Perspective on the opportunities and future hurdles to realise structural supercapacitors
Topic(s) : Special Sessions
Co-authors :
Emile GREENHALGH (UNITED KINGDOM), Milo S. P. SHAFFER (UNITED KINGDOM), Sang NGUYEN , Anthony KUCERNAK (UNITED KINGDOM), Ajit PANESAR (UNITED KINGDOM), Emiliano BILOTTI , Shimeng QIAN (UNITED KINGDOM), Odysseas KAKARELIDIS (UNITED KINGDOM), Emily CHENG (UNITED KINGDOM), Elia CHIMONIDES (UNITED KINGDOM)Abstract :
Conventional structural composites have traditionally been adopted by engineers in applications in which lightweighting drives the product design. Consequently, over the last few decades, polymer composites have moved to the forefront of transportation applications, particularly aerospace. But with the drive to improve energy efficiency, new multifunctional materials in which added functions are imbued upon structural composites, are now emerging. The research community and industrial end-users have expressed particular interest in structural power composites: polymeric composites that not only carry mechanical load but are also imbued with the capacity to store and deliver electrical energy. Such materials will not only offer considerable mass and volume savings, but will also release engineering design constraints, offering exciting opportunities to innovate for future applications (see Figures).
To date, research in this field can be partitioned into structural batteries [1], which offer high energy densities but poor power densities, and structural supercapacitors [2], which offer high power density. The latter device offers an easier route to scale-up, hence providing the opportunity to investigate issues generic to structural power composites. However, there are several hurdles which need to be addressed to advance structural supercapacitors. These include development structural electrolytes that not only offer a competitive balance of mechanical and electrochemical performance but are also processable using conventional composite manufacturing techniques. Scale-up of structural supercapacitors is hindered by lack of solutions for efficient and light-weight current collection, as well as strategies for encapsulation that permit mechanical load transfer between the device and the surrounding conventional structure. Predictive modelling of structural supercapacitors is immature: advances are not only needed to complement and motivate research development but also to support certification of multifunctional products. Finally, perhaps the most pressing issue is that of characterisation and reporting protocols for structural supercapacitors. Such protocols are vital to motivate future research strategies and to candidly convey to industry the state-of-the-art performance of structural supercapacitors. This paper discusses these issues in detail and offers potential strategies to address them.
To date, research in this field can be partitioned into structural batteries [1], which offer high energy densities but poor power densities, and structural supercapacitors [2], which offer high power density. The latter device offers an easier route to scale-up, hence providing the opportunity to investigate issues generic to structural power composites. However, there are several hurdles which need to be addressed to advance structural supercapacitors. These include development structural electrolytes that not only offer a competitive balance of mechanical and electrochemical performance but are also processable using conventional composite manufacturing techniques. Scale-up of structural supercapacitors is hindered by lack of solutions for efficient and light-weight current collection, as well as strategies for encapsulation that permit mechanical load transfer between the device and the surrounding conventional structure. Predictive modelling of structural supercapacitors is immature: advances are not only needed to complement and motivate research development but also to support certification of multifunctional products. Finally, perhaps the most pressing issue is that of characterisation and reporting protocols for structural supercapacitors. Such protocols are vital to motivate future research strategies and to candidly convey to industry the state-of-the-art performance of structural supercapacitors. This paper discusses these issues in detail and offers potential strategies to address them.