EV Digest 6004
Topics covered in this issue include:
1) Re: Getting an AC motor inverter built
by Jack Murray <[EMAIL PROTECTED]>
2) Re: OT fiberglass questions
by GWMobile <[EMAIL PROTECTED]>
3) Re: Getting an AC motor inverter built
by Jack Murray <[EMAIL PROTECTED]>
4) Re: Siamese low power setup
by Jim Husted <[EMAIL PROTECTED]>
5) Re: What is the future of Li BMS?
by =?ISO-8859-1?Q?Jukka_J=E4rvinen?= <[EMAIL PROTECTED]>
6) What's up with posting?
by <[EMAIL PROTECTED]>
7) Re: cost effetive, long range EV's,
by "jerryd" <[EMAIL PROTECTED]>
8) Re: Intelect 9 ah D cells.
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
9) Re: $25,000 Performance Car?
by David Dymaxion <[EMAIL PROTECTED]>
10) Assembled nickal metal hydride Bat. Packs
by Steven Lough <[EMAIL PROTECTED]>
11) Re: Getting an AC motor inverter built
by Ray Wong <[EMAIL PROTECTED]>
12) Re: cost effetive, long range EV's, bitching ,Re: $25,000 Performance
Car
by Eric Poulsen <[EMAIL PROTECTED]>
13) Re: air suspension - Roland, got your ears on?
by Eric Poulsen <[EMAIL PROTECTED]>
14) Re: Pricing Lithium-ion Valence Group buy
by "Peter VanDerWal" <[EMAIL PROTECTED]>
15) Re: lee's emeter companion?
by Victor Tikhonov <[EMAIL PROTECTED]>
--- Begin Message ---
Don, I've asked about this motor on the list, it has a funny output
shaft that apparantly is not going to be easy to mate with. If the motor
was cheap enough, would be worth figuring it out, but not at marvin prices.
Of course, the AC24 and AC55 AC motors are available as new and
supported motors from Azure at similiar prices.
Jack
[EMAIL PROTECTED] wrote:
One mans cheap is another mans expensive but I think these are fairly
reasonable and they have hundreds of them. If anyone is interested in multiple
units they will deal on price. They have their phone number listed.
_http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=230029345207_
(http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=230029345207)
If anyone wants a good deal on a single one contact me.
Don
In a message dated 10/11/2006 12:16:28 PM Pacific Daylight Time,
[EMAIL PROTECTED] writes:
The big problem is the motor, three phase EV motors aren't that cheap or
easy to
come by.
Anyway, just thought I'd mention it, back to sundays of building my A123 BMS.
Regards, Rod Dilkes
--- End Message ---
--- Begin Message ---
The largest surfboard foam maker clark foam closed causing panic in the
surfboard industry.
Its a whole new ball game now.
Movie sets get blocks of foam 20 feet long and 6 ft wide. Call movie
prop departments at disney, warner or universal and ask someone there
who is a good supplier.
You could carve and form your car body in one piece.
On Wed, 11 Oct 2006 12:05 pm, Cor van de Water wrote:
My father used to make surf boards with fiberglass skin
after shaping the foam.
You can either buy foam blocks or mix and pour it
yourself in the approximate shape you want, then cut it.
My guess is that boat supply shops can give the answer
which foam and where to get and related questions.
They will likely also know about structural connections
between fiberglass elements, as a boat has the same issues.
Success,
Cor van de Water
Systems Architect
Email: [EMAIL PROTECTED] Private: http://www.cvandewater.com
Skype: cor_van_de_water IM: [EMAIL PROTECTED]
Tel: +1 408 542 5225 VoIP: +31 20 3987567 FWD# 25925
Fax: +1 408 731 3675 eFAX: +31-87-784-1130
Proxim Wireless Networks eFAX: +1-610-423-5743
Take your network further http://www.proxim.com
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of Dave Cover
Sent: Wednesday, October 11, 2006 11:25 AM
To: [email protected]
Subject: OT fiberglass questions
Reading a recent post about use of fiberglass for weight savings, it
reminded me of a challenge
I'm facing and I could use some advice. I bought some 1" fiberglass
I-beams
I'm using as strutural
elements in my car. For instance, I'm using two to go between the cars
frame
rails to support my
controller/ contactor package. They bridge the distance nicely and
support
the weight well.
I'd also like to use these as the frame for two door panels I'm making
for
my battery pack. THese
doors will lie flat over the battery boxes and act as the floor to the
hatch
area in the back of
my car. I'll miter the pieces at the corners. Can I just use some of
the
epoxy resin to glue the
I-beams togther in the corners, or is there a better way to connect
these
fiberglass members?
To skin the doors I need to have a flat surface to lay the fiberglass
on and
then the frame. Jerry
mentioned using formica as a mold surface, but I also need a release
agent.
I noticed some of the
release agents are carnuba wax, just like car wax. Even made by
companies
like Maguires. Can I
just use car wax on the formica as a release agent? The door panels
will be
an inch thick with
fiberglass skins, is there a particular kind of styrofoam or other
product I
can use as a light
weight filler in the doors? I'm using regular fiberglass cloth and
epoxy
resin.
