@article{12fadf5e035f49ef94cc0700f10bb9da,
title = "Application of ionic liquid as K-ion electrolyte of graphite//K2Mn[Fe(CN)6] cell",
abstract = "A binary ionic liquid of K[FSA]-[C3C1pyrr][FSA] (2:8 in molar ratio) in which N-methyl-N-propylpyrrolidinium and bis(fluorosulfonyl)amide are abbreviated as [C3C1pyrr] and [FSA], respectively, is applied as an electrolyte of K-ion batteries for the first time. A graphite composite electrode with sodium carboxymethylcellulose as the binder undergoes reversible potassium intercalation, forming a KC8 compound in a K half-cell filled with the binary ionic liquid as electrolyte. Because the K[FSA]-[C3C1pyrr][FSA] does not corrode an Al foil current collector even with polarization of up to 6 V versus K+/K, a K2Mn[Fe(CN)6] positive electrode yields a highly reversible capacity of 134 mAh g-1 at ca. 4.0 V. We demonstrate a K-ion battery of graphite//K2Mn[Fe(CN)6] configuration with an ionic liquid electrolyte that exhibits stable charge and discharge properties over 200 cycles at room temperature. The redox performance is significantly improved by replacing the conventional KPF6 carbonate ester solution with the ionic liquid. ",
author = "Hiroo Onuma and Kei Kubota and Shotaro Muratsubaki and Tomooki Hosaka and Ryoichi Tatara and Takayuki Yamamoto and Kazuhiko Matsumoto and Toshiyuki Nohira and Rika Hagiwara and Hiroshi Oji and Satoshi Yasuno and Shinichi Komaba",
note = "Funding Information: The authors are grateful to Dr. T. Ichihashi and Prof. Y. Idemoto in Tokyo University of Science for TEM measurements. This study was partly funded by the MEXT program “ESICB” (JPMXP0112101003), the JST through A-Step program (AS282S001d), and JSPS KAKENHI (Grant No. 20H02849). The synchrotron radiation experiment was conducted with the approval of the Japan Synchrotron Radiation Research Institute (Proposal Nos. 2016A1536 and 2017B1585). Funding Information: AcknowledgmentsThe authors are grateful to Dr. T. Ichihashi and Prof. Y. Idemoto in Tokyo University of Science for TEM measurements. This study was partly funded by the MEXT program {"}ESICB{"} (JPMXP0112101003), the JST through A-Step program (AS282S001d), and JSPS KAKENHI (Grant No. 20H02849). The synchrotron radiation experiment was conducted with the approval of the Japan Synchrotron Radiation Research Institute (Proposal Nos. 2016A1536 and 2017B1585). Publisher Copyright: Copyright {\textcopyright} 2020 American Chemical Society.",
year = "2020",
month = sep,
day = "11",
doi = "10.1021/acsenergylett.0c01393",
language = "English",
volume = "5",
pages = "2849--2857",
journal = "ACS Energy Letters",
issn = "2380-8195",
publisher = "American Chemical Society",
number = "9",
}