Temperature-mediated synthesis of FePO4 towards enhanced electrochemical performance of LiFePO4 cathodes

The quality of iron(III) phosphate (FePO 4 , FP), a critical precursor for lithium iron phosphate (LiFePO 4 , LFP) cathodes, is paramount to the electrochemical performance of LFP. However, conventional industrial FP often suffers from irregular morphology, broad size distribution, and severe agglomeration, which limit LFP performance. To address this issue, we developed a temperature-mediated liquid-phase precipitation method for the controllable synthesis of FP precursors and systematically investigated how the precipitation temperature influences the properties of the precursors and, in turn, determines the electrochemical performance of the resulting LFP material. The optimized FP obtained at 80 °C exhibits uniform spherical particles, a narrow size distribution, excellent dispersibility, a near-theoretical Fe/P ratio, and high purity. Consequently, the derived LFP cathode demonstrates enhanced crystallinity, reduced particle size, and improved dispersion, leading to superior electrochemical properties. It delivers an initial discharge capacity of 161.63 mAh·g −1 at 0.1C and maintains 141.48 mAh·g −1 after 100 cycles at 1C, corresponding to a 97.20% capacity retention. The material also showcases outstanding rate performance, high reversibility, and low charge-transfer resistance. This work provides a robust and scalable strategy for producing high-quality FP precursor and high-performance LFP cathodes, contributing to the advancement of lithium-ion battery technology.