Optimization of Carbon Nanotubes as Conductive Additives for High‐Energy‐Density Electrodes for Lithium‐Ion Batteries

Development of a high‐energy‐density electrode to use in lithium‐ion batteries (LIBs) is imperative for automotive applications. Although extensive efforts are put on developing high‐capacity cathode and anode materials for high‐energy‐density electrodes, challenging issues involving both the cathode and anode hinder practical application of the materials developed to date. Therefore, a practical approach to increase the energy density of LIBs is to design an electrode that has higher active material loading and a low fraction of nonactive materials. The present study demonstrates the use of carbon nanotubes (CNTs) as conductive additives for a high‐energy‐density electrode and reports the effect of the content of CNTs and binder on the slurry, electrode, and electrochemical performance of a cell. The electrochemical results and thermomechanical analysis reveal that the conductive network formed by CNTs and the binder plays a role in maintaining electrode integrity, thereby influencing cycle retention. Moreover, an electrode resistance analysis combined with electrochemical results shows that the ratio of CNTs and binder is a crucial factor in determining the rate capability. This understanding of the conductive network of CNTs/binder offers an insight into strategies to design high‐energy‐density LIBs.