Na⁺/K⁺ Hybrid Battery Based on a Sulfurized Polyacrylonitrile Cathode

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Developing high-performance, cost-effective energy storage systems is crucial for modern technology.
• Rechargeable batteries utilizing abundant alkali metals like sodium and potassium are actively researched.
• Sulfurized polyacrylonitrile (SPAN) shows potential as an electrode material for advanced batteries.

Purpose of the Study:

• To synthesize sulfurized polyacrylonitrile (SPAN) nanocomposites.
• To construct and evaluate a novel rechargeable sodium-potassium (Na⁺/K⁺) hybrid battery using SPAN cathodes.
• To investigate the electrochemical performance and stability of the developed hybrid battery.

Main Methods:

• Synthesis of sulfurized polyacrylonitrile (SPAN) nanocomposites.
• Fabrication of a Na⁺/K⁺ hybrid battery with SPAN cathode, Na anode, and a hybrid electrolyte (NaPF₆/KPF₆ in EC/DMC/EMC).
• Electrochemical testing including cycling performance and coulombic efficiency measurements.

Main Results:

• A reversible capacity of 1405.5 mAh g_sulfur^-1 was achieved.
• Coulombic efficiency approached 100% after 100 cycles at 35 mA g^-1.
• The battery demonstrated suppressed dendrite formation due to a self-healing electrostatic shield effect.

Conclusions:

• The synthesized SPAN nanocomposites are effective cathode materials for high-performance Na⁺/K⁺ hybrid batteries.
• This environmentally benign and low-cost hybrid battery technology shows significant promise for flexible energy storage applications.
• The study highlights a novel approach to hybrid ion battery design utilizing synergistic Na⁺/K⁺ ion intercalation and conversion reactions.