PhD Student Matthias Weiling from Helmholtz Institute Münster Wins Poster Prize

Matthias Weiling, together with his co-authors from Helmholtz Institute Münster, wins the poster prize of the battery conference "Swiss Battery Days 2023".

06 October 2023 – With his poster, PhD student Matthias Weiling from Helmholtz Institute Münster (HI MS; IEK-12) of Forschungszentrum Jülich shows how measurement methods for the investigation of interphases can be improved. Together with his co-authors Felix Pfeiffer and Jian-Fen Wang from the Young Investigator Group " Interfacial Spectroelectrochemistry" headed by Dr Masoud Baghernejad, he convinced the conference participants of the "Swiss Battery Days 2023" symposium, who could vote for the best poster. He received the "Best Poster Award", which is endowed with 500 CHF.

Method for the Investigation of Solid Electrolyte Interphases

The winning poster deals with a method to study solid electrolyte interphases (SEI). Weiling and his team looked at SEI using operando attenuated total reflection Fourier-Transform Infrared Spectroscopy (ATR-FTIR) under real conditions in a lithium-ion battery (LIB) cell. In this work, they compared the formation and composition of SEI respectively with and without electrolyte additives on silicon electrodes.

Using the developed method, different degradation products of 2-sulfobenzoic acid anhydride in the SEI on silicon were detected at different cell voltages.

Doubling the Cycle Life of High-Voltage Cells

In addition, the poster shows that the electrolyte additives used, 2-sulfobenzoic acid anhydride and lithium difluorophosphate, double the cycle life of high-voltage cells with NMC811 as the cathode material and 20 percent silicon oxide-containing graphite anodes. This is mainly due to the SEI formed by the electrolyte containing the additive 2-sulfobenzoic acid anhydride.

A comprehensive understanding of the mode of action of electrolyte additives as well as the interphases on electrode materials is necessary to develop tailored electrolytes for the next generation of LIB.

The results were obtained as part of the project "Electrolyte Formulations for Lithium Batteries" (EFoBatt), which is funded by the German Federal Ministry of Education and Research (BMBF).

Further information on the Young Investigator Group "Interfacial Spectroelectrochemistry"