EV Digest 5335
Topics covered in this issue include:
1) Re: AC vs DC; Newbie Question
by "Steve Arlint" <[EMAIL PROTECTED]>
2) Re: Porsche 911 Was: How many amps driving my EV?
by Robert Baertsch <[EMAIL PROTECTED]>
3) Re: Multi charger.
by Mike Phillips <[EMAIL PROTECTED]>
4) Saft nicad price quotes
by "Robyn Lundstrom" <[EMAIL PROTECTED]>
5) Re: Porsche 911 Was: How many amps driving my EV?
by "Stefan T. Peters" <[EMAIL PROTECTED]>
6) Re: 6 volt Hawkers
by Christopher Zach <[EMAIL PROTECTED]>
7) Re: Schaeff Drive Axle Motor from Hyster forklift
by Ray Wong <[EMAIL PROTECTED]>
8) Re: 6 volt Hawkers
by "Mike Phillips" <[EMAIL PROTECTED]>
9) Re: Schaeff Drive Axle Motor from Hyster forklift
by Jim Husted <[EMAIL PROTECTED]>
10) Re: Motor options
by Victor Tikhonov <[EMAIL PROTECTED]>
11) Re: Multi charger.
by Victor Tikhonov <[EMAIL PROTECTED]>
12) Re: AC vs DC; Newbie Question
by Victor Tikhonov <[EMAIL PROTECTED]>
13) Re: Multi charger.
by Victor Tikhonov <[EMAIL PROTECTED]>
14) Re: 80 miles in a Porsche 911?
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
15) General Electric EV-100 SCR Control Forklift EV100 Item number: 7606784790
by [EMAIL PROTECTED]
16) Re: best donor car for 2000lb of lead
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
17) Re: Multi charger.
by Lee Hart <[EMAIL PROTECTED]>
18) RE: Battery Pack Heating
by "David Roden" <[EMAIL PROTECTED]>
19) Re: '74 MG electric on eBay
by "David Roden" <[EMAIL PROTECTED]>
--- Begin Message ---
Greetings,
This is a near impossible question to give a single answer to. When looking at
all of the parameters considered in any EV: motor, controller, batteries,
range, performance, cost, and many others; to simply say AC over DC or vise
versa for all applications cannot be done.
Here is some guidelines to consider though:
1. Long term cost is really defined by the batteries that you use. This is
the consummable in an EV. All other components in an EV "should" last the life
of the vehicle.
2. Both AC and DC systems can offer regen and depending on the controller
design both can do it equally well. AC and Brushless DC have some advantage in
the fact that it has more controllability options. There are really some cool
things that can be done with these motors with respect to controllability.
3. Range is one of the biggest misconceptions that I have seen in AC vs. DC
debates. In reality, it can go either way. All motors are subject to core
loss, ohmic loss, heating effects. A small permanent magnet DC motor can have
better efficiency than a small induction motor. A poorly designed permanent
magnet motor will not. A brushless DC motor has outstanding effieciency. The
more interesting thing to look at is what batteries (generally the biggest
determining factor of range) would be good to use with these systems. Dirt
cheap flooded lead acids tend to work better with lower voltage systems (good
bang for your buck). They do need maintenance however. More advanced battery
types will "shine" more at higher voltages. Keep in mind that there are gray
areas in all of this and nothing is absolute. Don't forget range is also
largely influenced by driving style, aerodynamics, and rolling resistance. If
you want range, choose wisely on a chassis and body.
4. My advice is to come up with a target price first for your conversion.
Then do a bunch of research (google, the EVDL, Wikipedia) and find out what
combination of a motor, controller, batteries, and accesories will best allow
you to complete your EV the way you want to. I see both AC and DC electric
vehicles that perform great.
5. There is no absolute better between AC and DC. Not all AC systems are
expensive, especially when long term operation is considered. Not all DC
systems lack in range. There are AC systems that can "burn" the tires. The
design process you follow in building or buying your EV will be way more
important than participating in the AC vs. DC fight.
VR,
Steven Arlint
Team Umpqua Electric Vehicles
"We put the EV in EVerything,
We put EVeryting in the EV"
--------------------------------
>Assuming two identical vehicles, both driven in an identical manner
>over identical routes and terrain, identical weather conditions,
>etc., IOW: Identical in all respects with the exception of AC (and
>associated AC-paraphernalia), which will have the greater range?
>Now with regen? Which will have the greater range?
