Gas Evolution in Lithium-Ion Batteries: Solid versus Liquid Electrolyte

Florian Strauss; Jun Hao Teo; Alexander Schiele; Timo Bartsch; Toru Hatsukade; Pascal Hartmann; Jürgen Janek; Torsten Brezesinski

doi:10.1021/acsami.0c02872

Gas Evolution in Lithium-Ion Batteries: Solid versus Liquid Electrolyte

ACS Appl Mater Interfaces. 2020 May 6;12(18):20462-20468. doi: 10.1021/acsami.0c02872. Epub 2020 Apr 24.

Authors

Florian Strauss¹, Jun Hao Teo¹, Alexander Schiele¹, Timo Bartsch¹, Toru Hatsukade¹, Pascal Hartmann^{1

2}, Jürgen Janek^{1

3}, Torsten Brezesinski¹

Affiliations

¹ Battery and Electrochemistry Laboratory, Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, Eggenstein-Leopoldshafen 76344, Germany.
² BASF SE, Carl-Bosch-Strasse 38, Ludwigshafen 67056, Germany.
³ Institute of Physical Chemistry & Center for Materials Science, Justus-Liebig-University Giessen, Heinrich-Buff-Ring 17, Giessen 35392, Germany.

PMID: 32275815
DOI: 10.1021/acsami.0c02872

Abstract

Gas evolution in conventional lithium-ion batteries using Ni-rich layered oxide cathode materials presents a serious issue that is responsible for performance decay and safety concerns, among others. Recent findings revealed that gas evolution also occurred in bulk-type solid-state batteries. To further clarify the effect that the electrolyte has on gassing, we report in this work-to the best of our knowledge-the first study comparing gas evolution in lithium-ion batteries with NCM622 cathode material and different electrolyte types, specifically solid (β-Li₃PS₄ and Li₆PS₅Cl) versus liquid (LP57). Using isotopic labeling, acid titration, and in situ gas analysis, we show the presence of O₂ and CO₂ evolution in both systems, albeit with different cumulative amounts, and possible SO₂ evolution for the lithium thiophosphate-based cells. Our results demonstrate the importance of considering gas evolution in solid-state batteries, especially the formation and release of highly corrosive SO₂, due to side reactions with the electrolyte.

Keywords: all-solid-state battery; gas evolution; interfacial chemistry; lithium thiophosphate solid electrolyte; lithium-ion battery; organic carbonate liquid electrolyte.