Inhibition of Calendar Aging Induced Li Metal Corrosion Using Selected Area Insulating Layer Current Collectors

Li metal is a promising anode for next-generation batteries, but its high per-cycle capacity loss hinders its commercial adoption. A major contributor is the corrosion of Li during calendar aging, which accelerates the generation of degradation byproducts, such as the solid electrolyte interphase (SEI) and isolated Li (i-Li). Here, we reveal that Li corrosion is spatially heterogeneous: five times more capacity is lost at the edge overhang area of the current collector than at the center in the coin cell form factor. To address this, we developed a selected-area insulating layer (SAIL) that prevents Li plating in the overhang, yielding a 94% reduction in corrosion-induced capacity loss. Electron microscopy and titration gas chromatography were employed to visualize the morphological heterogeneity and quantify the disconnected Li loss at the center versus the overhang. Preventing dendritic Li plating in the overhang of the current collector can therefore substantially mitigate calendar aging-induced capacity loss.