Excess capacity on compound phases of Li_(2)FeTiO_(4) composite cathode materials synthesized by hydrothermal reaction using optional titanium sources to boost battery performance

摘要

Li_(2)FeTiO_(4) composites have been produced using commercial LiAC,FeCl_(2) and different titanium sources by hydrothermal synthesis(HS)at 175℃and subsequent annealing at 700℃.Impure phase TiO_(2),Fe_(2)O_(3) and FeTi0_(4) were detected out among the Li_(2)FeTiO_(4) composites with different titanium sources.Micron and nano-sized particles of Li2FeTiO4 were prepared from various titanium raw materials,with nano-sized particles predominating when titanium raw materials were layered hydrogen titanate nanowire(H2Ti3O7 NW,HTO-NW)and titanium oxide nanotubes(TiO_(2) NB).The Li_(2)FeTiO_(4) composites synthesized by HTO-NW shows a primary particle size of 50-200 nm of high crystallinity staggered with undissolved nanowire with a diameter size of about 100 nm.The samples using one-dimensio nal nanometer titanium oxide(TiO2 NB)as the raw material can get a super high initial discharge capacity of 367.8 mAh/g at the rate of C/10 and excellent cycling stability.The selection of raw materials and adopting multi-phase modification can be considered as an effective strategy to improve the electro-chemical properties of Li_(2)FeTiO_(4) composite cathode materials for the lithium secondary battery.