| Summary: | 碩士 === 大同大學 === 材料工程學系(所) === 94 === Spinel LiMn2O4 was prepared via electrostatic spray deposition (ESD) method and followed by heat-treatment at various temperatures for various durations. The compositions, crystalline and morphology of the electrodes were investigated with ICP, XRD and SEM. The electrochemical properties of thus prepared electrodes were studied by capacity retention studies. These kind of electrode do not contain any binder or conductive. They are good for solid-electrolyte interface (SEI) studies. In this study, FTIR was used to investigate the SEI formed. It is found that Li2CO3 forms on the spinel electrode before cycling. However, no significant change on the electrode film was found by the image obtained by hard X-ray. The Li2CO3 disappeared as the coin cell was charged to 4.1 V. Compounds containing Li2CO3 and (－(CO)OO(CO)－) functional group appeared as the coin cell was discharged to 3.7 V. After that, Compounds containing Li2CO3 and (－(CO)OO(CO)－) functional group appeared/disappeared periodically as the cells discharged/charged to 3.7 V and 4.1 V, respectively.
|
|---|
