Superior Anodic Lithium Storage Behavior of Organic Pigment 2,9-Dimethylquinacridone

Abstract Organic anode materials are of great importance for the development of lithium ion batteries (LIBs) with less reliance on inorganic minerals. In this work, it is found that 2,9-dimethylquinacridone (2,9-DMQA), an organic pigment, can have excellent electrochemical performances when serving as the anode material in LIBs. 2,9-DMQA based LIB anode manifests a high specific capacity of 1150 mAh g-1 at 0.1 A g-1. Even at a high current density of 5.0 A g-1, the capacity of 2,9-DMQA can still be retained at ∼385 mAh g-1, outperforming many recently reported LIB anodes. The results from experiments and calculation suggest that 2,9-DMQA can reversibly associate with ∼ 22 Li+, corresponding to a theoretical capacity of 1732 mAh g-1. Additionally, the full-cell with 2,9-DMQA as anode and LiCoO2 as cathode can deliver the energy and power density of 325.8 Wh kg-1 and 1137.1 W kg-1, respectively, which are better than most of recently reported full-cells, implying the intriguing potential of the 2,9-DMQA anode in organic LIBs.