Effect of Ti4+doping on structure and electrochemical performance of LiNi0.75Mn0.25O2 cathode material
LiNi0.75 Mn0.25 O2 cathode material for lithium-ion battery is doped with Ti4+via a high-temperature solid-state method with TiO2 as additive.The doped material is characterized by means of XRD,SEM,XPS,and electrochemical tests.Results show that Ti4+can be successfully doped into LiNi0.75 Mn0.25 O2.In the range of 0≤x≤0.02 in Li[Ni0.75 Mn0.25]1-xTixO2,Ti4+doping does not change the physical phase and morphology of the material.However,it has a major impact on the electrochemical properties of LiNi0.75 Mn0.25 O2.Under the optimum Ti4+doping mole fraction amount of 1.5％,the capacity retention rate of the material increases from 87.87％to 95.42％after 50 cycles,and the discharge capacity of LiNi0.75 Mn0.25 O2 at 4C enhances from 66.47mAh·g-1 to 104.00mAh·g-1.
万方数据
