The electrochemical performance of the high-energy Ni-rich NCM cathodes with Ni-content over 60% (LiNixCoyMnzO2 ; denoted as NCM622) with aqueous-based binders

Edel Sheridan, Artur Tron
Department of Sustainable Energy Technology, SINTEF Industry, 7491 Trondheim, Norway

The high potential cathode material of LiNixCoyMnzO2 (NCM) presents a higher reversible capacity with superior thermal stability, lower cost and less toxicity compared to LiCoO2 materials. While at use the aqueous-based binders can be improved their electrochemical performance due to a large extent, the high adhesion property as well as the highly homogeneous distribution of the electrode materials are the reasons for the excellent high rate and long-term cycling performance of the aqueous-based binder for NCM materials leading to the excellent electrochemical performance compared to the organic-based NCM materials (PVDF binder, polyvinylidene fluoride). Furthermore, applications of the aqueous-based binders can lead to the improvements of the performance of the binders which needs for the cathode materials operation and charged to high voltage (>4.5 V vs Li/Li+) to maintain surface stability of interface, prevent the undesirable interface side reactions leading to severe capacity fading for long-term cycling under a relatively high working temperature of LIBs. Therefore, in this work, it is studied the electrochemical performance of NCM material with Ni-content over 60% (NCM622) with the aqueous-based binder (Sodium carboxymethylcellulose ; denoted as CMC binder) and various type of additives. Compared with conventional organic-based NCM/PVDF electrodes, the aqueous-based NCM/CMC electrodes display the improvement of the electrochemical performance and successfully hinder the dissolution of the transition metal ions into the organic electrolytes leading to the enhance the cycling stability for long-term life and rate performance. Moreover, the use the aqueous-based NCM/CMC materials lead to prevent the corrosion of Al foil as the current collector and also reduce the cost issues and safety process the electrode preparation for lithium ion batteries for portable and large-scale applications.