Electrophoretic deposition of LiFePO4 for Li-ion batteries

An electrophoretic deposition (EPD) method has been developed for the deposition of LiFePO4-carbon black films for application in Li-ion batteries. The approach is based on the use of poly[1-[4-(3-carboxy-4-hydroxyphenylazo)benzenesulfonamido]-1,2-ethanediyl, sodium salt] (PAZO-Na) and carboxymethyl cellulose sodium salt (CMC-Na), as dispersing, charging and film forming agents. The individual monomers of PAZO-Na and CMC-Na created multiple bonds with metal atoms on the particle surface and allowed for efficient electrosteric dispersion and charging of relatively large commercial LiFePO4 particles. The microstructure, deposition mechanism and electrochemical performance were investigated. The LiFePO4 electrode, prepared by the EPD method, exhibited a capacity of 146.7 mA h g−1 at C/10 and enhanced cycling stability.