Thanks
Dave Cover
www.GlobalBoiling.com for daily updated facts about hurricanes,
globalwarming and the melting poles.
www.ElectricQuakes.com daily solar and earthquake data.
--- End Message ---
--- Begin Message ---
http://www.pwrx.com/pwrx/docs/cm200rl_24nf.pdf
looks particularly good, price is only $300 ?? if you can get them.
Wouldn't be good to destroy many of them up during testing,
even the $5 mosfets add up quickly.
Jack
Ray Wong wrote:
These PIC18Fxx31 evaluation boards are available on ebay for about $150. Surplus IGBT 600amp/1200v go for about $20. Dual trench gate 300amp/1200V for about the same.
There is whole lot of info from Powerex at
http://www.pwrx.com/igbt.asp?catid=50
Check the application notes. They even have PCB layouts for isolated universal
gate drivers. Others on the list have listed many other great sources of info.
You can probably take the PIC evaluation board, some IGBT and customize the
software to make AC controllers, BLDC controllers, sepex, DC controllers.
It has been 20 years since I brought out the breadboard but I use to be a good
design EE. Anyways, I have already ordered one of these PIC18Fxx31 evaluation
kits, along with some PIC16F877A evaluation kits, a dozen big IGBTs and a dozen
dual IGBT, some big fast diodes, big caps, etc.
The PIC16F877A may work well for a DC controller. JB Staubel (AKA Tesla design
guy) built one for his 944 Porshe so we know it works.
http://www.jstraubel.com/944EV/EVproject.htm
I have a few ideas for getting regen onto a DC motor. It would be nice to have a 1000 amp higher voltage DC controller with regen.
EZESPORT
----- Original Message ----
From: "[EMAIL PROTECTED]" <[EMAIL PROTECTED]>
To: [email protected]
Sent: Wednesday, October 11, 2006 8:52:32 AM
Subject: Re: Getting an AC motor inverter built
I haven't been following the thread about AC motor control but I have mentioned
this before and will mention it again. The control bit is not a problem, just
check out this site:
http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1406&dDocName=en010071&part=DM183011
I have one of these boards and it seems to me that the control is all there
ready to go. You just need to upgrade the IGBTs (and maybe drivers) to EV (say
20KW) power ratings. It can be done.
The big problem is the motor, three phase EV motors aren't that cheap or easy to
come by.
Anyway, just thought I'd mention it, back to sundays of building my A123 BMS.
Regards, Rod Dilkes
--- End Message ---
--- Begin Message ---
Hey GW, all
Well, I thought I'd chime in here.
I'm not going to use the words cost effective concerning a true Siamese motor
(not just a coupled motor setup), being it takes a lot of work to put one
together, but I'm hoping that I can achieve a cost that people would consider
reasonable 8^ )
Here's my take on the matter. First by using smaller motors they are able to
rev-up faster with the smaller rotating mass (not to mention a higher rpm
rating). Second you increase the brush and comm area by using two smaller
comms and brush rings as opposed to a single larger comm and brush rigging.
This allows each comm and brush set to share the load and the heat which is a
total plus. The ability to have a series / parallel shift is something that I
think would excite those who have those nasty hills I hear about for the daily
drivers out there. Being each motor shares the load each half runs much
cooler, so I wouldn't try running just one (unless your limping home because
one side had an issue 8^ )
I found this post funny being I am currently building a Siamese6 which I'll
be putting up for sale once I've completed it. I wasn't going to let the cat
out of the bag just yet but I thought it was time for a smaller version of
Johns motor and well now is as good a time to announce it as any I guess 8^ P
This will be created using (2) 6.7" ADC motors that will be appx. 19" long from
nose to nose when completed. It'll have the standard 1 1/8th" keyed shaft that
you'd find on the ADC or Warp motors.
It should come in at right around 80lbs. It will end up being very close to
the L91 (a little longer) in size but have a larger brush and comm mass when
the two are totaled together with a series / parallel shift ability.
This should make an awesome smaller car or motorcycle motor (if one can fit
19"). I don't have a cost as of yet being I'm still building it, but I'll try
and get some pics of it compared to an L91. I guess I thought I'd post this
info now being if anyone's interested I could paint it to their choosing rather
than what I might otherwise do.
Anyway if anyones interested in a "little John" motor contact me off list. I
doubt this will sit at the shop very long 8^ )
Cya
Jim Husted
Hi-Torque Electric
GWMobile <[EMAIL PROTECTED]> wrote:
Oops to john wayland not jack,
John is it more cost effective to siamese two 5hp electrics than buy one
motor with the same power.
Can you turn off one of them when cruising for more range.?
www.GlobalBoiling.com for daily updated facts about hurricanes,
globalwarming and the melting poles.
www.ElectricQuakes.com daily solar and earthquake data.
---------------------------------
Yahoo! Messenger with Voice. Make PC-to-Phone Calls to the US (and 30+
countries) for 2¢/min or less.
--- End Message ---
--- Begin Message ---
Getting a hot lithium cell is already a really bad and wrong way.
Thermal balance is good to maintain but if it is not possible you need
to calculate the effect off and compansate it by treating the battery a
bit differently. It's far from simple. Equation has a quite many variables.
I'm hinting here something almost like this but not exactly.
