β-Cyclodextrin coated lithium vanadium phosphate as novel cathode material for lithium ion batteries

Abstract

As a new carbon source, β-cyclodextrin was used to synthesize a Li₃V₂(PO₄)₃/C cathode material for lithium ion batteries (LIBs) via a rheological phase method. X-ray diffraction (XRD) patterns demonstrated that the sample had a pure monoclinic structure and sharp diffraction peaks, indicating good crystallinity. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images showed that the sample had a uniform and optimal particle size, which is beneficial to the electrochemical performance of LIBs. In the voltage range of 3.0–4.3 V, the initial discharge capacity of the sample was 111 mA h g⁻¹ and remained 109.3 mA h g⁻¹ after 50 cycles at 0.1C rate. In the high voltage range of 3.0–4.8 V, the initial discharge capacity was 151.4 mA h g⁻¹ and remained 131.5 mA h g⁻¹ after 25 cycles at 0.1C rate, indicating that β-cyclodextrin is a promising carbon source for LIB materials.