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5478Re: Batteries

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  • Scott Provost
    Oct 14, 2005
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      Who at Thunder Sky did you talk to to get pricing? Do they have a US
      dealer or english web site? Valence is around $1.50 a wh.

      --- In evworld@yahoogroups.com, Yodda Pierce <ntsl532@y...> wrote:
      >
      > I just wanted to answer your last question here.
      > Perhaps your question was rhetorical, but you asked
      > what applications would require 3000 Wh/Kg. My
      > thought would be like military vehicles like tanks,
      > amphibious assault vehicles, aircraft, commercial and
      > military, perhaps trucks. Those are a few I can think
      > of. The advantage would be if we had a battery with
      > this type of energy, fuel cells would not be needed
      > due to their high cost. Then all the resources could
      > focus on batteries and the result would be to get a
      > high output EV batery available to the public. The
      > problem right now seems not to be that we do not have
      > a battery that meet the criteria for electric
      > vehicles, but rather that the cost for such a battery
      > pack is very expensive making the electric vehicle
      > 50-100% more than the cost of the ICE vehicle.
      > Therefore, additional resources need to be spent not
      > only to improve battery technology, but rather to
      > improve production methodologies to make these
      > advanced battery chemistries affordable in a EV pack.
      > The lowest cost I could find for a 30 Kwh battery pack
      > was from a company called Thunder Sky in China. It
      > was about $15,000-20,000 which was a decrease of
      > $80,000 from the $100,000 price tag for a similar
      > lithium polymer battery from 3M. Hopefully we can see
      > the prices fall to $1000-$5000 range in the future and
      > we can then see the BEV become very close to the price
      > of the ICE car and have similar range. Of course new
      > battery technologes still need to be considered,
      > however we are now in th e position where existing
      > technology can produce a low weight, high power output
      > EV battery pack. We just need to get the price down.
      >
      >
      >
      > --- Paul Scott <pscottvfx@e...> wrote:
      >
      > > Hi All,
      > >
      > > I'm enjoying the talk about batteries. Yes, it's the
      > > crux of the matter. A
      > > while back, I asked a question to the EV lists about
      > > the theoretical limits
      > > to batteries. I got several great responses, but
      > > William Kortoff's seemed to
      > > be the best. I'm reprinting it below:
      > >
      > > At 07:30 PM 3/29/2004, Paul Scott wrote:
      > >
      > > A question for you engineers on the lists. This is
      > > a quote from "Power To
      > > the People" by Vijay Waitheeswaran in a section on
      > > the battery electric
      > > vehicle:
      > >
      > > "The trouble is that battery systems are pushing
      > > the upper limits of
      > > specific energy - the number of watt-hours they can
      > > store for a given
      > > weight. The best that conventional batteries can
      > > achieve theoretically is
      > > 300 watt-hours per kilogram (Wh/kg), though most
      > > manage barely half that in
      > > practice. That is nowhere near enough for the armed
      > > forces. The Pentagon has
      > > said that it wants to deploy portable equipment
      > > loaded with energy-guzzling
      > > features that would require up to 3100 Wh/kg by
      > > 2006. The physical
      > > properties of batteries make it impossible for them
      > > to ever achieve such
      > > goals."
      > >
      > > His comments on the needs of the military
      > > notwithstanding, are his facts
      > > and figures correct on the battery's theoretical
      > > limit? I had not heard of
      > > such a limit and he doesn't explain it at all.
      > >
      > > Paul Scott
      > > 310-399-5997
      > > pscottvfx@e...
      > >
      > > This does remind me of gloom and doom
      > > anti-technology predictions from
      > > the past. It is possible to know and calculate the
      > > theoretical maximum
      > > energy from specific battery combinations---that's
      > > basic electrochemistry.
      > >
      > > The theoretical limits of current batteries are
      > > actually much higher than
      > > 300 wh/kg. The basic reactants of lead acid imply a
      > > limit around 120
      > > watt hours per kilogram, and actual batteries
      > > deliver 20 to 40 wh/kg.
      > > At the other extreme, I believe the reactants of
      > > current lithium battery
      > > chemistries imply a theoretical value around
      > > 1500-3000 wh/kg. The
      > > difference between the theoretical and actual values
      > > results from the
      > > weight of case, electrical conductors, separators,
      > > electrolyte, important
      > > non-reactant ingredients, and reactants that don't
      > > get used.
