Short-Process Spray-Drying Synthesis of Lithium Iron Phosphate@Carbon Composite for Lithium-Ion Batteries

LiFePO4 is a promising cathode material for lithium-ion batteries. However, there are still some shortcomings in the traditional spray-drying method, such as a long production process, sophisticated production equipment, and generation of gaseous and liquid waste. To address these challenges, we propose a short-process spray-drying method for the synthesis of LiFePO4 cathode materials using a soluble Li/Fe/P source to achieve mixing at the molecular level in this paper. The results show that the prepared LiFePO4@C composite materials have a uniform carbon distribution, rapid electron/lithium-ion transport, and improved electrochemical performance. The batteries with the LiFePO4@C electrode deliver an outstanding reversible capacity and stable cycling performance. The discharge specific capacity of LiFePO4@C is approximately 60% higher than that of LiFePO4/C. The cycling discharge measurement of LiFePO4@C demonstrates a discharge specific capacity of 140 mA h/g with a capacity retention rate of 95.4% after 200 cycles at a 0.5 C rate, significantly higher than the 41 mA h/g and 59.7% for LiFePO4/C. The results suggest that the LiFePO4@C material developed using the short-process spray-drying method shows a uniform carbon coating and exhibits a superior performance. In all, this paper provides a short process, continuous production, and environmentally friendly method for the production of lithium iron phosphate.