>Theoretically, which will have the better (read: "cheaper") operating
>costs, both in the near-term and the long-term (say 10K miles per
>year for 2 years).
>Is this information available elsewhere, and if so, where can it be found?
>Beyond regen, are there any other advantages to AC vs DC?
>I like the idea of regen but if its not cost effective I'm not
>married to the idea.
>Before I can sell "EV" to the boss, I gotta have all my ducks in a row.
>Many thanks,
>Wayne
--
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--- Begin Message ---
David,
excellent chart, I posted your table on the wiki
http://en.wikipedia.org/wiki/Drag_coefficient#Typical_values_and_examples
Do you know how much benefit you get from adding a belly pan? I've
heard it makes quite a difference in improving the Cd.
-Robert
BTW: some people multiply the frontal area* 0.8 to account for the fact
that most cars have sloped sides and are not square when looking head
on. Should you subtract ground clearance?
David Dymaxion wrote:
Don't forget, the important number is Cd*A, Cd = coefficient of drag
and A = frontal area of the car. Using height and width numbers from
<http://www.carpoint.com>, and Peter's Cd numbers, here is a little
table of Cd*A (ft^2):
Porsche 911 7.3
Saab 9-3 7.6
Porsche 944 7.9
Toyota Camry 8.0
The 911's aerodynamics are actually 10% better than the Camry, and
the 944 about 1%. The 911 is 5% better than the Saab, the 944 about
5% worse.
--- Peter VanDerWal <[EMAIL PROTECTED]> wrote:
Behalf Of Robert Baertsch
Any Porsche experts out there? I hate to sell this car.
-Robert
Robert
I'm doing a 944, similar but different. My reasons should apply
to your
911.
The car is well made, it will handle the additional load of a
reasonable
pack. I'm planning on
around 1000 lbs of cells.
Very good brakes!
Very aerodynamic.
Actually, it's not all that aerodynamic. Kind of middle of the
road
actually.
The Porsche 911 has a Cd of about 0.31 and the 944 is about 0.33
Aerodynamically, a late model Camry 0.28, or a Saab 92 0.29, or
Saab 9-3
0.28 would be a better choice. IIRC the Saab has a better weight
capacity
too.
Of course if you have lots of buck a Mercedes W203 0.27 or W221
0.26 might
be a good candidate.
Best would probably be (if you can find one) and Audi A2 TDI at
0.24 Cd
I was actually a little surprised to find that a Porsche Boxster is
better
than a 911, 0.29 Cd.
This is all from the wikipedia page on drag coefficient:
http://en.wikipedia.org/wiki/Drag_coefficient
so take it witha grain of salt, but I've seen these figure for the
Porsche
elsewhere, so I'm pretty sure they are acurate.
__________________________________________________
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--- Begin Message ---
Is 14.8v tuned for full on or for just starting to blink?
My BS detector is plugged up, so it's hard to distinguish between lore
and fact right now ;)
Mike
--- Rich Rudman <[EMAIL PROTECTED]> wrote:
> Clampers is a term that only you use.
>
> I use 14.80 volts for AGMs. I tune them for 14.8? volts
>
> Some of us just know....
>
> Most AGMs, have a peak cyclic charge voltage speced on the Sticker...
>
> It's a matter of reading the instruction that come on the
> battereis....
>
> And for some of us we have 1.5 decades of abusing AGM lead acid
> batteries...
> The BS detector and years of watching them charge...tells us what we
> need to
> know.
>
> Rich Rudman
> Manzanita Micro
>
> ----- Original Message -----
> From: "Mike Phillips" <[EMAIL PROTECTED]>
> To: <[email protected]>
> Sent: Friday, April 07, 2006 10:50 AM
> Subject: Re: Multi charger.
>
>
> > And a fine invention it is!
> >
> > Tell me why they are not clampers?
> >
> > They really work that well eh? Cool. That assumes that the voltage
> they
> > are set at is correct, right?
> >
> > So what is a correct voltage for AGM for instance? How do you go
> about
> > finding out the correct voltage? Voltage? Boiling point?
> >
> > Thanks,
> >
> > Mike
> >
> > --- Rich Rudman <[EMAIL PROTECTED]> wrote:
> >
> > > They are called Regs...not clampers.
> > > Yes they equalize.. and very well I might add. That's why I
> invented
> > > them.
> > >
> > > I find you more than double the life span with Regs. Maybe even
> by a
> > > factor
> > > of 5.