As you might know there is no absolute SOC points with Lions. The
operational capacity window can be calibrated to certain level and it
already helps a lot.
yes. It is not using the "100%" of the cell but the 100% is anyway
different for every cell.
Question would be that how do you discharge 100 Ah from 90 Ah cell but
take only 70% DOD ?
-Jukka
Jack Murray kirjoitti:
ok, so I think I understand what you are hinting at here,
you stop charging when the weakest (hottest) battery is full, rather
than keep (over)charging until all of them are full.
Doing that with Lions you will certainly have fire or failing cell with
very short lifetime.
That might work okay, but of course, you double the life of a bad cell
at the expense of less total capacity. One must do the math and get
some test results to see the optimum point of reduced lifetime vs
reduced capacity. And of course, one could tweak the amount of
overcharge to add a third variable to the equation.
Certainly for NiMH, just measuring the cell temperature and report it to
a central charger controller would be sufficient. I recommend using
temp to stop charging for R/C packs, and use voltage drop as failsafe.
That could be done pretty cheap, a temp sensor per cell and a simple MPU
with ADC to report the numbers. A cheap MPU has 8 ADC channels, so an
8-cell block would work best, or seperate ADC chips have 16 inputs.
If you have multiple strings, as you would need for 9aH cells, you could
physically migrate the weak cells into the same string, and somewhat
equalize them that way, each string would be more balanced. eventually
the weak string would degrade enough that you replace the cells, but you
would keep good strings with fuller capacity.
Jack
Jukka Järvinen wrote:
You are partilly right here.
But the main point is that doubling the weakest cell lifetime with
less cost than buying a new set of "weak cells" you are getting
noticeable benefits. (since you after all will have more and more
failing cells after cell replacements by straining the next "weakest
link" more).
For hobbyist it's perhaps ok to tinker with the pack but for average
Jane it's just too much to pop up the hood once a month to replace bad
cell.
Since most of the other parts of the EV will have long lifetime and
service free life why should battery be any different ?
Small EV manufacturers will not be able to enable extencive service
network as great unwilling car OEMs can. So we should have as service
free system as possible.
In theory Lithium cells will work very long time without any service.
In real life we need to babysit these puppies well so they push their
best for us for much longer.
And as I said earlier.. It will not be that expencive to make "BMS" or
BMS in quantities. It can be less than $10 per 200 Ah cell. So is $210
for 200 ah 3,6 V cell too much ?
-Jukka
Jack Murray kirjoitti:
Jukka, interesting comments. But why not just let the bad cell fail,
and then replace it? It does need to be identified, that is
critical, but might be a lot more effective to do that than go to a
lot of trouble and expense to keep all the batteries equal. just a
thought.
Jack
Jukka Järvinen wrote:
The most wrong way to manage Lion cells is to cure symptoms. The
cells behaviour can be predicted easily as long you know the
surroindings and enviromental conditions.
Rarely cells fail just by using them. You can easliy see the
potentially failing cell by measuring it before putting it evne in
the pack. I could say that 98% of all failed cells I have had have
resigned from their post due misuse. At the moment my experience is
limited to a bit over 1 000 000 Ahs in total of used and tested
lithium cells. (Co,Mn,Fe)
Most wrong way is to find the balance with voltage only. At least
with the cells I have used. Pack is badly out of balance if you
charge all cells to 100% SOC and start using them from there.
Weakest link will fail first and much sooner thant you expect. If
you start bypassing the current over the cells you will need heavy
and perhaps even expencive way to do it.
Voltage is a good reference but not only source of SOH information.
Track current, temperature and history data and it will work.
And now someone thinks it will be expencive. It can if not done
correctly.
Lets say you get the double mileage with same pack of cells with BMS.
Why ?
Without it the weakest link will use most highest individual DOD in
the pack. So it has lowest cycllic life too. Best cells have less
and less DOD in every cycle since their rate of death is much lower.
There will be 200 to 300 % difference in the lifetimes. With certain
conditions even more.
By adjusting the operational capacity window parameters you can
choose the rate of death. Higher cell voltages in end of charge
fastens the electrolyte dissolving. Also using heat to lower the
impedance during charging you can adjust the lifetime of the cells.
This is where I have the border between "BMS" (voltage limitations
with tempsensors) and BMS (historical database to define lifetime
trends and capacity based balancing to match the cyclic and
electrolyte lifetime)
Now the 10-20% added price on the plain Lithium cells has nicely
been justified by the doubled lifetime. That's the cost of BMS today.
If we would live in perfect world and all cells would be identical
and electrolyte would not be damaged by overcharging, all extra
energy put to cell would just transform to cold air or light or
cosmic radiation.. We would be able to make briefcases with 300 kWh
energy...
There are pending patents on the issues mentioned up here earlier
and when they are all public anyone with non-commercial activities
can find their ways to implement it.
I can see 30 kWh Lion packs with all necesary auxiliary devices
(3200W Chargers, computers, touch screens, controller boards for
pedals and contactors, cell electronics) with less than 15000 USD in
near future. VERY doable. When all gets to it's place you can even
half that price.
So what I do think about BMS over all (OEM world)... In future there
will not be a BMS sold separately.
It integrates to cell structures. OEM type manufacturing of the
technology is already existing. The "BMS" makers will still be there
and doing their thing. From there they do the very important work to
test the theories and existing technology. They do not eat anything
without chewing it throughly.
