3D-Printed Micro-Supercapacitors Demonstrate Potential for Powering the IoT, Wearables, and More

Researchers from the Chinese Academy of Sciences and the University of Surrey have designed high-performance micro-supercapacitors which punch well above their weight — and that they say could power future Internet of Things (IoT), wearable, embedded, and implantable electronics with a microscopic footprint.

"This innovative microfabrication strategy marks a great advance as a new technological platform for monolithic micropower sources," claims study co-lead Zhong-Shuai Wu, professor at the Dalian Institute of Chemical Physics, of the work, "and will aid the applications where compact integration and high systemic performance is demanded from energy storage units."

The monolithic integrated micro-supercapacitors (MIMSC) designed by the team measure just 1.8mm² — meaning a large number of cells can be packed into a small surface area, helping to offset what the team admits is a merely "acceptable" volumetric energy density. When it comes to voltage, though, the team claims a record output for the area of the system — and an "unprecedentedly high" ability to retain its capacitance, with the prototype system still holding 92 per cent of its design charge after 4,000 cycles at a 162V output.

The secret to the team's success is a streamlined manufacturing approach, which helps improve uniformity between cells and stabilize electrochemical performance. The micro-supercapacitors are fabricated using multi-step lithographic patterning followed by spray-printing of MXene-based microelectrodes before being finished with 3D-printed gel electrolyte.

"Our strategy is expected to be applicable to other MIMSCs and integrated micro-batteries," the team concludes, "which could achieve high modular output capacities. Further architectural design (such as microelectrode configuration) is also possible to improve the space utilization of monolithic micropower sources for compact integration and high-systemic-performance-requiring applications."

The team's work has been published under open-access terms in the journal National Science Review.