Nav: Home

Fractional order modeling may reduce electric car drivers' anxiety

October 12, 2016

With rapidly diminishing fossil fuels, it's not impossible to imagine a future where most vehicles are powered completely by batteries. But to get there, scientists and engineers will have to solve a very important problem that affects drivers' peace of mind as well as their safety: Knowing just how much charge is left on their battery while driving. A branch of mathematics known as fractional order calculus may hold the answer. By suppressing the errors normally observed in methods for estimating charge, fractional order models could ultimately spell the difference between getting home safely and being stranded on the road.

It's virtually impossible to know exactly what goes on in a battery as it powers our phones, laptops, or cars. We can't crack open a battery without also killing power to our devices. And even if we could, there are complex chemical interactions, temperature effects and mechanical changes to consider. That's why researchers use more roundabout ways of estimating charge. These methods typically involve measuring external properties such as voltage or current to derive the charge. Each measurement, however, carries a small amount of error, and because many measurements are made every second, the errors quickly pile up. Although more advanced methods, such as Kalman filtering, use mathematical models to reduce these inaccuracies, they still produce errors of greater than 1%. The problem is that the underlying equations, which are based on integer order calculus, don't fully capture the complex electrochemical reactions that go on in a battery. These processes are better described with fractional order calculus. And by using this more exotic form, researchers developed a more accurate way of estimating the amount of charge left on a battery while it's in use.

First, the scientists took measurements of the battery's actual behavior while charging and discharging. Then, based on those measurements, they created a simple circuit model that replicated the battery's performance. Fractional order equations were then formulated to describe the activity of each element in the circuit. When researchers tested this model, they found that the estimated charge was much closer to reality than previously used methods: just half a percent off, compared to as much as 3 percent when using integer order calculus.

Although research on larger batteries is needed to further test the model, the initial results look promising. And one day, they could go a long way to reducing drivers' anxiety when they're on the road.
-end-
Fulltext of the paper is available: http://www.ieee-jas.org/EN/article/downloadArticleFile.do?attachType=PDF&id=154

http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=7508803

IEEE/CAA Journal of Automatica Sinica (JAS) is a joint publication of the Institute of Electrical and Electronics Engineers, Inc (IEEE) and the Chinese Association of Automation. JAS publishes papers on original theoretical and experimental research and development in all areas of automation. The coverage of JAS includes but is not limited to: Automatic control/Artificial intelligence and intelligent control/Systems theory and engineering/Pattern recognition and intelligent systems/Automation engineering and applications/Information processing and information systems/Network based automation/Robotics/Computer-aided technologies for automation systems/Sensing and measurement/Navigation, guidance, and control.

To learn more about JAS, please visit: http://ieeexplore.ieee.org/xpl/RecentIssue.jsp?punumber=6570654

http://www.ieee-jas.org

Chinese Association of Automation

Related Batteries Articles:

A seaweed derivative could be just what lithium-sulfur batteries need
Lithium-sulfur batteries have great potential as a low-cost, high-energy, energy source for both vehicle and grid applications.
Batteries from scrap metal
Chinese scientists have made good use of waste while finding an innovative solution to a technical problem by transforming rusty stainless steel mesh into electrodes with outstanding electrochemical properties that make them ideal for potassium-ion batteries.
Better cathode materials for lithium-sulphur-batteries
A team at the Helmholtz-Zentrum Berlin (HZB) has for the first time fabricated a nanomaterial made from nanoparticles of a titanium oxide compound (Ti4O7) that is characterized by an extremely large surface area, and tested it as a cathode material in lithium-sulphur batteries.
Bright future for self-charging batteries
Who hasn't lived through the frustrating experience of being without a phone after forgetting to recharge it?
Making batteries from waste glass bottles
Researchers at the University of California, Riverside's Bourns College of Engineering have used waste glass bottles and a low-cost chemical process to create nanosilicon anodes for high-performance lithium-ion batteries.
Batteries -- quick coatings
Scientists at Oak Ridge National Laboratory are using the precision of an electron beam to instantly adhere cathode coatings for lithium-ion batteries -- a leap in efficiency that saves energy, reduces production and capital costs, and eliminates the use of toxic solvents.
Lighter, more efficient, safer lithium-ion batteries
Researchers from Universidad Carlos III de Madrid and the Council for Scientific Research (initialed CSIC in Spanish) have patented a method for making new ceramic electrodes for lithium-ion batteries that are more efficient, cheaper, more resistant and safer than conventional batteries.
Clarifying how lithium ions ferry around in rechargeable batteries
IBS scientists observe the real-time ultrafast bonding of lithium ions with the solvents, in the same process that happens during charging and discharging of lithium batteries, and conclude that a new theory is needed.
A new approach to improving lithium-sulfur batteries
Researchers from the University of Delaware and China's Northwestern Polytechnical University, Shenzhen University and Hong Kong Polytechnic University have demonstrated a new polysulfide entrapping strategy that greatly improves the cycle stability of Li-S batteries.
Looking for the next leap in rechargeable batteries
USC researchers may have just found a solution for one of the biggest stumbling blocks to the next wave of rechargeable batteries -- small enough for cellphones and powerful enough for cars.

Related Batteries Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Anthropomorphic
Do animals grieve? Do they have language or consciousness? For a long time, scientists resisted the urge to look for human qualities in animals. This hour, TED speakers explore how that is changing. Guests include biological anthropologist Barbara King, dolphin researcher Denise Herzing, primatologist Frans de Waal, and ecologist Carl Safina.
Now Playing: Science for the People

#SB2 2019 Science Birthday Minisode: Mary Golda Ross
Our second annual Science Birthday is here, and this year we celebrate the wonderful Mary Golda Ross, born 9 August 1908. She died in 2008 at age 99, but left a lasting mark on the science of rocketry and space exploration as an early woman in engineering, and one of the first Native Americans in engineering. Join Rachelle and Bethany for this very special birthday minisode celebrating Mary and her achievements. Thanks to our Patreons who make this show possible! Read more about Mary G. Ross: Interview with Mary Ross on Lash Publications International, by Laurel Sheppard Meet Mary Golda...