There are still at least 500 Lithium battery manufacturers world
wide. They sell to anyone they can. Small players will vanish or
stay in small markets. Big players buy all potential technology they
see and it evolves from there as any other industry.
Just my personal opinion...
-Jukka
Mark Fowler kirjoitti:
Hi all,
John's and Victor's Li-BMS systems monitor the voltage and bleed off
excess charge current.
They attach (in parallel) to an already connected battery string.
The circuit boards in these links actually connect the batteries
into a
series string.
All current runs through the circuit itself, allowing the circuit to
monitor the current as well as voltage, and to disconnect the
batteries
in fault situations.
This is fine for relatively low currents (like in R/C models or
bikes or
scooters) but doesn't scale up too easily without redesigning how the
whole thing works (i.e. where the current flows).
These systems are cheap because of mass production.
(I wonder how big the R/C market is in terms of total KWh of batteries
compared to the EV market...)
There are chips like
http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2931
that do the bulk of the work for you - just wrap a circuit around them
to plug everything in to.
Once again - the problem is that these chips expect the current to be
flowing through them to do their job, so they only handle low
currents.
I'm sure there's a way of building a circuit based on such a chip that
used a current divider so that the chip only saw a tiny fraction of
the
real current, enabling it to handle EV currents and still give useful
voltage info and some overcharge regulation (through another heat-sunk
part of the circuit).
(I'm an electronics noob, so don't ask me how to do it :-)
Mark
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Don Cameron
Sent: Tuesday, 10 October 2006 1:43 PM
To: [email protected]
Subject: RE: What is the future of Li BMS?
We already have people on this list developing lithium BMS for higher
amperage EV needs today. Victor should have something out soon.
Also, I
think John L has or is developing something.
I sure like these little modules, at $45 for the 10 cell unit,
needing 9
units for 312V, approx $500 for BMS is pretty good. Too bad the
max current
draw is only 27A.
I wonder, it the circuit can be modified easily to handle 300A or
even
1000A max draw?
Don Cameron, Victoria, BC, Canada
see the New Beetle EV project www.cameronsoftware.com/ev
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On
Behalf Of Ryan Stotts
Sent: October 9, 2006 7:49 PM
To: EVDL
Subject: What is the future of Li BMS?
Look at these products and based on what you see, what do you
foresee on the
future price for items such as this and also, the reality and
likelihood of
us owning products like this?
Is THIS the beginnings of an off the shelf universal BMS system?
http://www.all-battery.com/index.asp?PageAction=VIEWPROD&ProdID=911
http://www.all-battery.com/index.asp?PageAction=VIEWPROD&ProdID=908
http://www.all-battery.com/index.asp?PageAction=VIEWPROD&ProdID=912
http://www.all-battery.com/index.asp?PageAction=VIEWPROD&ProdID=910
http://www.all-battery.com/index.asp?PageAction=VIEWPROD&ProdID=909
Where do we go from here? What is to be done next? Do items like
this do
anything for us; or are we no further along now then we were?
If this item is nothing; then what will be something and when will
that be
and what will it be?
I see a little PCB and silicon in those pics. How is the imagined
BMS in
your head different then these? How is it better? What does it do
different? How much does it cost and is it cheaper? How will a
BMS ever be
cheaper? What components are currently not available now that
need to be?
How will any prices go down? You know what component prices are.
Have
prices for any components ever gone down? When and how much?
Is BMS a reality or a farce? Will or will not happen in our
lifetimes?
--- End Message ---
--- Begin Message ---
I've tried to post my smart glider vehicle for sale twice today and it
doesn't show up.
What am I doing wrong Admin??
Pedroman
--- End Message ---
--- Begin Message ---
Hi Ryan and All,
Little late in your e mails?
----- Original Message Follows -----
From: Ryan Bohm <[EMAIL PROTECTED]>
To: [email protected]
Subject: Re: cost effetive, long range EV's,
Date: Wed, 11 Oct 2006 13:40:42 -0600
>Hi Jerry and all,
>> Take my soon to be done EV that weights 600 lbs
>> without batteries, over twice that with, yet the battery
>> pack only costs $800 and will get me between 100 and 150
>> mile range on a charge and 80mph+ top speed.
>Do you have a website showing what you're working on or
>what you've done? My 30 second Google search didn't turn
>up much. I'm really interested to see pictures and specs.
Up until now, most of the work has been getting the
body/chassis done so new pics were not useful.
Here are some older pics and info.
http://www.evproduction.org/wiki/index.php?title=Progress_Pics
The info is about 18 months old from back when we started
the project. Both the info, pics will be put up as they
become clear and it's worth taking a pic of. I've shot some
though they look just like the white mock up/plug, just now
it's black and the actual body.
The doors, windshield are cut out which doesn't look
that good until I get the door windows cut out and the
winshield, installed.
As it looks now, more finished pics, updated info will
be on the wiki on about 10-22.
Google doesn't do Yahoo Groups well. Yahoo it, Jerry
Dycus Freedom EV and much comes up.
Thanks,
Jerry Dycus
>
>Best of luck to you.
