隔離膜是鋰離子電池中的重要組成之一，目前的商用隔離膜為聚烯烴材料，但是在高溫下會融化收縮，具有安全風險，加上此材料為疏水性，與電解液的親和力較差，在電池性能與安全性方面需要進行改善。 本研究使用浸塗法讓氧化鋁包覆於聚乙烯(PE)隔離膜的表面，增加熱穩定性與親水性。再藉由AM 及 BM 共聚形成枝狀寡聚物oAB作為具有阻燃性質的黏著劑，來改善陶瓷塗層的結構，於陶瓷材料的高熱穩定性基礎上，進一步提高阻燃效果與電池性能。 研究中則使用熱聚合方法和光聚合方法，製備出不同結構的oAB產物，並以不同比例作陶瓷塗層隔離膜黏著劑，探討應用在鋰離子電池的影響。在燃燒測試結果中，兩種oAB都可以延長燃燒時間，達到阻燃效果。在電池性能上兩種oAB呈現不同的表現。熱聚合oAB做為良好的黏著劑，可以改善陶瓷塗層結構，同時擔任添加劑的角色，形成穩定的固體電解質介面，達到更好的循環壽命表現：在0.5C速率500圈充放電循環的條件下，與不添加黏著劑的氧化鋁塗層隔離膜相比，電容保持率從62.7%提升到79.6%。光聚合oAB則是具有比熱聚合oAB更加緻密的結構，能改善寡聚物阻擋離子傳輸通道的情形，提升電容表現：在0.5C的充放電速率下，與添加熱聚合oAB的氧化鋁塗層隔離膜相比，第一圈循環的電容值從80.5 mAh/g提升到96.6 mAh/g。 ;A separator plays an important role in ensuring the safety in lithium-ion batteries. However, commercial separators are mainly based on polyolefin membranes, which possess serious safety risks, such as their thermal stabilities. In addition, this material is hydrophobic and has poor affinity with electrolyte. In this study, we use aluminum oxide to coat on the surface of the polyethylene(PE) separator to increase hydrophilicity and the dimensional stability at high temperatures by dip-coating method. The binder is based on a hyberbranched polymer oAB, which is composed of AM copolymerized with BM. The main purpose is to improve the flame-retardant effect and the battery performance on the basis of the high thermal stability of the ceramic material. We use different methods to prepare oAB. In the combustion test results, both types of oAB can achieve the flame-retardant effect. However, there are different performances in electrochemical performance. Thermal polymerized oAB (termed as oAB-T) can act as both binder and additive, which exhibits an improved ceramic structure and participates in the formation reaction of the solid electrolyte interface to achieve better cycle performance. The capacitance retention of oAB-T 0% ceramic separator and oAB-T 2.4% ceramic separator are respectively 62.7% and 79.6% at 0.5C after 500 cycles. Photopolymerizable oAB (termed as oAB-P) has a denser structure, which occupies a smaller volume between the ceramic particle, making it easier for lithium ions to transport in the battery. The battery has the best capacitance performance in the early stage of use. With the addition of oAB-T 2.4% and oAB-P 2.2%, the battery capacity of the first cycle increased from 80.5 (mAh/g) to 96.6 (mAh/g) at 0.5C.
