Solid glass electrolytes for Li-metal batteries

锂金属电池用固体玻璃电解质

• 批准号: 2599358
• 金额: --
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2599358
• 关键词: Solid; glass; electrolytes; Li; metal

The conventional Li-ion battery chemistry is approaching its physicochemical limit. High energy active materials need to be implemented to develop the high energy density, low-cost and safe batteries that can meet the requirements of the expanding electric vehicle market and empower novel applications such as electric flight. This could be achieved by replacing the organic liquid electrolyte with a solid electrolyte, enabling the safe implementation of Li-metal anodes.Solid glassy electrolytes have attracted much attention mainly due to their advantages over the crystalline counterparts, namely isotropic ionic conduction, absence of grain-boundaries and associated resistance and ease of fabrication into films. In addition, the ion conductivity of amorphous glasses is generally higher than that of their crystalline counterparts because of their open structure.Li-ion conducting glasses can be divided into two main categories: oxides and sulfides. Oxide glassy electrolytes are chemically stable and display a wide electrochemical stability window nevertheless their lithium-ion conductivity at room temperature is too low to be practical for high energy batteries (10E-6-10E-8 S/cm). Sulphide glasses, on the other hand, display high lithium-ion conductivities at room temperature (10E-3 - 10E-5 S/cm) thanks to the high polarisability of sulphide ions. Unfortunately, they can react with ambient moisture and generate the toxic hydrogen sulphide gas.Oxy-halide glassy electrolytes derived from anti-perovskite lithium hydroxy halides (Li2OHX, X=Cl, Br) have recently shown potential in bridging the gap between the electrochemical stability of oxides and ionic conductivity of sulphides.In this project the student will explore the synthesis and characterization (structural, physico-chemical and electrochemical) of oxy-halide solid glassy electrolytes, compatible with the lithium metal anode. The effect of composition and morphology on mechanical properties and ion transport will be investigated in detail. The mechanism of ion conduction will be explored both experimentally (solid-state NMR and electrochemical impedance spectroscopy) and by first-principle calculations. The lithium metal-solid electrolyte interphase will be probed by XPS (ex-situ, in-situ and operando), AFM and advanced electron microscopy techniques.This project falls within the EPSRC Energy research area. The aim of this theme is for the UK to meet its environmental and energy targets.The project is partially sponsored (DTP-CASE) and will be carried out in collaboration with Morgan Advanced Materials.

传统的锂离子电池化学正在接近其物理化学极限。需要采用高能活性材料来开发高能量密度、低成本和安全的电池，以满足不断扩大的电动汽车市场的需求，并为电动飞行等新应用提供动力。这可以通过用固体电解质代替有机液体电解质来实现，从而使Li-金属阳极的安全实施成为可能。固体玻璃态电解质吸引了很多关注，主要是由于它们相对于结晶对应物的优点，即各向同性离子传导、不存在晶界和相关电阻以及易于制造成膜。此外，由于非晶态玻璃的开放结构，其离子电导率通常高于晶态玻璃。锂离子导电玻璃可分为两大类：氧化物和硫化物。氧化物玻璃态电解质是化学稳定的，并且显示出宽的电化学稳定性窗口，然而它们在室温下的锂离子电导率太低，对于高能电池（10 E-6- 10 E-8 S/cm）是不实用的。另一方面，由于硫离子的高极化率，硫化物玻璃在室温下显示出高锂离子电导率（10 E-3 - 10 E-5 S/cm）。不幸的是，它们会与环境中的水分发生反应，产生有毒的硫化氢气体。反钙钛矿型锂羟基卤化物衍生的卤氧化物玻璃态电解质（Li 2 OHX，X=Cl，Br）最近在弥合氧化物的电化学稳定性和硫化物的离子导电性之间的差距方面显示出了潜力。在这个项目中，学生将探索合成和表征本发明涉及与锂金属阳极相容的卤氧化物固体玻璃状电解质的结构、物理化学和电化学性质。将详细研究组成和形态对机械性能和离子传输的影响。离子传导的机制将探索实验（固态核磁共振和电化学阻抗谱）和第一原理计算。锂金属-固体电解质界面将通过XPS（非原位，原位和操作），AFM和先进的电子显微镜技术进行探测。该项目属于EPSRC能源研究领域的福尔斯。该主题的目的是为英国实现其环境和能源目标。该项目是部分赞助（DTP-CASE），并将与摩根先进材料合作进行。