Effect of particle-size distribution on LiFePO4 cathode electrochemical performance in Li-ion cells

LiFePO4 has structural and electrochemical advantages that make it an important candidate as a cathodic material. Its low cost, structural stability and low toxicity makes it a good option for energy backup systems. However, it is necessary to address the problem with its low ability to operate at high cycling speeds due its low electrical conductivity and low diffusion coefficient. In this work, the LiFePO4 powders were treated with ultrasound for different periods of time to study the effect of reducing the agglomerated particles in the wet mixture during the manufacturing stage. The samples were characterized by X-ray diffraction, scanning electron microscope, particle-size analysis and electrochemical methods. The results revealed that the ultrasonic treatment reduced the size particle of both active material and conductive additive improving the electrochemical behavior and specific capacity of the samples that were treated for longer periods of time.