> > >
> > > Rich Rudman
> > > Manzanita Micro
> > >
> > >
> > > ----- Original Message -----
> > > From: "Mike Phillips" <[EMAIL PROTECTED]>
> > > To: "Rich Rudman" <[email protected]>
> > > Sent: Friday, April 07, 2006 10:05 AM
> > > Subject: Re: Multi charger.
> > >
> > >
> > > > Rich,
> > > >
> > > > Do clampers qualify as equalization? I know that sounds
> obvious,
> > > but I
> > > > still wonder if making the voltage the same on each AGM is
> enough
> > > make
> > > > them last longer.
> > > >
> > > > Mike
> > > >
> > > >
> > > >
> > > > --- In [EMAIL PROTECTED], "Rich Rudman" <[EMAIL PROTECTED]>
> > > wrote:
> > > > >
> > > > > The thread the keeps going here is ... Brutal series charger
> and
> > > > small low
> > > > > power modular chargers.
> > > > >
> > > > > I see the merit there since the little chargers act like
> Additive
> > > > Regs, and
> > > > > of course have thier own voltage regulation and float
> settings.
> > > > >
> > > > > What I am picking on is using the small chargers or low
> quality
> > > 20 amp
> > > > > modular chargers. These seam to have some serious trouble
> with
> > > > reliability.
> > > > >
> > > > > Any path will get the job done.
> > > > >
> > > > > On AGMs you have to have more than just a high power series
> > > > charger.. you
> > > > > have to get the equalization done some how or loose the pack
> in a
> > > hurry.
> > > > >
> > > > > When you can't get a battery to equalize... you other issues
> to
> > > worry
> > > > > about....
> > > > >
> > > > > Rich Rudman
> > > > > Manzanita Micro
> > > > >
> > > > >
> > > > >
> > > > > ----- Original Message -----
> > > > > From: "David (Battery Boy) Hawkins" <[EMAIL PROTECTED]>
> > > > > To: "EV Discussion List" <[EMAIL PROTECTED]>
> > > > > Sent: Thursday, April 06, 2006 2:21 PM
> > > > > Subject: Re: Multi charger.
> > > > >
> > > > >
> > > > > > Rich and All,
> > > > > > Although I agree that people like Bill Dube' had trouble
> with
> > > modular
> > > > > > charging in the past, due to problems with the chargers
> that
> > > John
> > > > Bryan
> > > > > > mentioned, I will say again that my AGM's have been very
> happy
> > > with 16
> > > > > > individual five amp Soneil (1212SR) chargers (and the
> > > > FrankenLesters for
> > > > > 30
> > > > > > amp bulk charging). For poor folks like me, modular
> charging is
> > > > usually
> > > > > our
> > > > > > only option at the moment, and John Bryan was a major
> > > inspiration
> > > > to my
> > > > > > decision to go that route!
> > > > > >
> > > > > > 50,000 plus eelectric miles on the buggies, and a counting,
> > > > > > Dave (B.B.) Hawkins
> > > > > > Member of the Denver Electric Vehicle Council:
> > > > > > http://www.devc.org/
> > > > > > Card carrying member and former racer with The National
> > > Electric Drag
> > > > > > Racing Association:
> > > > > > http://www.nedra.com/
> > > > > > Lyons, CO
> > > > > > 1979 Mazda RX-7 EV (192V of Orbs for the teenagers)
> > > > > > 1989 GM (General Murderers of the EV-1!) S10 (144V of
> floodies,
> > > for Pa
> > > > > only!)
> > > > > >
> > > > > > >From: "Rich Rudman" <[EMAIL PROTECTED]>
> > > > > > >Date: Tue, 4 Apr 2006 10:44:04 -0700
> > > > > > <snippage>
> > > > > > >I still think the Modular chargers have a weak point and
> that
> > > is the
> > > > > Failure
> > > > > > >rate gets multiplied by the number of units running.
> > > > > > >We tried this on this list.. and had some pretty serious
> > > failures...
> > > > > > >
> > > > > > >Making tons of little chargers... has it's merits, but I
> don't
> > > > think it
> > > > > will
> > > > > > >survive the rigors of a on road EV for very long.
> > > > > > <snippage>
> > > > > >
> > > > >
> > > >
> > > >
> > > >
> > > >
> > >
> > >
> >
> >
> > Here's to the crazy ones.
> > The misfits.
> > The rebels.
> > The troublemakers.
