Abstract
While the potential use of copolymerized electrolytes in Li metal batteries is subject to intense investigation, the fundamental understanding of the nanoscale domain formation and its effect on Li+transport is still lacking. In this study, we investigated the correlation between the Li+transport mechanism and the miscibility of monomers in polymer blend electrolytes derived from the in situ copolymerization of methyl methacrylate (MMA) and vinylene carbonate (VC) in the presence of polyethylene glycol dimethyl ether (PEGDME) plasticizer and bis(trifluoromethanesulfonyl)imide (LiTFSI) salt. The addition of a polar short chain plasticizer reduced the dynamic and structural heterogeneities of the electrolyte. Small-angle X-ray scattering (SAXS) measurements and coarse-grained molecular dynamics (MD) simulations were used to investigate the nanoscale structure of the electrolytes. The distribution of relaxation times corresponding to the three distinct diffusion mechanisms of the free and interfacial Li+ions at the copolymer/plasticizer and electrolyte/SEI boundaries was analyzed in a broad temperature range to elucidate the Li+transport mechanism. The chemical composition of the SEI and the contribution of a ceramic lithium lanthanum zirconium oxide (LLZO, Li7La3Zr2O12) phase on the interfacial resistance, salt degradation, and SEI stability were studied by X-ray photoelectron spectroscopy (XPS) depth profile analysis and electrochemical testing.
| Original language | English |
|---|---|
| Pages (from-to) | 30973-30985 |
| Number of pages | 13 |
| Journal | ACS Nano |
| Volume | 19 |
| Issue number | 34 |
| DOIs | |
| State | Published - Sep 2 2025 |
Funding
This research at Oak Ridge National Laboratory, managed by UT Battelle LLC, for the US Department of Energy (DOE) under contract DE-AC05-00OR22725, was sponsored by the DOE Vehicle Technologies Office (Grant#1.1.5.511; Program Manager: Haiyan Croft). We also acknowledge partial support from the ORNL Laboratory Directed Research and Development Fund. This research used the resources of the Center for Nanophase Materials Sciences (CNMS) and Spallation Neutron Source (SNS), which are DOE Office of Science User Facilities. This research used resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the US Department of Energy under Contract No. DE-AC05-00OR22725. Part of the MD simulations was performed at the National Energy Research Scientific Computing Center (NERSC), a DOE Office of Scientific User Facility supported by the DOE Office of Science under Contract DE-AC02-05CH11231. Notice: This manuscript has been authored by UT-Battelle LLC under contract DE-AC05–00OR22725 with the US Department of Energy (DOE). The US government retains and the publisher, by accepting the article for publication, acknowledges that the US government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for US government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan ( http://energy.gov/downloads/doe-public-access-plan ).
Keywords
- electrospinning
- in situ polymerization
- Li metal
- polymer blend electrolyte
- solid-state battery