrical grid.

There are currently several problems with wind and solar energy that researchers haven't quite figured out how to fix. When large and sudden power fluctuations occur due to changing weather conditions, for example, the electrical grid can't handle it. The electrical grid and energy solar systems must be able to smooth out the peaks and valleys of this intermittent power by storing excess energy and then discharging when input drops. The obvious solution to such a problem is creating the proper battery that can handle storing a vast quantity of energy and then supplying it later.

The most promising of these batteries happen to be "flow" batteries. These sources of power pump two different liquids through an interaction chamber where dissolved molecules undergo chemical reactions that store or give up energy. The chamber itself contains a membrane that allows ions not involved in reactions to pass between the liquids while keeping the active ions physically separated. Unfortunately, this design has its flaws.

First of all, the liquids within the battery are expensive. They contain rare metals such as vanadium, and making batteries that are large enough for grid storage would be extremely costly. In addition, the membrane within these batteries is also expensive and require frequent maintenance.

The new battery, which was designed by researchers from the U.S. Department of Energy's SLAC National Accelerator Laboratory and Stanford University, may solve these issues. The design uses only one stream of molecules that mostly consist of the relatively inexpensive elements lithium and sulfur. These molecules interact with a piece of lithium metal coated with a barrier that permits electrons to pass without degrading the metal. When discharging, the molecules absorb lithium ions; when charging, they lose them back into the liquid.

"In initial lab tests, the new battery also retained excellent energy-storage performance through more than 2,000 charges and discharges, equivalent to more than 5.5 years of daily cycles," said Yi Cui, one of the researchers, in a news release.

The battery could mean that there may finally be a way to effectively capture and store wind and solar energy for future use. That said, this battery still needs to be scaled up; until then, renewable energy will continue to be beset by the same problems.

The details of the new battery were published in the journal Energy & Environmental Science.

Want to see the battery? Check out the video below, courtesty of the SLAC National Accelerator Laboratory.