>
>-Ryan
>--
>
>- EV Source <http://www.evsource.com> -
>Professional grade electric vehicle parts and resources
>E-mail: mailto:[EMAIL PROTECTED]
>Toll-free: 1-877-215-6781
>
--- End Message ---
--- Begin Message ---
Exactly. For instance the Tzero & Tesla Roadster have each over 6000
batteries. Lawrence Rhodes.....
----- Original Message -----
From: "GWMobile" <[EMAIL PROTECTED]>
To: <[email protected]>
Cc: <[EMAIL PROTECTED]>
Sent: Wednesday, October 11, 2006 12:22 PM
Subject: Re: Intelect 9 ah D cells.
> Anybody run the numbers on assembling an ev from small nickal metal
> hydrides?
> As in consumer electronic equipment types? Or is that what you are
> doing?
>
> On Wed, 11 Oct 2006 8:41 am, Lawrence Rhodes wrote:
> > I goofed on the weight & ah of their pack.
> >
> > But, by referring to capacity of Optima battery, you could get (in
> > theory)
> > a 50-cell pack (10s x 5p config) with 12V 45Ah at estimated weight
> > ~10Kg (22
> > pounds). Given a careful housing design, this pack could be discharged
> > at
> > 50A continuously, and be recharged at 3.6A per 10-cell sub-group.
> > ----- Original Message -----
> > From: "Lawrence Rhodes" <[EMAIL PROTECTED]>
> > To: "Electric Vehicle Discussion List" <[email protected]>;
> > <[EMAIL PROTECTED]>
> > Sent: Wednesday, October 11, 2006 8:11 AM
> > Subject: Intelect 9 ah D cells.
> >
> >
> >> 3.85809 is the weight of one string( each cell is 175 gram) at 12v
> > equaling
> >> 9ah. Just multiply by the ah you need. It would be in units of
> >> 9ah. So
> > an
> >> Optima sized pack would be around 23 pounds & 54 ah. 60 batteries. 20
> >> batteries or about 8 pounds for a BB 17 ah sized battery that is
> >> 18ah for
> >> the d cells. At 5 dollars per cell that is 300 per battery. At 10
> > dollars
> >> per cell that is 600 dollars or what you'd spend for a used Panasonic
> >> NiMh
> >> from a Rav4. Lawrence Rhodes.....
> >>
>
> www.GlobalBoiling.com for daily updated facts about hurricanes,
> globalwarming and the melting poles.
>
> www.ElectricQuakes.com daily solar and earthquake data.
>
--- End Message ---
--- Begin Message ---
John, are your engine weights undressed? My poking around showed about 500 lbs
dressed for the modern LS Corvette motors
(http://www.corvetteactioncenter.com/specs/z06/ls1ls6.html), and about 550 lbs
for the earlier LT series motors. Add the always present air conditioner, and
you'd be looking at about 550 lbs to 600 lbs. My apologies for saying the 700
lbs number (I rounded to the nearest 100 from the Camaro engine weight). The
commonly bantied about number for the LT1 V8 in my Camaro (very similar to the
Corvette LT1 motor) is 650 pounds.
Agreed with the other poster's comment that modern cars are too heavy. This is
one reason why I went with an older 911. About 2500 lbs max, and there was a
racing version that was under 2000 lbs. The 911 motor is a heavy beast at 450
lbs.
Right on about modern Corvettes improving so much -- I'd just move the line to
the C4 Corvette rather than the C5. The awesome handling Corvettes started with
the 4th generation in 1984. With only 205 hp, however, they didn't get the awe
of the newer cars with 400 and 500 hp. Chevy took the common racers trick and
stuffed huge tires under the car. If I were going to race a Corvette, I'd
either get a newer one, or get an '84 and stuff a crate engine into it. Don't
worry everyone, I'm doing my electric conversion first, hopefully it'll be even
faster, but I'm not holding my breath!
Its not really an apples-to-apples comparison to compare stock cars to modified
cars, but you are right it is incredible to see a bone stock Corvette beat
highly modified cars, as I have many times. :)
Pulling this back to Corvette as a donor car, I think it is a worthy car to
consider if you are going for a race car. It'll be strong enough for all the
torque, good aero, and you'll remove alot of weight with that heavy V8 gone.
You'd miss out on the problems of tires rubbing, suspension members bending,
driveshafts vibrating, etc, by starting out with a car designed for high
torque. It would be tough to make it a better drag car than a certain Datsun
1200 unless you went with lithium batteries, but it would shine in the corners,
braking, and top speed departments, and look good doing it.
So the previous paragraph was a long way to say a Corvette donor would be one
of the fastest ways to build a fast electric race car. If you have more time
and money, starting at this point would be 1000 lbs better:
http://www.factoryfive.com/table/ffrkits/GTM/specs.html
----- Original Message ----
From: John Wayland <[EMAIL PROTECTED]>
To: [email protected]
Sent: Wednesday, October 11, 2006 9:00:09 AM
Subject: Re: $25,000 Performance Car?
... One of the heaviest of the Corvette V8
engines, a big block, weighed 503 lb with flywheel and clutch, about 200
lbs. less than that 700 lb. figure...that's a bunch of weight to be
incorrect about. Most of the Corvette V8s in the model years referenced
weighed even less, as in another 100 lbs. less! The average weight of
Corvette V8 engines hovers in the 390 to 430 lb. range. ...
