Yet-Ming Chiang of the Massachusetts Institute of Technology, and colleagues, are researching and developing a new rechargeable battery that will hopefully compete with the current existing crop of batteries residing in electric cars to date.
Today’s electric cars contain batteries which are heavy, expensive and are a waste of space. Using Nissan’s leading car as an example. A car recognised globally and touted for its various awards such as, the 2010 Green Car Vision Award, the 2011 European Car of the Year award, and the 2011 World Car of the Year award [1]. And considered to be one of the most efficient vehicles ever due to the fact that it has the most efficient EPA ranking; it too also suffers from this inefficient battery inadequacy. Of course, the reason why that is, is simply that further developments are needed to improve and optimise the use of electric car batteries; so that they can be more competitive with other cars.
Nissan electric Leaf Battery, almost the entire floor of the car.
Electric car batteries to date, including the Leaf, consist of materials which provide mostly structural report but generate no power. The cost of the structural materials cost more than the electrically active components. Thus, one way in which these batteries could be improved upon is to make use of the deadweight and thus increase the efficiency of the whole battery.
This is where Chiang and his colleague’s developments come in. They are developing a battery which makes use of a black sludge nicknamed, “Cambridge crude (slurry)”. The slurry is to flow through an innovative architectural piece known as a semi-solid flow cell (SSFC) [2]. This slurry contains ions which hold the electrical charge of the battery.
One important characteristic of the new design is that it separates the two functions of the battery — storing energy until it is needed, and discharging that energy when it needs to be used — into separate physical structures. In conventional batteries, the storage and discharge both take place in the same structure. Separating these functions means that batteries can be designed more efficiently, Chiang says [3].
It is believed that the battery will be able to deliver 10 times more power, per unit volume, than conventional designs. Furthermore, cars would be able to travel at least 300 kilometres on a single charge, double what is possible with today’s batteries.
In addition, if it is to take off, drivers could also benefit from having up to three different methods of recharging their car battery. The first method consists of simply pumping out slurry and pumping in fresh slurry themselves. The second method is to go to a recharge station where tanks of slurry could be refreshed with new slurry. The final method would be to recharge the slurry with an electric current. In the first two cases regaining full power should only take a matter of minutes [4].
Due to the increased efficiency of the design and its ability to reduce the size and cost of the battery system i.e. getting rid of the deadweight the battery. Only then could it potentially compete with petrol, gas, or diesel vehicles. After all, if the SSFC batteries were to be of the same size as the current crop of batteries, they would have more electrically active components!
The potential of these batteries also paves away into other arenas of development. If the batteries were to be scaled up, to large sizes at low costs, they could also be suitable for large-scale electricity storage; for utilities. Intermittent, unpredictable sources such as wind and solar energy could be made more practical for powering the electric grid [3].
Yury Gogotsi, director of Drexel University’s Nanotechnology institute, says that the SSFC battery is a major breakthrough which shows that slurry-type active materials can be used effectively for storing electrical energy. Yet, he also stresses that despite its tremendous importance for future energy production and storage. Better cathode, anode, and electrolyte materials need to be found in order to make a practical, commercial version of the battery [3].
“I don’t see fundamental problems that cannot be addressed — those are primarily engineering issues. Of course, developing working systems that can compete with currently available batteries in terms of cost and performance may take years.”
Dan Steingart, City University of New York Energy Institute, refers to the technology as “beautiful”. He too adds some commentary to potential commercial development, although from a different approach. He says that even if the team manages to create a prototype car battery within five years, building the recharge stations to support it would take much longer [4].
Last year Chiang, his colleague Craig Carter and entrepreneur Throop Wilder founded a company called 24M Technologies to develop the battery [4]. The target of the team’s ongoing work, under a three-year ARPA-E grant awarded in September 2010, is to have, by the end of the grant period, “a fully-functioning, reduced-scale prototype system”; ready to be engineered for production as a replacement for existing electric-car batteries. Having raised $16 million in funding so far, and with 2013 coming soon just around the corner, perhaps we may soon see the commercial production of these batteries sooner than you think! From 2014 onwards, goodbye petrol, diesel and gas?
[1] http://en.wikipedia.org/wiki/Nissan_Leaf
[4] http://www.newscientist.com/article/mg21128246.500-black-gold-holds-a-charge-for-green-cars.html
