Re: Cross-country dreaming

classic Classic list List threaded Threaded
7 messages Options
Reply | Threaded
Open this post in threaded view
|

Re: Cross-country dreaming

Myles Twete
Roger offered:
> IMHO: If EV's are ever going to be a practical cross-county EV, it will have
> to be with the permanently installed battery pack.

That's true only because we don't have the will to make infrastructure changes.
However, to be able to do 10hr days at 60mph with a 200mi range EV without 2 pack exchanges would require at 1C recharge rates.   And you're talking 9-10kw recharge rates.  Which, unless you have 3-ph power or 220v/50a in place requires infrastructure also.
SO either way, infrastructure is required.

> As mentioned earlier, there isn't any easy way to "plug & play" a 1000lb., or more, battery pack.

Maybe you didn't see how Milburn did it in 1917? http://www.milburn.us/docs/27_instr-08.jpg
Nearly every EV mfr back then split the pack in 2.
Most EV converters today are advised to split the pack in 2.
So you're not talking about a single 1000# lump pack swap.
It would more likely be 2 - 500# lumps.

> Not only that, but can you imagine the facility and equipment that would be
> needed to service, for example, several hundred EV's on a busy day? (You are
> going to locate the faculty next to a busy freeway, aren't you?)

Visualize this:
A limited number of swappable packs would be available at a given station at a given time.
First come, first served.
If they're out of charged packs, there may be one that's almost charged or could be swapped in as a limited capacity one.
Failing that, you'd ask to have your pack recharged at 1-C or 5-C rate, whatever.  Perhaps even dump charge for the daring.
View these as fast recharge facilities which have the added capacity to swap out a limited number of a limited number of standard packs at a given time.

-MT
_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
Reply | Threaded
Open this post in threaded view
|

Re: Cross-country dreaming

Lee Hart
Roger offered:
>> If EV's are ever going to be a practical cross-county EV, it will
>> have to be with the permanently installed battery pack.

[hidden email] wrote:
> That's true only because we don't have the will to make infrastructure
> changes.

>> there isn't any easy way to "plug & play" a 1000 lbs battery pack.

Actually, there is. Fork lifts routinely swap 1000 lbs batteries several
times a day. They may have 3 batteries per lift truck; one in the
vehicle in use, and two more in the rack being charged (in preparation
for the next 8-hour shift). It only takes a minute or two.

This isn't an engineering problem; we can do it if we want to. It's
psychological and economic problem -- can we convince people to do it,
and does it make economic sense to do it.

In the case of fleet vehicles like fork lifts, it makes sense. The plant
just orders their drivers to swap pack each shift. The economics work
because the plant owns all the equipment and infrastructure (no
squabbling about who's responsible, or who's going to pay for it).

I would guess you're likely to see EVs with quick-change packs when they
are used for deliveries, or on a regular route, or as part of a fleet of
vehicles owned and operated by the same company.

You might also see them used by individuals that want one vehicle to
serve several different purposes. For example, our Sunrise EV2 is being
designed with a quick-change pack. You could have a "cheap" pack for
daily around-town driving, a "high-power" pack for racing on weekends,
and even a hybrid "range" pack with batteries plus an ICE generator for
long trips.

You just need to use your imagination. There are as many ways to deal
with the problem as there are people to dream them up.
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in    --    Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
Reply | Threaded
Open this post in threaded view
|

Re: Cross-country dreaming

dbeard@netzero.com
In reply to this post by Myles Twete
Allot of the infrastructure for this is already in place. I can excihange propane tanks, I can rent a U-haul trailer, I can go into walmart, or Lowes and swap 5 gallon water bottles....heck I can buy minutes to charge up my cell phone and get propane both from the 7-11.

Advance auto will check the battery system in my ICE minivan for free and if I buy a battery they will install it.....The geek squad from circuit city could be trained to troubleshoot problems, upload algorythms to the BMS....

And batteries don't have to weigh 1000 lbs, Valence sells Modules for Uninteruptible Power Supplies through tyco electronics....Elite RK series.

IF your conversion is getting 80 mpc on lead acids...you can still use the range for lithium if it is meeting your local driving requirements.....but large format lithiums would be a third of the weight...or better
_____________________________________________________________
Click now and invest wisely with these mutual fund resources!
http://thirdpartyoffers.netzero.net/TGL2221/fc/Ioyw6i4ujzafeIqG60C0wTCPvcvw4jJUSAH9MUmYzmjxZDZODS9IGj/



_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
Reply | Threaded
Open this post in threaded view
|

Battery Swapping (was Re: Cross-country dreaming

Peter VanDerWal
In reply to this post by Lee Hart
I doubt we'll ever see a mass produced consumer EV with large swappable
packs.

