A melt casting process to make an electrochemically active LiFePnormalO4 cathode material was explored. The melting of carbon-coated LiFePnormalO4 powder at 1000°C followed by its cooling leads to a high purity LiFePnormalO4 material with excellent crystallinity and large crystals. From a detailed study on the melting of naturally occurring triphylite, elements such as Mg and Mn were easily incorporated into the olivine structure, while others such as Ca, Si, and Al were segregated into grain boundaries. Experiments also demonstrated that a variety of synthetic precursors can be used to make high purity LiFePnormalO4 materials through melt casting. The phase purity, crystallinity, and microstructures of the final product depend on the reducing conditions and the solidification process of the melt. The melt-casted material, after coarse grinding, shows good electrochemical activity.

The colourless title compound scandium(III) oxoselenate‐(IV) Sc2Se3O9 (≡Sc2[SeO3]3) was obtained by reacting a 1:3‐molar mixture of Sc2O3 and SeO2 at 830°C for seven days in an evacuated torch‐sealed silica vessel as needle‐shaped single crystals. It crystallizes hexagonally (space group: P63/m, Z = 2; a = 814.28(5), c = 764.56(4) pm, c/a = 0.939, Vm = 132.19 cm3/mol, R1 = 0.034 for 364 unique reflections) and exhibits Sc3+ cations in distorted trigonal antiprismatic coordination of six oxygen atoms (d(Sc‐O) = 202 ‐ 220 pm) all of which belong to six different isolated ψ1‐tetrahedral [SeO3]2‐ anions (d(Se‐O) = 166 ‐ 170 pm). In the crystal structure two [ScO6] octahedra share a common face to form a [Sc2O9] dimer (d(Sc···Sc) = 315 pm). The linkage of different dimers occurs only via common vertices with discrete trigonal non‐planar [SeO3]2‐ pyramids and the free non‐bonding electron pairs ("lone pairs") of the Se4+ cations occupy an empty hexagonal channel propagating along the [001] direction.

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