> A car that runs circles around other cars on the racetrack in stock
> form....
With exception noted for the dramatically improved Vettes from 2002 to
present, the Corvette usually fairs pretty bad on the race track when
pitted against other cars in its category. Only the most recent Vettes
from '02 to present have shown they 'finally' handle as one would expect
an expensive sports car to do. Heavy cars corner worse than lighter
cars, and Corvettes are too heavy. A properly set up light sedan with
suspension goodies can beat a Corvette in the curves, and it will do it
at a fraction of the price. In fact, it's great sport to go to the
races and be in the crowd with jaded Vette fans to watch their faces as
their beloved Vettes get whipped by hopped up Datsuns and BMW sedans.
Jack, here's some Wayland history for you...
My oldest brother 'was' a Corvette owner and lover...he no longer is.
The coolest one he had, was his cool white 327, 350 hp convertible '66.
I took him to the 2.5 Trans -Am Challenge races here in Portland, where
he saw light and nimble Datsun 240Z's trouncing the Vettes around the
course. At the same time they were running this 'A' class, B production
class was also on the track....the class where the killer BRE Datsun 510
sedans raced. The legendary BRE 510 sedans were lapping the Vettes, even
though they weren't even racing against them! Jack, I doubt you even
know what BRE stood for, so I'll educate you...Brock Racing
Enterprises...the same Pete Brock who was Carol Shelby's right hand man.
BRE squeezed an amazing 298 hp from the Datsun's normally aspirated 1800
OHC 4 cylinder, and in the trimmed down 510 sedans that weighed 1550
lbs. in racing form, the acceleration was unbelievable! Corning power
was astounding as well. Coming out of turn nine at PIR, the Vettes would
plow and under-steer as they struggled to do better than 75 exiting that
mean curve....after blowing past the Vettes in this turn, the 510s hit
90 and exited with both back tires smoking as they simply walked away
from the Vettes down the straights. How do I know this? I was there,
and, the announcer was giving track speeds and was screaming at the top
of his lungs in excitement over how badly the BRE Datsuns were whupping
those Vettes! On other races, Datsun 1200's modified for racing in C
production also flew around the Vettes in the corners and on the
straights, too!
I bet that I have years more experience working on and around cars set
up for track racing, auto cross, rally, and yes, street racing, than you
have, Jack. In another life, I was heavily involved with an autocross
Datsun 510 and helped work on its suspension mods....the car routinely
won its events, and yes, it even beat many Corvettes around the circuit.
The Corvette guys always assumed their horsepower would overcome their
car's handling shortcomings...they were proved wrong, over and over. The
Vette has always been over-weight, and until recent years, has always
suffered from poor weight distribution. Lean, light sedans have
routinely embarrassed the Corvette on race tracks everywhere.
Please Jack, I don't need lessons about handling!
One more thing....when Tim and I took White Zombie to race the cops at
PIR on their 'officer's evasive and pursuit driving training day', the
cops had two high performance machines at the track in addition to the
cop cars. One was a stock, $45,000 405 hp Z06 Corvette, the other was a
stock $28,000 MazdaSpeed sedan with a 286 hp 4 banger and rally type
suspension. It was a fun day, for sure for all of us. At one time, they
had the Vette and the Mazda on the track at the same time...the Mazda
left the Corvette in all the corners, and in the straightaway, too. In
fact, as the day rolled on and the pursuit excersizes got more intense,
they parked the Corvette and relied on the hot Mazda sedan as it was the
hardest vehicle to keep up with....so much for the Vette being 'A car
that runs circles around other cars on the racetrack in stock form'! The
cops all raved about the neutral handling of the Mazda, there wasn't
much mention about the parked Corvette.
...
--- End Message ---
--- Begin Message ---
Not sure... but at the recent SVEAA Ralley, In Palo Alto folks at a
Start-Up
called Air.Lab had big strings of NMH batteries in a Sparrow.
Contact Info:
http://www.airlabcorp.com
e-mail [EMAIL PROTECTED]
Their flyer on the Sparrow read:
Nimh Parallel GAIA I ...Availabale TODAY !!!
Looks like their
battery groupings came with fans and BMS...
--
Steven S. Lough, Pres.
Seattle EV Association
6021 32nd Ave. N.E.
Seattle, WA 98115-7230
Day: 206 850-8535
Eve: 206 524-1351
e-mail: [EMAIL PROTECTED]
web: http://www.seattleeva.org
--- End Message ---
--- Begin Message ---
Ebay seems to have a lot of surplus IGBTs available for cheap, mostly singles
and duals. Powerex 600A/1200V (600 amps continuous, 1200 amp short term)
singles cost me less than $20 each on ebay but they retail for over $300 each.
The dual IGBT look real interesting for AC/BLDC applications as you only need
three of them for a three phase system. Powerex has an application note for a
single and dual isolated gate driver modules complete with PCBs that mount on
the IGBT. The optocoupler can be driven directly by any of the PIC evaluation
boards with the onboard PWM timers.
Most of the work will involve adding the DC/DC ps, current monitoring, short
circuit protection and safety shutdowns.
It should not cost much to do some testing.