> > The round pegs in the square holes.
> > The ones who see things differently
> > The ones that change the world!!
> >
> > www.RotorDesign.com
> >
>
>
Here's to the crazy ones.
The misfits.
The rebels.
The troublemakers.
The round pegs in the square holes.
The ones who see things differently
The ones that change the world!!
www.RotorDesign.com
--- End Message ---
--- Begin Message ---
Hi all,
I'm in the midst of planning an ev conversion of my VW Golf, scheduled for
sometime next spring.
Based on the length of time I plan to keep the car (until the wheels fall
off), the weight advantages, and my general dislike of the idea of replacing
1500+ pounds of batteries every few years, the idea of SAFT's NiCad units is
intriguing. Particularly the water-cooled STM 5-100 MRE's.
I know they're a premium, and I'm willing to front a fair bit of money for
a really, really long service life. However, even after reading several
diaires of conversions using SAFT batteries, I cannot find any hard (or even
firm) price figures for them.
I contacted a local supplier who agreed to get 24 of them for me at
CAD$1295.00 each FOB Georgia. This works out to just over CAD$31,000 for a
144v pack before it even reaches Canada, and that isn't even factoring in
the multi-kilobuck charging system.
Yowza. I cannot imagine that that is the best price, and I strongly
suspect that the supplier is tacking on at least several dozen percent of
margin there, if not much more.
I know there's a few people out there who've used SAFT NiCads in their
conversions, and I do intend to do more price research. The problem is I
really don't know what a good price is. I'm hoping that Someone(tm) will be
able to provide the dollar figure (USD is fine) they paid per unit for a
similar quantity, just so I know what to shoot for.
Any information would be greatly appreciated.
Thank you very much,
Robyn
--- End Message ---
--- Begin Message ---
David Dymaxion wrote:
Don't forget, the important number is Cd*A, Cd = coefficient of drag
and A = frontal area of the car. Using height and width numbers from
<http://www.carpoint.com>, and Peter's Cd numbers, here is a little
table of Cd*A (ft^2):
Porsche 911 7.3
Saab 9-3 7.6
Porsche 944 7.9
Toyota Camry 8.0
The 911's aerodynamics are actually 10% better than the Camry, and
the 944 about 1%. The 911 is 5% better than the Saab, the 944 about
5% worse.
Indeed:
http://www.mayfco.com/tbls.htm
These charts indicate much lower Cd*ft2 numbers for the Porsche line,
BTW. They use manufacturers frontal area specs. I think the width and
height of curvy cars like this leads to gross overestimations of frontal
area. AKA a circle has less area then a square...
Porsche 911 6.27
Porsche 944 6.96
Toyota Camry 7.57
Saab 900 7.10
My personal favorites:
68 Toyota 2000GT 5.76
90 Nissan 240SX 5.88
~ Peanut Gallery ~
--- End Message ---
--- Begin Message ---
Mike Phillips wrote:
For reference, when I added water to my 104 batterys last December it
took several charge/discharge cycles for the additional water to take
effect.
Interesting. Did you have the same symptoms? What weirds me is that
three of the cells went dead with the other three happy as clams. And
why would those cells just act as conductors instead of becoming
resistors (and blowing up spectacularly)?
If it turns out that these cells can be reversed then I will drop the
pack again, and "fix" those 10 volt batteries.
Question: How much water were you adding?
Chris
--- End Message ---
--- Begin Message ---
Jim
Thanks for the motor id, great website. I will not get these motors for a
couple of weeks so I cannot get more details at this time.
When I first thought about the axle, I had the same thought about 5-10mph
but then figured the forklift had 10 inch diameter wheels at 24-36 volts.
Bump this to 22-24 inch wheels at 96 -120 volts and it might be in the ball
park. Maybe a series/parallel switch to higher voltages if the brushed can
take it.
My thought process is always make it simpler. Tie two motors together to a
drive shaft/ differential to tie two wheels together. Maybe I can save a
couple hundred pound with two motors on two wheels. Four motors/four wheels?
I have only built motorcycles so I'm playing with ideas on cars.
Your comments are greatly appreciated.
