Process and properties of the carbon nanotube assisted LiCoO(2) thin-film battery electrode by pulsed laser deposition

Abstract

In this study, a pulsed laser deposition process was developed to deposit a carbon nanotube (CNT) assisted LiCoO(2) electrode to improve its power density. The electrodes were deposited on Pt-coated Si substrates with Ar and O(2) as sputtering gases and LiCoO(2)+C as the target. The results indicate that the working pressure is the most important parameter to control the composition of the electrode. Therefore, electrodes with a three-layer structure (i.e., LiCoO(2)-rich/CNT-rich/LiCoO(2)-rich) were fabricated by a three-step deposition process by varying the pressures from 13 to 1.3x10(4) Pa and then 13 Pa again, and it was found that the charge/discharge capacity became approximately 1.5 times greater than that in the corresponding electrode without a CNT-rich layer. The results also indicate that a higher substrate temperature is favorable for improving the crystallinity of the electrode to approach LiCoO(2) crystals.