AlF[sub 3]-Coating to Improve High Voltage Cycling Performance of Li[Ni[sub 1∕3]Co[sub 1∕3]Mn[sub 1∕3]]O[sub 2] Cathode Materials for Lithium Secondary Batteries

Abstract

powders were modified by coating their surface with amorphous as a new coating material. The -coated electrode showed improved cycle performance and rate capability under a high cutoff voltage range of 4.5 and . AC impedance results showed that the -coated has stable charge transfer resistance regardless of the cycle number. Electron diffraction analysis also showed that no structural transition of the primary particles was observed for the -coated electrode. Electrochemical impedance spectroscopy and electron microscopy indicate that coating plays an important role of stabilizing the interface between cathode and electrolyte.