Surface Modification of Lithium Battery Anodes with Multi-Functional Block Copolymers

多功能嵌段共聚物对锂电池负极的表面改性

• 批准号: 448754737
• 负责人: Professor Dr. Peter Müller-Buschbaum
• 金额: --
• 依托单位: National Natural Science Foundation of China
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/448754737?language=en
• 关键词: Surface; Modification; Lithium; Battery; Anodes

Lithium metal anode is regarded as one of the most promising next generation anode materials due to its exceptional capacity and lowest electrochemical potential. Nevertheless, formation and excessive growth of lithium dendrites cause series of adverse consequences. It can penetrate the separator to cause serious safety risks and induce formation of dead lithium to harm the coulombic efficiency. Drastic volume changes tend to destroy the solid electrolyte interface layer to deteriorate cyclic stability. These drawbacks seriously hinder practical applications of the lithium metal battery. It is proposed to use multi-functional PDMS based block copolymers and their organic/inorganic nanohybrids to modify the surface of the lithium metal anodes. The PDMS based block copolymers are featured with multiple advantages such as good elastomeric property, excellent lithium affinity, outstanding chemical inertness, capable of structure modification, and good solution processing capability. They can also form nanoscale structures on the lithium metal surface via a microphase separation process. The structure and property of the lithium metal interface is modified, where the formation and growth of lithium dendrites are suppressed, and structure stability of the solid electrolyte interface layer is enhanced. With this strategy, the electrochemical performance of the lithium metal anode is effectively improved. Through this joint project, the surface modification and device performance studies are combined with advanced ex situ and in situ scattering techniques (x-ray and neutron). The methods to perform reliable surface modification of the lithium metal anodes with the multi-functional block copolymers will be established. A good control over the structure and property of the surface modified lithium metal anode interface will be achieved. The structure-performance correlation of the surface modified lithium metal anode will be unveiled, and the mechanism will be understood. The implementation of the proposal will build solid scientific ground for practical application of the lithium metal batteries.

锂金属阳极以其优异的容量和较低的电化学电位被认为是最有前途的新一代阳极材料之一。然而，锂枝晶的形成和过度生长会导致一系列不良后果。它能穿透分离器造成严重的安全隐患，诱发死锂的形成，损害库仑效率。剧烈的体积变化往往会破坏固体电解质界面层，从而降低循环稳定性。这些缺陷严重阻碍了锂金属电池的实际应用。提出了利用多功能聚甲基丙烯酸酯嵌段共聚物及其有机/无机纳米杂化物修饰锂金属阳极表面的方法。PDMS基嵌段共聚物具有良好的弹性体性能、优异的锂亲和性、优异的化学惰性、良好的结构改性能力和良好的溶液处理能力等优点。它们还可以通过微相分离过程在锂金属表面形成纳米级结构。改变了锂金属界面的结构和性能，抑制了锂枝晶的形成和生长，增强了固体电解质界面层的结构稳定性。该策略有效地提高了锂金属阳极的电化学性能。通过这个联合项目，表面改性和器件性能研究与先进的非原位和原位散射技术（x射线和中子）相结合。建立了用多功能嵌段共聚物对锂金属阳极进行可靠表面改性的方法。可以很好地控制表面改性锂金属阳极界面的结构和性能。揭示表面改性锂金属阳极的结构-性能关系，了解其机理。该提案的实施将为锂金属电池的实际应用奠定坚实的科学基础。