High-Reversibility Sulfur Anode for Advanced Aqueous Battery

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Sulfur is typically used as a cathode material in batteries.
• Developing efficient and stable anodes is crucial for next-generation batteries.
• Aqueous batteries offer safety and cost advantages over non-aqueous systems.

Purpose of the Study:

• To investigate sulfur as a low-potential anode in static aqueous sulfur-iodine (S-I2) batteries.
• To develop a novel membrane to suppress polysulfide shuttle effects.
• To evaluate the performance and advantages of the sulfur anode compared to traditional zinc anodes.

Main Methods:

• Fabrication of a highly reversible sulfur anode utilizing Na+ as the charge carrier.
• Development and implementation of a scalable sulfonated polysulfone (SPSF) membrane.
• Electrochemical testing including cycling stability, capacity retention, and comparison with Zn-I2 batteries.

Main Results:

• The sulfur anode demonstrated a low potential of -0.5 V (vs SHE) and a capacity of 1404 mA h g-1.
• The SPSF membrane effectively suppressed polysulfide/iodide shuttling, outperforming commercial Nafion in cost and environmental impact.
• The S-I2 battery with SPSF achieved 87.6% capacity retention over 500 cycles at 100% depth of discharge.

Conclusions:

• Sulfur can serve as a high-performance, reversible anode in aqueous batteries.
• The developed SPSF membrane is a cost-effective and environmentally friendly solution for shuttle effect mitigation.
• This work expands anode choices beyond metals for high-energy, low-cost, and fast-chargeable battery applications.