高比能硫基复合材料的设计、电化学性能及界面特性研究

项目名称： 高比能硫基复合材料的设计、电化学性能及界面特性研究

项目编号： No.51202094

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 无机非金属材料学科

项目作者： 赖超

作者单位： 江苏师范大学

项目金额： 25万元

中文摘要： 锂/ 硫二次电池是最具发展潜力的新型高能化学电源体系之一。但是，硫正极材料存在的活性物质偏低和循环性能较差等缺点制约了锂/硫电池的快速发展。本课题以开发具有高能量密度和稳定循环性的锂/硫电池新体系为目标，拟开展以下研究工作: (1) 构建多孔钛酸盐填充封装的硫-大孔碳复合正极材料，其中以大孔碳负载硫，以多孔氧化物将溶解的多硫化物限定在孔道内，实现硫-碳复合正极材料高比容量和良好的循环稳定性的结合; (2) 引入数字全息术来研究锂/硫电池的固液界面特性，揭示充放电过程中硫-碳复合正极和电解液界面间的相互作用机制，研发出和硫-碳复合材料相匹配的有机电解液. (3) 在上述研究成果的基础上，制备多孔钛酸盐封装的硫-介孔碳微米管阵列复合正极材料，并结和匹配电解液,以开发出具有高能量密度和良好电化学性能的锂/硫电池新体系。

中文关键词： 锂硫电池；表面包覆；亲水性隔膜；电化学活性碳间层；数字全息技术

英文摘要： Lithium-sulfur ( Li-S )battery has been receiving more attention due to its high theoretical energy density of 2600Wh/kg. However, there are still some serious problems for sulfur cathode in organic electrolyte, including the lower utilization and poor cycle performance of sulfur active material, which become a big barrier for the research and development of lithium-sulfur battery. In order to develop a novel system of Li-S battery with high-energy density and stable cycle performance, this project focuses mainly on the following issues: (1) Fabrication of sulfur/macroporous carbon composite cathode encapsulated by porous titanate. For the design composite cathode, macroporous carbon is employed to load sulfur to ensure high-loading, and porous titanate to restrain the dissolution of polysulfides. Sulfur/macroporous carbon composite cathode encapsulated by porous titanate is expected to demonstrate a high specific capacity and stable cycling performance. (2) Introduction of Digital holographic interferometry in the secondary battery systems. Digital holographic interferometry is employed to study the interface reaction process between the composite cathode and electrolyte, and then clarify the electrochemical reaction mechanism of Li-S batteries. Under the guidance of mechanism, further research is to develop m

英文关键词： Lithium-sulfur batteries；Surface coating；Hydrophilic separator；Electroactive interlayer；Digital holographic interferometry