Enhanced Cycling Performance of Li‐O2 Batteries by the Optimized Electrolyte Concentration of LiTFSA in Glymes. Issue 4 (10th December 2012)

• Record Type: Journal Article
• Authors: Li, Fujun; Zhang, Tao; Yamada, Yuki; Yamada, Atsuo; Zhou, Haoshen
• Is Part Of: Advanced energy materials. Volume 3:Issue 4(2013:Apr.)
• Page Start: 532
• Page End: 538
• Publication Date: 2012-12-10
• Subjects: Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.201200776
• Languages: English
• ISSNs: 1614-6832

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>A series of non‐aqueous electrolytes were prepared by dissolving lithium bis(trifluoromethylsulfonyl)amide (LiTFSA) in triglyme and tetraglyme (G<italic>x</italic>, <italic>x</italic> = 3 and 4), respectively, with varied molar ratios. With the electrolytes the cycling performance of Li‐O<sub>2</sub> batteries showed a strong dependence on the molar ratios between LiTFSA and Gx. It was found that the molar ratio of 1 to 5 was critical for the cycling‐performance of Li‐O<sub>2</sub> batteries. High stability over 20 discharge–recharge cycles at 500 mA/g<sub>carbon</sub> and in an O<sub>2</sub> flow was obtained in LiTFSA‐(Gx)<sub>5</sub> (<italic>x</italic> = 3 and 4). The discharge product at cathode could be directly detected and identified as the dominant crystalline product Li<sub>2</sub>O<sub>2</sub> on the 1st and 20th discharged electrodes using X‐ray diffraction technique (XRD), which indicates rechargeability and feasibility of the electrolytes LiTFSA‐(Gx)<sub>5</sub> (<italic>x</italic> = 3 and 4) for Li‐O<sub>2</sub> batteries. At 1000 mA/g<sub>carbon</sub> their capacities could be stabilized for 10 cycles. To our knowledge, this behavior of dependence of cycling performance of Li‐O<sub>2</sub> batteries on the concentration of Li salts is presented here for the first time, and it may be extended to other Li salts and solvents and suggest a new route for screening cycling‐stable electrolytes for Li‐O<sub>2</sub> batteries.</p> </abstract>