Micro-Architected Lithium Cobalt Oxide.

Area of Science:

• Materials Science
• Electrochemistry
• Additive Manufacturing

Background:

• Current additive manufacturing (AM) methods for battery electrodes, like extrusion-based direct ink-writing and vat photopolymerization (VP), have limitations in resolution and material choice.
• Existing techniques struggle to achieve fine feature sizes (150-200 µm) or require complex photoresin formulations for metal salt solutions.

Purpose of the Study:

• To introduce a new gel infusion AM technique for fabricating micro-architected battery cathodes with high resolution and material versatility.
• To demonstrate the capability of this method using lithium cobalt oxide (LCO) as a model cathode material.

Main Methods:

• Utilized VP 3D printing with a "blank" photoresin and a gel infusion process to create micro-architected electrodes.
• Fabricated free-standing, binder-free LCO electrodes with beam diameters below 50 µm.
• Characterized the microstructure, mechanical resilience (nanoindentation modulus 148.4–286.6 GPa), and electrochemical performance (reversible capacity 122–142 mAh g^-1).

Main Results:

• Achieved micro-architected LCO electrodes with tunable microstructure and mechanical resilience, free of grain boundary weakening.
• Demonstrated high reversible capacity (122–142 mAh g^-1) at a current density of 28 mA g^-1.
• The gel infusion AM technique offers micro-sized resolution (<50 µm beams) and adaptability for various cathode materials.

Conclusions:

• The gel infusion AM technique overcomes limitations of existing methods, enabling precise fabrication of micro-architected electrodes.
• This approach provides full control over electrode form factors, material selection, and microstructural features.
• Presents a promising pathway for developing next-generation energy storage devices with enhanced performance and tailored properties.