Wood-Inspired High-Performance Ultrathick Bulk Battery Electrodes

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Ultrathick electrodes boost lithium-ion battery (LIB) specific energy without altering material chemistry.
• Random microstructures in current ultrathick electrodes impede Li-ion conductivity, reducing rate performance.

Purpose of the Study:

• To develop ultrathick LIB electrodes with high areal capacity and excellent rate capability.
• To mimic natural hierarchical structures for improved ion transport in LIBs.

Main Methods:

• Utilized a sol-gel process to template wood microstructures into bulk LiCoO2 (LCO) cathodes.
• Employed X-ray-based microtomography to analyze electrode microstructure and tortuosity.

Main Results:

• Wood-templated LCO cathodes exhibited uniform microchannels, reducing tortuosity by 1.5 times and increasing Li-ion conductivity twofold compared to random structures.
• Achieved a high areal capacity of 22.7 mAh cm-2, five times greater than conventional electrodes.
• Successfully demonstrated dynamic stress testing at this high areal capacity.

Conclusions:

• The wood-inspired design effectively enhances Li-ion transport and energy density in ultrathick LIB electrodes.
• This approach offers a new strategy for utilizing natural hierarchical structures to advance LIB performance.