Understanding the Mechanics of Polymeric Materials in Emerging Electronic Applications – From Molecular Scale to Application

• Applicant: Dr. Lukas Michalek
• Subject Area: Polymer Materials ; Experimental and Theoretical Physics of Polymers ; Solid State and Surface Chemistry, Material Synthesis ; Synthesis and Properties of Functional Materials ; Preparatory and Physical Chemistry of Polymers
• Term: from 2021 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 456522816

To facilitate societies growing demand for mobile electronics suitable energy storage systems are needed. The requirements for such novel battery technologies are extensive due to the increased power consumption of modern electronic devices and the growing demand of high energy densities. High-performance, low-cost batteries with high specific capacity and extended lifetime are desperately needed. A promising alternative to commonly employed electrode materials is the adoption of lithium metal as a negative electrode. Yet, the naturally formed unstable solid electrolyte interphase (SEI) layer, combined with the uncontrolled formation of lithium dendrites, limits the application of lithium metal anodes. By directly applying an adaptive polymer coating on the lithium metal electrode the instability of the SEI and the accompanying instability of Coulombic efficiency can be improved. While the importance of the mechanical properties of the employed polymer coatings is undeniable, a precise molecular understanding, and characterization of the mechanics of the employed polymer coatings is still missing. Precise characterization of the mechanics, from molecular- to device-level, will facilitate understanding of the correlation between mechanic properties and the device performance and lead to the development of novel polymer coatings for lithium metal electrode batteries.In order to develop and design new polymer coatings for battery applications, a better understanding of the polymers and the inherent material properties is essential. In particular, the influences of the chemical and physical properties on a device’s performance are of highest interest. By implementing weak and strong binding sites into a polymer network, excellent energy dissipation combined with exceptional material integrity can be introduced, resulting in tough and highly stretchable, self-healing elastomers. The investigation of polymeric material from a molecular level is indispensable to comprehensively understand the effect of molecular properties on the resulting material properties and subsequently on the device performance. Therefore, the proposed research project is focusing on corelative analysis of mechanical properties, starting with the precise investigation of molecular chain mechanics (Part I), towards the characterization of nano-mechanics in polymeric networks (Part II). The mechanic properties of the tested macromolecules and polymeric networks will be correlated with the device (battery) performance (Part III). The understanding gained will be subsequently used to develop new materials with increased performance in electronic devices (Part IV). The introduced feedback-loop provides a systematic path to improve a device’s performance through understanding the material properties on a molecular, micro and application level – exceeding the currently used inefficient trial-and-error approach of existing systems.

• DFG Programme: WBP Fellowship
• International Connection: USA
• Host: Professorin Zhenan Bao, Ph.D.