Advanced aqueous rechargeable lithium battery using nanoparticulate LiTi2(PO4)3/C as a superior anode

Abstract

Poor cycling performance arising from the instability of anode is still a main challenge for aqueous rechargeable lithium batteries (ARLB). In the present work, a high performance LiTi2(PO4)3/C composite has been achieved by a novel and facile preparation method associated with an in-situ carbon coating approach. The LiTi2(PO4)3/C nanoparticles show high purity and the carbon layer is very uniform. When used as an anode material, the ARLB of LiTi2(PO4)3/C//LiMn 2 O 4 delivered superior cycling stability with a capacity retention of 90% after 300 cycles at 30 mA g-1 and 84% at 150 mA g-1 over 1300 cycles. It also demonstrated excellent rate capability with reversible discharge capacities of 115 and 89 mAh g-1 (based on the mass of anode) at 15 and 1500 mA g-1, respectively. The superior electrochemical properties should be mainly ascribed to the high performance of LiTi2(PO4)3/C anode, benefiting from its nanostructure, high-quality carbon coating, appropriate crystal structure and excellent electrode surface stability as verified by Raman spectra, electrochemical impedance spectroscopy (EIS), X-ray diffraction (XRD) and scanning electron microscopy (SEM) measurements.