CO2-sourced polycarbonates as solid electrolytes for room temperature operating lithium batteries. Issue 16 (2nd April 2019)

• Record Type: Journal Article
• Authors: Ouhib, Farid; Meabe, Leire; Mahmoud, Abdelfattah; Eshraghi, Nicolas; Grignard, Bruno; Thomassin, Jean-Michel; Aqil, Abdelhafid; Boschini, Frederic; Jérôme, Christine; Mecerreyes, David; Detrembleur, Christophe
• Is Part Of: Journal of materials chemistry. Volume 7:Issue 16(2019)
• Page Start: 9844
• Page End: 9853
• Publication Date: 2019-04-02
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c9ta01564g
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : A CO2 -sourced self-standing solid electrolyte membrane is prepared and evaluated for room temperature operating lithium batteries. Abstract : In the last few years, polycarbonates have been identified as alternatives to poly(ethylene oxide) as polymer electrolytes for lithium battery applications. In this work, we show the design of CO2 -sourced polycarbonates for their use in room temperature operating lithium batteries. Novel functional polycarbonates with alternating oxo-carbonate moieties and polyethylene oxide segments are synthesized by the facile room temperature (rt) organocatalyzed polyaddition of CO2 -sourced bis(α-alkylidene carbonate)s (bis-αCCs) with polyethylene oxide diols. The effect of the molar mass of polyethylene oxide on the ionic conductivity and thermal properties of poly(oxo-carbonate)s is investigated. The best candidate shows a low glass transition temperature of −44 °C and a high ionic conductivity of 3.75 × 10 −5 S cm −1 at rt when loaded with 30 wt% bis(trifluoromethanesulfonyl)imide salt (LiTFSI) without any solvent. An all-solid semi-interpenetrated network polymer electrolyte (SIN-SPE) is then fabricated by UV cross-linking of a mixture containing specifically designed poly(oxo-carbonate) bearing methacrylate pendants, diethylene glycol diacrylate and the previously described poly(oxo-carbonate) containing LiTFSI. The resulting self-standing membrane exhibits a high oxidation stability up to 5 V ( vs. Li/Li + ), an ionic conductivity of 1.1 × 10 −5 S cm −1 at rt (10 −4 S cm −1 at 60 °C) and promising mechanical properties. Assembled in a half cell configuration with LiFePO4 (LFP) as the cathode and lithium as the anode, the all-solid cell delivers a discharge capacity of 161 mA h g −1 at 0.1C and 60 °C, which is very close to the theoretical capacity of LFP (170 mA h g −1 ). Also, a stable reversible cycling capacity over 400 cycles with a high coulombic efficiency of 99% is noted at 1C. Similar results are obtained at rt provided that 10 wt% tetraglyme as a plasticizer was added to the SIN-SPE.