Repairing the interfacial defect via preferable adsorption of ytterbium enables high-utilization and dendrite-free Zn metal anode

Abstract

Dendrite growth and spontaneous corrosion of zinc (Zn) metal anodes pose significant challenges for their application in grid-scale energy storage, primarily due to the instability of the bulk phase characterized by enriched defects. This study introduces ytterbium (Yb) as a strategic additive to fundamentally improve the stability of the anode. Specifically, Yb preferably accumulates in defect regions, restricting the non-uniform nucleation of Zn on grain boundaries and facilitating compact electrodeposition along the (002) planes, while significantly suppressing intergranular corrosion. Taking the above synergetic effects, the addition of Yb can significantly reinforce the cycle stability of the Zn anode. The symmetric cells exhibit superior reversibility for over 2400 hours under the current density of 1 mA cm−2. Additionally, it sustains an extended lifespan of 125 hours even at an ultrahigh Zn utilization of 80%. Furthermore, the CaV8O20xH2O|Zn full cells deliver excellent cycle stability, showing negligible capacity fading for 1000 cycles at a current density of 5 A g−1. Targeting the practicalization, the Ah-scale pouch cell exhibits reliable stability over 65 cycles. Therefore, incorporating Yb as an additive not only resolves critical performance challenges but also catalyzes the practical implementation of zinc batteries into large-scale energy storage systems.