(644f) Hybrid Polymer-Liquid Electrolytes: Understanding Electrode-Electrolyte Interfaces for Next-Generation Lithium-Ion Batteries

Hybrid electrolytes (HEs) have emerged as a promising alternative to traditional liquid electrolytes for use in next-generation lithium-ion batteries. HEs combine the advantages of both solid and liquid electrolytes, offering improved safety, stability, and conductivity, while also enabling more flexible electrode design. A promising example of HEs are polymer-liquid electrolytes¹ such as the structural battery electrolyte (SBE) where two discrete co-existing phases are formed: one thermoset structural phase providing mechanical integrity and one percolating liquid ion-conducting phase. The phase separation is possible as a result of the variations in the solubility parameters of the monomers with respect to those of the formed polymers. The main feature of the polymer network is the microporous structure that gives structural integrity to the system thanks to the polymeric solid phase and, at the same time, conducts the ions through the percolating liquid phase.

The electrode-electrolyte interface is a critical factor in determining the performance and longevity of lithium-ion batteries using HEs. This interface is affected by various factors, including the HE composition, electrode surface properties, and the nature of the electrochemical reactions taking place. The interaction between the HE and the electrode can lead to the formation of a passivation layer (SEI-solid electrolyte interface), which can impede the flow of ions and reduce the battery's performance.

In this study, the compatibility and stability of HEs with different commercial electrode materials have been studied. Morphological analysis was coupled with chemical analysis in order to better evaluate the electrochemical performances of the system.

Swedish Energy Agency, grant #48488, is gratefully acknowledged for financial support.

[1] M. Cattaruzza, Y. Fang, I. Furó, G. Lindbergh, F. Liu and M. Johansson, Journal of Materials Chemistry A, 2023, 11, 7006-7015.