Synthesis of LiCo1-XNiXO2 nanomaterial by hydrothermal method as cathode for lithium ion battery

Abstract

The compounds of LiCoO2 (LCO) and LiCo1-xNixO2 (LCNO), with (x=0,0.25,0.5,0.75,1) were synthesized as cathode active material for lithium–ion batteries using hydrothermal technique in this study. Structure and morphology characterization were conducted for all prepared samples. The crystalline results indicate that both LCO and LCNO possess a rhombohedral structure, while the morphology results show irregular shapes. Electrochemical tests were carried out for LiCoO2 and LiCo0.25 Ni0.75O2 samples only. From the electrochemical measurements, the LiCo0.25 Ni0.75O2 demonstrate higher charge and discharge capacities compared to the LiCoO2 electrode, findings which are consistent with the electrochemical impedance spectroscopy (EIS) results. The X-ray diffraction (XRD) results of both the prepared Lithium Cobalt Oxide (LCO) and Lithium Cobalt Nickel Oxide (LCNO) samples reveal characteristic peaks at specific angles (2θ) indicating crystallographic planes. For LCO, peaks were observed at 18.96°, 37.40°, 38.35°, 39.07°, 45.29°, 49.45°, and 59.62° corresponding to crystallographic planes (003), (101), (006), (012), (104), (015), and (107) respectively. These peaks confirm the formation of a rhombohedral LiCoO2 nanostructure with space group (R-3m no.166), consistent with standard data (JCPDS 00-016-0427). The EDX spectra of the synthesized Lithium Cobalt Oxide (LCO) and Lithium Cobalt Nickel Oxide (LCNO) were analyzed. The results showed the presence of oxygen (O), cobalt (Co), and nickel (Ni) elements. However, the peak corresponding to lithium (Li) was not visible due to its low activation energy. Finally, the synthesis and characterization of LiCoO2 (LCO) and LiCo1-xNixO2 (LCNO) compounds were conducted, with electrochemical tests indicating superior performance of LiCo0.25 Ni0.75O2 over LiCoO2