Identification the impact of carbon addition on phase formation and electrochemical performance of LiFePO4/C synthesized from ferronickel-derived FePO4

作者：Vita Astini, A. Z. Syahrial, A. Subhan, Johny Wahyuadi Mudaryoto Soedarsono · 发表于：Eastern-European Journal of Enterprise Technologies · 年份：2026 · DOI：10.15587/1729-4061.2026.365363

The object of this study was LiFePO4/C cathode material synthesized using a ferronickel-derived FePO4 precursor, with the main focus is the effect of carbon addition on phase formation and electrochemical performance. The problem was how carbon addition affects olivine LiFePO4 phase formation, impurity suppression, microstructure, and electrochemical performance when a non-commercial ferronickel-derived iron precursor is used. The precursor was mixed with LiOH as a lithium source and varying amounts of carbon from Super P: 5 wt.%, 7 wt.%, and 9 wt.%. Carbon addition influenced the formation of olivine LiFePO4. At 7 wt.% LFP/C, the diffraction pattern was dominated by the LiFePO4 phase, around 99.60% based on Rietveld refinement. The absence of detectable Ni by EDX suggests that Ni carryover from the ferronickel-derived precursor was minimized. The results suggest that ferronickel-derived FePO4 can be used as a precursor for LiFePO4/C synthesis, and carbon addition promotes phase development with 7 wt.% as the optimum composition. The results can be practically used as a basis for developing value-added LiFePO4/C cathode materials from ferronickel-derived iron resources under controlled synthesis conditions, particularly when the FePO4 precursor purity is maintained, Super P carbon is used in the range of 5–9 wt.%, and the material is processed by ball milling, preheating at 300°C, and calcination at 650°C under an argon atmosphere. The 7 wt.% LFP/C sample had a specific capac...