CAREER: Nano Electro-chemo-mechanics and Interfacial Stability in All-solid-state Lithium Battery

该学院早期职业发展（CAREER）资助将专注于了解全固态锂电池的基本反应机制，以确定故障的根本原因。全固态电池是继锂离子电池之后的下一代储能技术之一。它使用固体电解质，消除了易燃液体电解质的使用，预计将提高安全性和能量密度。然而，电解质的固体性质导致几个问题，例如缓慢的离子电导和机械断裂，导致装置的过早失效，特别是在发生化学反应和机械变形之间的复杂相互作用的电化学界面处。在这项研究中获得的基本见解可以战略性地用于设计固体电解质组合物和界面结构，以显着改善离子传导和机械稳定性，从而提高性能和循环寿命。它将有助于开发超越当前锂离子电池技术的先进储能设备，从而在该国和整个世界实现更可持续的社会和经济。该研究还将纳入教育和推广计划，以培训本科生/研究生，并吸引K-12学生到STEM领域。此外，该项目还与一家国际汽车公司组织了一项交流计划，为该行业的发展做出贡献，并培养具有工业和学术经验的下一代科学家/工程师。该项目旨在发现全固态锂电池在电化学界面失效的基础科学和单元过程。为了实现这一目标，将采用PI开发的原位透射电子显微镜技术。它能够精确评估原子和纳米尺度电化学反应过程中界面处的应变/应力演变与微观结构/化学变化之间的相互作用。该方法被系统地纳入研究中，以解决理解全固态锂电池故障的重要问题：1）在充电/放电过程中电解质/电极的微观结构如何变化？2)锂金属是如何穿透固体电解质的？以及3）是什么导致固体电解质破裂？原子模拟将进行构建一个理论框架的反应动力学和界面处的机械性能。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This Faculty Early Career Development (CAREER) grant will focus on understanding the fundamental reaction mechanisms in all-solid-state lithium batteries to identify the root causes of the failures. All-solid-state battery is one of the promising candidates as the next generation energy storage technology beyond Li-ion batteries. It uses solid electrolytes eliminating the use of the flammable liquid electrolyte and is expected to improve safety as well as the energy density. However, the solid nature of the electrolyte causes several issues such as slow ionic conductance and mechanical fractures leading to the premature failure of the device, in particular at the electrochemical interfaces where complex interactions between chemical reactions and mechanical deformations take place. The fundamental insights obtained in this study can be strategically utilized to design the solid electrolyte composition and the interfacial structure to significantly improve the ionic conduction and the mechanical stability for enhancing the performance and the cycle lifetime. It will contribute to develop advanced energy storage devices beyond current Li-ion battery technologies leading to a more sustainable society and economy in the country and the world overall. The research will also incorporate educational and outreach programs to train undergraduate/graduate students and attract K-12 students to STEM fields. In addition, the project organizes an exchange program with an international automobile company contributing to the development of the industry and produce next generation scientists/engineers who have both industrial and academic experience. This project aims to discover the underlying science and the unit processes of the failures in all-solid-state lithium batteries at the electrochemical interfaces. To achieve the goal, an in-situ transmission electron microscopy technique developed by the PI will be employed. It enables precise evaluation of the interplay between the strain/stress evolutions and the changes in the microstructure/chemistry at the interface during electrochemical reactions in atomic- and nano-scales. This method is systematically incorporated in the research to address the important questions for understanding failures in all-solid-state lithium batteries: 1) How does the microstructure of the electrolyte/electrode change during charging/discharging? 2) How does the lithium metal penetrate through the solid electrolyte? and 3) What causes the solid electrolyte to fracture? Atomistic simulations will be performed to construct a theoretical framework on the reaction kinetics and the mechanical properties at the interfaces. This, in combination with the experimental observations and measurements, further promotes the understanding of the reaction/degradation mechanisms.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.