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The high nickel ternary LiNi${}_{0.8}$Co${}_{0.1}$Mn${}_{0.1}$O₂ (NCM811) cathode material has attracted much attention owing to its advantages of high capacity and low price. However, NCM811 suffers from surface side reactions and cation mixing, which results in an unstable crystal structure and lower Coulomb efficiency and capacity in lithium ion batteries. In this work, Mo-doped cathode material NCM811 is effectively synthesized by high-temperature solidification approach. The characterization results show that the doped NCM811 can form a coating layer on the surface, preventing electrolyte side reactions with the electrode. As the cathode for lithium ion batteries, the Mo-doped NCM811 electrode shows an initial discharge capacity of 185.21mAh/g and obtains 156.33mAh/g with a capacity retention of 84.5% after 100 cycles at 1C. This study provides a simple and reliable method of fabricating high-performance NCM811 cathode materials.

The microstructures and mechanical properties of Ni_50-xTi_43+xAl₆Mo₁ (x= 0.5, 1, 1.5, 3.5, 5.5 and 7 at. %) alloys have been investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and compressive tests. We found that the variation of Ni/Ti ratio is the predominant reason for affecting the yield stress. The yield stress at room temperature of Ni-rich and Ti-rich alloys was higher than that of the equi-atomic alloy due to the strong solid solution hardening caused by the variation of Ni/Ti ratio. The size and volume fraction of Ti₂Ni phase decreased with increasing Ni/Ti ratio. The yield stress at 600°C and 700°C increased with the increasing volume fraction of Ti₂Ni phase due to the precipitation hardening effect. The precipitation hardening effect was weakened with increasing temperature. For the Ti-rich alloy deformed at 800°C, the yield stress deceased with the increasing of Ni/Ti ratio due to the reduced strength and unfavorable distribution of Ti₂Ni.