A new bendable supercapacitor made from graphene has been developed and demonstrated by researchers from the UK’s University College London (UCL) and Chinese Academy of Sciences.
The proof-of-concept technology solves the key issue of supercapacitors by increasing both its power density and energy density— critical requirements for use in applications including electric vehicles.
Moreover, it can bend to 180 degrees (in a half-pipe configuration) without affecting performance and doesn’t use a liquid electrolyte.
The research was published in the journal Nature Energy on 17 February.
The scientists have reported the prototype reached 88.1Wh/L, and has a power density of more than over 10,000Wh/l and retained 97.8% of its capacity after 5,000 cycles.
Lead-acid batteries typically have 50-90Wh/L, whereas lithium-ion is at least double that number.
The electrodes are made from multiple layers of graphene that performs best when the pore sizes match the diameter of the ions in the electrolyte.
The 6cm x 6cm supercapacitor was made from two identical electrodes layered either side of a gel-like separator.
First author of the study, Dr Zhuangnan Li (UCL Chemistry), said they had designed their supercapacitor to increase power and energy density.
He said: “Normally, you can only have one of these characteristics but our supercapacitor provides both, which is a critical breakthrough.”
Senior author, professor Feng Li (Chinese Academy of Sciences), said: “By making energy storage smarter, devices will become invisible to us by working automatically and interactively with appliances. Our smart cells are a great example of how the user experience might be improved and they show enormous potential as portable power supply in future applications.”
The study was funded by the National Science Foundation of China, the Ministry of Science and Technology of China, the Chinese Academy of Science and the British The Engineering and Physical Sciences Research Council.