Fine Structure and Electrochemical Performance Investigations of Spherical LiMn_0.6Fe_0.4PO₄/C Cathode Material Synthesized via a Spray-Drying Route at Various Calcination Temperatures

Abstract

LiMn_<i>x</i>Fe_1-<i>x</i>PO₄/C is characterized by excellent multiplicative performance and high operating voltage, and as a type of cathode material, it has a high electronic conductivity and thus has received much attention. In this paper, carbon-coated LiMn_0.6Fe_0.4PO₄/C was synthesized using glucose + PEG2000 as the carbon source by wet sanding and spray-drying. The experimental results show that the use of sanding and the spray-drying method can make the particle size distribution of LiMn_0.6Fe_0.4PO₄/C powder more uniform. The initial discharge specific capacity of the LiMn_0.6Fe_0.4PO₄/C battery was 144.3 mA h g^-1, and after 100 cycles at 1 C current, the discharge specific capacity of the battery remained at 128.2 mA h g^-1 with a cycling efficiency of 94.3%. At the same time, the oxidation states and coordination environments of the elements Fe and Mn were elucidated by X-ray absorption fine structure spectroscopy. And the ex-Fe-MS was tested under different charging and discharging conditions. The sample optimized by the orthogonal test has good cycle stability and multiplication performance.