Facile synthesis and performances of nanosized Li2TiO3-based shell encapsulated LiMn1/3Ni1/3Co1/3O2 microspheres†
LiMn1/3Ni1/3Co1/3O2 microspheres covered by a nanosized Li2TiO3-based shell are prepared by a facile synthesis method. First, a controllable TiO2 nano-layer is grown on the surface of a spherical Mn1/3Ni1/3Co1/3CO3 precursor, and then the resultant TiO2@LiMn1/3Ni1/3Co1/3O2 hybrid is synchronously transformed in situ into a hierarchical Li2TiO3@LiMn1/3Ni1/3Co1/3O2 microsphere through a solid-phase reaction. It has been found that the hierarchical Li2TiO3@LiMn1/3Ni1/3Co1/3O2 microspheres exhibit a good rate capability with a discharge capacity of 92.3 mA h g−1 even at higher rates of 20 C between 3.0 and 4.3 V. Besides, they possess excellent cyclic stability especially at high rates, with a capacity retention of 90.3% after 500 cycles at a 20 C rate. The enhanced electrochemical performance of the hierarchical Li2TiO3@LiMn1/3Ni1/3Co1/3O2 at high rates is attributed to the stable and fast Li+-conductor characteristic of the nanosized Li2TiO3-based shell. Thus, the Li2TiO3@LiMn1/3Ni1/3Co1/3O2 microspheres will be a promising cathode material for lithium-ion batteries with high power density and excellent cycling performance.