Abstract
The growing demand for efficient energy storage in electric vehicles and grid-level systems has intensified research into high-performance, sustainable, and cost-efficient Lithium-ion Battery (LiB) cathodes. Among these, lithium nickel manganese oxide (LiNi0.5Mn1.5O4; LNMO) spinels are particularly promising due to their high operating voltage (~4.7 V), favorable theoretical capacity (~147 mAh g⁻¹). However, conventional manganese production routes (submerged arc furnace and electrolytic manganese metal processing) are energy-intensive and carry a substantial CO2 footprint, motivating the search for greener precursor pathways. This study reports the synthesis and characterization of LMO and LNMO cathode materials derived from a manganese oxide precursor produced by Calix Flash Calcination (CFC), a proprietary technology in which MnCO₃ is rapidly calcined at high heating rates to yield a hierarchically porous, nanocrystalline MnxOy intermediate. CFC-derived cathodes were benchmarked against equivalent materials prepared from commercial Mn3O4 (COM) using identical incipient wet-synthesis, ball-milling, and calcination protocols. Comparative analysis revealed that the ten-fold BET surface area advantage of the CFC precursor (87.4 vs. 8.8 m2 g-1) propagates through synthesis to yield spinel products with four- to six-fold higher surface areas, smaller crystallites, and narrower size distributions. Powder X-ray diffraction confirmed the formation of single-phase cubic spinel in all samples, while scanning electron microscopy revealed distinct morphological differences driven by precursor selection. Electrochemical testing showed that CFC-derived LMO delivers 120.3 mAh g⁻¹ at 1C, a 44% improvement over COM-LMO (83.6 mAh g⁻¹) and exceeding a commercial LMO reference (111.8 mAh g⁻¹), while CFC-derived LNMO delivers 135.7 mAh g⁻¹ at 1C, outperforming COM-LNMO and two commercial LNMO benchmarks. Both CFC materials exhibit superior rate capability up to 20C and near-complete capacity recovery after high-rate stress cycling.