Mechanics for Energy Sustainability: 
from fatigue of 2D materials to dendrites in solid-state batteries

Dr. Teng Cui

Stanford University

Achieving energy sustainability requires a concerted effort in developing both energy-efficient materials and reliable energy-storage/conversion technologies. Two-dimensional (2D) materials hold great promise as energy-efficient electronic materials and as nanofillers for energy-efficient structural nanocomposites. Among various energy-storage technologies, solid-state batteries (SSB) are attractive due to higher energy density and safer, non-flammable solid electrolytes compared with conventional lithium-ion batteries. However, both 2D materials and SSB are constantly exposed to long-term static and dynamic stresses due to both mechanical loading and complex multiphysics coupling, posing critical challenges to their mechanical reliability.

The first part of my talk will focus on the fracture and fatigue behavior of freestanding 2D materials (e.g., graphene and MoS₂) and their interfaces. Using advanced atomic force microscopy and in-situ techniques, I will show the unconventional fatigue behavior and failure mechanisms at the atomic scale. Practical strategies to improve their mechanical reliability are also proposed. The second part will discuss the lithium dendrite issues in SSB and investigate the coupled electro-chemo-mechanical effect in the failure of a ceramic solid electrolyte. Through in-situ SEM experiments, the critical role of stress in regulating the failure of SSB during fast charging is revealed.

Dr. Cui obtained his bachelor’s degree in engineering mechanics from Nanjing University of Aeronautics and Astronautics in China. He got his PhD in mechanical engineering at the University of Toronto where he developed novel experimental techniques to investigate the nanomechanics of 2D materials. Currently, Dr. Cui is a postdoctoral fellow at Stanford University where he works with Prof. William Chueh (Materials Science) and Prof. Wendy Gu (Mechanical Engineering) on the electro-chemo-mechanics of solid-state batteries. Dr. Cui aims to apply his diverse expertise spanning nanomechanics, electrochemistry, and in-situ characterization to solve grand societal challenges related to energy and sustainability. Dr. Cui has received the postdoctoral fellowship from Natural Sciences and Engineering Research Council of Canada (NSERC), and future faculty poster award from Society of Engineering Science (SES). 

https://columbiauniversity.zoom.us/j/96224555800?pwd=WGROVHo0cE1LUHB4Y2NhSDdtUGxSQT09

Meeting ID: 962 2455 5800 Security: 126323