Design of Advanced All Solid State Rechargeable Batteries Conducting Multivalent Cations

以Mg^<2+>或Al^<3+>等多价矿物离子为载流子的固体电解质有望应用于新型固态电池。本研究成功制备了导镁凝胶聚合物电解质，并对其性能进行了研究。将含多价阳离子镁盐的离子液体溶于两种不同阳离子的离子液体中，制备了聚合物复合电解质。研究了溶液的离子电导率和热性能等基本性质。将离子液体溶液与具有二维极性基团结构的聚合物基体结合，制备了固体复合电解质。研究了复合电解质的热性能和离子电导率。优化了离子液体溶液和聚合物基体的组成。镁离子在复合电解质中的迁移率分析为了估计Mg^<2+>在制备的复合电解质中的迁移率，进行了直流极化试验并监测了电流响应。发现Mg^<2+>在聚合物复合材料中有迁移。电极材料的优化与电池性能的评价选择了Mg金属、Mg合金和Mg掺杂V_2O_5作为复合电解质的最佳负极材料。恒流充放电试验结果表明，聚合物复合电解质与电极之间的界面有必要进行修饰。

A solid electrolyte where multivalent mineral ion such as Mg^<2+> or Al^<3+> acts as charge carrier is expected to be applied in a novel solid-state battery. In the present study, Mg-conductive gel polymer electrolytes have been successfully prepared and the following properties have been investigated.1.The preparation of a polymer composite electrolyte with ionic liquid containing multivalent cationA magnesium salt was dissolved in two kinds of ionic liquids having different cation. The basic properties such as ionic conductivity and thermal property of the solutions were investigated. Solid composite electrolytes were prepared by combining the ionic liquid solutions and polymer matrix having a 2-D structure with polar groups. The thermal property and ionic conductivity of the composite electrolytes were investigated. The composition of ionic liquid solutions and polymer matrix was optimized.2.The analysis of the mobility of magnesium ion in the composite electrolytesIn order to estimate the mobility of Mg^<2+> in the prepared composite electrolyte, a direct current polarization test was carried out and the current response was monitored. It is found that Mg^<2+> migrates in the polymer composite.3.The optimization of electrode material and the evaluation of the battery cellThe optimum negative electrode material toward the composite electrolyte was selected from Mg metal, Mg alloy and Mg-doped V_2O_5 for a small-size battery cell. The result of constant-current charge-discharge test indicated that the interface between polymer composite electrolyte and electrode is necessary to be modified.