Simultaneous Primer Coating for Fast Drying of Battery Electrodes

Abstract

Primers are used to promote adhesion and reduce electrical interface resistance. Normally, the process of applying primer and electrode coating happens in two separate, sequential steps. Herein, primer and electrode are applied simultaneously, wet-in-wet. For fast drying of electrode coatings, a binder-redistribution by binder migration happens. A normally unwanted binder migration is tried to be utilized. The goal is to use less binder in the electrode coating and dry it faster without losses in adhesion and performance. By using simultaneous primer coatings incorporating LAPONITE, the adhesion can be promoted by over 200%. This allows to eliminate the styrene-butadiene-rubber-binder in the electrode slurry, saving in total of 70% of the binder. For eight times faster drying up to 30% improved specific capacity at 2C can be shown. This promising approach shows potential for any materials that lack adhesion, extending it, e.g., to porous, nanostructured particles and materials used in sodium-ion batteries.