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High-energy ball milling was employed to fabricate LiMnPO 4 coated with varying carbon ratios (3%wt, 7%wt, and 10%wt), using glucose as a carbon source. The process involved pre-milling of LiMnPO 4 precursors, followed by granulation through high-energy ball milling at 270 rpm for 2 h, and subsequent calcination at 700 °C without an inert gas flow. XRD analysis discerned the phases and structure of LiMnPO 4 , confirming the successful attainment of a single-phase LiMnPO 4 without impurities. Rietveld refinement of the XRD data elucidated the crystallographic details, affirming the material's orthorhombic olivine structure with precise lattice parameters, thereby underpinning the structural integrity essential for electrochemical applications. FE-SEM analysis revealed uniformly distributed semi-sphere particles, with sizes ranging from 130 nm for LM to 183 nm for LM-10%C. FTIR analysis delineated the internal modes of vibration in the olivine structure and verified the presence of carbon on the powder surface. Electrical measurements conducted within the frequency range of 20 Hz–100 kHz demonstrated an increase in electrical conductivity with an escalation in carbon concentration, ranging from 31 μΩ−1m−1 to 75 μΩ−1m−1 for 0%C and 10%C, respectively. A temperature-dependent study spanning 30–160 °C revealed stable electrical conductivity behavior for the samples, with a marginal increase observed at elevated temperatures. [ABSTRACT FROM AUTHOR]

Summary: High‐energy ball milling is performed on Li1.1Mn1.95Fe0.05O4 spinel material, synthesized by sol‐gel method for lithium rechargeable battery, at different durations to obtain nanopowders of finite size distributions. The powders are investigated by means of scanning electron microscopy, particle size distribution, and X‐ray diffraction (XRD) measurements. The structural analysis of the powders is performed to investigate the effect of milling on the particle size, crystallite size, and lattice strain. The scanning electron micrographs and size distribution measurements show that the particle size decreases with the increase in milling duration. The XRD results show that the widths of the diffraction peaks increase with the decrease of particle size (increase of milling duration). This broadening is analyzed according to Scherrer, Williamson‐Hall, and Halder‐Wagner methods. Peak broadening is attributed to contributions of crystallite size and lattice strain. While reducing the particle and crystallite sizes is desirable to achieve higher specific capacity and energy density of the battery active material, lattice strain leads to material degradation and a reduced capacity retention. Thus, when performing mechanical milling, lattice strain should be taken seriously into consideration to optimize the milling parameters and to enhance the materials electrochemical performance. [ABSTRACT FROM AUTHOR]