摘要

Lithium rich manganese layered oxides (Li[Li0.2Mn0.54Ni0.13Co0.13]O-2) with three kinds of architectures (conventional small particles, solid spherical particles and novel hollow spherical particles) are synthesized by co-precipitation followed by calcination. Their interior architectures have been studied through observation of cross-sections, and electrochemical impedance spectroscopy (EIS) has been utilized to gain insight into their properties. Conventional small particles have a high specific surface area (3.3467 m(2) g(-1)) that may cause corrosion in an electrolyte to more easily happen on its surface. Solid spherical particles show unsatisfactory electrochemical properties that could result from the long diffusion path (can reach 10.1 mu m). Hollow spherical particles illustrate a low specific surface area (0.4648 m(2) g(-1)) and short diffusion path (about 1.5 mu m) at the same time, which enhanced their performance during the electrode process (271 mA h g(-1) of initial discharge capacity). The electrochemical performance of hollow spherical particles is significant in the development of lithium rich manganese layered oxides.