Titanium-doped lithium cobalt oxides having the formula LiTixCo1-xO2 (0 ≤ x ≤ 0.5) have been synthesized using high temperature solid-state technique and its performance in a lithium rechargeable cell is reported. The synthesized oxides were structurally analyzed using X-ray diffraction (XRD) and Raman spectroscopy. It has been observed that single-phase materials were below 10% of Ti doping whereas impurity spinel phases were detected at higher concentrations. Electrochemical behaviors of the prepared powders were analyzed using cyclic voltammetry (CV) and galvanostatic charge/discharge cycling studies in the voltage range 3.0-4.25 V (vs. Li metal) using 1 M LiClO4/PC as electrolyte. The composition with x = 0.01 exhibits an initial charge and discharge capacity of 157 and 148 mA h/g at 0.2C rate, respectively, as compared to 137 and 134 mA h/g of LiCoO2. Further, more than 90% of the capacity is retained even after 10 cycles. The role of tetravalent doping on the electrochemical behavior of LiCoO2 has not been reported previously.
Bibliographical noteFunding Information:
One of the authors, GK, would like to thank KOFST, Seoul, Korea, for offering a Brain Pool Visiting Fellowship. GK also thanks CECRI, Karaikudi and CSIR, New Delhi, for grant of leave. The authors thank the referees for their valuable suggestions. This work was also supported by the Ministry of Information and Communication of Korea (Support Project of University Information Technology Research Center supervised by KIPA). The authors would like to thank Cheil Industries Inc. for supporting electrolyte.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics