Oxalic acid-assisted preparation of LTO-carbon composite anode material for lithium-ion batteries

Abstract

This study presents an oxalic acid-assisted method for synthesizing spinel-structured lithium titanate (Li4Ti5O12; LTO)/carbon composite materials. The Ag-doped LTO nanoparticles (NPs) are synthesized via flame spray pyrolysis (FSP). The synthesized material is used as a precursor for synthesizing the LTO-NP/C composite material with chitosan as a carbon source and oxalic acid as an additive. Oxalic acid improves the dissolution of chitosan in water as well as changes the composition and physical and chemical properties of the synthesized LTO-NP/C composite material. The oxalic acid/chitosan ratio can be optimized to improve the electrochemical performance of the LTO-NP/C composite material, and the electrode synthesized with a high mass loading ratio (5.44 mg cm−2) exhibits specific discharge capacities of 156.5 and 136 mAh g−1 at 0.05 C- and 10 C-rate currents, respectively. Moreover, the synthesized composite LTO-NP/C composite material exhibits good cycling stability, and only 1.7% decrease in its specific capacity was observed after 200 charging–discharging cycles at 10 C-rate discharging current.