1. Enhancement of electrochemical performance of LiNi1/3Co1/3Mn1/3O2 by surface modification with MnO2.
- Author
-
Guo, Xin, Cong, Li-Na, Zhao, Qin, Tai, Ling-Hua, Wu, Xing-Long, Zhang, Jing-Ping, Wang, Rong-Shun, Xie, Hai-Ming, and Sun, Li-Qun
- Subjects
- *
X-ray diffraction , *SCANNING electron microscopes , *TRANSMISSION electron microscopes , *ELECTROCHEMISTRY , *VOLTAMMETRY - Abstract
LiNi 1/3 Co 1/3 Mn 1/3 O 2 is successfully coated with MnO 2 by a chemical deposition method. The X-ray diffraction (XRD), scanning electron microscope (SEM) and high resolution transmission electron microscope (HRTEM) results demonstrate that MnO 2 forms a thin layer on the surface of LiNi 1/3 Co 1/3 Mn 1/3 O 2 without destroying the crystal structure of the core material. Compared with pristine LiNi 1/3 Co 1/3 Mn 1/3 O 2 , the MnO 2 -coated sample shows enhanced electrochemical performance especially the rate capability. Even at a current density of 750 mA g −1 , the discharge capacity of MnO 2 -coated LiNi 1/3 Co 1/3 Mn 1/3 O 2 is 155.15 mAh g −1 , while that of the pristine electrode is only 132.84 mAh g −1 in the range of 2.5–4.5 V. The cyclic voltammetry (CV) and X-ray photoelectron spectroscopy (XPS) curves show that the MnO 2 coating layer reacts with Li + during cycling, which is responsible for the higher discharge capacity of MnO 2 -coated LiNi 1/3 Co 1/3 Mn 1/3 O 2 . Electrochemical impedance spectroscopy (EIS) results confirmed that the MnO 2 coating layer plays an important role in reducing the charge transfer resistance on the electrolyte–electrode interfaces. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF