Lithium-ion capacitors (LICs) are combinations of LIBs and SCs which phenomenally improve the performance by bridging the gap between these two devices. In this review, we first introduce the concept of LICs, criteria for materials selection and recent trends in the anode and cathode materials development.
However, in the present state of the art, both devices are inadequate for many applications such as hybrid electric vehicles and so on. Lithium-ion capacitors (LICs) are combinations of LIBs and SCs which phenomenally improve the performance by bridging the gap between these two devices.
Energy storage mechanisms of LICs compared with LIBs and SCs (b). Recently, lithium-ion capacitors (LICs), typically consisting of LIB-typed cathode and SC-typed anode, is regarded as a promising candidate to bridge the gap between LIBs and SCs which can deliver both high energy and power densities [, , , ].
Lambert et al. compared SCs and LICs for power electronic applications through AC analysis. Lambert showed that the lithium ion capacitor is more suitable for power electronic device applications as it can tolerate a higher frequency than the other established technologies.
Anode materials like graphite, lithium titanate (LTO), hard carbon, tin/cobalt alloy, silicon/carbon have been used. Interestingly, LICs can be fabricated by borrowing anode from the LIB and cathode from the EDLC with lithium-ion salt solution in an organic electrolyte.
Conceptual presentation of fabrication with Li-ion capacitors. Li-ion battery (LIB) is a rechargeable energy storage device, where lithium ions are inserted and extracted into/from the negative electrode while charging and discharging (Fig. 2). The basic difference in the SC and LIB is their charge storage mechanism.