Combination of Solar Cell and Battery – A Solar Flow Battery – Could Make Electricity More Accessible in Remote Areas

A recent paper published in the journal, Chem, highlights the successful combination of a solar cell and a battery to form a solar flow battery (SFB), designed to act as both a solar cell and a storage system. Researchers from the University of Wisconsin-Madison and King Abdullah University of Science and Technology (KAUST) have realized a 14.1 percent round-trip efficiency – the trip from solar collection to electricity output – and expect to see even better results in future.

The batteries have multiple modes: they can be charged with electricity, convert sunlight to electricity, and allow solar energy to be stored as chemical energy to deliver it later at night or in sunless conditions. The team believes these could make electricity more accessible in remote regions of the world.

“These integrated solar flow batteries will be especially suitable as distributed and stand-alone solar energy conversion and storage systems in remote locations and enable practical off-grid electrification,” Jin stated. “Compared with separated solar energy conversion and electrochemical energy storage devices, combining the functions of separated devices into a single, integrated device could be a more efficient, scalable, compact, and cost-effective approach to utilizing solar energy.”

The device, in its current configuration, is too expensive for commercial and mass production but Jin believes simpler designs, cheaper solar cell materials, and technological advances could help cut costs in the future.

“We believe we could eventually get to 25% efficiency using emerging solar materials and new electrochemistry,” says Jin. “At this efficiency range, without using the expensive solar cells, it should be quite competitive with other renewable energy technologies. Then I think commercialization could be possible.”