鋰電池的應用已從小電力可攜式產品擴展到運輸工具及中大型儲能系統，其中，全固態電池(All Solid-State Batteries, ASSB)因其高安全性與高能量密度的特性，已不約而同地被規劃在世界上重要電化學儲能科技白皮書上，因此，全固態電池已是目前世界各國以及各大車廠極力開發的電動車元件。然而，目前全固態電池的性能仍無法與現今主流具液態電解質之鋰電池相比，在全固態電池眾多極待發展的課題中，降低電池阻抗為最關鍵的核心技術之一。本研究著重探討石榴石結構固態電解質，以鋰金屬為負極，在不同溫度及壓力條件下，組裝成對稱電池後分析其電化學阻抗，以及鋰的溶解和析出的行為。由化學阻抗之等效電路分析，我們嘗試去解構在不同的溫度及壓力條件對界面貼合度產生的影響。然而在本研究中，組裝溫度的提升以及增加組裝時的堆疊壓力與界面的阻抗降低程度不完全正相關，與預期結果不同。但是從這也可以側面證實LLZO與Li電極表面的乾淨程度對界面貼合度產生的影響，若表面沒有汙染物的產生或是殘留，那麼界面貼合度也會有所提升，達到降低界面阻抗的效果。

Lithium-ion batteries has been extensively applied ranging from portable electronic devices to transportation and medium to large scale energy storage. Among the existing technologies, all solid-state batteries (ASSBs) possess the merits of high safety and high energy density. Developing ASSB has been proposed in various important roadmap for electrochemical energy storage. Thus, major vehicle manufactures in the world have devoted to developing ASSBs as the key component in electric vehicles (EVs). However, the performance of current ASSBs is not competitive compared with the Li-ion batteries using conventional liquid electrolytes on the market. Among the emerging issues of ASSBs, lowering their internal impedance is the key one. In this research, we studied the effects of different assembly temperatures and stacking pressures on the interfacial resistance between Li anode and LLZO solid electrolyte. We measured the electrochemical impedance spectra and the constant direct current behavior. Hence, we tried to deconstruct the extent of intimate contact of the interface and the deposition and dissolution behavior of lithium. Despite that we didn’t prove that rising the assembly temperature and the stacking pressure always reduced the interfacial resistance, we did verify the importance of the surface conditioning. The better the preconditioning such as polish and heat treatment, the smaller the interfacial resistance. It was the contamination layer produced or remained at the interface that mattered.

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