A CF4 plasma functionalized polypropylene separator for dendrite-free lithium metal anodes. Issue 14 (20th March 2023)

• Record Type: Journal Article
• Authors: Cao, Shengling; He, Xin; Chen, Manlin; Han, Yu; Wang, Kangli; Jiang, Kai; Zhou, Min
• Is Part Of: Journal of materials chemistry. Volume 11:Issue 14(2023)
• Page Start: 7545
• Page End: 7555
• Publication Date: 2023-03-20
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d2ta09763j
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : A simple and effective plasma functionalization technique for grafting fluorine-containing functional groups on commercial PP separators to induce the formation of LiF-rich SEI films has been proposed. Abstract : Lithium metal is recognized as a promising anode material for next-generation high-energy-density batteries, but uncontrollable lithium dendrites inhibit their further applications. In this paper, fluorine-containing functional groups were grafted on a commercial polypropylene (PP) separator by a simple and efficient plasma functionalization technique. The grafted polar groups enhance the affinity of the PP separator for Li-ions, thus resulting in improved wettability and ion conductivity as well as an enhanced lithium-ion transference number of the separator. Moreover, the introduced fluorine-containing functional groups participate in the formation of a LiF-rich solid electrolyte interface (SEI) film, which regulates the uniform deposition of lithium ions and inhibits lithium dendrite growth. As a result, Li‖Li symmetric batteries equipped with fluorinated PP separators exhibit a long lifespan of nearly 7000 h (1 mA cm −2, 1 mA h cm −2 ) with a low overpotential of 48 mV. This work introduces a simple method to induce the formation of a LiF-rich SEI film, which can be extended to a variety of energy storage systems and provides new routes for the construction of high-performance energy storage technologies.