Ultrahigh-Mass-Loading Electrodes With Enhanced Homogeneity Using a High-Concentration Slurry for Lithium-Ion Batteries

Abstract

Strategies for achieving high-energy-density lithium-ion batteries include using high-capacity materials such as high-nickel NCM, increasing the active material content in the electrode by utilizing high-conductivity carbon nanotubes (CNT) conductive materials, and electrode thickening. However, these methods are still limited due to the limitation in the capacity of high-nickel NCM, aggregation of CNT conductive materials, and nonuniform material distribution of thick-film electrodes, which ultimately damage the mechanical and electrical integrity of the electrode, leading to a decrease in electrochemical performance. Here, we present an integrated binder-CNT composite dispersion solution to realize a high-solids-content (> 77 wt%) slurry for high-mass-loading electrodes and to mitigate the migration of binder and conductive additives. Indeed, the approach reduces solvent usage by approximately 30% and ensures uniform conductive additive-binder domain distribution during electrode manufacturing, resulting in improved coating quality and adhesive strength for high-mass-loading electrodes (> 12 mAh cm−2). In terms of various electrode properties, the presented electrode showed low resistance and excellent electrochemical properties despite the low CNT contents of 0.6 wt% compared to the pristine-applied electrode with 0.85 wt% CNT contents. Moreover, our strategy enables faster drying, which increases the coating speed, thereby offering potential energy savings and supporting carbon neutrality in wet-based electrode manufacturing processes.