Styrene-butadiene rubber patterned current collector for improved Li-ion kinetics of the anode for high energy density lithium-ion batteries

Abstract

The styrene-butadiene rubber (SBR) binder migration caused by the capillary force-driven solvent evaporation during the drying process results in the concentration gradient of SBR binder in the anode, which deteriorates the adhesion strength at the interface between the anode film and Cu current collector and Li-ion kinetics, respectively. Here, we report SBR patterned Cu current collector (SPC) to overcome problems caused by the SBR binder migration behavior. Pre-patterned SBR strongly adheres to the Cu current collector, which suppresses its migration during the drying process. Homogeneous SBR distribution in the longitudinal direction of the anode improves the adhesion strength and Li-ion kinetics. Enhanced adhesion strength enables the reduction of the SBR content in the anode, which further improves Li-ion kinetics. The anode employing SPC exhibits improved constant current charging capacity retention and cycling stability compared to those of the anode with a pristine Cu current collector.