The electrochemical behavior of a SiOx-graphite composite anode with a diamond-like carbon (DLC)-Cr double-layer coating and employed in a Li-ion secondary cell was studied to determine whether the coating improved the electrochemical characteristics of SiOx. The DLC layer was coated through plasma-enhanced chemical vapor deposition, and the Cr layer was formed by physical vapor deposition. The formation of the coating layer was confirmed by transmission electron microscopy, Raman spectroscopy, and electron microprobe analysis. The charge capacity of a coated-anode cell (591 mA·h· g-1) was found to be higher than that of a bare-anode cell (517 mA·h·g-1) after the 1st cycle. Further, the 50th-cycle capacity retention of the coated-anode cell (83%) was higher than that of the bare-anode cell (59%) at a 0.5 C-rate. The electrochemical characteristics of the coated-anode cell were investigated by impedance analysis, energy-dispersive X-ray spectroscopy, and scanning electron microscopy. Because of good mechanical properties of the DLC-Cr coatings and high electrical conductivity of Cr, double layer coating enhances the electrochemical behavior of SiO x as a supplementary coating material.
Bibliographical noteFunding Information:
This study was supported by a National Research Foundation (NRF) of Korea grant (2011-0028757) funded by the Ministry of Education, Science, and Technology (MEST) of the Korean government. A transmission electron microscope located at the Korea Basic Science Institute, Seoul Center, was used for observing the microstructures of samples.
- Diamond-like carbon
- Double layer
- Lithium-ion battery
- Silicon monoxide
ASJC Scopus subject areas
- General Chemical Engineering