Jim Husted <[EMAIL PROTECTED]> wrote:
Hey Ray
I had a look at the pics and they are manufactured by Prestolite Electric
(parts are easy to get a hold of). No numbers on the motors so I can't cross
them to the Prestolite number. The pic doesn't show any glimps as to the
condition of the field and armature, but I'd bet they are in good shape. A
single motor would make a good small conversion and a pair should drive EVen a
heavier EV. I doubt the axles will help as they are designed to drive a
forklift 10 mph. IMO those are a pair of nice lift motor to create a EV project
with. Best of luck, hope this helps
Jim Husted
Hi-Torque Electric
Ray Wong wrote:
Has anyone had any experience using these forklift motors in an EV. They are
off a Hyster E40FR fork lift and have a 90deg geared axle mount and a braking
unit. I don't know the gear ratio. Weight of the motor is about 110 lbs and
with axle about 160 lbs.
http://cgi.ebay.ca/ws/eBayISAPI.dll?ViewItem&rd=1&item=7604861153&ssPageName=STRK:MEWN:IT
I am thinking of how to use a pair of these in an EV.
---------------------------------
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--- Begin Message ---
My symtoms list was varied and long.
I bought 8 new 16ah Hawkers, weighed them, then weighed the old 104
16ah Hawkers and compared them. The old Hawkers were brought up to
13.90lbs by adding 5 to 20 ml of distilled water to each cell,
depending on the gross weight of the batt. 624 cells total. 1.75
gallons of water used. An evenings work ;)
This whole exercise has shown me that there is merit in treating each
cell as a separate battery. I don't know if they watch the cell to
cell filling that carefully at the factory. For AGM's this issue is
paramount. Makes me think maybe water should be added when they are
new. Maybe ultrasound can draw a clearer picture of how much water
each cell has in it.
I am going to machine open a couple of the older batts. I'm half
tempted to machine open a new one for comparison.
One thing I have gallons of data on, is that Hawkers are not sealed.
Mike
--- In [EMAIL PROTECTED], Christopher Zach <[EMAIL PROTECTED]> wrote:
>
> Mike Phillips wrote:
> > For reference, when I added water to my 104 batterys last December it
> > took several charge/discharge cycles for the additional water to take
> > effect.
>
> Interesting. Did you have the same symptoms? What weirds me is that
> three of the cells went dead with the other three happy as clams. And
> why would those cells just act as conductors instead of becoming
> resistors (and blowing up spectacularly)?
>
> If it turns out that these cells can be reversed then I will drop the
> pack again, and "fix" those 10 volt batteries.
>
> Question: How much water were you adding?
>
> Chris
>
--- End Message ---
--- Begin Message ---
Hey Ray
The first problem I see is that these motors are probably running in the 3 to
4 thousand rpm range to obtain that 10 mph. So if you were to attempt to get
higher rpms from the hub the motor is in fact going much faster and would blow
out before you got anything desired. Now you'd have one hell of a stump
puller, lmao. I'm sure that there are those out there that could calc you up
the exact speed you'd obtain but remember the armature will only spin so fast
before you'll be stating "There she blows" (and feeling like Captain Bly). Now
I believe those shafts just might have a nice keyed shaft to adapt your own set
up from, but that I guess we'll have to wait and see. If not I believe an ADC
8" shaft would fit with only minor moding to it. Again this is only my two
rpms worth but I feel thats about what those axles will be putting out 8^ )
IMO the cost is easily worth it just for the motors and looking at them alone
they would be a nice pair to obtain and in fact
would cost me that much if I was looking for them through my suppliers. EVen
when a good deal is announced on the list I make a point to not bid on them as
I'd rather see you all obtain them for your project and a belief there is no
reason to drive up the cost of the motor. If in fact these were brought in for
me to buy I'd buy them in a flash for some future mad ass project 8^ P
Anyways hope this helps, and like I said I'd be looking at just the motors.
I just feel this is a bit more gear reduction than you can use, that is unless
you plan on entering tractor pulls, lmao!!
Cya
Jim
Ray Wong <[EMAIL PROTECTED]> wrote:
Jim
Thanks for the motor id, great website. I will not get these motors for a
couple of weeks so I cannot get more details at this time.
When I first thought about the axle, I had the same thought about 5-10mph but
then figured the forklift had 10 inch diameter wheels at 24-36 volts.
Bump this to 22-24 inch wheels at 96 -120 volts and it might be in the ball
park. Maybe a series/parallel switch to higher voltages if the brushed can take
it.
My thought process is always make it simpler. Tie two motors together to a
drive shaft/ differential to tie two wheels together. Maybe I can save a couple
hundred pound with two motors on two wheels. Four motors/four wheels?
