太陽能電池發電利用的是矽等半導體材料的量子效應，將太陽光譜中的可見光轉變為電能。可是矽晶片若直接暴露於大氣中，其光電轉換機能會衰減。為此採用透明，耐光老化，接著性好，能承受大氣變化且具有彈性的EVA 材料將矽晶片組包封，並和上層保護材料玻璃，下層背板材料PVF 複合膜粘合為一體，構成太陽電池模組。本研究使用VA 含量28％與VA 含量16％之EVA 樹脂做為主要材料，將光吸收劑、光穩定劑、抗氧化劑等改質劑與交聯劑充分混練於EVA 樹脂中，混練完成後進行熱壓加工成型，探討不同VA 含量組成，不同交聯劑及VA28 與VA16 依比例不同做複合混摻等EVA 封裝材料之物性。實驗上使用動態機械分析儀DMA、熱重損失分析儀DSC、萬能材料試驗機、索氏萃取法與快速耐候試驗機進行分析。實驗結果顯示，當交聯劑比例增加，材料的基本機械性質、交聯程度與光學性質隨之上升，VA16 具有較好熱穩定性、結晶性與拉伸模量。但因VA16 之EVA 材料結晶性較高，導致在光學性質上使用有一定程度的影響，故欲將VA16 較優良之性能應用在封裝材上，於是與VA28 之EVA 材料為主進行混摻動作，共混EVA 材料之大部分物理性能有得到改善，但仍以VA28 添加Lupersol TBEC 之EVA 為最佳配方，較能符合太陽能電池模組封裝材料之規格需求。

Solar cell (photovoltaic cell) generate electricity via photovoltaic effect which transferring the incident light into electric current. The silicon wafers in device expose the sunlight directly induce the decrease in photovoltaic effect. Owing to that, EVA materials are employed in solar cell encapsulation with upper protective glass and lower back material PVF film due to its high flexibility, transparency, weathering resistance and adhesion. In this study, the different VA content and cross-linker of EVA were well-mixed with absorber, stabilizer, and anti-oxidant, respectively. Then, the EVA films were obtained by hot press processing. Moreover, the investigation of the effects on the properties of different VA/cross-linker content by DMA, TGA, DSC, gel fraction determination, and weathering test in experimental. From the experimental results, the increase in cross-linker cause the increase in mechanical, crosslinking and optical properties.VA16 has better thermal stability, crystallinity, and tensile strength than those of VA28, but lower optical properties.VA28 has higher optical properties blended with Lupersol TBEC resulted in the optimum materials in solar cell encapsulation.

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