Properties of LiFePO4-based cathode material with additions of conducting polymer for Li–ion batteries

In this study, the electrochemical behavior and properties of the novel LiFePO4-based composite cathode material with a water-soluble binder LA-133 and a conductive polymer PEDOT:PSS (poly-3,4-ethylenedioxythiophene: polystyrenesulfonate) as an aqueous dispersion were studied. Using the conductive polymer in combination with a water-soluble binder LA-133 allows to reduce the proportion of electrochemically inactive components (up to 10\%) and thus to increase its specific capacity for a given weight of the active material. The capacity values for the most promising cathode material obtained were 146 mA h/g (at 0.2C) and 141 mA h/g (at 1C).
Key words: lithium iron phosphate, poly-3,4-ehthylenedioxythiophene, Li-ion batteries, charge-discharge curves.


1. Park K. S., Schougaard S. B., Goodenough J. B. Conducting-polymer / Iron-redox – couple composite cathodes for lithium secondary batteries. Adv. Mater., 2007, vol. 19, pp. 848–851, Doi:10.1002/adma.200600369.
2. Huang Y. H., Park K. S., Goodenough J. B. Improving lithium batteries by tethering carbon-coated LiFePO4 to polypyrrole. J. Electrochem. Soc., 2006, vol. 153, pp. A2282–A2286, doi:10.1149/1.2360769.
3. Huang Y. H., Goodenough J. B. High-rate LiFePO4 lithium rechargeable battery promoted by electrochemically active polymers. Chem. Mater., 2008, vol. 20, pp. 7237–7241, doi:10.1021/cm8012304.
4. Wang G. X., Yang L., Chen Y., Wang J. Z., Bewlay S., Liu H. K. An investigation of polypyrrole-LiFePO4 composite cathode materials for lithium-ion batteries. Electrochim. Acta, 2005, vol.50, pp. 4649–4654, doi:10.1016/j.electacta.2005.02.026.
5. Zhan L., Song Z., Zhang J., Tang J., Zhan H., Zhou Y., Zhan C. PEDOT : Cathode active material with high specific capacity in novel electrolyte system. Electrochim. Acta, 2008, vol. 53, pp. 8319–8323, doi:10.1016/j.electacta.2008.06.053.
6. Dinh H.-C., Mho S.-I., Yeo I.-H. Electrochemical analysis of conductive polymer-coated LiFePO4 nanocrystalline cathodes with controlled morphology. Electroanalysis, 2011, vol. 23, pp. 2079–2086, doi:10.1002/elan.201100222.
7. Vadivel Murugan A., Muraliganth T., Manthiram A. Rapid microwave-solvothermal synthesis of phospho-olivine nanorods and their coating with a mixed conducting polymer for lithium ion batteries. Electrochem. Commun., 2008, vol. 10, pp. 903–906, doi:10.1016/j.elecom.2008.04.004.
8. Trinh N. D., Saulnier M., Lepage D., Schougaard S. B. Conductive polymer film supporting LiFePO4 as composite cathode for lithium ion batteries. J. Power Sources, 2013, vol. 221, pp. 284–289, doi:10.1016/j.jpowsour.2012.08.006.
9. Cintora-Juarez D., Perez-Vicente C., Ahmad S., Tirado J. L. Improving the cycling performance of LiFePO4 cathode material by poly(3,4-ethylenedioxythiopene) coating. RSC Advances, 2014, vol. 4, pp. 26108–26114, doi:10.1039/C4RA05286B.
10. Das P. R., Komsiyska L., Osters O., Wittstock G. PEDOT : PSS as a functional binder for cathodes in lithium ion batteries. J. Electrochem. Soc., 2015, vol. 162, pp. A674–A678, doi:10.1149/2.0581504jes.
11. Vicente N., Haro M., Cíntora-Juárez D., Pérez-Vicente C., Tirado J. L., Ahmad S., Garcia-Belmonte G. LiFePO4 particle conductive composite strategies for improving cathode rate capability. Electrochim. Acta, 2015, vol. 163, pp. 323–329, doi:10.1016/j.electacta.2015.02.148.

стр. 39