EZESPORT
----- Original Message ----
From: Jack Murray <[EMAIL PROTECTED]>
To: [email protected]
Sent: Wednesday, October 11, 2006 2:07:56 PM
Subject: Re: Getting an AC motor inverter built
http://www.pwrx.com/pwrx/docs/cm200rl_24nf.pdf
looks particularly good, price is only $300 ?? if you can get them.
Wouldn't be good to destroy many of them up during testing,
even the $5 mosfets add up quickly.
Jack
Ray Wong wrote:
> These PIC18Fxx31 evaluation boards are available on ebay for about $150.
> Surplus IGBT 600amp/1200v go for about $20. Dual trench gate 300amp/1200V
> for about the same.
>
> There is whole lot of info from Powerex at
> http://www.pwrx.com/igbt.asp?catid=50
> Check the application notes. They even have PCB layouts for isolated
> universal gate drivers. Others on the list have listed many other great
> sources of info.
>
> You can probably take the PIC evaluation board, some IGBT and customize the
> software to make AC controllers, BLDC controllers, sepex, DC controllers.
>
> It has been 20 years since I brought out the breadboard but I use to be a
> good design EE. Anyways, I have already ordered one of these PIC18Fxx31
> evaluation kits, along with some PIC16F877A evaluation kits, a dozen big
> IGBTs and a dozen dual IGBT, some big fast diodes, big caps, etc.
>
> The PIC16F877A may work well for a DC controller. JB Staubel (AKA Tesla
> design guy) built one for his 944 Porshe so we know it works.
> http://www.jstraubel.com/944EV/EVproject.htm
>
> I have a few ideas for getting regen onto a DC motor. It would be nice to
> have a 1000 amp higher voltage DC controller with regen.
>
> EZESPORT
>
>
> ----- Original Message ----
> From: "[EMAIL PROTECTED]" <[EMAIL PROTECTED]>
> To: [email protected]
> Sent: Wednesday, October 11, 2006 8:52:32 AM
> Subject: Re: Getting an AC motor inverter built
>
>
> I haven't been following the thread about AC motor control but I have
> mentioned
> this before and will mention it again. The control bit is not a problem, just
> check out this site:
>
> http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1406&dDocName=en010071&part=DM183011
>
> I have one of these boards and it seems to me that the control is all there
> ready to go. You just need to upgrade the IGBTs (and maybe drivers) to EV (say
> 20KW) power ratings. It can be done.
>
> The big problem is the motor, three phase EV motors aren't that cheap or easy
> to
> come by.
>
> Anyway, just thought I'd mention it, back to sundays of building my A123 BMS.
>
> Regards, Rod Dilkes
>
>
--- End Message ---
--- Begin Message ---
jerryd wrote:
Take my soon to be done EV that weights 600 lbs
without batteries, over twice that with, yet the battery
pack only costs $800 and will get me between 100 and 150
mile range on a charge and 80mph+ top speed. And can be as
fast as you want it on much less power than those leadmines
most of you drive!!
"Soon to be"?
Any details, or a prototype, or anything tangible? Something that
actually moves and performs as claimed at the price claimed?
--- End Message ---
--- Begin Message ---
Roland Wiench wrote:
Hello David,
I am using a air suspension from Air Ride Technologies.
www.tidetech.com Ph: 812-482-2932
I think you mean http://www.ridetech.com
--- End Message ---
--- Begin Message ---
> Something I just noted on the Valence PDF page that everyone seems to have
> missed. Or maybe I am miss understanding Four series connected batteries
> ( 60 Volt max system voltage)
> So they may not work like I have read this list talking about with 300
> volt or I think I read 480 Volts. This may be a PDF mis-print but you may
> want to verify before that group purchase.
>
I saw that too. I believe it probably has something to do with their
optional, external, battery management system.
Then again, it might be related to their internal battery regulation
scheme, perhaps some kind of problem that crops up when to many regulators
are active at the same time.
It would probably be a good idea for someone who is interested in these to
check into it first though.
--
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.
--- End Message ---
--- Begin Message ---
Cor,
Your reply just tells me that you don't know how to
estimate capacity of your battery in a first place.
If you tell customer he has 20 gal fuel tank and he
gets stuck running out of fuel after spending
15 gallons, he will be unhappy as well.
Note, that fuel consumption rate works accurately,
just initial capacity was assumed wrong.
Same here. BRUSA Wh meter works VERY accurately.
If you assume you have 20 kWh and you indeed
have 15kWh (at the rate you consume normally,
in average), it has nothing to do with
consumption measurement device.
I know, it's 15kW at higher speeds and 20 kWh
at lower, and the difference *can be* compensated
for by Peukert. But normally average people
don't drive slow all day today and fast all day
tomorrow. Experience showed that average usage
is pretty even, so actual capacity *at that average
rate* in kWh can also be estimated good enough.
Yes, if you happen to drive super fast or tow
something, for such trip real battery capacity
assumption *you* make will be wrong, but it is
your ignorance problem, not Wh counter's.
Again, Wh counter just counts Wh.
