Throughout his career Associate Professor Scott Donne has undertaken significant research into energy storage. Lately, he has been developing a new supercapacitor that will potentially extend the lifetime of its many applications, from mobile phones to garbage trucks.
Can you please give a brief introduction to yourself and your background?
I’m a graduate of the University of Newcastle. I did my Bachelor of Science with Honours in chemistry here, as well as my PhD. In early 1996 I took a post doctoral fellowship at the University of California in Santa Barbara, in the US. The project I was working on was for the Eveready Battery Company, where I gained a great understanding of their technologies. After two years, I moved to Cleveland in the United States, which is where Eveready Battery Company has their international technology facility. I spent four years working there as a Technology Engineer, and while I was there I was partly responsible for the energizer e2 technology, as well as a lot of work developing their next generation technologies for batteries. In late 2001 I moved back to Newcastle to take up the Delta EMD Australia lectureship in applied chemistry.
Where do you think your interest in this area comes from?
I do find a lot of interest in the energy area. I really like physical chemistry, and energy storage is an aspect of that. At the time when I started there were some significant breakthroughs in energy storage research like batteries. So when I was just beginning my research career as an Honours student, there were opportunities with BHP and also with Australian Manganese Company as well, which was a spin-off from BHP at the time. I saw those opportunities and I took them.
What motivates you in your work?
Success. I think that’s a great motivator. Success comes in many forms, whether it’s having work published, securing a grant, or even just gaining a better understanding of a specific technology. I also like providing opportunities for students and I think working with students is a really big driving force for me as well. Currently my group consists of two post-docs and about 12 PhD students, and in each of their cases I’ve managed to make opportunities for them within the energy-related research area. It’s a great motivator to contribute to developing their skills, educating them, teaching them to be efficient researchers, and hopefully seeing them go off and be successful researchers themselves.
What do you consider to be your greatest success in your career so far?
There have been a few. One was being a part of the Energiser e2 technology development team, before I became an academic. Since becoming an academic, certainly the discovery of the supercapacitor technology has been quite substantial. Also working on the direct carbon fuel cell has been quite exciting.
You mentioned your work on supercapacitors; can you provide some more information on this technology?
Sure. Supercapacitors are energy storage technologies, but they function in a different role to batteries and fuel cells. Fuel cells operate in the space of high energy density but relatively low power density. That means that they can provide a lot of energy, but not at any great rate. A supercapacitor is at the other end of the spectrum, with low energy, but relatively high power density. I like think of it in terms of two cars at a set of traffic lights, one powered by a fuel cell, the other by a supercapacitor. When the lights turn green, the supercapacitor will take off like a rocket, and then stop the next block over because it will have run out of energy. The fuel cell car would take off slowly, but go on and on. A battery you will find somewhere in the middle of these two analogies.
There are different uses then for the different means of energy storage. What are some applications for supercapacitors?
There are many different applications that I can see it being used. Supercapacitors are very good at increasing the efficiency of other devices. For example it can be used in a modern cell phone that has a flash photographic capability. If there is a supercapacitor installed within the phone, you essentially extent the life of your battery and the phone.
There are also a lot of other applications that feature the ideal duty cycle for energy sources such as supercapacitors. That is, where there is a burst of power needed, followed by some downtime. On a larger scale, there have been discussions of a new kind of garbage truck that uses supercapacitors to be more efficient. The idea is that your average garbage truck with a diesel engine also has a bank of supercapacitors with an electric motor in there as a back-up for the engine. If you’ve ever seen a garbage truck go down the street, you’ll know that they stop at one house, collects the rubbish, and then the driver accelerates quickly for about 50 metres or so before he reaches the next house. For just a diesel engine that’s very inefficient, but for a supercapacitor, that’s perfect. Each time the driver accelerates, the supercapacitor can provide a burst of energy. During the few seconds that the driver brakes, the supercapacitor fully recharges and is ready to go again. Under these new circumstances the fuel efficiency of the garbage truck has been improved by about 45-50%, which is a really significant development in efficiency.
What sets your work on supercapacitors apart from others?
What we’ve done is made a pretty significant breakthrough in type of materials that you can use in a supercapacitor. Typical commercial materials these days are based on carbon that has very high surface area, but its specific capacitance is of the order of around 120 Farads per gram (F/g). What we’ve done is come along and made some electrodeposited metal oxides that have capacitances of the order of 2000 F/g, so we’re talking about a ten-fold increase in capacitance from these materials. That’s the breakthrough. What we’re trying to do now is work on making it a practical device.
What are some of the challenges you’ve faced while designing the supercapacitor?
It has some technical challenges. One is finding a suitable electrical substrate. Currently we use platinum, however platinum is not going to be used for any commercial devices because of its cost. So we’re looking at other suitable materials.The next greatest challenge is maintaining a funding stream, as well as getting the people to work on it. Those two go hand in hand.
How important is it for your work to have industry collaboration?
It’s very important. We have many collaborators, and their aim is to commercialise good research. So to be a part of that means there is more likely going to be an actual outcome for your work. I think it’s important to be working on something that will be of practical benefit within the foreseeable future.
What timeline do you think the supercapacitor is on in terms of commercialisation?
It’s still at the early stages at the present time. I have a couple of Honours students this year which is good because they’ll be committed full-time to various aspects of the technology. We’d like to see a device being manufactured within a few years.