Double Flame-Fabricated High-Performance AlPO₄/LiMn₂O₄ Cathode Material for Li-Ion Batteries

The spinel LiMn₂O₄ (LMO) is a promising cathode material for rechargeable Li-ion batteries due to its excellent properties, including cost effectiveness, eco-friendliness, high energy density, and rate capability. The commercial application of LiMn₂O₄ is limited by its fast capacity fading during cycling, which lowers the electrochemical performance. In the present work, phase-pure and crystalline LiMn₂O₄ spinel in the nanoscale were synthesized using single flame spray pyrolysis via screening 16 different precursor-solvent combinations. To overcome the drawback of capacity fading, LiMn₂O₄ was homogeneously mixed with different percentages of AlPO₄ using versatile multiple flame sprays. The mixing was realized by producing AlPO₄ and LiMn₂O₄ aerosol streams in two independent flames placed at 20° to the vertical axis. The structural and morphological analyses by X-ray diffraction indicated the formation of a pure LMO phase and/or AlPO₄-mixed LiMn₂O₄. Electrochemical analysis indicated that LMO nanoparticles of 17.8 nm (d _BET) had the best electrochemical performance among the pure LMOs with an initial capacity and a capacity retention of 111.4 mA h g^-1 and 88% after 100 cycles, respectively. A further increase in the capacity retention to 93% and an outstanding initial capacity of 116.1 mA h g^-1 were acquired for 1% AlPO₄.