Synthesis of LiTi2(PO4)3-acetylene black nanocomposites for lithium ion batteries by the polyvinyl alcohol assisted sol-gel method and ball-milling

Lithium titanium phosphate (LiTi2(PO4)(3)) has been successfully synthesized by a polyvinyl alcohol (PVA) assisted sol-gel method. To further improve its electrochemical properties, a ball-milling process with various amount of acetylene black (AB) has been used to form LiTi2(PO4)(3)-AB nanocomposites (the weight ratio of acetylene black is 5 wt.%, 10 wt.%, 15 wt.% and 20 wt.%). The samples are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Electrochemical performance of the samples is characterized by the charge-discharge test, cyclic voltammetry (CV), electrochemical impedance spectroscopic studies (EIS), and galvanostatic intermittent titration technique (GITT). The results show that the ball-milling process enables LiTi2(PO4)(3) nanoparticles to network with conductive acetylene black, which offers better electrochemical performance. Especially, LiTi2(PO4)(3)-AB nanocomposite with 15 wt.% acetylene black shows the best electrochemical properties, which delivers the highest specific capacity and the best cycle performance. Besides, the thermodynamics properties of as-prepared samples are also been studied. (c) 2013 Elsevier B.V. All rights reserved.