On-chip UHD SS–MSCs as a device-unitized power source.
On-chip UHD SS–MSCs as a device-unitized power source.
Source: Professor Sang-Young Lee, UNIST

Tiny microsupercapacitor for wearable devices

A tiny microsupercapacitor (MSC) that is as small as the width of a person's fingerprint and can be integrated directly with an electronic chip has been developed. This has attracted major attention as a novel technology to lead the era of Internet of Things (IoT) since it can be driven independently when applied to individual electronic components.

Through the study, Professor Sang-Young Lee and his research team in the School of Energy and Chemical Engineering at UNIST have unveiled a new class of ultrahigh areal number density solid-state MSCs (UHD SS–MSCs) on a chip via electrohydrodynamic (EHD) jet printing. According to the research team, this is the first study to exploit EHD jet printing in the MSCs.

A supercapacitor (SC), also known as an ultracapacitor, can store much more energy than ordinary capacitors. The benefits of supercapacitors include having high power delivery and longer cycle life compared to lithium-based secondary batteries. In particular, it can be produced as small as the width of a person's fingerprint via semiconductor manufacturing process, and thus can be also applicable for wearables and Internet of Things (IoT) devices.

However, because the heat produced in manufacturing process may cause deterioration of the electrical characteristics of the supercapacitor, it has been difficult to connect them directly to electronic components. In addition, the fabrication method that combines supercapacitors with electronic components via inkjet printing technique has also the disadvantage of lower precision.

A tiny micro supercapacitor (MSC) as small as the width of a person’s...
A tiny micro supercapacitor (MSC) as small as the width of a person’s fingerprint.
Source: Professor Sang-Young Lee, UNIST

The research team solved this issue using EHD jet printing, a high-resolution patterning technique in microelectronics. EHD jet printing uses the electrode and electrolyte for printing purpose similar to that of conventional inkjet printing, yet it can control printed liquid with an electric field. "We were able to produce up to 54.9 unit cells per square centimeter (cm2) via electro-hydrodynamic jet printing technique, and thus the output of 65.9 volts (V) was achieved in the same area," says Kwonhyung Lee (Combined M.S/Ph.D. of Energy and Chemical Engineering, UNIST), the first author of the study.

The team also succeeded in fabricating 36 unit cells on a chip (area = 8.0 mm × 8.2 mm, 54.9 cells cm−2) and areal operating voltage (65.9 V cm−2) that lie far beyond those of previously reported MSCs fabricated by printing techniques. Besides, upon exposure to hot temperature (80 degrees C), these cells maintained normal cyclic voltammetry (CV) profiles, and thus has proven they can withstand excessive heat generated during the operation of actual electronic component. In addition, these batteries can provide customized powere supplies, as they can be connected either in series or parallel. "In this study, we have demonstrated on-chip UHD SS–MSCs fabricated via EHD jet printing," says Professor Lee. "The on-chip UHD SS–MSCs presented here hold great promise as a new platform technology for miniaturized monolithic power sources with customized design and tunable electrochemical properties."

Subscribe to our newsletter

Related articles

Printed electronics could charge out of thin air

Printed electronics could charge out of thin air

Researchers have developed a new approach to printed electronics which allows ultra-low power electronic devices that could recharge from ambient light or radiofrequency noise.

Your body is your internet – and now it can’t be hacked

Your body is your internet – and now it can’t be hacked

Researchers have built a device that could protect your pacemaker, other medical tech from remote hacks before they happen.

Graphene – the versatile wonder material

Graphene – the versatile wonder material

Graphene has a vast variety of practical applications in the creation of new materials. But what exactly is graphene and what makes it so special?

E-skin: recyclable alternative to wearables?

E-skin: recyclable alternative to wearables?

A wearable electronic device that’s 'really wearable” - a stretchy and fully-recyclable circuit board - can heal itself, much like real skin.

Step closer to high-performing wearable

Step closer to high-performing wearable

The University of Surrey has unveiled a device with unique functionality that could signal the dawn of a new design philosophy for electronics, including next-generation wearables and eco-disposable sensors.

Wearable sensor helps ALS patients communicate

Wearable sensor helps ALS patients communicate

Researchers have designed a skin-like device that can measure small facial movements in patients who have lost the ability to speak.

Powering wearable sensors through human motion

Powering wearable sensors through human motion

Researchers have harvested kinetic energy that is produced by a person as they move around.

Wearable pressure-sensitive devices

Wearable pressure-sensitive devices

Scientists have devised solutions to the problems presented in constructing wearable pressure-sensitive sensors.

3D printed transparent fibers can sense breath

3D printed transparent fibers can sense breath

Researchers used 3D printing techniques to make electronic fibres, each 100 times thinner than a human hair, creating sensors beyond the capabilities of conventional film-based devices.

Popular articles