I have only built motorcycles so I'm playing with ideas on cars.
Your comments are greatly appreciated.
Jim Husted wrote:
Hey Ray
I had a look at the pics and they are manufactured by Prestolite Electric
(parts are easy to get a hold of). No numbers on the motors so I can't cross
them to the Prestolite number. The pic doesn't show any glimps as to the
condition of the field and armature, but I'd bet they are in good shape. A
single motor would make a good small conversion and a pair should drive EVen a
heavier EV. I doubt the axles will help as they are designed to drive a
forklift 10 mph. IMO those are a pair of nice lift motor to create a EV project
with. Best of luck, hope this helps
Jim Husted
Hi-Torque Electric
Ray Wong wrote:
Has anyone had any experience using these forklift motors in an EV. They are
off a Hyster E40FR fork lift and have a 90deg geared axle mount and a braking
unit. I don't know the gear ratio. Weight of the motor is about 110 lbs and
with axle about 160 lbs.
http://cgi.ebay.ca/ws/eBayISAPI.dll?ViewItem&rd=1&item=7604861153&ssPageName=STRK:MEWN:IT
I am thinking of how to use a pair of these in an EV.
---------------------------------
Yahoo! Messenger with Voice. PC-to-Phone calls for ridiculously low rates.
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Love cheap thrills? Enjoy PC-to-Phone calls to 30+ countries for just 2¢/min
with Yahoo! Messenger with Voice.
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--- End Message ---
--- Begin Message ---
Cor, can you clarify then
Cor van de Water wrote:
A theoretical example:
- battery voltage 100V
- motor running 4000 RPM in 2nd gear with back-EMF 80V
- motor running 3000 RPM in 3rd gear with back-EMF 60V
- motor resistance 0.2 Ohms
- all other (internal) resistances ignored for simplicity
In 2nd gear the motor draws 100 Amp (100V - 80V = 20V divided by 0.2 Ohms)
In 3rd gear the motor draws 200 Amp (100V - 60V = 40V divided by 0.2 Ohms)
Since the voltage delivered to the motor is 100V in both cases, the power
goes from 10kW to 20kW by upshifting from 2nd to 3rd, reducing RPM by 25%.
But the voltage on the motor isn't 100V anymore - you apply
100V on it but it generates 80V of opposite polarity in one case
and 60V in other. So actual voltage "moving" the motor
is only a difference of the two, in this case as you said:
100V applied reduced by 80V BEMF so 20V on the motor left to run it
(2nd gear),
100V applied reduced by 60V BEMF so 40V on the motor left to run it
(3rd gear). Right?
Victor
--- End Message ---
--- Begin Message ---
Rich, do they equalize only if you charge completely?
E.g. id one choose for whatever reason to cycle between
30% and 70% SOC, do your regs do any given that they have
pre-set limits?
Now, I'm not asking whether people should cycle within
that narrow SOC range. I'm only curious how the regs technically work.
Victor
Rich Rudman wrote:
They are called Regs...not clampers.
Yes they equalize.. and very well I might add. That's why I invented them.
I find you more than double the life span with Regs. Maybe even by a factor
of 5.
Rich Rudman
Manzanita Micro
--- End Message ---
--- Begin Message ---
Wayne wrote:
Assuming two identical vehicles, both driven in an identical manner over
identical routes and terrain, identical weather conditions, etc., IOW:
Identical in all respects with the exception of AC (and associated
AC-paraphernalia), which will have the greater range?
Now with regen? Which will have the greater range?
You said identical terrain, but didn't mention what that terrain is.
Flat? Hills? Mountains? Energy recovery due to regen depends on that.
If you're in Texas you gain far less than if you're in Colorado.
I like the idea of regen but if its not cost effective I'm not
married to the idea.
Define cost effective - express value *to you* if regen in dollars,
and marriage decision becomes easy. Problem is to assign a dollar sign
on something not always tangeable is difficult and often subjective.
Victor
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--- Begin Message ---
Rich, do they equalize only if you charge completely?
E.g. id one choose for whatever reason to cycle between
30$ and 70% SOC, do your regs do any given that they have
pre-set limits?
Now, I'm not asking whether people should cycle within
that narrow SOC range. I'm only curious how the regs technically work.
Victor
Rich Rudman wrote:
They are called Regs...not clampers.
Yes they equalize.. and very well I might add. That's why I invented them.
I find you more than double the life span with Regs. Maybe even by a factor
of 5.
