ABSTRACT: Rechargeable lithium metal batteries are considered the "holy grail" of energy storage systems. Unfortunately, uncontrollable dendritic lithium growth inherent in these batteries (upon repeated charge/discharge cycling) has pre-vented their practical application over the past 40 years. We show a novel mechanism which can fundamentally alter dendrite formation. At low concentrations, selected cations (such as cesium or rubidium) exhibit an effective reduction potential below the standard reduction potential of lithium ions. During lithium deposition, these additive cations form a positively-charged electrostatic shield around the initial growth tip of the protuberances without reduction and deposition of the additives. This forces further deposition of lithium to adjacent regions of the anode and eliminates dendrite formation in lithium-metal batteries. This strategy may also prevent dendrite growth in lithium-ion batteries as well as other metal batteries and transform the surface uniformity of coatings deposited in many general electrodeposition processes.
Journal of the American Chemical Society 02/2013; · 9.91 Impact Factor