Development of Solid Electrolytes for Solid-State Lithium Batteries

背景：开发安全、高性价比、高能量密度的全固态锂电池可以实现可持续道路交通系统的梦想。主要有两个原因推动了对这类系统的研究。首先，最先进的液态电解液锂离子电池(LIB)在恶劣条件下的易燃性和不稳定性带来了安全和可靠性问题。其次，目前不可能使用锂金属作为负极，这限制了电池的能量密度。在这方面，固体电解质(Ses)显示出几个优点：Ses抑制Li树枝晶的形成，不可燃，并使全固态电池(ASSB)具有高功率密度。尽管SSB具有明显的优势，但目前由于稳定和高性能的Li+运输SE的有限，SSB的使用被推迟了。目标：该项目的总体目标是开发新型先进的、具有高界面稳定性和电化学稳定性的锂离子导电固体电解液，用于下一代全固态锂电池，并开发制造全固态锂电池的先进概念。选定的Li+输运SES将进行适当的修饰，以获得更高的界面稳定性和降低晶界电阻。在第二种方法中，将筛选出具有高稳定性的新型含锂氟化物，并将开发用于增强固态电池中Li+导电性和集成度的选定系统。

Context: The development of safe and cost-effective high energy density all-solid-state lithium batteries can realize the dream of the sustainable road transport system. Mainly two reasons are driving research on such systems. First, the state-of-the-art lithium-ion batteries (LIBs) with liquid electrolytes (LEs) pose safety and reliability issues due to their flammability and instability under harsh conditions. Second, the use of Li metal as an anode is not possible at the moment which limits the energy density of the batteries. In this regard, solid electrolytes (SEs) exhibit several advantages: SEs suppress Li dendrite formation, non-flammable, and enable high power density for all-solid-state batteries (ASSBs). Despite their obvious advantages, the use of SSBs is currently delayed by the limited availability of stable and high performant Li+ transporting SEs. Objectives: The overall objective of this project is to develop new and advanced Li+ conducting solid electrolytes with high interfacial and electrochemical stability for its employment in future generation all-solid-state lithium batteries and to develop advanced concepts to build all-solid-state lithium batteries.Approach: The project will focus on key challenges via two routes. Selected Li+ transporting SEs will be modified suitably to attain increased interfacial stability and to reduce the grain boundary resistance. In a second approach, novel Li-containing fluoride compounds with high stability will be screened, and selected systems will be developed for enhanced Li+ conductivity and integration in solid-state battery cells.