Applied Surface Science, Vol.316, 348-354, 2014
Zirconium phosphate wrapped LiMn1.5Ni0.5O4 used in lithium ion batteries as high voltage cathode material
To solve the major problem of interfacial side reactions between LiMn1.5Ni0.5O4 (LMNO) and liquid electrolyte at high voltages, zirconium phosphate (ZrP) wrapped cathode material LMNO@ZrP, with different aspect of ZrP in 2 wt% and 4 wt%, have been prepared by a hydrothermal method. In particular, we focus on the distribution of ZrP on the LMNO surface to find out the optimal coating material and amount. The effects of ZrP coating layer have been investigated by comparison of the properties of the ZrP coated LMNO (LMNO@ZrP) and pristine LMNO electrodes by several electrochemical characterizations. The electrochemical impedance spectroscopy results show that LMNO@ZrP-3M-2 electrode exhibits an improved electrochemical property of suppressing the impedance increase. In the cell life test, LMNO@ZrP-3M-2 electrode shows a high capacity retention of 94.6% after 200 cycles at 55 degrees C. (C) 2014 Elsevier B. V. All rights reserved.
Keywords:Lithium nickel manganese oxides;Zirconium phosphate;Lithiumion battery;Surface modification;Longterm cyclability