TY  - JOUR
AU  - Stolz, Lukas
AU  - Homann, Gerrit
AU  - Winter, Martin
AU  - Kasnatscheew, Johannes
TI  - Realizing poly(ethylene oxide) as a polymer for solid electrolytes in high voltage lithium batteries via simple modification of the cell setup
JO  - Materials advances
VL  - 2
IS  - 10
SN  - 2633-5409
CY  - Cambridge
PB  - Royal Society of Chemistry
M1  - FZJ-2021-01769
SP  - 3251-3256
PY  - 2021
AB  - Pure, i.e., linear poly(ethylene oxide)-based solid polymer electrolyte (PEO-based SPE) as a common benchmark system for Li metal batteries (LMBs) is frequently assumed to be unsuitable for high voltage applications e.g., with LiNi0.6Mn0.2Co0.2O2 (NMC622)-based cathodes. In fact, a destructive failure appears immediately after cell operation, seen by a random-like “voltage noise” during charge, rendering continuous charge/discharge cycling in e.g., NMC622||Li cells not possible. Counterintuitively, this failure is a result of short-circuits in the course of e.g., Li dendrite penetration. It is shown that the distance between the electrodes plays a crucial role. This failure is more likely with a lower distance, particularly when the SPE is mechanically prone to shrinkage, for example at higher temperatures as systematically revealed by mechanical compression tests. Additionally, the active mass loading has a crucial impact on short circuits, and thus the “voltage noise” failure, as well. An effective and practically simple solution to realize cell operation with a PEO-based SPE is the incorporation of a spacer between the electrodes. This modification prevents the detrimental shrinkage and enables charge/discharge cycling performance in NMC622||Li cells with a defined and constant electrode distance, thus without voltage noise, and finally fulfills a reasonable benchmark for systematic R&D with specific capacities above 150 mA h g−1 even at 40 °C.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000639982700001
DO  - DOI:10.1039/D1MA00009H
UR  - https://juser.fz-juelich.de/record/891849
ER  -