New research published in Applied Physics Reviews from AIP Publishing considers the development of flexible supercapacitors (FSCs) that can be used in wearable electronics. There is serious interest in wearable electronics such as smart devices with embedded sensors and software that allow for the exchange of data with other devices, but flexibility is key to make such devices effective. The study comes from a team at Wuhan University and Hunan University that reviewed the energy storage of printed FSCs to assess their capacities to integrate with other devices.
"The development of miniaturized, flexible, and planar high-performance electrochemical energy storage devices is an urgent requirement to promote the rapid development of portable electronic devices in daily life," noted author Wu Wei. "We can imagine that in the future, we can use any printer in our lives and can print a super-capacitator to charge a mobile phone or smart wristband at any time."
Wu Wei’s team found that graphene and pseudocapacitive materials are examples of good core components for printed FCSs. They also determined that it is imperative to use as few ineffective additives as possible, as well as better conductive binders and high-quality dispersion electrode materials in order to make effective ink components. Furthermore, they conclude that it is important for inks to have good viscosity and rheology properties.
As Wu Wei implies, printed FSCs could replace conventional micromanufacturing techniques that are expensive and time-consuming. Printing electronics, on the other way, offers an economical, simple, and scalable strategy for manufacturing FSCs. This is because they are produced by printing functional inks on durable and flexible organic and inorganic electrode materials. Here, flexibility is imperative because it allows the printed products to be moved in a wide range of motions without losing electrochemical function.
In addition to easily integrating with other devices, printed FSCs are extremely low-cost, safe, and lightweight. They also have been shown to have high power density and fast charge and discharge rates. The team says they can be used in many diverse applications, for example in manufacturing solar cells, OLED displays, transistors, RFID tags, smart textiles, intelligent packaging, and smart labels.