Modelling Approach to Assess Electrochemical Compatibility of Electrode/Solid Polymer Electrolyte Interface in All-Solid-State Battery

Description

Nowadays the research for the next-generation batteries has intensified, driven by national and international policies. In this context, All-Solid-State Battery (ASSB) has gained in interest as a
promising solution to make batteries safer while boosting their energy density. On top of the bulk properties of electrolyte and active materials, the stability of both cathode and anode interfaces is a key
factor for long-term high performance. Electrochemical degradation of the interface can lead to the battery capacity fading and internal impedance rising as the active material is consumed and a new phase
forms. Nevertheless, characterizing heterogeneous interfaces at atomistic scale presents formidable challenges, particularly through experimental methods that necessitate specialized testing facilities (in-
situ and/or operando techniques). (Ab initio and reactive) Molecular Dynamics have emerged as a valuable tool to investigate buried interfaces.

Recently, Relative Bond length Change (RBC) analysis was combined with AIMD simulations to study the long-term stability and compatibility of a broad range of Solid Polymer Electrolytes (SPEs) with key
negative/positive electrode materials (graphite, silicon, lithium, LFP, NMC)[1]. This approach, i.e. coupling RBC analysis and AIMD, enabled straightforward analysis of (electro)chemical degradation
during dynamic calculations. The results highlighted how the functional groups interactions with electrodes affect their long-term stability and reactivity. Bond length distributions were found to respond
to environmental changes and relate to the long-term reactivity. Furthermore, the balancing of the SPE polymer mobility and functional group–electrode surface attraction, respectively, kinetic and
thermodynamic properties, further suggests a selective spatial orientation of functional groups when exposed to an electric field, which could have great implications for low-temperature and high-current-
density environments. The obtained knowledge on how reactive key SPE polymer functional groups are and also how their reactivity changes in terms of the electric field orientation effect could provide new
insights for designing new stable SPE polymers.

[1] L. Bekaert. 126 (2022) 8227-8237, DOI: 10.1021/acs.jpcc.2c01144

Period	11 Sept 2025
Event title	76th Annual Meeting of the International Society of Electrochemistry: Electrochemistry: From Basic Insights to Sustainable Technologies
Event type	Conference
Location	Mainz, Germany, Rhineland-PalatinateShow on map
Degree of Recognition	International