Nb-doped and Al 2 O 3 + B 2 O 3 -coated granular secondary LiMn 2 O 4 particles as cathode materials for lithium-ion batteries.

In this work, to improve the cyclability and high-temperature performance of cubic spinel LiMnO (LMO) as cathode materials, Nb-doped LiMnO powders coated and uncoated with AlO and/or BO were synthesized the modified solid-state reaction method. It was found that Nb-doped and BO + AlO-coated LMO powders comprising 5 μm granular agglomerated fine primary particles smaller than 350 nm in diameter exhibited superior electrochemical properties with initial discharge capacity of 101.68 mA h g; we also observed capacity retention of 96.31% after 300 cycles at room temperature (RT) and that of 98% after 50 cycles at 55 °C and 1C rate.