Energy storage devices such as batteries and capacitors have become an integral part of our daily life and there is a tremendous zeal to accelerate this technology to be used in electric vehicles and grid storage. It also plays a vital role in mitigating climate change, and enables a low carbon economy by storing and utilising the energy generated from renewable resources. Although lithium ion batteries (LIBs) have dominated the market from 1990's, the shortage of resources and challenges faced in recycling LIBs which contain hazardous and reactive materials will have a detrimental effect on UK and make it dependent on external markets. Therefore, there is an urgent need to develop energy storage devices with environmentally benign and sustainable materials that are easy to recycle which would lead the way to a circular economy. In this regard, Zn ion capacitors (ZICs) offer a sustainable, cost-effective (cost-per-kWh) and safe energy storage system which is also easy to recycle.
Building on our previous work on using vitamin based ionic liquid electrolytes in batteries that are environmentally benign, the current project aims at developing Zn ion capacitors (ZICs) having high energy and power densities. This would lead ZICs to charge at a faster rate and store more energy. As an emerging topic, the major challenge in ZICs is the size and charge of Zn ions which are difficult to store at the cathode and leads to lower capacity and limited cyclability. Therefore, the project aims at
1. Developing suitable hybrid cathodes with 2D porous carbon embedded with transition metal oxides that can improve electronic conductivity and diffusion kinetics of Zn ions to obtain high power density, and also inducing storage sites in the cathode to obtain high energy density.
2. Understanding the Zn storage mechanism and impedimental reactions which take place in the capacitors by in situ measurement techniques in collaboration with Diamond Light Source.
3. Modulating the cathode to mitigate the impedimental reactions and improve the ZIC performance.
4. Engaging with project partners (TWI) for scale-up and implementation