Investigation on LiNi0.5Mn1.5O4 cathode material based on the precursor of nickel-manganese compound for lithium-ion battery

The high-voltage spinel LiNi0.5Mn1.5O4 (LNMO) with submicron particle size (LNMO-8505P70010) has been synthesized based on nickel-manganese compound, which is obtained from pre-sintering the nickel-manganese hydroxide precipitation at 850 °C. The LNMO materials based on nickel-manganese hydroxide (LNMO-70010, LNMO-850570010, and LNMO-8501070010) have also been synthesized for comparison to study the pre-sintering impact on the properties of LiNi0.5Mn1.5O4 material. The morphologies and structures of the obtained samples have been analyzed by X-ray powder diffraction and scanning electron microscopy. The nickel-manganese compound has a spinel structure with high crystallinity, making it a good precursor to form high-performance LNMO with lower content of Mn3+ and impurity. The obtained LNMO-8505P70010 delivers discharge capacities of 125.4 mA h g−1 at 0.2 C, and the capacity retention of 15 C reaches 73.8 % of the capacity retention of 0.2​ C. Furthermore, it shows a superior cyclability with the capacity retention of 96.4 % after 150 cycles at 5 ​C. Compared with the synthesis method without pre-sintering, the synthesis method with pre-sintering can save energy while reaching the same discharge specific capacity.