Hybrid supercapacitors are novel, promising devices which strive to combine attractive features of both batteries (energy density) and supercapacitor (high rate performance). The concept of a lithium-ion capacitor has not yet become a commercial reality due to the limited storage capacity of the capacitor electrode. Sodium-based systems offer more versatile electrode chemistries while surprisingly maintaining equal or superior rate performance to lithium-ion systems, they also offer potential for lower cost and enhanced safety compared to lithium-ion. This cotutelle project will bring together the sodium-ion materials expertise in state-of-the-art electrodes at Coventry University with the knowledge and experience in advanced electrolytes at Deakin University.
This project and scholarship are offered as part of a collaborative doctoral cotutelle program with the Coventry University, UK. The successful candidate will be jointly supervised by a team of leading researchers from Deakin University and Coventry University and will graduate with a jointly supervised doctoral degree from each institution. The program is for a duration of 3.5 years. It is anticipated that the PhD candidate will spend at least 1 year during the program at Coventry University, with the remainder of the program based at Deakin University.
Deakin University has an extensive history of developing new ionic electrolytes based on ionic liquids, solids, and polymers for both lithium and sodium chemistries. Recent promising cell performances using hybrid organic-ionic solvents and their characterisation through NMR spectroscopy has opened the door to drastically improve the rate capability of ionic solvent-based electrolytes through considered materials design and understanding of the molecular interactions.
Coventry University has built a leading battery research program that is intimately engaged with sodium-ion battery industry partners in the EU and UK. Pilot-scale electrode production facilities along with sodium-ion battery expertise and knowledge of commercial electrode materials will see that this project brings together electrode and electrolyte systems that are at the leading edge of research and industry performance targets.
In this project, new electrolytes based on ionic-organic hybrid electrolytes will be explored for application in sodium-ion capacitor devices. These electrolytes retain the low volatility and safety of ionic electrolytes but gain rate performance advantages from the organic additive. Two variations of bis(fluorosulfonyl)imide (FSI) ionic liquids paired with either a tetra-alkylphosphonium or pyrrolidinium cation will be studied in a hybrid system containing traditional organic solvents such as carbonates or ethers and commercial sodium salts.
This requires developing an understanding of how the electrolyte chemistry can be tuned to promote fast sodium-ion transport through the bulk electrolyte, in addition to studying its impact on the disparate charge storage mechanisms occurring at a capacitive cathode (e.g. activated carbon) and a hard carbon anode. Electrochemical half and full coin cell cycling studies and electrode surface studies using traditional and advanced techniques based on electron microscopy, nuclear magnetic resonance spectroscopy, X-ray photoelectron spectroscopy, and glow-discharge optical emission spectroscopy (GDOES) will provide insights into the link between performance and materials behaviour during operation.
The interactions between electrolyte, separator, and binder will also be considered in order to allow for a direct comparison of optimised electrode/electrolyte systems.
Expressions of Interest to Deakin University and applications to Coventry University close 5 pm AEST, Monday 31 August 2020.
This scholarship is supported by Deakin University and is available for a duration of 3 years.
- Stipend of $28,092 per annum (2020 rate, indexed)
- 4 year tuition fee waiver
- Return economy airfare to Coventry University to support residency period in the UK
- Student visa and health insurance costs for period of residency at Coventry University in the UK
Coventry University will also provide a tuition fee waiver for the duration of the program.
To be eligible you must:
- be either a domestic or international candidate (domestic includes candidates with Australian Citizenship, Australian Permanent Residency or New Zealand Citizenship).
- meet the PhD entry requirements of both Deakin University and Coventry University, including English language proficiency requirements
- be enrolling full time
- be able to physically locate to both Coventry University (UK) and Deakin University (Australia)
How to apply
Applications are submitted to both institutions.
Shortlisted applicants will be interviewed by a panel of academic staff from each institution.
Please apply using the Expression of Interest Form, available via the ‘How to Apply – research degrees’ page, prior to being invited by the Faculty to lodge a formal HDR application to Deakin.
The successful candidate will also be required to lodge a separate PhD application to Coventry University via the Coventry ‘Making an Application page’.