Water-Based Process to the Preparation of Nickel-Rich Li(Ni <sub>0.8</sub> Co <sub>0.1</sub> Mn <sub>0.1</sub> )O <sub>2</sub> Cathode
Jia-He Kuo, Chia‐Chen Li
Abstract
Poly(acrylic acid) (PAA) is added as a binder to the water-based slurry of Ni-rich Li(Ni 0.8 Co 0.1 Mn 0.1 )O 2 (NCM811) powder. After adding PAA, the pH of the slurry changes from strongly alkaline to nearly neutral (pH9.0), making it suitable for casting on the aluminum current collector without corroding the aluminum (Al) and a largely increased adhesion from 318 to 458 kg m −2 after drying. The use of PAA also improves the dispersion of the slurry, because the carboxyl groups of PAA can interact with NCM811 to help stabilize the electrode particles in the slurry. Given the improved dispersion, reduced corrosion potential, and better adhesion, the resultant NCM811 cathode exhibits good structural integrity and greatly lowered charge-transfer resistance from 37.0 to 8.5 Ω, showing a high initial capacity of 189.2 mAh g −1 and capacity retention of 84.2% after 100 charge-discharge cycles under 0.2C.