In-Situ Formed Protecting Layer from Organic/Inorganic Concrete for Dendrite-Free Lithium Metal Anodes

Nano Lett. 2020 May 13;20(5):3911-3917. doi: 10.1021/acs.nanolett.0c01085. Epub 2020 Apr 27.

Abstract

In this work, a separator modified by composite material of graphite fluoride nanosheets and poly(vinylidene difluoride) (GFNs-PVDF) is fabricated to in-situ construct a protective layer on Li metal anodes. The much-improved mechanical properties of this organic/inorganic protecting layer ensure efficient restriction on the growth of Li dendrites. The LiF and graphene nanosheets generated by the reaction of GFNs with lithium metal can not only provide fast transport channels for Li ions but also protect the Li metal anode from continuous corrosion of electrolytes. In addition, GFNs' lithiophilic nature guarantees the uniform Li nucleation site and perfect contact between li metal and the protecting layer without void space, leading to a low interfacial impedance and layer-by-layer lithium deposition. Together with the scalable method and cheap raw materials, this strategy provides new insights toward practical applications of Li metal batteries.

Keywords: Fluorinated graphite; composite protective layer; dendrite-free; in-situ generation; lithium metal batteries.