Crosslinked perfluoropolyether solid electrolytes for lithium ion transport

Devaux, Didier; Villaluenga, Irune; Bhatt, Mahesh; Shah, Deep; Chen, X. Chelsea; Thelen, Jacob L.; DeSimone, Joseph M.; Balsara, Nitash P.

doi:10.1016/j.ssi.2017.08.007

DOE OSTI · 1476567

Crosslinked perfluoropolyether solid electrolytes for lithium ion transport

Devaux, Didier·Villaluenga, Irune·Bhatt, Mahesh·Shah, Deep·Chen, X. Chelsea·Thelen, Jacob L.·DeSimone, Joseph M.·Balsara, Nitash P.

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Abstract

Perfluoropolyethers (PFPE) are commercially available non-flammable short chain polymeric liquids. End-functionalized PFPE chains solvate lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt and these mixtures can be used as electrolytes for lithium (Li) batteries. Here we synthesize and characterize a new class of solid PFPE electrolytes. The electrolytes are made by either thermal or UV crosslinking PFPE chains with urethane methacrylate end-groups. For the synthesis of thermally crosslinked electrolytes, polyhedral oligomeric silsesquioxane (POSS) with organic acrylopropyl groups was used as crosslinker agent, while for UV cured electrolytes a photoinitiatior was used. We present thermal, morphological, and electrical data of the solid electrolytes. We compare these properties with those of the two parent liquids (PFPE with urethane methacrylate end-groups and POSS with acrylopropyl groups) mixed with LiTFSI. The solubility limit of LiTFSI in the PFPE-based solids is higher than that in the liquids. The conductivity data are analyzed using the Vogel–Tamman–Fulcher equation. In conclusion, the concentration of effective charge carriers is a strong function of the nature of the solvent (solid versus liquid) whereas the activation energy is neither a strong function of the nature of the solvent nor salt concentration.

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25 ENERGY STORAGE crosslinked electrolyte lithium battery perfluoropolyether polyhedral oligomeric silsesquioxane solid electrolyte

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Devaux, Didier, Villaluenga, Irune, Bhatt, Mahesh, Shah, Deep, Chen, X. Chelsea, Thelen, Jacob L., DeSimone, Joseph M., Balsara, Nitash P.. 2017-08-17. Crosslinked perfluoropolyether solid electrolytes for lithium ion transport. https://doi.org/10.1016/j.ssi.2017.08.007

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