title: Real-time observations of lithium battery reactions-operando neutron diffraction analysis during practical operation.
abstract: Among the energy storage devices for applications in electric vehicles and stationary uses, lithium batteries typically deliver high performance. However, there is still a missing link between the engineering developments for large-scale batteries and the fundamental science of each battery component. Elucidating reaction mechanisms under practical operation is crucial for future battery technology. Here, we report an operando diffraction technique that uses high-intensity neutrons to detect reactions in non-equilibrium states driven by high-current operation in commercial 18650 cells. The experimental system comprising a time-of-flight diffractometer with automated Rietveld analysis was developed to collect and analyse diffraction data produced by sequential charge and discharge processes. Furthermore, observations under high current drain revealed inhomogeneous reactions, a structural relaxation after discharge, and a shift in the lithium concentration ranges with cycling in the electrode matrix. The technique provides valuable information required for the development of advanced batteries.
authors.affiliation: Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8502, Japan.
authors.forename: Sou
authors.initials: S
authors.lastname: Taminato
authors.affiliation: Institute of Materials Structure Science, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan.|Sokendai (The Graduate University for Advanced Studies), Shirakata 203-1, Tokai, Naka 319-1106, Japan.
authors.forename: Masao
authors.initials: M
authors.lastname: Yonemura
authors.affiliation: Office of Society-Academia Collaboration for Innovation, Kyoto University, Uji-shi, Kyoto 611-0011, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Shiotani
authors.affiliation: Institute of Materials Structure Science, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan.|Sokendai (The Graduate University for Advanced Studies), Shirakata 203-1, Tokai, Naka 319-1106, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kamiyama
authors.affiliation: Institute of Materials Structure Science, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan.
authors.forename: Shuki
authors.initials: S
authors.lastname: Torii
authors.affiliation: Institute of Materials Structure Science, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan.
authors.forename: Miki
authors.initials: M
authors.lastname: Nagao
authors.affiliation: Institute of Materials Structure Science, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan.
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Ishikawa
authors.affiliation: Research Reactor Institute, Kyoto University, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Mori
authors.affiliation: Research Reactor Institute, Kyoto University, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan.
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Fukunaga
authors.affiliation: Research Reactor Institute, Kyoto University, Kumatori-cho, Sennan-gun, Osaka 590-0494, Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Onodera
authors.affiliation: Office of Society-Academia Collaboration for Innovation, Kyoto University, Uji-shi, Kyoto 611-0011, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Naka
authors.affiliation: Office of Society-Academia Collaboration for Innovation, Kyoto University, Uji-shi, Kyoto 611-0011, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Morishima
authors.affiliation: Office of Society-Academia Collaboration for Innovation, Kyoto University, Uji-shi, Kyoto 611-0011, Japan.
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Ukyo
authors.affiliation: Office of Society-Academia Collaboration for Innovation, Kyoto University, Uji-shi, Kyoto 611-0011, Japan.
authors.forename: Dyah Sulistyanintyas
authors.initials: DS
authors.lastname: Adipranoto
authors.affiliation: Office of Society-Academia Collaboration for Innovation, Kyoto University, Uji-shi, Kyoto 611-0011, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Arai
authors.affiliation: Graduate School of Human and Environmental Studies, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Uchimoto
authors.affiliation: Office of Society-Academia Collaboration for Innovation, Kyoto University, Uji-shi, Kyoto 611-0011, Japan.
authors.forename: Zempachi
authors.initials: Z
authors.lastname: Ogumi
authors.affiliation: Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8502, Japan.
authors.forename: Kota
authors.initials: K
authors.lastname: Suzuki
authors.affiliation: Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8502, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Hirayama
authors.affiliation: Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8502, Japan.
authors.forename: Ryoji
authors.initials: R
authors.lastname: Kanno