Developing a sustainable, eco-friendly and flexible hybrid sodium ion capacitor
The use of sodium ions to form the fundamental layers of hybrid capacitors is one of the leading causes of reduced coulombic efficiency in batteries. The layer’s formation leads to premature failure and poor capacity retention. To address this problem, the EU-funded HybridFlex project intends to develop a sustainable, environmentally friendly and flexible hybrid sodium ion capacitor. To do this, it will integrate a flexible hard carbon battery-style anode and a flexible porous carbon supercapacitor-style cathode, electrospun from renewable lignin, into one energy storage device. The device will have higher energy density than flexible supercapacitors while also maintaining high cyclability and power density. The project’s work will further the rapid development of wearable electronics and sodium ion energy storage technology.