Energy conversion technologies towards self-powered electrochemical energy storage systems: the state of the art and perspectives

Energy conversion and storage are considered two of the most important technologies in today's green and sustainable energy science. Conjugating energy harvest and storage to fabricate self-powered electrochemical energy storage systems (SEESs) that harvest their operating energy from the environment holds great promise to power future portable and wearable electronics. SEESs represent a new trend in energy technologies. This review paper provides an overview of recent advances in SEESs powered by different energy conversion technologies with an emphasis on state-of-art organic solar cells, nanogenerators, and hybrid cells. Future challenges and perspectives of SEESs are also discussed.