In-situ Spectroscopic Investigations of High Energy Li-S Batteries Based on New Carbon Cathodes

基于新型碳阴极的高能锂硫电池的原位光谱研究

• 批准号: 273723695
• 负责人: Dr. Burkhard Beckhoff
• 金额: --
• 依托单位: Leibniz-Institut für Polymerforschung Dresden (IPF)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/273723695?language=en
• 关键词: situ; Spectroscopic; Investigations; Energy; Li

The successful design of Li-S batteries with high energy density has the challenging perspective to significantly improve existing battery technology and to boost the development of environmentally friendly automotive development. Li-S batteries could triple the energy density of existing Li-ion batteries combined with high reversibility of fast charging-discharging cycles and lifetime of thousands of cycles. Recently, based on novel approaches for battery design we have been able to develop Li-S test cells with relatively high energy density and stability over 50 cycles. There are, however still problems to be solved related to the insulating nature of active sulfur, polysulfide dissolution and redox shuttle phenomena, volume expansion, electrode passivation by sulfides etc. that limits the performance of Li-S batteries. In this project we will develop novel composite cathodes, protective membranes and new electrolytes which will allow improvement of the performance of Li-S batteries. Due to the complex nature of ongoing processes we believe that systematic and basic studies of charging and discharging processes are necessary. Therefore, we propose to use sophisticated characterisation techniques, i.e. near edge X-ray absorption fine structure (NEXAFS) spectroscopy, Raman spectroscopy and electron spin resonance, where chemical modifications at different locations inside the cell during charging and discharging may be followed in situ and radical formation is detected. Thus, elemental sulfur and in particular polysulfide distribution and kinetics will be determined, allowing specific optimisation of the cells. In our multidisciplinary consortium, development of new polymer-based porous cathode materials, formulation of advanced electrolytes and optimisation electrochemical performance at experimental and theoretical levels will be realised by the combined efforts of the three partners. Application aspects will be discussed in close contact with a leading battery producing company.

具有高能量密度的锂硫电池的成功设计具有挑战性，可以显著改善现有电池技术并促进环保汽车的发展。锂硫电池可以将现有锂离子电池的能量密度提高三倍，同时具有高可逆性的快速充放电循环和数千次循环的寿命。最近，基于电池设计的新方法，我们已经能够开发出具有相对高的能量密度和超过50次循环的稳定性的Li-S测试电池。然而，仍然存在与活性硫的绝缘性质、多硫化物溶解和氧化还原穿梭现象、体积膨胀、硫化物引起的电极钝化等有关的问题有待解决，这些问题限制了Li-S电池的性能。在该项目中，我们将开发新型复合阴极、保护膜和新电解质，以提高锂硫电池的性能。由于正在进行的过程的复杂性，我们认为，充电和放电过程的系统和基础研究是必要的。因此，我们建议使用复杂的表征技术，即近边缘X射线吸收精细结构（NEXAFS）光谱，拉曼光谱和电子自旋共振，其中在充电和放电过程中，在电池内部的不同位置的化学修饰可以在原位进行后续和自由基的形成进行检测。因此，将确定元素硫和特别是多硫化物的分布和动力学，从而允许电池的特定优化。在我们的多学科联盟中，新型聚合物基多孔阴极材料的开发，先进电解质的配制以及实验和理论水平上的电化学性能优化将通过三个合作伙伴的共同努力实现。应用方面将与领先的电池生产公司密切联系进行讨论。