鋰離子二次電池因能量密度高、工作電壓高、成本低等優點成為現今二次電池之主流。而商用之石墨負極因理論電容量較低，取代石墨之負極材料為目前研究重點之一。
鎂具有較石墨高電容量之優勢，但因鎂活性高、安全性不佳，且在數次循環充放電後會因體積膨脹導致電池壽命不佳等問題。基於此，本實驗使用活性較低Mg-Zn-Al(ZA)合金材料作為鋰離子電池之負極材料，藉助Mg基地作為活性材料，利用第二相Mg32(Al.Zn)49來抑制體積變化，並導入奈米Ag粒子到粉末系統中，進而探討極片之顯微組織與充放電特性。
實驗結果顯示，ZA負極材料在不同工作溫度與不同電流密度下具有顯著差異之充放電性質，在高溫(55℃)、電流80mA/cm2條件下具有最高充放電容量與最佳庫侖效率。添加不同比例Ag粒子於ZA負極材料中之充放電結果顯示，隨著Ag添加量增加，可達到快速降低不可逆電容量之正面效益。
此外，實驗藉蒸鍍方式製備Ag/ZA極片，並檢討熱處理製程對極片界面擴散與氧化行為之影響，可確認蒸鍍銀膜經熱處理後之試片，電阻率下降，並具良好擴散界面與抗氧化之特性。因此，Ag粒子塗佈在粉末混合過程中，可具有Ag/ZA機械合金界面層，進而提升充放電特性。

Lithium-ion batteries have been widely applied in various electronic devices due to their higher energy density, higher working voltage and relatively lower cost than other secondary systems. However, the current choice of graphite anode for lithium-ion batteries has the disadvantages of low energy density. Thus, there has been a growing interest in developing alternative anode materials.
The theoretical specific capacity of magnesium is much higher than that of graphite, but magnesium has several disadvantages, such as high activity, low safety and severe volumetric expansion during lithiation/delithiation processes, which greatly limits the cycle life of the electrodes. In this study, Mg-Zn-Al(ZA) alloy was performed as the anode materials of lithium-ion batteries, Mg-based structure was used as the active materials, and utilizing the second phase Mg32(Al.Zn)49 to inhibit the volumetric changes. Meanwhile, adding nano- scale Ag particles into the powder systems, and then their microstructures and charge-discharge characteristics were investigated.
The results indicated that the ZA anode materials had the significant differences in working temperature and current density. It had the highest discharge capacity and the best coulomb efficiency at 55℃ and 80mA/cm2. Furthermore, the effects on adding Ag particles with different ratio into ZA anode materials showed that it was able to rapidly reduce the irreversible capacity and enhance cycle performance.
In addition, Ag/ZA electrodes were performed by thermal evaporation, and the results of interface diffusion and oxidation behavior by heat treatment were discussed. It was confirmed that after heat treatment, Ag/ZA electrodes formed good diffusion behavior and anti-oxidation property. Therefore, Ag/ZA had mechanical alloy interface layer by coating Ag particles, and then enhanced the charge-discharge characteristics.

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