Photoinduced\nRechargeable Lithium-Ion Battery

Abstract

Lithium-ion battery (LIB) design\nis the predominant technology\nto power portable and mobile electric devices/equipment. Fast charging\nand self-powering of LIBs are significant but challenging features\nto be addressed for meeting the fast-paced society and emerging demands.\nHerein, we report a rational photorechargeable lithium-ion battery\n(photo-LIB) design using LiV₂O₅ as a photocathode\nby directly modifying a commercial LIB without using any additives,\nwhich works in both photoassisted fast charging and photo-only charging\nmodes. The photo-LIB attains a high specific capacity of 185 mAh g^–1 in as fast as 5 min under illumination, an enhancement\nof 270% referring to that in dark. Under the photo-only charging mode,\nthe device achieves a highest full-spectrum photo-energy conversion\nefficiency of 9% so far, demonstrating a highly efficient self-powering\nmode. We reveal that the improved performance of photo-LIB is due\nto reversible vanadium intervalence charge transfer and Li⁺ insertion/deinsertion in LiV₂O₅ under illumination.