In situ electro-chemo-mechanics of electrode degradation

2018年07月03日

报告题目:In situ electro-chemo-mechanics of electrode degradation

报告人:Prof. Ting Zhu, Georgia Institute of Technology, USA

时间: 7月5日(周四)下午4:00

地点:化学楼601会议室

摘要:
    Rechargeable batteries play a critical role in the emerging renewable energy landscape. However, they often suffer from the electrochemically-induced mechanical degradation in high capacity electrodes, resulting in fast capacity fade and reduced cycle life. Using a nanoscale battery cell inside transmission electron microscope, we made in situ observations of reaction, deformation and fracture in individual nanowire and nanoparticle electrodes. A wide range of novel phenomena were discovered, including the size-dependent fracture in Si nanoparticles, co-lithiation/delithiation of Si/Ge nanowire array anodes for Li-ion batteries, degradation of nanoparticle-shell architectures in Li2S cathodes for Li-S batteries, and nanoscale Li dendrite growth under controlled chemomechanical loads, etc. We developed continuum and atomistic models to reveal the mechanistic origin of stress generation and mechanical failure in these high-capacity electrode materials. The associated simulation results provide insights into the microstructural evolution and degradation in nanoscale building blocks of battery electrodes, and have broad implications for designing the durable electrodes in high performance rechargeable batteries.



报告人简介:
    Ting Zhu is the professor and Woodruff Faculty Fellow in the George W. Woodruff School of Mechanical Engineering at Georgia Institute of Technology. He received Ph.D. in solid mechanics from Tsinghua University in 1999 and Ph.D. in mechanical engineering from Massachusetts Institute of Technology in 2004. He worked as a postdoctoral associate at Harvard University between 2004 and 2005. He joined Georgia Tech as an assistant professor in fall 2005. He received the Sia Nemat-Nasser Early Career Award from the American Society of Mechanical Engineers, the Young Investigator Medal from the Society of Engineering Science, and the Yue-Kong Pao Visiting Chair Professorship from Zhejiang University. He current research include the studies of ultrahigh strength in nanotwinned metals; electrode degradation in lithium-ion batteries; dislocation and twinning mechanisms in metallic nanostructures; fracture in 2D materials; 3D printing of metals; strengthening mechanisms in high entropy alloys; irradiation damage of nuclear materials; hydrogen embrittlement of steels; nanostructured shape memory alloys; and development of multiscale modeling methods. His research results have been published in Nature,Nature Materials,Nature Nanotechnology, Progress in Materials Science, PANS,Nature Communications, Energy & Environmental Science, Advanced Materials, Advanced Energy Materials, Physical Review Letters, ACS Nano, Nano Letter etc. (H-index 45)