2020年武漢病毒無預警肆孽全球，衝擊全球產業的同時卻也加速了特定科技產業的新陳代謝。其中，鋰離子電池電動車就是一個鮮明的例子，在傳統車市一片黯淡中異軍突起，確立了不可逆的產業轉變。當電動車變成產業必然，鋰電池產業也將迎來擘劃已久的高速成長。這樣的改變讓原本就已是高度關注的鋰電池材料研究匯聚更多目光，因此產業對新材料的期待更為迫切的情形下，研究與產業的銜接也就顯得格外重要。
在電池材料的研究方面，大多數的學者都聚焦在正極、負材以及電解液添加劑的相關研究，期望藉此提升整體電池效能。只有少數的研究團隊將心力放在隔離膜材料的探究，即使隔離膜材料對於電池的能量密度、功率密度乃至於電池安全性都有至關重要的影響。過去的數年，鋰電池不段追求能量密度的提升，可以預期市場/學者不會滿足於現況，電池能量仍會快速成長。在效能提升的同時，隨之而來的是日漸升高的安全性風險，但肩負安全性的鋰電池隔離膜材料卻仍使用傳統的PP以及HDPE隔離膜。若隔離膜材料沒有隨著電池效能而同步提升，預期鋰電池的發展將因傳統隔離膜安全性不足而受限。因此在這個時刻，持續發展更高功能並兼具安全性的鋰電池隔離膜材料是值得投入的研究領域。
如前所述，隨著二次電池市場擴展到電動汽車，傳統的聚烯烴隔膜無法滿足鋰離子電池（LIB）對高功率密度、高能量密度和高安全性的日益增長的要求。然而，降低離子傳輸阻力、提高熱穩定性和改善聚合物基隔膜的機械性能仍然是一個巨大的挑戰。本研究以基礎乾式隔離膜研究出發，詳細討論聚丙烯材料之結晶形貌以及結晶順向度，同時建立一系列微結構量測方法，藉以量化結晶順向度，並由此討論結晶對延伸造孔過程的影響。
基於聚丙烯材料研究的基礎，本研究設計並展示了一種由聚乙烯/奈米氧化鋁複合材料所製備的有機無機複合隔離膜。在此系統之中，奈米結構氧化鋁粒子 (NPs) 的柔性多臂結構極大地促進了聚合物加工過程中高密度聚乙烯 (HDPE) 的順向性，顯著優化了隔離膜形成過程中的造孔程序。所得複合隔膜的孔隙率、孔徑分佈、熱尺寸穩定性和機械強度得到顯著改善，從而具有長循環壽命和高倍率性能。此研究不僅展示了一種新的高功能鋰電池隔離膜，更重要的是開創了以奈米無機粉體控制聚烯烴材料取向和孔隙優化設計的新方法，並以接近量產的方法進行驗證，極具產業價值。在最後，本研究所提出的造孔優化機制也在聚甲基異戊烯(Polymethylpentene, PMP)的複合材料系統再次得到驗證，所製備的孔隙薄膜也展現出超越市售鋰電池隔離膜優異的高溫穩定，從而提高了鋰電池使用的安全性。

In 2020, the Covid-19 ravaged the world without warning. While impacting global industries, it also accelerates the change of specific industries. Lithium-ion battery electric vehicles is a best example. It has rocketed amid the bleakness of the traditional auto market and established an irreversible industrial transformation. When electric vehicles become an industry new standard, the lithium battery industry will also take the long-planned rapid growth. This change has brought more attention to the research of lithium battery materials, which is already highly concerned. Therefore, the connection between research and industry becomes particularly important when the industry's expectations for new materials become more urgent.
In the research of battery materials, most researcher have focused on positive, negative materials and electrolyte additives to improve the overall battery performance. Only a few research teams focus on the battery separators, even though it strongly effects the energy density, power density and even the safety of the battery. In the past few years, the energy density of lithium-ion batteries has been increased. The safety risks are increasing day by day during this energy increasing process. However, the conventional PP and HDPE base separators still be used in new battery system. If the separators do not improve simultaneously with battery performance, we can expect that the development of lithium batteries will be limited due to the lack of safety of traditional separators. Therefore, at this moment, the keep development of separator materials with higher functions and safety is a research field worth investing in.
As we mentioned earlier, as the secondary battery market extent to electric vehicles, traditional polyolefin separators cannot meet the increasing demands of lithium-ion batteries (LIB) for high power density, high energy density, and high safety. However, reducing ion transport resistance, improving thermal stability, and improving the mechanical properties of polymer-based membranes still a huge challenge. This research focus on separators material use in dry process, discusses the polymer crystal morphology of polypropylene materials in detail, and establishes a series of microstructure measurement methods to quantify the crystal orientation and clear the evolution of crystal during the stretching process.
Based on the foundation of polypropylene materials, this research further designed and demonstrated an organic-inorganic composite separators made by polyethylene/nano-alumina composite material. In this system, the flexible multi-arm structure alumina nanoparticles (NPs) greatly promote the crystal orientation of high-density polyethylene (HDPE) during polymer processing, and significantly improve the properties of the porous membrane. The porosity, pore size distribution, thermal dimensional stability and mechanical strength of the obtained composite porous film are significantly improved, thereby having long cycle life and high rate in battery performance. This research not only demonstrated a new high-functional lithium battery separator but create a new field of separators modification with nano-inorganic powder, and verified it with a productive method which close to mass production. Great industrial value. In the end, the pore-forming optimization mechanism has also been verified again in another composite material system as polymethylpentene/nano-alumina, and the prepared porous film also shows excellent performance beyond the commercially available separators. Such high temperature stability can improves the safety of lithium batteries.

第一章、緒論與研究動機·····························1
第二章 文獻回顧與原理······························5
2.1 鋰離子電池發展 ·······························5
2.2商用鋰電池隔離膜材料與市場趨勢···················11
2.3鋰電池隔離膜的種類. ···························22
2.4 高分子薄膜押出技術. ··························34
第三章 實驗方法. ································36
3.1研究流程 ····································36
3.2原料 ·······································37
3.3複合材料混摻方法 ·····························38
3.4 薄膜製作方法 ································38
3.5 儀器設備原理·································41
第四章 結果與討論 ································47
4.1聚丙烯延伸造孔製程中的微結構變化··················48
4.2製程參數對單層聚丙烯孔隙膜 ······················61
4.3 HDPE複合材料系統 ·····························67
4.4 PMP複合材料系統·······························82
第五章 結論與未來展望 ·····························96
第六章 參考文獻·································· 98

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