Enhanced Electrochemical Performance of LiNi0.8Co0.1Mn0.1O2 Cathode Material for lithium ion batteries by WO3 surface coating
Cong Xiong, Haikou Fu, Lijue Wu, Gaoqing Yuan
Abstract
LiNi 0.8 Co 0.1 Mn 0.1 O 2 cathode material was successfully modified by using a wet-chemical route to coat WO 3 . The microstructures, morphologies, crystal structures, elemental distributions and ionic valence of the prepared cathode materials were carefully analyzed by SEM, EDS, TEM, HRTEM, XRD and XPS. The results indicated that the surface of LiNi 0.8 Co 0.1 Mn 0.1 O 2 was uniformly covered by WO 3 particles, and a small amount of W 6+ could enter to the lattice of LiNi 0.8 Co 0.1 Mn 0.1 O 2 . The WO 3 coating could prohibit the corrosion of HF and some side reactions for the cathode material during long cycles, thus greatly improving the electrochemical performance and the structural stability of LiNi 0.8 Co 0.1 Mn 0.1 O 2 . Among the examined LiNi 0.8 Co 0.1 Mn 0.1 O 2 cathode materials, 1.0 wt% WO 3 -coated LiNi 0.8 Co 0.1 Mn 0.1 O 2 has the best initial discharge capacity (185.1 mAh g -1 ) and an excellent capacity retention (93.2%) after 100 cycles at 1 C.