According to the October 3, 2014 issue of the journal Nature Communications, researchers at Ohio State University have combined the battery and solar cell to create the world’s first solar battery. The device is able to capture light like a solar panel, then store that energy in a cheap battery.
Yiying Wu, professor of chemistry and biochemistry, and his students says their patent-pending device would reduce cost by 25 percent. Additionally, the battery could be much more efficient than current solar energy. Typically, only 80 percent of electrons successfully make the trip from the solar cell to an external battery.. The new design converts light into electrons inside the battery, so almost 100 percent of electrons could be saved.
The design for the world’s first solar battery was inspired by an air-powered battery previously developed by Wu and doctoral student Xiaodi Ren. This battery won the $100,000 clean energy prize from the U.S. Department of Energy in 2014. To describe the way it works best, the battery breathes in when discharging and breathes out when charging. Researchers wanted to mimic this motion in the solar battery, but the solid semiconductors usually used in solar cells didn’t allow air to pass through.
Doctoral student Mingzhe Yu came up with a mesh solar panel made of titanium gauze. He grew titanium rods on this fabric, so air was able to pass through the mesh while the the rods capture sunlight. Additionally, this new design was able to incorporate the use of three electrodes, while connecting a solar cell to a battery usually requires four.
How Does it Work?
When charging, light hits the solar mesh panel and creates electrons. These electrons aid in the decomposition of lithium peroxide into lithium ions and oxygen. The oxygen is released and the lithium ions are stored in the battery as lithium metal. During discharge, the battery consumes the oxygen from the air in order to reform the lithium peroxide. An ion additive in the electrolyte carries electrons between the battery electrode and the mesh solar panel.
For more information on the world’s first solar battery, you can check out this press release by Ohio State University.