

Low batteries on your Tesla? Swap ‘em out - waster
http://blog.sfgate.com/energy/2013/06/18/low-batteries-on-your-tesla-swap-em-out/

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codex
I wonder if this is motivated by ZEV credits; I think rapid refill zero
emission vehicles qualify for a lot more credits--possibly even if no owners
take advantage of the feature. So just having a few rapid recharge stations
that nobody uses could be a huge financial windfall for Tesla, allowing them
more profit on each car sold--again, even if owners never once swap a battery.

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FriedPickles
Source? My search was fruitless.

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codex
www.greencarcongress.com/2013/05/zev-20130502.html

Looks liken California is thinking of closing this loophole; nothing a little
lobbying can't fix.

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mbenjaminsmith
If we're going to be swapping things at charging stations, why not use a
technology like this:

[http://www.phinergy.com/](http://www.phinergy.com/)

Takes a refill of plain water every ~200 miles and a swapping of aluminum at
larger intervals. Aluminum is common as is the recycling of it. It's also a
lot easier to handle than battery packs I would imagine -- lighter, safer,
etc.

Not sure about the range but early press suggests it to be at least 1k miles
between changes. I put around 4k miles on my car a year (much lower than
average, I know). I take my car in at least twice a year for service so it
would get half of them "for free".

Even at 12k miles per year that's only once a month. If it could be done in 15
minutes (a number I just made up) that's not much of a PITA.

I wonder what the cost would be vs gasoline vs the cost of buying a car packed
with LIBs.

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coryrc
> why not use a technology like this

Because it is highly inefficient, requires a large infrastructure, is
susceptible to air pollution, and has low power density?

Versus battery electrics have infrastructure at every home, are upwards of 93%
efficient, don't use air, and have plenty of power.

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mbenjaminsmith
> and has low power density

Wikipedia:

"They have one of the highest energy densities of all batteries ... an
electric vehicle with aluminium batteries has the potential for up to eight
times the range of a lithium-ion battery with a significantly lower total
weight."

> Because it is highly inefficient

I just read in the 20 - 30% range. One, that's a lot better than a gas burner.
Two, your magical 93% doesn't account for the efficiency of the source of the
electricity. Over 40% of the electricity produced in the US is from coal. The
average efficiency of a coal plant is around 30%.

Coal plants are also the #1 source of greenhouse gasses in the US.

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skaevola
I don't think battery swapping is a great idea. The problem is that the
battery is such a huge part of the car's cost. I can only guess, but I would
estimate $15,000-20,000. Getting someone else's poorly treated battery could
drastically effect the resale value of the car. The other company in the
article tried to mitigate this problem by actually owning the batteries, but
that isn't Tesla's model.

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waster
If I understand the idea correctly, you'd be swapping out your (depleted from
a road trip) battery for someone else's (or Tesla's, if they shifted to a
model where they provide some of the batteries at the swap-out stations), and
then next time you wanted to swap again, you'd get another one. Doesn't seem
to me to be a factor for resale. Seems like they're pitching it instead as a
way to increase the range of a car while on the road, though I'm willing to
say I've misunderstood based on my (twice) read of the article.

If they are planning to release further detail Thursday, though, that'll
presumably clarify.

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sp332
If they take my (say) brand-new Southern California battery and replace it
with someone's two-year-old Salt Belt battery, that's going to decrease the
value of my car.

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schiffern
> _that 's going to decrease the value of my car._

Forgive my ignorance, but how? Cheap battery swapping would mean that all
batteries are essentially fungible. What stops the new owner from just
swapping batteries again? What stops _you?_

You're also forgetting that Tesla has a _very_ generous battery warranty.
Unless you don't think they'll honor it.
[http://money.cnn.com/2013/04/26/autos/tesla-service-
gaurante...](http://money.cnn.com/2013/04/26/autos/tesla-service-
gaurantee/index.html)

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sliverstorm
_Cheap battery swapping would mean that all batteries are essentially
fungible_

Which will be interesting. I wonder if at that point the "tragedy of the
commons" would start to set in. "Oh, it's ok if I run this battery totally
flat all the time, it will shorten the battery's lifespan a lot, but I can
just swap it for another!"

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schiffern
Why would you leave your car intentionally empty? Why inconvenience yourself
like that?

There might be people who _can 't_ plug in, but that'll happen regardless of
swapping. You might make the argument that swapping could convince more people
in that situation to buy the car, but that's hardly a downside for Tesla
Motors.

>it will shorten the battery's lifespan a lot

It doesn't do that if you set your depth-of-discharge correctly. Lithium cells
are more sensitive to temperature than charge cycles anyway.

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waster
Though I'll believe it when I see it in (user) action, this would make a huge
difference, IMHO, in the usability of the car. It would make it truly feasible
to drive to Tahoe from the Bay Area, for example. _That 's_ something I'd pay
for.

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schiffern
::checks GMaps:: TIL a 4 hour 20 minute trip is unfeasible, but a 3 hour 50
minute one is fine. ;)

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waster
Until you're traveling at freeway speeds, in cold weather.

[http://www.nytimes.com/2013/02/10/automobiles/stalled-on-
the...](http://www.nytimes.com/2013/02/10/automobiles/stalled-on-the-ev-
highway.html?pagewanted=all&_r=0)

So I'm not sure even 3 hr 50 m would do it?

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DannoHung
High overhead, but if it can be done quickly and for a not exorbitant price,
probably a winning idea. I imagine they'd charge people a yearly service to be
in such a program.

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lingben
wasn't this the premise of the Israeli startup, Better Place? which just went
bankrupt?

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softbuilder
The article talks about that.

