Design of Continuous Kneading System for Active Anode Material Fabrication Using Retrofitted Assembly of Co-Rotating Screw Extruder

Abstract

As the demand for artificial graphite for lithium-ion battery (LIB) anode materials is on the rise, technologies for optimizing the manufacturing processes and reducing the production costs of artificial graphite are crucial. At the same time, globally, regulations on the generation of harmful volatile substances during the artificial graphite production process are also becoming increasingly stringent. In this study, we focused on a continuous kneading process that minimizes the emission of volatile substances during the manufacturing of artificial graphite. To this end, a carbonized material was first prepared from a mixture of needle coke and binder pitch and processed at 3200 °C using two types of co-rotating twin-screw extruder-based continuous kneading equipment to ultimately obtain artificial graphite. The physical properties of the carbonized as well as graphitized materials were analyzed, which revealed the superior performance of the LIB anode material, namely a discharge capacity of greater than or equal to 350 mAh/g, and an initial efficiency of 91% or higher. Thus, a continuous kneading manufacturing process that emits less harmful volatile substances and provides artificial graphite with sufficient battery performance was demonstrated.