UNIST claims to have developed a stretchable rechargeable lithium-ion battery (ARLB) based on aqueous electrolytes, using the HCP composite as a stretchable current collector.
The demand of flexible electronics has driven the search for stretchable electrodes with high mechanical durability and high electrical conductivity during deformation. However, according to the research team, none of the methods proposed so far have managed to simultaneously achieve high stretchability for the electrodes and have a scalable manufacturing process.
Professor Soojin Park at School of Energy and Chemical Engineering, says he has solved this issue by using conductive polymer composite, composed of Jabuticaba-like hybrid carbon fillers containing carbon nanotubes and carbon black in a solution process.
The HCP composite is said to effectively retain its electrical conductivity, even under high strain rates, making it suitable for use in stretchable aqueous Li-ion batteries.
"Our findings are expected to expand the number of stretchable nanocomposites with electrochemical and mechanical properties available for use in a wide variety of applications," explains Professor Kwanyong Seo of UNIST.
Led by Professor So Youn Kim of UNIST, a detailed analysis of the percolation behaviours of the conductive filler within the composite was carried out using an in situ SAXS measurement under stretching. According to the team, the different types of carbon in the filler led to a formation of interconnected co-supporting networks.
The team says it has been able to deliver stable power to a LED even under 100% strain.
Professor Kim said: "This study is expected to facilitate the design of stretchable nanocomposites with optimised electrochemical and mechanical properties for use in energy storage devices and stretchable electronics.”
