Flexible, Stackable, and Fully Active Thick Electrode with Scalable 3D Topology Braid Structure Enables...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Thick electrode design is crucial for high energy/power density in energy storage devices.
• Achieving efficient ion and electron transport in thick electrodes remains a significant challenge.
• Current cost-effective methods for fabricating fully-active thick electrodes with continuous transport channels are limited.

Purpose of the Study:

• To develop a flexible, stackable, and fully-active thick electrode material for lithium-ion capacitors (LICs).
• To create a cost-effective method for fabricating electrodes with supercontinuous electron/ion transport channels.
• To investigate the performance and mechanism of the developed electrode in LICs.

Main Methods:

• Fabrication of a fully-microporous carbon cloth (FMCC) from cotton cloth using a facile strategy.
• Stacking multiple layers of FMCC to create a 3D topological network structure for thick electrodes.
• Assembly and electrochemical testing of LICs using FMCC as cathode and anode.

Main Results:

• The FMCC exhibits a fully microporous structure with a large specific surface area and self-supporting capability.
• The bi-directional woven hollow fiber bundle structure facilitates supercontinuous ion/electron transport.
• A 5-layer FMCC electrode achieved an ultrahigh area-specific capacity of 1.53 mA h cm⁻² at 1 A g⁻¹.
• A 4.9 V LIC assembled with thick FMCC electrodes demonstrated excellent energy/power density and stable performance under mechanical stress.

Conclusions:

• The developed FMCC is a promising material for high-performance, flexible thick electrodes in LICs.
• The 3D topological network structure and inherent microporosity are key to achieving superior electrochemical performance.
• This work provides valuable insights for designing advanced flexible energy storage devices.