Quasi-solid-state highly stretchable circular knitted MnO₂@CNT supercapacitor

Area of Science:

• Materials Science
• Electrochemistry
• Wearable Electronics

Background:

• Flexible and stretchable fiber supercapacitors are crucial for wearable electronics.
• Existing devices require improvements in stretchability and electrochemical stability during dynamic movement.

Purpose of the Study:

• To develop a quasi-solid-state circular knitted supercapacitor with enhanced tensile range and stable electrochemical performance.
• To investigate the potential of MnO2@CNT fiber supercapacitors for wearable energy storage applications.

Main Methods:

• Knitting carbon nanotube (CNT) fibers into a circular shape.
• Electrochemical deposition of manganese dioxide (MnO2) onto the knitted CNT fibers.
• Fabrication of double-walled supercapacitors by integrating knitted units.

Main Results:

• The knitted MnO2@CNT fiber supercapacitors demonstrated 100% structural stretchability.
• Stable energy storage performance was maintained during stretching up to 100%.
• High linear and area capacitance values were achieved (321.08 mF cm⁻¹ and 511.28 mF cm⁻²).
• Negligible capacitance loss was observed after 10,000 charge/discharge cycles and dynamic stretching tests.
• Double-walled supercapacitors also exhibited stable 100% stretchability without capacitance loss.

Conclusions:

• The developed knitted MnO2@CNT fiber supercapacitor offers a high tensile range and stable electrochemical performance.
• This technology is a promising candidate for energy storage solutions in wearable electronic devices.
• The design facilitates robust and reliable power sources for dynamic wearable applications.