Nanocomposite solid polymer electrolytes based on semi-interpenetrating hybrid polymer networks for high performance lithium metal batteries. (1st September 2020)

• Record Type: Journal Article
• Authors: Fedeli, Elisabetta; Garcia-Calvo, Oihane; Thieu, Tho; Phan, Trang N.T.; Gigmes, Didier; Urdampilleta, Idoia; Kvasha, Andriy
• Is Part Of: Electrochimica acta. Volume 353(2020)
• Publication Date: 2020-09-01
• Subjects: Lithium metal solid state battery -- Nanocomposite solid polymer electrolyte -- POSS -- Semi interpenetrating solid polymer network -- High voltage cathode; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2020.136481
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: This research reports the synthesis of nanocomposite solid polymer electrolytes (ncSPEs) for solid state lithium metal batteries. These materials are composed of a controlled hybrid organic-inorganic network of glycidyl POSS® and Jeffamine® ED2003, in which linear high molecular weight poly (ethylene oxide) (PEO) chains are entangled to improve both mechanical and electrochemical properties of the ncSPE. Synthesis and preparation of self-standing membranes are achieved with a facile one-pot catalyst-free method with considerably reduced amount of organic solvent, which is a plus toward a future scale-up. We found that the component ratio plays a crucial role in ncSPEs' performance as a simple variation (i.e. cross-linking degree) is sufficient to completely change the electrochemical behavior of the solid state cell. For instance, increasing POSS® amount guarantees better resistance to lithium dendrites penetration, better electro-oxidation stability, and significantly extends cycle life in Li/ncSPE/LiFePO4 solid state cells. Furthermore, besides improving cell performance at higher C-rate of Li/LiFePO4 cells, this PEO-based ncSPE gives better response than reference PEO-LiTFSI electrolyte in high voltage Li/LiNi0.6 Mn0.2 Co0.2 O2 cells with up to 10 cycles at 60 °C with discharge capacity retention above 80%. Despite the poor performance, to the best of our knowledge, this electrolyte is one of the few examples of PEO-based solid polymer electrolytes being capable of cycling with high voltage cathodes. Highlights: Nanocomposite solid polymer electrolytes (ncSPE) with POSS®-Jeffamine®-PEO prepared. NcSPEs architectures are achieved as semi-interpenetrating polymer networks. Component ratio affects ncSPEs' mechanical and electrochemical properties. Improved cyclability of Li/ncSPE/LiFePO4 cells with thick cathodes achieved. NcSPE demonstrated improved stability vs PEO-LiTFSI in Li/NMC622 cells.