Korean researchers use laser ablation to create deformable micro supercapacitors

Recently, a research team from the Korea Institute of Industrial Technology and POSTECH University successfully utilized laser sintering pattern technology to create a deformable micro supercapacitor (MSCs), specifically designed to provide energy storage solutions for soft electronic devices.

This breakthrough meets the urgent need for efficient energy storage systems in stretchable devices in emerging health monitoring and other applications.
MSC provides customizable shape factors, reliable performance, effective space utilization, and easy integration with electronic components, making them a strong competitor to meet this demand. However, solid metals such as gold, which are commonly used to collect current in MSCs, have limited stretching ability and limit deformation potential.

In order to manufacture deformable micro supercapacitors (MSCs) that can bend and stretch without damaging or losing function, researchers chose a liquid metal - eutectic gallium indium alloy (EGaIn) as the current collector. EGaIn is highly deformable due to its high conductivity and liquid properties. However, how to utilize EGaIn to manufacture high-density digital inter mode to ensure high-energy storage performance has become a technical challenge.

Highly deformable micro supercapacitors (MSCs) are based on liquid metal current collectors. The researchers cleverly utilized laser ablation technology to achieve a perfect combination of high capacity and flexibility in micro supercapacitors (MSCs). They chose graphene as the electrode material and polystyrene block copolymer (SEBS) as the flexible substrate material. By uniformly laying EGaIn thin film on SEBS substrate through brush method and covering it with graphene, a digital graphene EGaIn electrode was finally created using laser ablation technology.

In optimizing the laser ablation process, researchers ensured complete ablation of graphene and EGaIn without damaging the SEBS substrate. Due to the ability of graphene and EGaIn films to absorb laser light at a wavelength of 355 nm, while SEBS materials do not absorb any light, the team successfully achieved selective ablation of graphene EGaIn electrodes without sacrificing the flexibility of SEBS substrates.

By finely controlling the gap between adjacent digital electrodes and graphene mass charges, researchers achieved a region capacitance of up to 1336 μ F cm-2 and demonstrated reliable rate performance. What's even more remarkable is that these MSCs can withstand up to 1000 stretching and contraction cycles without affecting energy storage performance.

To verify the practicality of MSC as a deformable power source, researchers constructed a soft electronic system consisting of a series and parallel MSC array integrated with LEDs. The system, relying on the liquid characteristics of the EGaIn current collector and the flexibility of the SEBS substrate, can operate stably under various mechanical deformations (such as folding, stretching, twisting, etc.), fully demonstrating its powerful energy storage performance.
Laser technology has played a crucial role in this research, enabling efficient application of liquid metals in MSC current collectors. Researcher Chanwoo Yang said, "Laser technology not only ensures the accuracy of work, but also accelerates the entire manufacturing process."

In addition, laser ablation technology is also suitable for patterning various electrode materials, including carbon materials, metal oxides, and Mxene, providing broad prospects for the development of deformable and high-performance energy storage systems.

With the rapid development of microelectronics and optoelectronics technology, miniaturized and elastic energy storage devices have become crucial, from folding and rolling equipment to stretching equipment in applications such as electronic textiles and healthcare. And this deformable MSC research based on laser ablation technology will undoubtedly provide strong support for the development and commercialization of elastic energy storage devices, and demonstrate enormous application value in multiple industrial fields.

Source: OFweek