title: Electrochemical synthesis of a lithium-rich rock-salt-type oxide Li5W2O7 with reversible deintercalation properties.
abstract: Starting from the ribbon structure Li2W2O7, the lithium-rich phase Li5W2O7 with an ordered rock-salt-type structure has been synthesized, through a topotactic irreversible reaction, using both electrochemistry and soft chemistry. In contrast to Li2W2O7, the lithium-rich oxide Li5W2O7 shows reversible deintercalation properties of two lithium molecules per formula unit: a stable reversible capacity of 110 mAh/g at 1.70 V is maintained after 10 cycles. The exploration of the lithium mobility in this system shows that Li2W2O7 is a cationic conductor with σ = 4.10(-4) S/cm at 400 °C and Ea = 0.5 eV.
authors.affiliation: Laboratoire CRISMAT, CNRS ENSICAEN , 6 bd Maréchal Juin, 14050 Caen, France.
authors.forename: Valerie
authors.initials: V
authors.lastname: Pralong
authors.forename: Gopal
authors.initials: G
authors.lastname: Venkatesh
authors.forename: Sylvie
authors.initials: S
authors.lastname: Malo
authors.forename: Vincent
authors.initials: V
authors.lastname: Caignaert
authors.forename: Radu
authors.initials: R
authors.lastname: Baies
authors.forename: Bernard
authors.initials: B
authors.lastname: Raveau