Solar-powered electrochemical energy storage: an alternative to solar fuels

Because of the intermittent nature of solar radiation, being able to simultaneously convert and store solar energy is a significant advance for efficiently harnessing solar energy. Solar fuels have already been recognized as a promising method towards this goal and have attracted tremendous research interest recently. Alternatively, this goal can also be achieved by using the solar-powered electrochemical energy storage (SPEES) strategy, which integrates a photoelectrochemical cell and an electrochemical cell into a single device. The integrated device is able to harvest solar energy and store it in situ within the device via a photocharging process and also distribute the energy as electric power when needed. This essay reviews the past SPEES research and analyzes its future prospects with a special emphasis on chemical design and material choices. We hope that the article will help draw more research attention to this field and stimulate additional exciting investigations toward more efficient solar energy utilization.