Submicron LiFe1−yMnyPO4 solid solutions prepared by mechanochemically assisted carbothermal reduction: The structure and properties

Abstract Homogeneous submicron carbon-coated LiFe 1− y Mn y PO 4 solid solutions in the whole concentration range (0 ≤  y  ≤ 1) were obtained by mechanochemically assisted carbothermal reduction of Fe 2 O 3 and MnO 2 , using high-energy planetary mill. The samples were studied through a combination of several techniques: XRD, TEM, FTIR, Mossbauer, 6,7 Li and 31 P NMR spectroscopy and magnetic measurements. NMR study and magnetic measurements revealed the presence of tiny amounts of structural defects and ferromagnetic-like impurities with a Curie temperature above RT differing upon the sample composition. Electrochemical cycling of as prepared LiFe 1− y Mn y PO 4 showed that, despite high homogeneity and fine particles, noticeable capacity loss is observed with increased Mn content, mainly in the Mn 2+ /Mn 3+ range.