锂离子二次电池具有能量密度高、输出电压高、自放电小、无记忆效应等优点，然而安全性问题了阻碍锂离子电池在动力电池等领域的应用。为此，本论文开展了聚醚醚酮材料基耐热型隔膜与固体电解质的研究，博士期间主要成果如下：1）聚醚醚酮（PEEK）材料具有高耐热性、抗热缩性、优异物理化学稳定性等特点，具有作为锂离子电池隔膜材料的潜力。然而其不溶难融的特点导致其难以被加工为多孔薄膜。本论文首先提出一种“曲线”加工法：先在PEEK高分子上化学修饰侧链，赋予其可溶性；加工成膜后，褪化掉修饰侧链，复原PEEK高分子稳定性。所制备隔膜150 ℃无热缩，250 ℃面积热缩率仅18.3%， 282 ℃不熔化、降解。将所制备隔膜用于锂离子电池，倍率放电容量最高提升36.8%。2）改进PEEK高分子修饰工艺，使其绿色环保。设计和制备了交联醚修饰PEEK无纺布隔膜。所制备隔膜具有更优异的抗热性能和润湿性能。180 ℃无热缩，260 ℃面积热缩率仅-10%，热降解温度达476 ℃，电解液对隔膜接触角降为0 度。所制备隔膜用于锂离子电池，倍率放电容量最高提升42.5%。3）设计和制备了改性PEEK/聚甲基丙烯酸甲酯/改性PEEK三层隔膜，赋予隔膜自闭孔特性，可在温度过高的情况下阻断锂离子穿梭，停止电池反应和反应放热，阻断热失控过程。该隔膜具有很宽的阻断窗口（100 — 270 ℃）和优异的性能（对电解液完全润湿、150 ℃无热缩、240 ℃面积热缩率小于-13.37%、热分解温度350 ℃、电化学稳定性 > 5.65 V等）。4）使用固体电解液替代易燃易爆的液体电解质，进一步提升锂离子电池安全性。针对固体电解质离子传导率过低的问题，通过咪唑鎓阳离子改性POSS，调控聚合物电解质微相分离，构建点状离子传递通道，使固体电解质离子传导率提升3倍，离子传递活化能下降32.24%，为后面工作提供理论指导和工作灵感。5）针对点状通道离散、不连续的问题，构建了线状离子传递通道。设计[1-(三氟甲基磺酰亚胺锂)砜]-PEEK作为锂离子传导纳米导线，设计一种超支化的交联聚（甲基丙烯酸聚乙二醇酯）作为路易斯碱基团供体。利用高分子的自组装作用形成微相分离结构，构建连续、联通的高效锂离子传递通道。所制备的聚合物电解质在25 — 90 ℃，电导率可达0.17 — 1.01 mS cm-1，锂离子迁移数高达0.936 — 0.898，分解电压为5.19 — 4.52 V。与磷酸铁锂正极、锂片负极一起装配电池，可获优异的倍率性能和循环稳定性能。

Compared with the other secondary batteries, lithium ion battery possesses many distinguish features like high power density, high output voltage, low self-discharge etc. However, the concern on the safety of lithium ion battery greatly hampers its more widespread application duo to abundant fire disaters and explosions. This thesis focuses on solving this concern, and the devoted efforts are listed below：1）Poly (ether ether ketone) (PEEK) is a potential materials for lithium ion battery separator due to its natures like thermal resistance, anti-shrinkage property, excellent physical and chemical stabilities. But it is hard to process PEEK to porous membranes because of the insolubility in most of solvents and the high melting temperature of > 350 oC. This thesis presented an indirect technology to process PEEK. PEEK was firstly modified with chloromethyl group as pendent group by Blanc chloromethylation to disturb the polymer crystallization, endowing PEEK with solubility. Then the modified PEEK was fabricated to porous membrane. Finally, the chloromethyl group were replaced by hydroxymethyl group to recover the stabilities of PEEK based membrane. The obtained membrane (OHPEEK) showed no shrinkage at 150 oC, only -18.3% shrinkage at 250 oC, and high thermal stability (degradation temperature up to 282 °C). In addition, the rate performance of lithium ion battery was increased by up to 36.8% after equipping with the OHPEEK membrane.2）A green and eco-friendly modification process was exploited to achieve the modification of chloromethyl group at the PEEK polymer, and then presented a nonwoven membrane based on crosslinking ether groups. Compared with the OHPEEK membrane, the nonwoven membrane exhibited more excellent properties like no shrinkage at 180 oC, only -10.0% shrinkage at 260 oC, high degradation temperature of 476 °C and outstanding wettability (contact angle of 0 o). In addition, the rate performance of lithium ion battery was increased by up to 42.5% after equipping with the nonwoven membrane. 3）A modified PEEK/ polymethyl methacrylate/ modified PEEK tri-layer membrane was exploited to achieve the shutdown property of lithium ion battery. The robust modified PEEK outer layers were strong enough to support the tri-layer membrane, prevent the collapse. The polymethyl methacrylate possessing low melting point could melt at elevated temperature, which blocked the pores of tri-layer membrane, and avoided the transfer of lithium ion. By this way, the electrodes were completely divied at elevated temperature, and the electrode reactions can be terminated. This shutdown property can effectively avoid the thermal runaway of lithium battery, endowing the lithium ion battery with improved safety. The obtained tri-layer membrane had a broad shutdown temperature window of 100 - 270 ℃, no shrinkage at 150 oC, only -13.37% shrinkage at 240 oC, high degradation temperature of 350 °C and outstanding wettability (contact angle of 0 o). 4）The liquid electrolyte for lithium ion battery consist of lithium salt and combustible carbonic ester. In order to futher improve the safety of lithium ion battery, one approach is to replace the dangerous carbonic ester based liquid electrolyte by solid state polyelectrolyte. Low ionic conductivity is a bottleneck for the application of solid state polyelectrolyte. This thesis manipulated the microphase separation structure of solid state polyelectrolyte by incorporating densely-modified POSS, creating dot-like ionic pathways for high-speed lithium ion transfer. The ionic conductivity of the obtained solid state polyelectrolyte was increased by 3 times, and the activation energy of ionic transfer decreased by 32.24%. 5）Linear ionic pathways was created to further facilite the ionic transfer in polyelectrolyte by dispersing a well designed polymer, lithium sulfonyl(trifluoromethanesulfonyl)imide modified PEEK in a hyperbranched polymer, poly(polyethylene glycol methyl ether methacrylate). Compared with the dot-like pathways, the linear ionic pahways were continuous, interconnected and ordered. The obtained polyelectrolyte showed high ionic conductivity of 0.17 – 1.01 mS cm-1 at 25–90 ℃, high lithium transfer number of 0.936 – 0.898 and high electrochemical stability of 5.19 – 4.52 V. A hal-fcell using this polyelectrolyte exhibited discharge capacities (0.2C) of 121.7 and 152.7 mA h g-1 at 25 and 60 ℃, respectively.