聚合物电解质是新一代锂离子电池所需要的重要材料.本文从分析聚丙烯腈(PAN)-增塑剂-LiClO4体系中各组份间的相互作用出发,用Raman光谱,红外(IR)光谱,X射线光电子能谱(XPS)及核磁共振(NMR)等谱学方法研究了聚合物电解质中各组份之间的相互关系和Li+离子在聚合物电解质中的输运机理.发现Li+离子既可与增塑剂分子中含有孤对电子的原子发生作用而形成缔合物,也可与PAN中C≡N基团上的N原子发生作用形成缔合物.增塑剂分子通过C=O或S=O基团与PAN的C≡N基团以偶极子的形式相互排斥.在与Li+离子相互作用形成缔合物时,聚合物分子与增塑剂分子间存在激烈的竞争.在凝胶态中的运动是聚合物电解质Li+离子的主要运动形式.提出了Li+离子在PAN为基的聚合物电解质中的一种可能传导机制.强调了增塑剂在聚合物电解质中的重要作用.
Raman, IR, X-ray photoelectron (XPS), and NMR spectra of components in polyacrylonitrilebased electrolytes have been studied. It is found that there are strong interactions among the components though different systems show different interaction characteristics. A concept of competition is proposed between the polymer matrix and the plasticizer on associating with the Li~+ ions. By analyzing the important functions of the plasticizer, a possible mechanism of the ions transport in the polymer electrolyte is suggested.
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