In my opinion it makes more sense to use smaller 'modules', say around 30
lbs.  The modules would have a built in BMS, handles charge/discharge as
well as tracking module health, etc.
These could be swapped by hand if needed, or the vehicles could have some
system (perhaps like a belt) to spit out the modules.

This allows an easy upgrade path for new tech in batteries AND allows
customizing the total pack for the vehicle.
Maybe 2 or 3 packs for a motorcycle, 10 or 20 for a car, 50 for a truck, etc.

Having small modules allows smaller indepent service stations (doing hand
swapping) and larger automated systems at bigger, busier locations.

This also requires smaller, incremental, changes to the existing
infrastructure.  Service stations only require electrical service sized
tothe energy requirements for the average number of packs they handle per
day.

The major problem would be that the automakers would have to agree on a
standardized module, at least as far as physical size, connections,
voltage, etc.

> [hidden email] wrote:
>> That's true only because we don't have the will to make infrastructure
>> changes.
>
>>> there isn't any easy way to "plug & play" a 1000 lbs battery pack.
>
> Actually, there is. Fork lifts routinely swap 1000 lbs batteries several
> times a day. They may have 3 batteries per lift truck; one in the
> vehicle in use, and two more in the rack being charged (in preparation
> for the next 8-hour shift). It only takes a minute or two.

--
If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever I
wish with the message.  By posting the message you agree that your long
legalistic signature is void.

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
Reply | Threaded
Open this post in threaded view
|

Re: Battery Swapping (was Re: Cross-country dreaming

mos6507-2
Something like a really large version of the DeWalt packs?

-----Original Message-----
In my opinion it makes more sense to use smaller 'modules', say around 30
lbs.  The modules would have a built in BMS, handles charge/discharge as
well as tracking module health, etc. These could be swapped by hand if
needed, or the vehicles could have some system (perhaps like a belt) to spit
out the modules.


_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
Reply | Threaded
Open this post in threaded view
|

Re: Cross-country dreaming

Evan Tuer
In reply to this post by Lee Hart
On Jan 3, 2008 12:53 AM, Lee Hart <[hidden email]> wrote:

> Roger offered:
> >> If EV's are ever going to be a practical cross-county EV, it will
> >> have to be with the permanently installed battery pack.
>
> [hidden email] wrote:
> > That's true only because we don't have the will to make infrastructure
> > changes.
>
> >> there isn't any easy way to "plug & play" a 1000 lbs battery pack.
>
> Actually, there is. Fork lifts routinely swap 1000 lbs batteries several
> times a day. They may have 3 batteries per lift truck; one in the
> vehicle in use, and two more in the rack being charged (in preparation
> for the next 8-hour shift). It only takes a minute or two.
>
> This isn't an engineering problem; we can do it if we want to. It's
> psychological and economic problem -- can we convince people to do it,
> and does it make economic sense to do it.

Indeed it's already done for road-going EVs some places:

http://www.cru.uea.ac.uk/tiempo/newswatch/feature060527.htm
[..]
Most Safa Tempos are used to ferry commuters within the Kathmandu
Valley. Each Safa Tempo travels a distance of 100 to 120kms each day
on two sets of batteries. A battery set contains twelve six-volt deep
cycle lead acid batteries with a full charge capacity of 185 ampere
hours. These batteries on full charge show 77 to 79 volts, then
discharged to 72 volts during operation. After the first set of
batteries has completed 50 to 60kms, the Safa Tempos return to the
charging stations where the other battery set is loaded onto the
vehicles for an additional 50 to 60kms of operation.

Through this system, Safa Tempos have been providing a cheap and
dependable form of transportation to the people of Kathmandu. On
average, 100,000 passengers travel by Safa Tempos every day. For its
size of city, Kathmandu most probably uses the largest fleet of
electric vehicles for public transportation in terms of the ratio of
electric to fossil-fueled public transport vehicles. Four new Safa
Tempos with enhanced features are currently being manufactured to meet
the tourism industry's need for clean transportation.
[..]

Personally I still prefer the idea of fairly high-power charging
(40miles per hour or so  / 10kW).  It's just easier to start with.

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
Reply | Threaded
Open this post in threaded view
|

Cross-country proposal Australia

David Sharpe
I would be interested in hearing about the experience of USA participants in
the last across US event. Im going to put up the idea of a Melbourne to
Sydney (Australia) & return EV trip using charging at substations & camping
grounds with some traveling power sources for the chain draggers. I think we
need at least 80ks range.
David Sharpe


_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev