Electrospun LiMn_1.5Ni_0.5O₄ hollow nanofibers as advanced cathodes for high rate and long cycle life Li-ion batteries

High-voltage LiMn_1.5Ni_0.5O₄ spinel with one-dimensional (1D) hollow and porous architecture is fabricated via a facile single-spinneret electrospinning technique. The hierarchical porous LiMn_1.5Ni_0.5O₄ hollow nanofibers possess ∼200 nm in diameter and tens of micrometers in length, as well as a specific surface area as high as 43.2 m² g⁻¹. When served as Li-ion battery cathodes, the as-fabricated material delivers high specific capacities of 135 and 98 mAh g⁻¹ at 0.68 C and 20.4 C, respectively. Under a long-term cycling operation at 6.8 C, the cathode sustains good capacity retention of 90% after 1000 cycles. The outstanding electrochemical performance can be attributed to the porous 1D hollow nanostructure that can enlarge effective electrode/electrolyte contact areas, shorten electron/ion transport distance and accommodate volume change.