
MIT students develop liquid fuel for electric cars - jamesjyu
http://i.autoblog.com/2011/06/08/mit-students-develop-liquid-fuel-for-electric-cars/
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jws
The highest energy density listed for the electrolytes on the wikipedia page
for flow batteries is 75 watt hours/kg, that is about 0.25Mj/kg. Gasoline is
42Mj/kg.

The original MIT release claims a 10 fold improvement in energy densities over
existing flow batteries, but that is still more than an order of magnitude
worse than the incumbent fuel.

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colomon
Isn't that about the level where it gets interesting? My car can go something
over 400 miles on a tank of gas right now. If their new batteries can get 40
miles on a "tank", and be refueled as easily as my car can now, that seems
right on the threshold of being a very viable product.

~~~
jamesaguilar
Also, gas tanks could be a lot bigger without ruining cars. Things would be
slightly less efficient, but if the solution is just being reused then pumping
thirty gallons at once might not be the end of the world (as opposed to the
ten that currently fit in my tank). If the solution weighs as much as
gasoline, then that's an extra 120 lbs when the tank is full, which is a lot,
but it's <5% extra.

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sliverstorm
Not to mention if the tank is full of a fluid that is not particularly
dangerous, you might be able to integrate it into the structure of the car,
similar to motorcycles with oil-in-frame design.

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ender7
Original article: <http://web.mit.edu/newsoffice/2011/flow-
batteries-0606.html>

~~~
tjmc
Original paper:
[http://onlinelibrary.wiley.com/doi/10.1002/aenm.201100152/ab...](http://onlinelibrary.wiley.com/doi/10.1002/aenm.201100152/abstract;jsessionid=8AE6EDCECE055B97EB99CF4483EC426C.d01t02)
(free access until 27 June 2011)

This looks like a major breakthrough. Love the nickname - "Cambridge crude".
As with all flow batteries, power density is low. But you could possibly
compensate for that in vehicles with ultracapacitors which could also
recapture energy from braking.

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tansey
Worth noting that the liquid is rechargeable/reusable:
<http://en.wikipedia.org/wiki/Flow_batteries>

According to the Wikipedia page, the main issue with these batteries is low
energy density. If this group has figured it out, they may be on to something
huge.

~~~
artmageddon
I agree, if a development like this were to happen for electric vehicles,
adoption of them would skyrocket. The one thought I have is how much will this
cost to produce initially per liter, as well as over time when it reaches a
critical mass?

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ovi256
As I've learned when such promising technology is announced, I'll wait for
system integration prototypes to roll out.

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hugh3
Often in these sorts of articles, you can tell what the _big_ problems are by
the fact that they're not even mentioned. The big unmentioned problems here
seem to be:

a) Cost

b) Cost

c) Safety, and

d) Cost

I'm not sure what materials they're making these things from, but would it be
fair to guess that it's something exotic and hard to fabricate?

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bellaire
From the article: "The tech supposedly makes the batteries up to ten times
more efficient than their traditional counterparts, and even more importantly,
the new tech is cheaper to produce."

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MichaelApproved
Cheaper is meaningless in this context. For example, if the traditional
counterparts cost $1,000/mile then $100/mile is still cheaper but still far
from being pratical. We have no idea what it's cheaper than and by how much
it's cheaper by.

Of course, my numbers are completely made. It's just meant as an example.

~~~
invisible
I'm pretty sure it is saying 10x better and cheaper than a standard lithium
ion for the same battery size. If they are not saying that then the sentence
makes no sense.

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stretchwithme
When a major change is made to how something is done, there really needs to be
a very significant improvement that makes the cost of changing worthwhile.

I think eventually this will happen with electric vehicles, but no one knows
for sure. Which is probably why we shouldn't subsidize solutions that are not
compelling enough. The current electric vehicles aren't even as good as what
they are attempting to replace and wouldn't be available at all without the
massive subsidies.

If we do subsidize things in an effort to "jumpstart" the change, we might
actually switch to a system that is not compelling enough and might get
persuaded to jumpstart the next generation, which might have been compelling
enough on its own. And be stuck with the cost of the subsidies or paying the
higher cost directly.

Of course, such changes become so monolithic to begin with when government
picks a standard and encourages everyone to adopt it. It may drive down costs
in the short run, but it reduces progress in the long run.

For example, the adoption of the NTSC tv format and enforcing it using the
FCC. We got color. Then we got closed captioning. And that was probably all
the innovation we got over 50 years. But look at how quickly video has evolved
on personal computers by comparison.

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kmod
"liquid fuel for electric cars" -- what if we used refined petroleum as a
secondary energy source? we probably wouldn't even need a large electric motor
any more.

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cagenut
Here's a much better article with diagrams and more details:
<http://www.greencarcongress.com/2011/05/ssfc-20110526.html>

This really will be a major step forward if it pans out. Even if it doesn't
work so great for cars it could be amazing for grid storage.

