Progress and prospects of lithium-ion capacitors: a review

With advancements in renewable energy and the swift expansion of the electric vehicle sector, lithium-ion capacitors (LICs) are recognized as energy storage devices that merge the high power density of supercapacitors with the high energy density of lithium-ion batteries, offering broad application potential across various fields. This paper initially presents an overview of the developmental history, energy storage mechanisms, and classifications of LICs. It then concentrates on the latest advancements in anode and cathode materials for LICs, systematically reviewing strategies for optimizing electrochemical performance through microstructure adjustment, elemental doping, and the use of composite materials. Furthermore, it delves into the recent progress in the electrolyte system of LICs and prelithiation technologies, examining the features of different electrolyte systems and detailing various prelithiation approaches along with their merits and drawbacks. In conclusion, this paper summarizes and anticipates the current research trends in LICs, offering new perspectives and directions for future investigations.