Synthesis of Mesoporous Ordered LiFePO4 /C Structures for Cathodes of Li-Ion Batteries

Tuesday, 7 October 2014
Expo Center, 1st Floor, Center and Right Foyers (Moon Palace Resort)
A. Y. Palacios Enriquez (Departamento de Química, Universidad Autónoma Metropolitana-Iztapalapa), J. Vazquez-Arenas, L. I. Vera-Robles (Universidad Autónoma Metropolitana-Iztapalapa, Departamento de Quìmica), and I. González (Universidad Autónoma Metropolitana-Iztapalapa. Departamento de Química)
The LiFePO4  phase has become a very promising cathode to be utilized in Li-ion batteries, as a result of its stability during intercalation, low toxicity, low cost and theoretical capacity of 170 mAhg-1. Unfortunately, this compound possesses low ionic and electronic conductivities resulting in a low performance of the battery. Different strategies have been proposed to improve the conductivity of the material (e.g. doping, mixing with carbon particles, finer particles). Recently, the development of a structured mesoporous LiFePO4/C has enabled to attain a larger specific capacity of 166 mAhg-1 and longer lifetime. However, the maximum capacities of this compound have not been investigated at all. Therefore, this study is oriented to improve the synthesis process of a structured mesoporous LiFePO4/C phase, in order to enhance the conduction and diffusion mechanisms. A structured mesoporous silica compound (SBA–15) is used as template for the fabrication of a mesoporous carbon structure, where the LiFePO4  phase is impregnated. This material is then compared (performance of the LiFePO4 in the battery) with that prepared using an alternative and faster synthesis route using activated carbon with large surface area.