      > >
      > > Fifteen years ago, the best practical and known
      > > rechargeable batteries
      > > delivered maybe 70 wh/kg. Today, commercial
      > > batteries are reaching
      > > 200 wh/kg. It is fair to argue on a technical basis
      > > that a specific
      > > chemistry will have a definite practical performance
      > > limit. But new
      > > combinations will continue to be developed in the
      > > future; I wouldn't
      > > want to predict where things will go in the future.
      > > I certainly wouldn't
      > > want to predict that technology won't improve beyond
      > > a certain point.
      > >
      > > I can't see what practical applications would need
      > > 3000 wh/kg.
      > >
      > >
      > > /wk
      > >
      > >
      > > > All good points Ernie. To look at electric
      > > vehicles today, one would think
      > > > they all have
      > > > to be small and extremely ugly. Also looking at
      > > hybrids and plug-in
      > > > hybrids gives the
      > > > impression that we will always have an internal
      > > combustion engine in our
      > > > vehicle. But
      > > > predicting the future can make everyone look
      > > silly.
      > > >
      > > > For now, the plug-in hybrid looks like the best
      > > "vehicle" to blaze the
      > > > trail to a pure
      > > > electric vehicle. Biofuels definitely fit well
      > > with a plug in hybrid and
      > > > hopefully we
      > > > will see both these technologies blossom soon.
      > > With the history of battery
      > > > electric
      > > > vehicles, it's easy to understand why they seem
      > > limited to small marginal
      > > > units. But
      > > > every single limitation of the battery electric
      > > vehicle that I've been
      > > > able to think of,
      > > > all leads back to the battery. The next question
      > > one must ask oneself is,
      > > > has battery
      > > > technology already reached its zenith. If we
      > > listen to General Motors and
      > > > others, this is
      > > > the case. They claim that they've given up on the
      > > battery and have moved
      > > > on to the
      > > > hydrogen fuel cell. What they actually claim is
      > > that they've given up on
      > > > the electric
      > > > vehicle, but we all know a hydrogen fuel cell
      > > vehicle is nothing but an
      > > > electric vehicle
      > > > that gets its electricity from the fuel cell.
      > > >
      > > > Possibly the battery has run up against a
      > > technological brick wall.
      > > > Possibly General
      > > > Motors is being genuine and does not have a hidden
      > > agenda in their
      > > > campaign to explain to
      > > > us why they have given up on the battery electric
      > > vehicle. But while
      > > > General Motors and
      > > > US Car may have given up, others still have some
      > > hope for the battery. My
      > > > belief is that
      > > > battery technology is still in its infancy.
      > > Materials science along with
      > > > growing need
      > > > from all sectors of society may still produce some
      > > very pleasant and
      > > > exciting battery
      > > > technology surprises for us in the future.
      > > >
      > > > Why should a battery be any different than the gas
      > > tank? Why can't a
      > > > battery be superior
      > > > to a fuel tank? If the battery can be recharged in
      > > about the same amount
      > > > of time it takes
      > > > to fill the fuel tank, that eliminates one of the
      > > biggest gripes. If the
      > > > battery can be
      > > > made to work in all weather conditions, another
      > > common gripe goes by the
      > > > wayside. And if
      > > > range can be achieved similar to that of liquid
      > > fuel vehicles, no one will
      > > > have that to
      > > > complain about. There or still cost and
      > > environmental and other issues to
      > > > consider but I
      > > > see no brick wall.
      > > >
      > > > Why couldn't a large truck be a pure battery
      > > vehicle? What, other than our
      > > > current
      > > > perceptions or misperceptions makes something like
      > > this impossible. It's
      > > > tough to twist
      > > > our minds in new ways and as we predict the future
      > > were sure to look like
      > > > fools at times.
      > > > There is also a lot of inertia to break through,
      > > as with any new concept.
      > > > The electric
      > > > vehicle is generally understood to have certain
      > > characteristics. Even
      > > > people who are
      > > > usually up on the latest technologies and are
      > > knowledgeable about vehicles
      > > > in particular
      > > > will often hold some very incorrect views about
      > > electric vehicles. Battery
      > > > electric
      > > > trucks may still be a long way off but the view of
      > > all electric vehicles
      > > > as being slugs
      > > > on the road is about to be shattered.
      > >
      > === message truncated ===
      >
      >
      >
      >
      >
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