title: Effect of nanostructured carbon coatings on the electrochemical performance of Li1.4Ni0.5Mn0.5O2+x-based cathode materials.
abstract: Nanocomposites of Li1.4Ni0.5Mn0.5O2+xand amorphous carbon were obtained by the pyrolysis of linear and cross-linked poly(vinyl alcohol) (PVA) in presence of Li1.4Ni0.5Mn0.5O2+x. In the case of linear PVA, the formation of nanostructured carbon coatings on Li1.4Ni0.5Mn0.5O2+xparticles is observed, while for cross-linked PVA islands of mesoporous carbon are located on the boundaries of Li1.4Ni0.5Mn0.5O2+xparticles. The presence of the carbon framework leads to a decrease of the polarization upon cycling and of the charge transfer resistance and to an increase in the apparent Li+diffusion coefficient from 10-16cm2·s-1(pure Li1.4Ni0.5Mn0.5O2+x) to 10-13cm2·s-1. The nanosized carbon coatings also reduce the deep electrochemical degradation of Li1.4Ni0.5Mn0.5O2+xduring electrochemical cycling. The nanocomposite obtained by the pyrolysis of linear PVA demonstrates higher values of the apparent lithium diffusion coefficient, a higher specific capacity and lower values of charge transfer resistance, which can be related to the more uniform carbon coatings and to the significant content of sp2-hybridized carbon detected by XPS and by Raman spectroscopy.
authors.affiliation: Department of Chemistry, M. V. Lomonosov Moscow State University, 119991 Moscow, Russia.
authors.forename: Konstantin A
authors.initials: KA
authors.lastname: Kurilenko
authors.affiliation: Department of Chemistry, M. V. Lomonosov Moscow State University, 119991 Moscow, Russia.
authors.forename: Oleg A
authors.initials: OA
authors.lastname: Shlyakhtin
authors.affiliation: Department of Chemistry, M. V. Lomonosov Moscow State University, 119991 Moscow, Russia; Department of Materials Sciences, M. V. Lomonosov Moscow State University, 119991 Moscow, Russia.
authors.forename: Oleg A
authors.initials: OA
authors.lastname: Brylev
authors.affiliation: Department of Chemistry, M. V. Lomonosov Moscow State University, 119991 Moscow, Russia; Department of Materials Sciences, M. V. Lomonosov Moscow State University, 119991 Moscow, Russia.
authors.forename: Dmitry I
authors.initials: DI
authors.lastname: Petukhov
authors.affiliation: Department of Chemistry, M. V. Lomonosov Moscow State University, 119991 Moscow, Russia; Department of Materials Sciences, M. V. Lomonosov Moscow State University, 119991 Moscow, Russia.
authors.forename: Alexey V
authors.initials: AV
authors.lastname: Garshev
keywords: Li-ion batteries; carbon coatings; electrode materials; nanocomposites; nanostructures