title: Enhancing the energy density of safer Li-ion batteries by combining high-voltage lithium cobalt fluorophosphate cathodes and nanostructured titania anodes.
abstract: Recently, Li-ion batteries have been heavily scrutinized because of the apparent incompatibility between safety and high energy density. This work report a high voltage full battery made with TiO2/Li3PO4/Li2CoPO4F. The Li2CoPO4F cathode and TiO2 anode materials are synthesized by a sol-gel and anodization methods, respectively. X-ray diffraction (XRD) analysis confirmed that Li2CoPO4F is well-crystallized in orthorhombic crystal structure with Pnma space group. The Li3PO4-coated anode was successfully deposited as shown by the (011) lattice fringes of anatase TiO2 and (200) of γ-Li3PO4, as detected by HRTEM. The charge profile of Li2CoPO4F versus lithium shows a plateau at 5.0 V, revealing its importance as potentially high-voltage cathode and could perfectly fit with the plateau of anatase anode (1.8-1.9 V). The full cell made with TiO2/Li3PO4/Li2CoPO4F delivered an initial reversible capacity of 150 mA h g(-1) at C rate with good cyclic performance at an average potential of 3.1-3.2 V. Thus, the full cell provides an energy density of 472 W h kg(-1). This full battery behaves better than TiO2/Li2CoPO4F. The introduction of Li3PO4 as buffer layer is expected to help the cyclability of the electrodes as it allows a rapid Li-ion transport.
authors.affiliation: Inorganic Chemistry Laboratory, University of Córdoba, Marie Curie Building, Campus of Rabanales, E-14071 Córdoba, Spain.
authors.forename: Gregorio F
authors.initials: GF
authors.lastname: Ortiz
authors.affiliation: Inorganic Chemistry Laboratory, University of Córdoba, Marie Curie Building, Campus of Rabanales, E-14071 Córdoba, Spain.
authors.forename: María C
authors.initials: MC
authors.lastname: López
authors.affiliation: State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China.
authors.forename: Yixiao
authors.initials: Y
authors.lastname: Li
authors.affiliation: State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: McDonald
authors.affiliation: Inorganic Chemistry Laboratory, University of Córdoba, Marie Curie Building, Campus of Rabanales, E-14071 Córdoba, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Cabello
authors.affiliation: Inorganic Chemistry Laboratory, University of Córdoba, Marie Curie Building, Campus of Rabanales, E-14071 Córdoba, Spain.
authors.forename: José L
authors.initials: JL
authors.lastname: Tirado
authors.affiliation: State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Yang