在鋰離子電池的負極材料中，矽電極能提供相當高的理論電容量，是目前商業化石墨電極材料的十倍以上，但其充放電時，體積變化大，因此易造成電極的破壞，近期間，相關的研究中透過矽材料結構的奈米化以及表面改質的方式包覆導電材料於表面，來減緩體積改變所造成的影響並提高矽材料的導電性，而電池的電容量以及循環壽命確實有了明顯改善，但至目前為止仍無有效的分析方式能對經表面改質後的矽原材料粉末來進行量測分析，獨立出表面改質製程對電池表現的影響。
本研究中，將利用原子力顯微鏡對材料表面具有高解析度的優勢，結合Kelvin Probe Force Microscopy (KPFM)、Electrostatic Force Microscopy (EFM) 與 Conductive Atomic force Microscopy (CAFM)三項表面電性分析技術，於自製手套箱中的低溼度環境下，針對光宇材料所提供經表面碳改質處理的矽材料粉末進行掃描，得到粉體的表面形貌、表面電位、靜電力以及電流等資訊。
從KPFM表面電位的量測結果，可以換算成粉體的表面功函數，粉體的功函數範圍與其標準差越小，代表表面生成的物質越相近，均勻性越高，而功函數的數值也可以推測其表面生成的物質，最後並透過X射線光電子能譜儀加以驗證，此外，若在粉體的製備過程中表面產生缺陷、有機物的殘留抑或是氧化物的生成，皆會侷限電荷的移動，透過EFM表面靜電力的量測，能推得表面電荷的分佈情形並定位出電荷集中處，進而討論造成缺陷的原因，接著，藉由CAFM量測的表面電流大小，比較各粉體的導電性，並搭配掃描式電子顯微鏡觀察粉體的造粒情形，最後再與台南大學張家欽教授團隊所提供各粉體的電池充放電測試資料進行結果比較。
我們發現G16粉體的表面均勻性雖然最好，但其造粒的結果顆粒大小不一，且表面具有大型孔洞，造成粉體於組裝電池時破碎，充放電表現不佳，而G17粉體的表面均勻性雖然最差，但因為其表面生成了許多一氧化矽，能與鋰離子進行可逆反應並使得電容量比其他粉體高，而相較於M系列粉末，G系列粉末導電性較佳，M系列粉末容易於組成電池後有內阻過大的問題，導致充放電表現不佳，而表面電荷的分佈則受各粉體的表面形貌以及表面改質的生成物所影響，與造粒的製程有關。
綜合所有的分析結果，碳矽粉末若能採用G16粉體的表面改質製程，提高均勻性，並在製程中藉由控制部分氧氣參與反應，於矽電極原料粉末表面生成一氧化矽以提高電容量，並參考M1R的造粒方式，將使得該材料的充放電效能達到最佳化。
相較於傳統研究鋰離子電池材料的方式，此分析程序從電池的電極原料粉末切入，能確實分析各製程以及對粉體造成的影響，有助於提升鋰離子電池原料粉末的品質管理，最後並將影響電池表現的因素獨立討論，可以針對該因素進行改善，並能在組成電池前預測粉體的充放電表現，大量節省新材料的開發時間。

The objective of this study is to evaluate the advantages and disadvantages of raw electrode powders before cell test. We applied three electrical AFM measurements, Kelvin Probe Force Microscopy (KPFM), Electrostatic Force Microscopy (EFM) and Conductive Atomic Force Microscopy (CAFM) in our homemade glove box at about 5% relative humidity to characterize the surface electrical properties of powders. For the KPFM results, we can calculate surface work function of powders from the distribution of their surface potential and know the surface uniformity of each powder. The surface of G16 powder is much homogeneous than others. This results are also agree with XPS (X-ray photoelectron spectroscopy) fitting data. Form the EFM images, we can localize defects on the surface of powder by the different phase shift. These defects might be caused by the surface uniformity of powders or the dangling bonds of some compounds on the surface. CAFM images showed the current intensity of each powder. Consider the current area of powders, we can get the effective current on each powder. We find that the conductivity of G series powder is much higher than M series powder. After measurement, we connect these features to the results of cell test and establish the relationship between raw material and their battery performance. In this study, results from AFM electrical measurements should be useful for improving manufacture process, also applied much simple and efficiency method to measure material directly.

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