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MnO2 nanowires were used to synthesize the spinel-type LiMn1.45Ni0.45Cr0.1O4 (Cr–LMN) materials by solid-state impregnation. Structural analyses revealed that the final product consisted of sub-micrometric Cr–LMN particles of octahedral shape well-crystallized in the cation-disordered phase. This powder delivered a specific capacity ~127 mAh g−1 up to 2C rate. At 5C rate, the capacity was still 115 mAh g−1 without significant capacity loss in 25 cycles. The remarkable improvement in electrochemical properties with respect to prior works suggests that the sub-micrometric Cr–LMN prepared by this synthesis process is a promising cathode material for high power and long-cycle lithium-ion batteries. Keywords: Li-ion batteries, 5-V electrode material, Impregnation method, Nanowires

LiFePO4(LFP)-coated sulfur (S-LFP) particles were synthesized using a dry mechano-fusion method and electrochemically tested in a liquid electrolyte. This synthesis process (encapsulation) is completed in a few minutes without a solvent drying step, thus it is easily scalable for volume production. The S-LFP cathode showed an initial capacity of 1200 mAh/g at 0.1 C, and 80% capacity retention after 90 cycles at 0.5 C. 417 Wh/kg in specific energy and 623 Wh/l in energy density are achievable with this new technology. The results suggest that the LFP layer enhances the utilization of active sulfur and lowers the polarization for oxidation of Li2S2/Li2S. Keywords: Lithium/sulfur battery, Core–shell composite, LiFePO4, Mechano-fusion, Encapsulation