title: Towards High Capacity Li-ion Batteries Based on Silicon-Graphene Composite Anodes and Sub-micron V-doped LiFePO4Cathodes.
abstract: Lithium iron phosphate, LiFePO4(LFP) has demonstrated promising performance as a cathode material in lithium ion batteries (LIBs), by overcoming the rate performance issues from limited electronic conductivity. Nano-sized vanadium-doped LFP (V-LFP) was synthesized using a continuous hydrothermal process using supercritical water as a reagent. The atomic % of dopant determined the particle shape. 5 at. % gave mixed plate and rod-like morphology, showing optimal electrochemical performance and good rate properties vs. Li. Specific capacities of >160 mAh g-1were achieved. In order to increase the capacity of a full cell, V-LFP was cycled against an inexpensive micron-sized metallurgical grade Si-containing anode. This electrode was capable of reversible capacities of approximately 2000 mAh g-1for over150 cycles vs. Li, with improved performance resulting from the incorporation of few layer graphene (FLG) to enhance conductivity, tensile behaviour and thus, the composite stability. The cathode material synthesis and electrode formulation are scalable, inexpensive and are suitable for the fabrication of larger format cells suited to grid and transport applications.
authors.affiliation: Warwick University, Coventry, CV4 7AL, UK.
authors.forename: M J
authors.initials: MJ
authors.lastname: Loveridge
authors.affiliation: Warwick University, Coventry, CV4 7AL, UK.
authors.forename: M J
authors.initials: MJ
authors.lastname: Lain
authors.affiliation: University College, London, WC1E 6BT, UK.
authors.forename: I D
authors.initials: ID
authors.lastname: Johnson
authors.affiliation: Warwick University, Coventry, CV4 7AL, UK.
authors.forename: A
authors.initials: A
authors.lastname: Roberts
authors.affiliation: Warwick University, Coventry, CV4 7AL, UK.
authors.forename: S D
authors.initials: SD
authors.lastname: Beattie
authors.affiliation: Coventry University, Coventry, CV1 5FB, UK.
authors.forename: R
authors.initials: R
authors.lastname: Dashwood
authors.affiliation: University College, London, WC1E 6BT, UK.
authors.forename: J A
authors.initials: JA
authors.lastname: Darr
authors.affiliation: Warwick University, Coventry, CV4 7AL, UK.
authors.forename: R
authors.initials: R
authors.lastname: Bhagat