A simple spray drying-assisted solid-state synthesis of LiFe0.67Mn0.33PO4/C cathode material for lithium-ion batteries

Abstract

A simple and scalable synthesis route for LiFe_0.67Mn_0.33PO₄/C cathode material using spray drying combined with high-temperature solid phase technology was developed. With Li₃PO₄ as the lithium source and cost-effective Mn₃O₄ replacing part of the iron, this process is compatible with the industrial production line of LiFePO₄. X-ray diffraction (XRD) confirmed that the synthesized material exhibited a single-phase olivine structure with a space group of Pnma. Scanning electron microscopy (SEM) revealed a spherical morphology. The synthesized material exhibits excellent rate and cycling performance under the low-grain micro-strain and conductive carbon network structure. Electrochemical testing demonstrated initial discharge capacities of 164, 163, 160, 157, 150, and 128 mAh g⁻¹ at rates of 0.1, 0.2, 0.5, 1, 2, and 5 C, respectively. Moreover, 96.16% of the capacity is retained after 200 cycles at 1C. This approach offers a viable pathway for the preparation of LiFe_1-xMn_xPO₄/C positive electrode materials with high energy density and high rate performance.