Thin films of LiMn2O4 have been prepared by RF magnetron sputtering on interdigitated microarray electrodes. In situ conductivity-potential profiles and cyclic voltammograms during extraction/insertion processes of Li ions were obtained simultaneously in nonaqueous and aqueous electrolyte solutions (1 M LiClO4/ propylene carbonate and 1 M LiCl/water). The electronic conductivity of Li1-xMn2O4 was found not to show metallic transition and maintain its semiconducting state during the extraction/insertion of Li ion. A slight decrease in conductivity was observed with increasing the anodic potential, i.e., with increasing x (lithium extraction) and recovered reversibly when the potential returned to the cathodic side (re-insertion of Li ions). Similar results were obtained in both aqueous and nonaqueous electrolyte solutions.
- In situ conductivity measurements
- Interdigitated microarray electrodes
- Li ion battery
- Semiconductor electrode
- Spinel-type LiMnO