High energy density hybrid lithium-ion capacitor enabled by Co3ZnC@N-doped carbon nanopolyhedra anode and microporous carbon cathode

Abstract Hybrid lithium-ion capacitors (HLICs) have drawn great attention as promising energy devices, because they can integrate the high energy density of lithium ion batteries and the high power density of supercapacitors, and their low cost and long cycling-life are well suited to large-scale energy storage. However, the development of HLICs is usually limited by the kinetics mismatch between the battery-type anode and capacitor-type cathode. In this study, hierarchical Co3ZnC nanoparticle encapsulated mesoporous nitrogen-doped carbon nanopolyhedra (Co3ZnC@NC) synthesized by one-step pyrolysis of bimetallic-organic-frameworks are used as anode material for HLICs, exhibit high lithium storage capacity and excellent rate performance. Moreover, heteroatom-doped microporous carbon (MPC) derived from nature-abundant biomass (pine needles) are employed as cathode material, demonstrating good rate capability and long cycle stability. As a result, the as-prepared Co3ZnC@NC||MPC HLICs deliver high energy densities (up to 141.4 Wh kg−1), high power densities (up to 10.3 kW kg−1) and long cycle life within the wide operating voltage range (1.0–4.5 V). These encouraging results of the HLICs bridge the gap between supercapacitors and batteries, and show great potential in next-generation energy storage devices.