鋰離子電池是相當重要的儲能設備，其應用範疇以及使用量，都不斷的持續增加，然而，鋰離子電池的性能一直無法顯著的提升，主要是因為陽極材料的發展相當相當緩慢。現今鋰離子電池約有99%依然使用石墨作為陽極材料，石墨作為鋰離子電池活性材雖然有相當好的穩定性，但是電容量已不能滿足新世代3C產品以及電動車等產品的應用要求，因此當下最重要的工作，即是開發新型的陽極材料。矽有高於石墨10倍的理論電容量，因此成為候選陽極材料，但是矽在充放電過程會產生相當大的體積變化，造成陽極材料崩解、固態電解質增生，進而導致電池失效，使得矽陽極鋰離子電池無法實際應用。雖然有許多文獻，利用奈米線結構、表面修飾、或特殊的電極板結構設計等方法，想要克服矽電極劇烈體積膨脹的問題，但是效果仍然有限。原因可能是對於矽電極充放電過程的結構變化，仍然不夠清楚。
因此，本研究製作矽奈米球殼，作為鋰離子電池的陽極材料。先利用鎂蒸氣將二氧化矽奈米球表面還原，再經過酸洗及退火處理得到奈米矽球殼，之後進行XPS、EDX化學成分分析，TEM、SEM厚度及形貌觀察，XRD結構分析，以及電性、化性量測。實驗結果證實，以合成出來的奈米矽球殼作為鋰離子電池的陽極，有效提升電池效能以及穩定性。這主要是因為中空的奈米球殼結構，可以有效地提供體積膨脹空間，避免發生電極材料崩解等問題。
為了探討矽鋰離子電池的嵌/脫鋰的機制以及詳細的結構變化，我們利用利用同步輻射光源技術做更進一步探討。由X光吸收光譜及粉末繞射光譜證實，充/放電過程發生的結構變化，主要是由鋰離子造成矽結構斷鍵所主導。

Nowadays, Li-ion batteries are important on energy storage but most of appliances are
still using traditional materials as the electrode. For instance, graphite is widely applied to
99% of Li-ion batteries despite the theoretical capacity just 372 mAh/g.
Silicon has a large theoretical capacity and it make it an attractive anode material, but
volume expansion during cycling and an unstable Solid electrolyte interphase(SEI) has
consume lithium source led to irreversible capacity increase.
Artificial nanostructure is effectively to overcome the issue of volume expansion,
therefore, this work aim to realize controllable synthesis of hollow spherical shell base on
Silicon from common and easily accessible silica nanoparticles and magnesiothermic
reduction and to study their morphology (TEM,SEM) components (EDX,XPS), structure
(XRD,XAS), electrochemical performance as an anode of lithium-ion batteries (LIBs) and ex-situ X-ray studying.
By using Double wall silicon spherical shell as anode material for lithium-ion batteries, electrochemical performance shows much better than commercial silicon powder, then we used ex-situ techniques based on XRD and XRD, the experiment result shows Lithium ion
breakdown Si-Si bonding and Si have two phase reaction between Si and LixSi(x<=3.75) during cycling.

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