Inkjet-Printed Lithium-Sulfur Microcathodes for All-Printed, Integrated Nanomanufacturing

Area of Science:

• Materials Science
• Nanotechnology
• Electrochemistry

Background:

• The Internet of Things requires advanced energy storage for miniaturized devices.
• Current 3D microbatteries face limitations in energy density and complex fabrication.
• Lithium-ion chemistries present a fundamental barrier to microbattery miniaturization and cost-competitiveness.

Purpose of the Study:

• To develop inkjet-printed lithium-sulfur (Li-S) cathodes for integrated nanomanufacturing.
• To create thin-film microbatteries with high energy density and simplified fabrication.
• To explore novel materials and printing techniques for next-generation microenergy storage.

Main Methods:

• Utilizing single-wall carbon nanotubes infused with sulfur (S@SWNT) as an integrated current collector/active material composite.
• Employing inkjet printing for precise thin-film shape control and electrode dimensioning.
• Directly printing Li-S cathodes on semiconductor substrates (SiO2) or flexible aluminum foil.

Main Results:

• Achieved microelectrodes with a thickness of less than 10 µm.
• Demonstrated pseudocapacitive characteristics of S@SWNT with a solid-state discharge mechanism.
• Obtained initial capacities of approximately 800 mAh g⁻¹ S, retaining around 700 mAh g⁻¹ S after 100 cycles at C/2 rate.

Conclusions:

• Inkjet-printed Li-S cathodes represent a significant advancement in microbattery technology.
• The S@SWNT composite offers a promising material for high-performance, miniaturized energy storage.
• This approach facilitates cost-effective, integrated nanomanufacturing for Internet of Things devices.