Synt hesis and Characte rization of LiFePO۴ Nanoparticles via Hydrothe rmal Method

Phosphates LiMPO۴ (M = Mn , Fe, Co, or Ni) have b een investigated intensi vely as prom ising cathod e materials for lithium batteries. [۱]Among several m aterials under develop ment for use as cathodes in lithium-ion batteries, LiFePO۴ appears to be a pro mising candidate beca use of its high theoreti cal capacity (۱۷۰ mAh gí۱), low c ost, excelle nt cycling stability, low toxicity, and enviro nmentally benign nature.[۲] LiFePO ۴ has a hi ghly stable three-dimen sional fram ework due to strong P Ocovale nt bonds in (PO۴)۳í polyanion, which proh ibits the liberation o f oxygen. These charac teristics provide an excellent safety under abus e conditions of the batteries. LiFePO ۴ can be syn thesized using conventional solid-state reactions. However, it is difficult to attain its full capacity, because its electronic conductivity is very lo w, and diff usion of Li+ ion in the olivine struct ure is slow. Several alter native synt hetic method s have been applied to the preparat ion of LiFePO۴. In addition, highly dispersed co nductive substances such as carbo naceous materials and so me metals in the cathode composite electrode w ere reporte d as being ef ficient additives. The h ydrothermal synthesis is a useful method for preparing fi ne particles. It also has other advantages such as a simple process and e nergy efficient.In this study LiFePO۴ was hydrothermall y synthesized at slightly basic and n eutral conditions by add ing a little amount of su crose as a reducing agent.

کلیدواژه ها:

LiFe PO۴ ، Hydrothermal method ، Li thium ion batteries ، C athod Mat erials ، Nanop articles