High rate cyclability of nickle-doped LiNi_0.1Mn_1.9O₄ cathode materials prepared by a facile molten-salt combustion method for lithium-ion batteries

Here we employed a facile low temperature molten-salt combustion method combined with two-stage calcination process to synthesize a series of Ni-doped spinel LiNi_0.1Mn_1.9O₄ cathode materials. All the LiNi_0.1Mn_1.9O₄ materials present well-defined cubic spinel structure with a representative Fd3m space group. With the elevated calcination temperature, the particle size and crystallinity increase simultaneously. Benefiting from the optimization of calcination temperature, the LiNi_0.1Mn_1.9O₄ prepared at 600 °C reveals a favorable crystal structure and morphology consisted of homogeneous nanoparticles with a size of 90–110 nm. Consequently, the optimized LiNi_0.1Mn_1.9O₄ cathode exhibits high rate capability and ultralong cycling stability with a discharge specific capacity of 97.1 mAh g⁻¹ and a capacity retention of 63.5% after 1000 cycles at a high current rate of 10 and 25 °C. Even at a high-temperature of 55 °C, a high initial discharge capacity of 106.1 mAh g⁻¹ and a good capacity retention of 79.0% is also obtained after 100 cycles at 5 C. Such an excellent electrochemical performance together with the facile synthesis approach may endow the as-prepared LiNi_0.1Mn_1.9O₄ to be a promising practical application for high-power lithium-ion batteries.