Excellent electrochemical performance of LiFe0.4Mn0.6PO4 microspheres produced using a double carbon coating process

Abstract

Composite LiFe_0.4Mn_0.6PO₄/C microspheres are considered advanced cathode materials for electric vehicles and other high-energy density applications due to their advantages of high energy density and excellent cycling stability. LiFe_0.4Mn_0.6PO₄/C microspheres have been produced using a double carbon coating process employing traditional industrial techniques (ball milling, spray-drying and annealing). The obtained LiFe_0.4Mn_0.6PO₄ microspheres exhibit a high discharge capacity of around 166 mA h g⁻¹ at 0.1 C and excellent rate capabilities of 132, 103, and 72 mA h g⁻¹ at 5, 10, and 20 C, respectively. A reversible capacity of about 152 mA h g⁻¹ after 500 cycles at a current density of 1 C indicates an outstanding cycling stability. The excellent electrochemical performance is attributed to the micrometer-sized spheres of double carbon-coated LiFe_0.4Mn_0.6PO₄ nanoparticles with improved electric conductivity and higher Li ion diffusion coefficients, ensuring full redox reactions of all nanoparticles. The results show that the advanced high-energy density cathode materials can be produced using existing industry techniques.