Dendrite-Free Lithium Deposition via Self-Healing Electrostatic Shield Mechanism

TLDR

Rechargeable lithium metal batteries are hailed as the “Holy Grail” of energy storage, yet uncontrollable dendritic growth has thwarted their practical use for four decades. The authors present a novel mechanism that can fundamentally alter dendrite formation. By adding low‑concentration cations such as cesium or rubidium, whose reduction potential lies below that of lithium, a positively charged electrostatic shield forms around nascent lithium tips without the additives themselves reducing, thereby redirecting further deposition away from the tip. This approach forces lithium to deposit on adjacent anode regions, eliminating dendrite growth in lithium‑metal batteries and offering a potential solution for lithium‑ion and other metal batteries while improving coating uniformity in electrodeposition processes.

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 prevented their practical application over the past 40 years. We show a novel mechanism that can fundamentally alter dendrite formation. At low concentrations, selected cations (such as cesium or rubidium ions) 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.