Longer-Lasting Lithium-Sulfur Batteries Developed For Use In EVs

April 3rd, 2013 by James Ayre

Reposted from EV Obsession:

A new lithium-sulfur battery design has been created that improves the charge cycles of lithium-sulfur batteries by a factor of seven. This significant improvement in technology means that perhaps in the near future, lithium-sulfur batteries, which are considerably more cost-effective that lithium-ion batteries, will become a viable choice for use in electric vehicles. The new design was made by researchers at the Fraunhofer Institute for Material and Beam Technology IWS in Dresden.

Image Credit: © Jürgen Leibmann

“During previous tests, the batteries scarcely crossed the 200-cycle mark. By means of a special combination of anode and cathode material, we have now managed to extend the lifespan of lithium-sulfur button cells to 1,400 cycles,” says Dr. Holger Althues, head of the Chemical Surface Technology group at Fraunhofer IWS.

The primary issue with lithium-sulfur batteries that the new design addresses is that the sulfur cathode interacts too much with the liquid electrolyte, over time limiting performance and eventually causing the battery to stop working altogether. In the new design, this is addressed through the use of “porous carbons” that slow down the process.

“We have precisely altered the pores to allow the sulfur to lodge there, slowing down the rate at which it combines with the electrolyte,” states Althues. The researchers have also developed a method to manufacture these specialized cathodes.

Eventually, according to the researchers, lithium-sulfur batteries will reach energy densities much higher than those possible in lithium-ion batteries, up to more than two times higher. “In the medium term, figures around the 500 Wh/kg mark are more realistic. In practical terms, this means you can drive twice as far with the same battery weight,” says Althues. “This of course implies that significantly lighter battery models are possible — an interesting prospect not only for automakers but for smartphone manufacturers too. After all, the overall weight of smartphones would be greatly reduced if they had lighter batteries.”

That all sounds great, but here’s my favorite part: “Lithium-sulfur technology might even make electric flying a realistic possibility. Although such progress is still a long way off,” says Althues.

An electric aircraft, similar to modern commercial airplanes, but powered entirely by electricity, is a very appealing thought.

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Tags: EV battery improvements, Fraunhofer Institute, Fraunhofer Institute for Material and Beam Technology, Fraunhofer Institute for Material and Beam Technology IWS in Dresden, Fraunhofer institute lithium sulfur, linger lasting lithium sulfur battery, Lithium ion batteries replacements, Lithium-Sulfur Batteries, long lasting lithium sulfur batteries, no post

About the Author

James Ayre 's background is predominantly in geopolitics and history, but he has an obsessive interest in pretty much everything. After an early life spent in the Imperial Free City of Dortmund, James followed the river Ruhr to Cofbuokheim, where he attended the University of Astnide. And where he also briefly considered entering the coal mining business. He currently writes for a living, on a broad variety of subjects, ranging from science, to politics, to military history, to renewable energy. You can follow his work on Google+.

http://www.facebook.com/people/Bruce-Miller/100000952005408 Bruce Miller

Higher voltages for nano carbon super capacitors will yield the higher and desired power density?” For a moment: a ten fold voltage increase on current super caps would do the job? and with zero internal resistance as found in batteries? Gasoline engines hardly approach 25% efficiency today?
Cowboyleland

The Solar Impulse plane has been flying since 2010. Its captain is even named Picard. The posibility is closer than you think.
anderlan

Ah, dreaming about dense batteries.

Fun figures:
Equivalent power level of a gas pump filling your car: 1MW
Highest power charger (Tesla proprietary): 90kW (0.09MW)
Energy density of gasoline: 10kWh/kg.
Energy density of Tesla pack: 132Wh/kg (0.132kWh/kg)

Those are the targets, folks. Heh, just 2 orders of magnitude for both charging and density. Call me a techie dreamer, but I think they could fall before I get too elderly. We’re talking about nano structures and electronics. How long does it take an IT resource to become 100 times better? 20 years? The question is, do we want the targets to fall, or do we want to keep things the way they are? It’s a lot of work to do yet. We ought to be pushing with all we can.
- Kevin Adams
  
  I think you gasoline figure is a little high. Did you account for the heat losses? When compared to an electric battery a gallon of gasoline (roughly 4.5 liters) weighs approximately 6 pounds
  (just less than 3 kilograms), occupies a mere 230 cubic inches but contains the
  equivalent of 36 kWhs of electrical energy. That would be closer to 12,000Wh/kg for gasoline (which is just under 2 orders of magnitude higher than the Tesla pack)
  - http://www.facebook.com/people/Bruce-Miller/100000952005408 Bruce Miller
    
    The battery pack or super-capacitor bank in my electric can take all the space and weight left over from the gasoline power train. My electric car will have hub drive motors on 30″+ rims? The whole area under the hood will be empty? or filled with power storage?
    - Kevin Adams
      
      Tesla is using that area for a frunk (a front trunk), it is pretty sweet.
  - anderlan
    
    You’re totally right. I had the gasoline kwh/kg correct, then I looked at it again and for some reason set 1 gallon = 1 pound instead of 8 pounds. Fixed it back the way it was just now. Thanks. 10kwh/kg is way less than 74kwh/kg.
- http://www.facebook.com/people/Jouni-Valkonen/736198505 Jouni Valkonen
  
  Electric cars can be recharged, when they are parked. With gasoline engine you need to waste 15 minutes of your life every time you are going to refill at gas station.
  - anderlan
    
    You’re absolutely right. EVs are *already* a better proposition than gasoline. They don’t have to even approach those gasoline numbers. It’s just fun to see how close we are and to think about how incredible better the world might soon become.
  - http://zacharyshahan.com/ Zachary Shahan
    
    possibly the most underrated benefit of electric cars.