| 摘要: | 隨著科技進步和人口增長，環境和能源問題越來越受到關注。太陽能作為可再生能源之一，由於其普遍性、永久性和低污染性，成為許多國家推動綠色能源的主力。然而，太陽能板的使用壽命有限，不當處理可能對環境造成危害。因此回收及重複利用太陽能板已然成為重要的議題。太陽能板一般含有太陽能電池、鋁框架與乙烯/醋酸乙烯酯(EVA)共聚物等組件，其電池多由矽(Si)所構成。由於矽具有無毒、含量豐富、極高的理論電容量(4200 mAh/g)與低電壓平台(0.2-0.3 V)，使矽成為鋰離子電池應用中極具潛力之負極材料。然而，矽在充放電過程中會產生劇烈的體積膨脹/收縮變化，使得電容量快速衰退。為解決上述問題，本研究通過經濟有效的球磨和鍛燒處理，將太陽能板粉末再製成負極材料。藉由調整鍛燒溫度以觀察EVA殘留量，優化球磨和鍛燒的順序，製備出Si/SiOx負極材料並結合碳紙集電體應用於鋰電池中，最後定義出鍛燒500 oC後以300 rpm轉速球磨為最佳參數(500-BM(300))，於充放電100圈後擁有1170 mAh/g之電容量(200 mA/g電流密度下)。此外，因考量商用負極材料需求，將此參數應用於銅箔基材中，並透過矽基材料結合石墨進行複合製備Si/SiOx/C複合材料。結果顯示以Si/C複合比例1:0.6，並結合交聯黏著劑於充放電100圈後可擁有電容量488 mAh/g。為進一步使性能提升，於混漿時添加不同比例之乙醇作為溶劑，協助矽顆粒於漿料中的分散性，使顆粒不易團聚。結果顯示經由水：乙醇比例4：2擁有最佳之電化學性能表現，於100圈循環後擁有748 mAh/g之電容量。以上結果表明本研究可透過低成本且有效的球磨與鍛燒製程，將回收太陽能板之矽基材料結合石墨再製成Si/SiOx/C複合材料，透過交聯黏著劑與乙醇輔助方式協助性能的提升，於銅箔集電體提供高效能的充放電表現。;With technology and population growth, environmental and energy concerns are increasing. Among various renewable energy sources, solar energy has emerged as a leading green energy solution due to its ubiquity, sustainability, and low environmental impact. However, solar panels have a limited lifespan, and improper disposal can pose environmental hazards. Therefore, the recycling and reuse of solar panels have become crucial. Solar panels typically consist of solar cells, aluminum frames, and ethylene-vinyl acetate (EVA) components, with the solar cells predominantly composed of silicon (Si). Silicon, with its non-toxic nature, abundance, high theoretical capacity (4200 mAh/g), and low voltage platform (0.2-0.3 V), shows promise as a negative electrode material for lithium-ion batteries. However, silicon undergoes significant volume expansion/contraction during charging and discharging, leading to rapid capacity degradation. To address this issue, this study employed an economical and efficient ball milling and calcination process to convert recycled solar panel powder into negative electrode material. By adjusting the calcinating temperature to observe the residual EVA content and optimizing the sequence of ball milling and calcination, Si/SiOx material was prepared and combined with carbon paper current collector for application in lithium batteries. The optimal parameters were defined as calcinating at 500°C followed by ball milling at 300 rpm, resulting in a capacity of 1170 mAh/g after 100 cycles. Considering the demand for commercial negative electrode materials, in this study, silicon was combined with graphite to prepare Si/SiOx/C composite material. The results showed that a Si/C composite ratio of 1:0.6, combined with a crosslinking binder, resulted in a capacity of 488 mAh/g. To further enhance the performance, different ratios of ethanol were added as a solvent during slurry mixing to assist in the dispersion of Si particles and prevent aggregation. The results indicated that a water:ethanol ratio of 4:2 exhibited the best electrochemical performance, with a capacity of 748 mAh/g after 100 cycles. These results demonstrate that this study successfully utilizing recycled solar panels and transformed them into Si/SiOx/C composite material using a low-cost and efficient ball milling and annealing process. The performance was further improved through the use of a crosslinking binder and ethanol-assisted dispersion, providing high-performance charge-discharge behavior on copper foil current collectors. |
