Recent progress of graphene-based materials in lithium-ion capacitors

Lithium-ion capacitor (LIC) is generally composed of a battery-type anode and a capacitor cathode, which is considered as a promising alternative to bridge the energy/power gap between lithium-ion batteries and supercapacitors and achieve both fast energy harvesting and long-term stability. Numerous efforts have been devoted to the search for suitable high-capacity cathode materials and high-rate anode materials. In this context, graphene has attracted unprecedented interest due to such peculiar features as high surface, high electric conductivity, and high chemical stability, offering great prospect in LICs with improved electrochemical performance. Herein, we provide a critical overview of the latest progress related to graphene and graphene-based materials in this booming field. A brief summary of the state-of-art electrode materials in LICs is introduced, which is followed by a systematic review of graphene-based materials as cathode and anode materials in LICs. In the end, a perspective is tentatively presented to highlight major challenges for future applications of graphene materials in LICs.