title: Rock-salt-type lithium metal sulphides as novel positive-electrode materials.
abstract: One way of increasing the energy density of lithium-ion batteries is to use electrode materials that exhibit high capacities owing to multielectron processes. Here, we report two novel materials, Li2TiS3 and Li3NbS4, which were mechanochemically synthesised at room temperature. When used as positive-electrode materials, Li2TiS3 and Li3NbS4 charged and discharged with high capacities of 425 mA h g(-1) and 386 mA h g(-1), respectively. These capacities correspond to those resulting from 2.5- and 3.5-electron processes. The average discharge voltage was approximately 2.2 V. It should be possible to prepare a number of high-capacity materials on the basis of the concept used to prepare Li2TiS3 and Li3NbS4.
authors.affiliation: Research Institute for Ubiquitous Energy Devices, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Sakuda
authors.affiliation: Research Institute for Ubiquitous Energy Devices, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577, Japan.
authors.forename: Tomonari
authors.initials: T
authors.lastname: Takeuchi
authors.affiliation: Office of Society-Academia Collaboration for Innovation, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Okamura
authors.affiliation: Research Institute for Ubiquitous Energy Devices, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577, Japan.
authors.forename: Hironori
authors.initials: H
authors.lastname: Kobayashi
authors.affiliation: Research Institute for Ubiquitous Energy Devices, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577, Japan.
authors.forename: Hikari
authors.initials: H
authors.lastname: Sakaebe
authors.affiliation: Research Institute for Ubiquitous Energy Devices, National Institute of Advanced Industrial Science and Technology (AIST), 1-8-31 Midorigaoka, Ikeda, Osaka 563-8577, Japan.
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Tatsumi
authors.affiliation: Office of Society-Academia Collaboration for Innovation, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan.
authors.forename: Zempachi
authors.initials: Z
authors.lastname: Ogumi