This study investigates the influence of various manganese sources—specifically MnCO3, Mn3O4, and MnO2—on the performance of lithium manganese iron phosphate (LMFP) synthesized through a combined spray-drying and chemical vapor deposition (CVD) strategy. The synthesis protocol involved the initial formation of a precursor through the co-sintering of manganese, phosphorus, iron, and dopant sources via CVD, followed by secondary spray-drying and carbon thermal reduction with Li2CO3 and carbon additives. Morphological analysis via Scanning Electron Microscopy (SEM) and laser diffraction indicates that Mn3O4-derived LMFP possesses highly spherical secondary structures comprising well-crystallized, uniformly distributed primary particles. Elemental mapping via Energy Dispersive Spectroscopy (EDS) confirms a homogeneous distribution of stoichiometric elements without localized segregation, alongside the successful lattice integration of dopants. In contrast, the MnCO3-derived samples exhibited deleterious carbon accumulation on the primary particle surfaces. Consequently, the Mn3O4-based LMFP demonstrated superior electrochemical kinetics, delivering a remarkable initial discharge capacity of 148.9 mAh g−1 at 1C, with an exceptional capacity retention of 97.9% after 100 cycles. These findings underscore the critical role of precursor selection in optimizing the interfacial and bulk properties of high-performance LMFP cathodes.
S et al. (Sat,) studied this question.