Stencil-printed Li-ion batteries take any shape

August 26, 2016 // By Julien Happich
Using a simple stencil printing process followed by ultraviolet cross-linking, researchers from the Ulsan National Institute of Science and Technology (UNIST, South Korea) have demonstrated a new type of Printable Solid-State (PRISS) Lithium-ion batteries designed through successive layers of curable composite materials.

Published in ACS Nano Letters in a paper titled “Printable Solid-State Lithium-Ion Batteries: A New Route toward Shape-Conformable Power Sources with Aesthetic Versatility for Flexible Electronics”, the PRISS Batteries consist of a solid-state composite electrolyte (SCE) layer and SCE matrix-embedded electrodes, which can be printed on just about any object of any shape, as it is possible with today's stencil process.

Stencil printing of a conformable PRISS battery.

The researchers were able to tune the rheological properties of the SCE paste and electrode slurry to give them thixotropic fluid characteristics suitable for complex deposition patterns on non-flat objects. They also had to design a high boiling point electrolyte to make the PRISS batteries compatible with heat curing.

The materials used allowed the researchers to circumvent solvent-drying and liquid-electrolyte injection process steps, while removing the need for conventional microporous separator membranes. This makes the printable batteries truly shape-conformable, opening new design opportunities for better battery integration.