Coherent Solid-Solution Interface With Near-Zero Lattice Mismatch Enables Stable Zinc Anodes

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Aqueous zinc-ion batteries (AZIBs) offer safe, low-cost, and high-capacity energy storage.
• Interfacial instability of zinc metal anodes, including dendrite formation and parasitic reactions, limits AZIB lifespan.
• Developing stable zinc anodes is crucial for advancing AZIB technology.

Purpose of the Study:

• To introduce a coherent solid-solution interface (SSI) strategy for stabilizing zinc metal anodes in AZIBs.
• To investigate the mechanism of interfacial stabilization using SSI with near-zero lattice mismatch.
• To demonstrate the enhanced electrochemical performance and long-term stability of AZIBs utilizing the SSI strategy.

Main Methods:

• In situ formation of a coherent solid-solution interface (SSI) with near-zero lattice mismatch (0.11%) to Zn.
• Experimental characterization and theoretical analysis of the Zn metal anode-SSI.
• Electrochemical testing of Zn||Zn symmetric cells, Zn||Cu asymmetric cells, and full cells (Zn||AC, Zn||I2, anode-free Zn||Br).

Main Results:

• The SSI effectively suppresses dendritic growth and parasitic reactions by enabling coherent Zn deposition.
• Zn||Zn symmetric cells achieved stable cycling for over 9100 hours.
• Full cells demonstrated exceptional cycle life (e.g., Zn||AC > 120,000 cycles) and high Coulombic efficiencies (up to 99.99%).
• Anode-free Zn||Br pouch cells achieved 61 Wh kg-1 energy density with 99.4% ACE.

Conclusions:

• Coherent interface engineering with near-zero lattice mismatch is a highly effective strategy for stabilizing zinc anodes.
• The SSI approach significantly enhances the cycle life and Coulombic efficiency of AZIBs.
• This work paves the way for developing high-energy, long-lifespan aqueous zinc-ion batteries.