Development of New Synthesis Process of LiFePO4/C Composite

Abstract

: At the present time, our way of life has become completely dependent on energy. In order to solve the depletion of fossil fuels, an energy transition towards renewable energies such as solar energy, wind power, hydropower, geothermal power, bio energy, heat pump became inevitable. The development of such renewable but intermittent energy requires the development of energy storage solutions. Lithium ion (Li-ion) batteries had gained a lot of attention for powering portable electronic devices owing to its combination of high power and energy density, long cycle and stability. Current Li-ion battery technology consists of LiCoO2 and graphite as the cathode and anode materials, respectively. Nevertheless, LiCoO2 has a limited abundance in nature, toxic and very expensive. Its main drawback indeed is thermal instability leading to many safety issues. For this reason, LiFePO4 was presented as a potential candidate to replace LiCoO2, especially in the stationary applications LiFePO4 was first reported as positive electrode material for rechargeable Lithium batteries by Goodenough et al. in 1997. It shows a high theoretical capacity (170 mAh g-1), a high discharge potential (3.45 V Vs Li+/ Li), an excellent thermal stability, a low cost and it is environmentally friendly. Nevertheless, it has a poor ion diffusion coefficient (10-14 cm2 s-1) and low electrical conductivity (10-9 S cm-1). Carbon coating, reducing the particle sizes and doping with the conductive elements were the solutions suggested to overcome these drawbacks. This study aims to develop a scalable synthesis process of LiFePO4/ C composite starting from H3PO4 produced by OCP group. The electrochemical performances of various samples prepared by varying many synthesis parameters will be presented in this conference. Keywords: Li-ion batteries, LiFePO4, H3PO4, carbon coating. Acknowledgement: The financial assistance of the office Chérifien des Phosphates in the Moroccan Kingdom (OCP group): The authors are hereby acknowledged. Ms H. Aziam is grateful to Mohammed VI Polytechnic University for the scholarship.