Integrated solar flow battery

A device combining a solar cell and a battery can store solar energy for future use. Credit: David Tenenbaum/UW-Madison

Renewable energy

Record-breaking battery saves sunshine for a rainy day

Device combines solar-cell and battery technology to store energy from the Sun with unprecedented efficiency.

Solar cells can be integrated with batteries to create a single device that efficiently captures, stores and releases solar energy — even when the Sun isn’t shining.

Song Jin at the University of Wisconsin–Madison and his colleagues paired a highly efficient photovoltaic cell with a high-voltage battery. The solar energy harvested by the cell is directly captured by the battery, which uses liquid electrolytes to store energy in chemical form.

This solar-flow battery converts, stores and releases the solar energy in the form of electricity, achieving a record efficiency of 14.1%. The researchers suggest that further improvements to the battery are possible, which could open the door for the utilization and storage of solar energy at sites that are not connected to the electrical grid.