Printing guidelines for extrusion-based additive manufacturing with potential use in lithium-ion battery

Extrusion-based additive manufacturing significantly affects the performance of lithium-ion battery through structural heterogeneities, while there are no printing guidelines able to predict accuracy of printed features. Herein, an empirical model for geometric prediction is proposed and verified to fabricate 3D battery based on fundamental understanding of ink rheology and printing behavior. Lower viscosity of ink rheology is associated to the continuous phases homogeneously dispersed from lithium cobalt oxide and Super P, while adding more Super P induces lower shear rate due to higher viscosity resulted from the discontinuous phases of agglomerated Super P and voids under applied flow stress. Printing behavior enabling tunable line width relies on the synergistic interaction of ink rheology and processing condition, where controlling of the stretching region in thinning mode determines the printed line width under specific extrudate volume and moving speed. Furthermore, fluid dynamics combining with Darcy-Weisbach equation provides a model to predict the printing accuracy by calculating the flow rate and pressure drop, which exhibits a high consistency with experimental observations owing to the comprehensive consideration of various ink properties and printing parameters. This study provides systematic electrode printing guidelines for extrusion-based additive manufacturing, offering valuable insights for the development of high-performance lithium-ion batteries. • Systematic printing guidelines for manipulating printing geometry. • Ink rheology with moderate internal friction leads to smooth ink extrusion. • Synergy between ink property and printing conditions for high-quality printing. • Accurate parametric model for printing prediction.