Comparison of conductive additives for high-power applications of Li-ion batteries

Abstract

Carbon nanotubes, conductive poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) binder, conventional carbon black additives, and their mixes are compared with each other in terms of their effect on LiNi0.5Co0.2Mn0.3O2 slurries. The electrochemical characteristics of cathode slurries were studied using cyclic voltammetry, electrochemical impedance spectroscopy, and C-rate experiments in a half-cell configuration. Carbon nanotubes demonstrate the highest specific capacity 100 mAh/g at discharge currents 5–10 C in comparison with 60 mAh/g of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) binder and 40 mAh/g of Super P carbon black. The LiNi0.5Co0.2Mn0.5O2 electrode with carbon nanotubes showed 98.5% of the capacity retention after 100 cycles. A thorough comparison of three conductive additives demonstrates that carbon nanotubes are the most compatible and promising conductive additives for modern conventional manufacturing of high-power Li-ion batteries.