High-Rate Charging of Zinc Anodes Achieved by Tuning Hydration Properties of Zinc Complexes in Water Confined within Nanopores

Abstract

Rechargeable batteries constructed with high-energy-density metal anodes, such as zinc and lithium, often suffer from dendrite formation during high-rate charging, which can lead to short circuits and reduced battery life. Here we report a novel method of realizing high-rate charging of zinc anodes together with the suppression of zinc dendrite formation by remarkably accelerating the electrodeposition within the nanopores of a porous electrode. By tuning not only the affinity between the wall-surface of nanopores and water but also that between the zinc complex with polyvalent carboxylates and water, we can establish a condition under which a surface-induced phase transition (SIFT) occurs. With the occurrence of SIFT, the penetration of zinc complexes into the nanopores becomes quite fast toward the formation of a second phase within the nanopore where the concentration of zinc complexes is orders of magnitude higher than in the bulk solution. More specifically, we use a hydrophobic nanoporous electrode,...