本研究透過使用原位聚合法，導入兩種含硼基團單體分子(B系列與XB系列)進入PEG型的高分子系統中，以製備擬固態電解質薄膜。首先利用傅立葉紅外線光譜儀證實導入的單體都以聚合完成，可進行後續的實驗測試。接著透過壓縮測試了解此電解質系統都擁有不錯的機械強度，能承受至0.4 MPa的應力而不會有破碎的情形產生。而在導離子度與鋰離子遷移數的分析中發現導入含硼基團的樣品確實能提升其數值，其中B系列的最佳組成在60 oC的溫度下有著1.98 × 10-3 S/cm的導離子度，並且有著0.426的鋰遷數值，XB系列樣品則是有1.09 × 10-3 S/cm的導離子度，並有著0.347的鋰遷移數。此兩個樣品的測試數值都高過於對照組樣品(B0)，因此後續也選用其二個系列中的最佳組成作為電池應用效能的測試樣品。在充放電循環測試中，B系列樣品在0.1 C的充放電速率有著155.3 mAh/g的放電電容量，到了高速率的1 C也仍有151.9 mAh/g的電容量，在XB系列則分別為155.7 mAh/g和122.3 mAh/g。而在長效循環的部分，B系列樣品經過250圈後仍有93.6 %的電容維持率，XB系列樣品也可以維持90 %以上的電容維持率至138圈，顯示其不錯的長效循環壽命。接著進一步進行交流阻抗的測試，以了解電池內部SEI層的生成及阻抗變化的大小，在對照組的測試中發現其阻抗隨著循環的進行而快速增加，而B系列和XB系列樣品的阻抗值相對而言則微幅上升，能夠形成較為薄且致密的SEI層，有效抑制鋰支晶的生成。最後由SEM觀察在100圈循環後各樣品鋰金屬表面的結構，B系列相較於對照組與XB系列有著平坦且均勻的結構，而對照組與XB系列則有發現類似於鋰支晶的結構，此部分的結果也與其對應的循環電容量圖相對應。由上述可歸納出本研究導入含硼基團的高分子電解質具有不錯的電化學特性，可用於提升鋰電池的效能表現。

Using solid polymeric electrolytes to assemble lithium meatal batteries(LMBs) is a promising strategy to get high-safety batteries. However, limited ionic conductivity, low lithium-ion transference numbers and poor interfacial stability are challenging characteristics that hinder the practical application of solid-state LMBs. In order to settle these problems, we introduce two series of boron moiety-containing polymer electrolytes, which were based on poly(ethylene glycol) diacrylate (PEGDA), allylboronic acid pinacol ester(AAPE) and tricoordinate borate cross-linker (TBC) with an oligomeric plasiticizer (PEDGME) via in-situ thermal polymerization on lithium metal. Electrolytes prepared from AAPE and TBC are abbreviated as B series and XB series, respectively. For electrochemical property, B series exhibited an ionic conductivity of 1.98 mS cm−1 at 60 °C, while XB series presented 1.09 mS cm−1 at 60 oC. The value of transference numbers for B series electrolytes is 0.43, which is slightly higher than the value of 0.35 for XB series electrolytes, showing that contain larger content of boron moiety will have larger transference number. For the battery performance, LiFePO4 cells assembled with B series electrolytes demonstrate outstanding rate capacity(151.9 mA h g-1 at 1C) and long-term cycling performance (93.7% capacity retention after 250 cycles). The cells assembled with XB series electrolytes also can deliver a great discharge capacity (122.3 mA h g-1 at 1C) and cycle performance (89.3% capacity retention after 144 cycles). As the result, the LMB cell prepared using the polymer electrolytes with boron moiety showed an excellent
cycle performance.

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