SKM 2021 – wissenschaftliches Programm
CPP 8.11: Poster
Mittwoch, 29. September 2021, 17:30–19:30, P
Influence of Mg on the structure and electrolyte/electrode interface in all-solid-state lithium battery — •Yuxin Liang and Peter Müller-Buschbaum — Technische Universität München, Fakultät für Physik, Lehrstuhl für Funktionelle Materialien, James-Franck-Str.1, 85748 Garching, Germany
The interest in all-solid-state lithium battery mainly stems from its high safety and energy density compared with conventional Li-ion batteries. Solid polymer electrolytes (SPEs) as an essential component with high durability, long shelf life, high energy density, great flexibility for cell design and light in weight are considered as the most promising material for the next generation batteries. However, as the most common SPE, poly(ethylene oxide) (PEO) electrolytes have limited electrochemical windows and can react with lithium metal to form a solid electrolyte interphase (SEI), meaning that such SPE is more instable in high-energy-density batteries. Moreover, inhomogeneity at the electrolyte/electrode interface, with or without a SEI, can elicit an irregular lithium plating that leads to dendrite formation, resulting in the cycle life reduction and total cell resistance increase. As a modifying strategy, adding inorganic particles can alter the degree of non-conducting crystalline polymer volume within the electrolyte, promote the dissociation of Li+-TFSI- ion pairs and increase the amount of mobility Li+ ions. Herein, Mg(ClO4)2 is introduced to the PEO electrolyte to modify the structure of SPE and increase the ionic conductivity. Besides, the additive can also assist in constructing a Li+ conducting SEI at the electrolyte/electrode interface.