Electrochemically Dissociated Highly Compact Porous Carbon as a High-Capacity Capacitive Cathode for Lithium-Ion...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium-ion capacitors (LICs) show promise for large-scale energy storage.
• Performance is limited by mismatches between battery anodes and capacitive cathodes.
• Capacitive cathodes suffer from unsatisfactory charge storage capacity.

Purpose of the Study:

• To develop a novel capacitive cathode material for lithium-ion capacitors.
• To enhance the charge storage capacity of capacitive cathodes.
• To address performance limitations in current energy storage devices.

Main Methods:

• Electrochemical dissociation of graphene-based porous carbon using anion intercalation chemistry.
• In situ characterizations to observe anion intercalation and graphene sheet dissociation.
• Fabrication and testing of lithium-ion capacitors with the novel cathode material.

Main Results:

• Anion intercalation effectively dissociates stacked graphene nanosheets, boosting charge storage.
• The novel capacitive cathode achieves an ultrahigh specific capacity of 390 mA h g^-1.
• Performance significantly outperforms state-of-the-art capacitive and some battery-type materials.

Conclusions:

• The developed material represents a significant advancement for high-capacity capacitive cathodes.
• This work paves the way for more applicable and high-performance lithium-ion capacitors.
• Electrochemical anion intercalation is a viable strategy for enhancing carbon-based electrode materials.