Nanostructured Hybrid Layered-Spinel Cathode Material Synthesized by Hydrothermal Method for Lithium-Ion Batteries

摘要

Nanostructured spinel LiMn_(1.5)Ni_(0.5)O4, layered Li_(1.5)Mn_(0.75)Ni_(0.25)O_(2.5) layered-spinel hybrid particles have been successfully synthesized by hydrothermal methods. It is found that the nanostructured hybrid cathode contains both spinel and layered components, which could be expressed as Li_(1.13)3Mn_(0.75)Ni_(2.25)O_(2.32). Diffraction-contrast bright-field (BF) and dark-field (DF) images illustrate that the hybrid cathode has well dispersed spinel component. Electrochemical measurements reveal that the first-cycle efficiency of the layered-spinel hybrid cathode is greatly improved (up to 90%) compared with that of the layered material (71%) by integrating spinel component. Our investigation demonstrates that the spinel containing hybrid material delivers a high capacity of 240 mAh g~(-1) with good cycling stability between 2.0 and 4.8 V at a current rate of 0,1 C.