Monolithic Nanoporous Zn Anode for Rechargeable Alkaline Batteries.

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Nanoporous zinc is crucial for enhancing electrical conductivity and surface area in alkaline batteries, extending the limited cycle life of zinc anodes.
• Traditional dealloying methods for fabricating nanoporous structures are limited by precursor material choices.

Purpose of the Study:

• To develop a novel method for fabricating monolithic nanoporous zinc.
• To overcome limitations of dealloying for creating rechargeable zinc anodes.
• To investigate the electrochemical stability and performance of the fabricated nanoporous zinc.

Main Methods:

• Utilized reduction-induced decomposition of zinc chloride (ZnCl2) using naphthalenide solution.
• Applied percolation dissolution mechanism to selectively dissolve chloride ions.
• Investigated electrochemical oxidation and reduction in alkaline electrolyte.

Main Results:

• Successfully fabricated a 200 μm thick monolith of nanoporous zinc with 70 nm wide percolating zinc ligaments.
• Observed surface-diffusion-controlled coarsening to a quasi-steady-state with a ∼500 nm length scale.
• Achieved 200 cycles of stable performance at 40% depth of discharge in a Nickel-Zinc battery.

Conclusions:

• The developed reduction-induced decomposition method offers a viable route to nanoporous zinc fabrication.
• The resulting nanoporous zinc structure demonstrates excellent stability and performance in alkaline electrolytes.
• This advancement holds promise for developing safer and more cost-effective energy storage solutions.