Three dimensional LiFePO4-carbon fiber structures for thin film batteries

• Main Authors: Wei-chieh Huang, 黃惟傑
• Other Authors: 邱國峰
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/86gy62

碩士 === 逢甲大學 === 材料科學與工程學系 === 103 === Recently, plasma process technology was widely used to fabricate thin film batteries. Some of the previous studies have mentioned that the electrochemical performances of thin film batteries were influenced by plasma parameters. This search used pure LiFePO4 thin films as the cathode materials for thin film batteries. LiFePO4 thin films were deposited on carbon cloth under various plasma parameters by RF magnetron sputtering, shows as three dimensional LiFePO4-carobn fiber structure. As shown in diagnostics of self bias, self bias varied with different plasma parameters. Under different self bias, the LiFePO4 thin films were deposited with various energy of depositing atoms and reflected neutrals. The surface morphology of LiFePO4 thin films were observed by scanning electron microscope, it showed obvious different morphologies under various energy of depositing atoms and reflected neutrals. X-ray diffraction (XRD) revealed that the texture of LiFePO4 thin films were influenced by various energy of depositing atoms and reflected neutrals. The LiFePO4 thin films deposited under the lowest energy of depositing atoms and reflected neutrals, which exhibit equilibrium bulk structure and a high capacity of 147 mAh/g at 0.2 C. The LiFePO4 thin film batteries show no significant capacity fading after 100 cycles at 1 C.