【作者】 罗倩；

【导师】 廖小珍；

【作者基本信息】 上海交通大学 ， 化学工程， 2013， 硕士

【摘要】 对锂离子电池来讲，首次充放电过程中形成的负极SEI膜，有效地阻止了溶剂与活性材料的副反应，防止了溶剂分子的共嵌入，SEI膜性能的优劣直接影响到电池的循环性能、使用寿命、自放电及安全等性能。为了研究SEI膜的形成机理，探索SEI膜的影响因素，改善SEI膜的性能，本文以方型铝壳锂离子电池作为研究对象，针对化成条件进行DOE实验设计，采用恒流-恒压充放电、交流阻抗图谱等电化学测试技术对电池的循环性能、电极阻抗、极化电位等电化学性能进行了分析，并综合应用红外光谱技术、热重技术等对SEI膜的组成、热稳定性等性能进行研究。采用多种技术建立了综合评定SEI膜性能优劣的方法，通过对温度、电流和荷电态等化成条件进行DOE实验，获得不同性能的SEI膜，并对其进行综合评估。结果表明，化成过程中，采用0.05C的化成电流，温度为30℃，充电至30%荷电态下封口，上述化成条件下形成的SEI膜综合性能最优。更多还原

【Abstract】 Solid Electrolyte interface (SEI) was formed during the first cycle inLithium ion batteries. SEI played a important role in preventing the sidereactions between solvents and active material, and SEI also could restrainthe intercalation of solvent. So the quality of SEI film was one of the mostimportant factors for the cycle performance, discharge performance andsafety in lithium ion batteries.In order to study the formation mechanism of SEI film, factorsaffecting SEI film, and improvement of SEI film, the paper employedprismatic lithium-ion battery to determine the quality of SEI film based onDOE experiments of formation conditions. And electrochemicalperformance, including cyclic performance, impedance and polarizationpotential and other electrochemical properties were determined by CC-CVcharging and discharging, electrochemical impedance spectroscopytechniques, and so on. The composition and thermal stability of SEI filmwere analyzed by FTIR and DSC.To obtain different properties of SEI film, the paper designed DOEwith temperature, formation current and state of charge during theformation process. And we assessed the different properties of SEI film byusing a variety of techniques to establish a useful comprehensiveassessment method. The results show that, the formation conditions with0.05C current, charging to30%SOC at30℃, formed the best overallperformance of SEI film.更多还原