Recent trends in supercapacitor-battery hybrid energy storage devices based on carbon materials

Currently, tremendous efforts have been made to obtain a single efficient energy storage device with both high energy and power density, bridging the gap between supercapacitors and batteries where the challenges are on combination of various types of materials in the devices. Supercapacitor-battery hybrid (SBH) energy storage devices, having excellent electrochemical properties, safety, economically viability, and environmental soundness, have been a research hotspot in the current world of science and technology. Carbon derivatives from 0D to 3D, e.g., activated carbon, graphene, porous carbon etc., are employed as one of the promising electrode materials due to abundance in reserve, economical viability, adjustable pore size, and wide range of operation potential. Hybrid supercapacitor applications are on the rise in the energy storage, transportation, industrial, and power sectors, particularly in the field of hybrid energy vehicles. In view of this, the detailed progress and status of electrochemical supercapacitors and batteries with reference to hybrid energy systems is critically reviewed in this paper. The focus is also given to the recent trends in porous and graphene-based carbon electrode materials in asymmetric capacitor and metal ion capacitors (e.g. Li-ion, Na-ion, and K-ion capacitors) and its electrochemical properties for its potential applications. The output of this unique review will serve as a database for extending the R&D in the field of supercapacitor-battery hybrid system for possible applications including e-vehicles.