Discovering the Intrinsic Causes of Dendrite Formation in Zinc Metal Anodes: Lattice Defects and Residual Stress

Developing a highly stable and dendrite-free zinc anode is essential to the commercial application of zinc metal batteries. However, the understanding of zinc dendrites formation mechanism is still insufficient. Herein, for the first time, we discover that the interfacial heterogeneous deposition induced by lattice defects and epitaxial growth limited by residual stress are intrinsic and critical causes for zinc dendrite formation. Therefore, an annealing reconstruction strategy was proposed to eliminate lattice defects and stresses in zinc crystals, which achieve dense epitaxial electrodeposition of zinc anode. The as-prepared annealed zinc anodes exhibit dendrite-free morphology and enhanced electrochemical cycling stability. This work first proves that lattice defects and residual stresses are also very important factors for epitaxial electrodeposition of zinc in addition to crystal orientation, which can provide a new mechanism for future researches on zinc anode modification.

Automated summary

Developing a stable and dendrite-free zinc anode is crucial for the commercialization of zinc metal batteries. However, the understanding of zinc dendrite formation mechanism is still insufficient. This study reveals that interfacial heterogeneous deposition induced by lattice defects and epitaxial growth limited by residual stress are intrinsic causes for zinc dendrite formation. An annealing reconstruction strategy is proposed to eliminate lattice defects and stresses, achieving dense epitaxial electrodeposition of zinc anode. The resulting annealed zinc anodes exhibit dendrite-free morphology and improved electrochemical cycling stability. This work provides a new mechanism for future research on zinc anode modification by highlighting the importance of lattice defects and residual stresses.