Evaluation and Improvement of the Stability of Poly(ethylene oxide)-based Solid-state Batteries with High-Voltage Cathodes |
| |
Authors: | Yuriy Yusim Enrico Trevisanello Dr. Raffael Ruess Dr. Felix H. Richter Dr. Alexander Mayer Dr. Dominic Bresser Prof. Dr. Stefano Passerini Prof. Dr. Dr. h.c. Jürgen Janek Dr. Anja Henss |
| |
Affiliation: | 1. Institute of Physical Chemistry, Justus Liebig University Giessen, Heinrich-Buff-Ring 17, 35392 Giessen, Germany;2. Helmholtz Institute Ulm (HIU), Helmholtzstraße 11, 89081 Ulm, Germany |
| |
Abstract: | Solid-state batteries (SSBs) with high-voltage cathode active materials (CAMs) such as LiNi1−x−yCoxMnyO2 (NCM) and poly(ethylene oxide) (PEO) suffer from “noisy voltage” related cell failure. Moreover, reports on their long-term cycling performance with high-voltage CAMs are not consistent. In this work, we verified that the penetration of lithium dendrites through the solid polymer electrolyte (SPE) indeed causes such “noisy voltage cell failure”. This problem can be overcome by a simple modification of the SPE using higher molecular weight PEO, resulting in an improved cycling stability compared to lower molecular weight PEO. Furthermore, X-ray photoelectron spectroscopy analysis confirms the formation of oxidative degradation products after cycling with NCM, for what Fourier transform infrared spectroscopy is not suitable as an analytical technique due to its limited surface sensitivity. Overall, our results help to critically evaluate and improve the stability of PEO-based SSBs. |
| |
Keywords: | Cell Failure High Voltage Cathodes Interface Stability Poly(ethylene Oxide) Solid-State Batteries |
|
|