Linear Matching Strategy of Cathode-Anode Capacity and Kinetics Enhances the Performance of Sodium-Ion Capacitors

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Sodium-ion capacitors (SICs) are promising energy storage devices.
• Kinetics mismatch between anodes and cathodes limits SIC performance.

Purpose of the Study:

• To demonstrate a capacity-kinetics linear matching strategy for enhanced SIC performance.
• To develop a novel slope-dominant carbon material for SIC anodes.

Main Methods:

• Fabrication of a novel slope-dominant carbon material (SC-O).
• Integration of SC-O anode with an activated carbon (AC) cathode.
• Performance evaluation of the fabricated SIC.

Main Results:

• SC-O anode exhibits high-capacity retention at high rates.
• Achieved linear capacity-kinetics matching between anode and cathode.
• Demonstrated remarkable energy density (81.3 Wh kg⁻¹ at 9891.2 W kg⁻¹) and ultralong lifespan (92.05% retention after 12,000 cycles).

Conclusions:

• The capacity-kinetics linear matching strategy is feasible for enhancing SIC performance.
• SC-O material provides a viable solution for high-rate/high-capacity battery-type anodes.
• This work guides the design of practical, high-power, long-cycle SICs.