As I said, high speed driving increases gas
fuel consumption per mile as well, so
you won't quite cover the same amount of
miles driving at 75mph as you wood at 35 mph,
(so, effectively, your fuel tank is smaller
at high speeds) but this doesn't bother you,
does it? ICE fuel gauge has no adjustment for
poorer fuel efficiency. It sure not as pronounced
as shrinkage of the EV battery, but the principle
stands. If *you know* your tank is smaller
if you drive faster, why complain later that
Wh meter didn't warn you?
The job of Wh meter is to measure Wh.
If you want it also to do report degree of
shrinkage of your "fuel tank" you implement
Peukert. But then, when you press accelerator
it reports that you can go 15 miles. Ease
on the pedal, and it reports 25 miles available.
Go up hill, and it reports 5 miles available.
All over place. Having such reports is worse
and more confusing than just knowing Wh spent.
This is why it is not implemented by BRUSA.
But, I have no issues with someone not
liking it. Just get an e-meter then.
Victor
Cor van de Water wrote:
Victor,
You are not addressing the issue.
Without Peukert correction the "fuel gauge"
can read 1/4 full when your batteries are empty,
so you are guaranteeing that a newbie EVer is
going to hurt his pack big time.
This has nothing to do with reading in miles or %
or whatever you want to calibrate your fuel gauge in,
simply the fact that you can take out no more than
15 kWh after you put in 20 kWh (for example) so if
you blindly rely on a fuel gauge counting down the
energy you put in while taking it out to show how
far you would be able to go, you are going to get
stuck at 3/4 the range that you were expecting,
unless you do correct for Peukert and other
inefficiencies.
I know that Peukert is only valid for lead, but
other chemistries are also inefficient, so you
should correct for that as well, only differently.
The fact that this feature is not implemented in
the Brusa tells me that they rather ignored the
problem or received feedback from the wrong people
because when I as a lay person get an indication
gauge and it does not register reliably and may
cause me to run out of fuel while it still
indicates I should have 1/4 capacity left, then I
do not trust that gauge after that any more.
And I already cause a lot of damage (running the
pack too low, possibly reversing cells and in
general I would consider how I could get my damage
back from the people that give me a digitally
accurate indicator and then have it misrepresent
the information so badly.
I would not at all be pleased with a Brusa meter.
Count me out.
Thanks for the warning.
Cor van de Water
Systems Architect
Email: [EMAIL PROTECTED] Private: http://www.cvandewater.com
Skype: cor_van_de_water IM: [EMAIL PROTECTED]
Tel: +1 408 542 5225 VoIP: +31 20 3987567 FWD# 25925
Fax: +1 408 731 3675 eFAX: +31-87-784-1130
Proxim Wireless Networks eFAX: +1-610-423-5743
Take your network further http://www.proxim.com
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of Victor Tikhonov
Sent: Wednesday, October 11, 2006 11:08 AM
To: [email protected]
Subject: Re: lee's emeter companion?
Lee Hart wrote:
Victor Tikhonov wrote:
Lee Hart wrote:
You really should add it, especially for lead-acid packs. The single
most useful number it can provide is State of Charge. Without the
Peukert correction, simple amphour or watthour data is all but useless.
Gee, I didn't realize BRUSA Ah counter designers who purposely chose
not to implement Peukert correction (they easily could have) are such
an idiots who keep producing their useless device...
What is the purpose of the Brusa Ah counter? As an engineering
instrument so a technologically adept driver can measure what he's
doing? Or, is it meant as a "gas gauge" for typical ICE drivers?
The purpose of Ah counter (which is also Wh-counter) is to count
amp-hours (or Wh) spent as you drive. No different from the
gas fuel gauge which shows amount of fuel in gallons (at best)
or 1/2, 1/4 etc. at worst and you have to remember how many
gallons your tank is). ICE fuel gauges aren't calibrated
in miles and people has no issue with that. They learn
quickly to associate 1/2 with, say, 200 miles, or rather
with "I can fill up after tomorrow". Wh consumption is no
different. I know, Wh available depends much more on
how you drive EV than gas consumption in ICE, but the
principle stands: if I got 20 kWh pack and my counter shows
I spent 15 kWh obviously my pack is 1/4 full, e.g. 5 kWh left.
*Then* (and the process is no different than for ICE) I know
that with consumption of 5 miles per kWh, I can go about
5*5=25 more miles before drop dead, plain and simple.
If you adjust for Peukert, you:
a) need to know exactly what it is for your battery
b) need to make adjustment to it based on the temp and age
else it throws one more variable in the mix.
I'm not saying it is useless, but value added is very little
after I already know Wh spent.
Not to mention, that if you use non-lead acid battery,
Peukert adjustment becomes absolute useless feature.
BRUSA's decision not to include this adjustment was
based on the feed back from test drivers whether they
see it as a benefit. Most expressed desire to know
how much energy their vehicle spent and how far they
still can go. This has nothing to do with type of the
battery and adjustments for its characteristics; Ah meter
is just an energy consumption meter.
Only if you try to convert it to miles, adjustment
is needed, but as you said about average Joe, he
does not convert "1/2 of tank" to miles left.
So he wouldn't do it for Ah (Wh) consumed either.
I don't miss lack of Peukert adjustment at all
(well, I don't use lead battery, but when I did,
I didn't miss it either).
I guess it's a matter of personal preference.
Victor
--- End Message ---
