High power Na-ion capacitor with TiS2 as insertion host

Abstract

High power capability of the hybrid charge storage device Na-ion capacitor (NIC) is fabricated using battery type TiS2 as an insertion host with the double layer forming activated carbon (AC) as supercapacitor component. Earlier, it is presumed that Na/TiS2 system is considered as impractical energy storage system. TiS2 single crystals are synthesized and exhibit the reversible insertion of ~0.62 mol. Na. AC/TiS2 assembly is delivering the maximum energy density of ~38 Wh kg−1. One of the important aspects of this NIC is high power capability, which outperformed its analogue Li-ion capacitor fabricated under similar circumstances.