Electrochemical impedance spectroscopy characterization of LiFePO4 cathode material with carboxymethylcellulose and poly-3,4- ethylendioxythiophene /polystyrene sulfonate

Новые электродные материалы для литий ионных батарей на основе литий феррофосфата и проводящего полимера были получены и исследованы. Показано существенное улучшение свойств материалов и обсуждены причины влияния полимера на функциональные свойства. Novel cathode material compositions based on lithium iron phosphate (LFP) were prepared using conducting polymer dispersion poly-3,4-ethylenedioxythiopene/polystyrene sulfonate (PEDOT:PSS) and water-based carboxymethylcellulose (E;E) as a binder solely and in mixture PEDOT:PSS/E;E. The electrochemical properties of materials in lithium-ion batteries were investigated by galvanostatic charge-discharge curves and by electrochemical impedance spectroscopy and the results were compared with conventional PVDF-bound material. Our best materials consisting of 92 wt% of C-LiFePO4, 4 wt% of carbon black and 4 wt% of conducting polymer binder exhibited excellent rate capability with discharge capacity 148 mAh g1 (at 0.2C, normalized by the electrode mass), 143 mAh g1 at 1