Abstract

To overcome the limitations of its individual constituents, polymer–ceramic hybrid solid electrolytes are currently explored as promising materials class to leverage advantages of each constituent, that is, sufficiently high ionic conductivity of ceramics and superior mechanical flexibility of the polymer. Such systems may provide unexpectedly high ionic conductivities, though actual origins of this observation are still under discussion. In practice, hybrid electrolytes may be produced invoking active or non-active ceramic fillers or upon grafting of polymers to oxidic particles, often with up to 20 wt-% of ceramic components.

Considering the increasing demand for affordable but high energy density batteries for various applications, significant efforts are devoted to enable thin lithium metal electrodes despite their challenges of inhomogeneous lithium deposition or loss of lithium inventory. Grafted hybrid-polymer electrolytes demonstrated tolerance against Li dendrites while providing reasonable cell performance, provided that the often porous cathodes may be polymer-infiltrated or operated with catholytes. The present work introduces salient aspects of polymer electrolytes, including extrusion processing of hybrid polymerceramic electrolytes, thereby highlighting the viability of dry processing, while also analyzing the fate of ceramic fillers and particle size distribution(s) within the hybrid-polymer membranes upon cycling.

In addition, to bestow sufficient compatibility of Li metal electrodes at demanding cell operation conditions, host structures from electro-spun scaffolds that accommodate lithium deposition may be employed to boost reversibility of lithium inventory, whereas imaging data from 3D-SEM reconstructions reveal variations of particle size distributions and are evaluated as input structures for numerical simulation. The latter reflects localized ionic conductivities of grafted domains in the hybrid materials while providing insights that could pave ways for better design strategies of hybrid polymer-ceramic materials, thereby resolving governing mechanistic details of enhanced ionic conductivities and hence faster charge capabilities of polymer-based Li metal cells.

After an introduction into the polymer electrolyte and its history, main results of recent R&D in Münster will be presented.

Bio

Martin Winter has been researching in the field of electrochemical energy storage and conversion for more than 35 years. His focus is on the development of new materials, components and cell designs for lithium-ion, lithium-metal batteries and alternative battery systems. Martin Winter currently holds a professorship for “Materials Science, Energy and Electrochemistry” at the Institute of Physical Chemistry at University of Münster, Germany.

Martin Winter is founder and scientific director of MEET Battery Research Center at University of Münster. MEET stands for “Münster Electrochemical Energy Technology”. Since 2015, he is also the founding director of Helmholtz Institute Münster HI MS “Ionics in Energy Storage”, an institute branch of Forschungszentrum Jülich, a big National Lab in Germany. MEET and HI MS are internationally recognized institutions in research and development of innovative electrochemical energy storage systems. Martin Winter has received more than 70 scientific awards and recognitions.

https://www.uni-muenster.de/MEET/en/team/winter.shtml

https://www.fz-juelich.de/profile/winter_m

Hosted by: Jeff Sakamoto