Electrochemical performance of zirconium doped lithium rich layered Li1.2Mn0.54Ni0.13Co0.13O2 oxide with porous hollow structure

Lithium rich manganese layered oxides (Zr doped Li[Li0.2Mn0.54Ni0.13Co0.13]O-2) with porous hollow structure are synthesized by co-precipitation followed by calcination. The morphologies of bare materials and electrodes have been studied through scanning electron microscope (SEM), which illustrates that particles with porous hollow structure combine with conductive carbon more efficiency. Additionally, the porous hollow structure provide a three dimensional space for lithium ion diffusion. Electrochemical impedance spectroscopy (EIS) and Transmission electron microscopy (TEM) have been utilized to gain insight to the properties of pristine and Zr doped materials before and after electrode process. Zr doped Li[Li0.2Mn0.54Ni0.13Co0.13]O-2 with porous hollow structure shows better crystal stability and higher diffusion coefficients (D) of the lithium ions diffusing. After 100 cycles at 250 mAg(-1), the lattice parameter and crystal structure of Zr doped materials shows smaller changes than pristine's, and the lithium ion diffusion of pristine and Zr doped material decreased from 1.89 x 10(-4) and 2.73 x 10(-4) mA cm(-2) to 3.18 x 10(-5) and 1.66 x 10(-4) mA cm(-2), respectively. (C) 2015 Elsevier B.V. All rights reserved.