Rich Rudman
Manzanita Micro
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--- Begin Message ---
Isn't the goal to get there? If you can charge fast you don't need a long
range EV. You can use a shorter range EV that charges fast. Bruce
Parmenter http://www.austinev.org/evalbum/012.html has a 50 mile range at
55mph. With another one hour charge he could easily go the next 25 miles.
So do you want a load of batteries or spend your money on chargers which
virtually give you the same range. Fast charging of a smaller pack or long
range? The lighter EV is safer, handles better and over a days time can
travel further. LR..........
----- Original Message -----
From: "Robert Baertsch" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Thursday, April 06, 2006 3:42 PM
Subject: Re: 80 miles in a Porsche 911?
Lawrence,
I don't understand what you are saying. Better than what? I'm happy with
overnight charging. Why are you bringing up charging in one hour?
-Robert
Lawrence Rhodes wrote:
The other option is to put in as many agm's as possible & spend your
money on the biggest charger you can or two of them. There are some
people that can do 100 miles with one one hour charge. That might work
better. It's not the range it's the charging time that is the problem.
Lawrence........
----- Original Message ----- From: "Robert Baertsch"
<[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Thursday, April 06, 2006 12:00 PM
Subject: Re: 80 miles in a Porsche 911?
It is a 1980 Targa 911 SC. The suspension in the back is quite
adjustable so that would be fine. I'm concerned about the front
suspension which is not designed for a heavy load.
The ride is already very hard and I'm not sure what will happen when I
load it up.
I think Lithiums would cost over $10K so I'm going to wait until my
first set of AGMs wear out for advanced chemistry. I think batteries
will be much better is 3-4 years.
There is a Toyota Pickup (2500lbs stock/5260lbs converted) on the
evalbum with 40 T105 Trogan (6v 225ah) batteries that claims over 120
highway miles. http://www.austinev.org/evalbum/037.html
Besides I already have 27 12v 110ah AGM sitting in my garage waiting for
a donor. I don't think the Orbitals have that much capacity. If I used
Tony's truck platform with my batteries I should get over 100 miles.
Am I missing something?
To answer Larry's question, I'm looking for 60mph highway speeds for
most of the trip.
-Robert
David Dymaxion wrote:
Not really an expert, but I'm converting one myself. What year is
your donor car?
Compare to some other cars: The super efficient EV1 with roughly 50%
weight in batteries would go about 40 to 60 miles on a charge (1st
gen lead acid batteries) and about 60 to 80 miles on the 2nd gen lead
acid batteries. Real featherfooting and low speeds would get it 100
miles. The Tzero by AC Propulsion claimed a 100 mile range on lead
acid batteries -- but this is a car with no doors, no transmission,
and an expensive AC drive system.
I'd think 80 miles on lead acid batteries is going to be tough. It
would be much easier with advanced chemistry.
Having said that, with 1900 lbs of batteries and a 911, you might
have a shot at it. The 911 is light and the gas motor is heavy. The
aerodynamics are good, it goes surprisingly fast on modest
horsepower. The suspension is fully adjustable, so you can optimize
toe on both axles. You can get race seats, fiberglass bumpers, and
plastic windows and shave off some weight. You could also put on a
belly pan and shave the rain gutters to improve the aerodynamics.
On the flip side, the truck's aero is going to stink, so you'd need
alot of batteries to get it to work.
My guess is it would boil down to the 911 is better for highway work,
and the truck is better for low speed work.
Final thought: This might be a case for a hybrid pack. Do 26
Orbitals, and as many Lithium batteries as you can afford. Have the
Lithium batteries give a steady 50 amps or so to charge the lead
batteries, and the lead handles the high current bursts. You'd be on
your own here, though, as you'd be trailblazing.
--- Robert Baertsch <[EMAIL PROTECTED]> wrote:
I would really like to get 80 miles in the Porsche 911 and I could
fit 26 110ah AGM batteries inside.
Looks like 8 in the gas tank area, 6 across the back seat, 2 on the
floor and 10 in the engine compartment.
The battery weight would be 27x72lbs=1944lbs. I think the awesome
porsche handling will go out the window with a final weight over
3800lbs. I'm now thinking of the small light pickup instead. The
extra weight should be easier to deal with.
Any Porsche experts out there? I hate to sell this car.
__________________________________________________
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http://mail.yahoo.com
--- End Message ---
--- Begin Message ---
General Electric EV-100 SCR Control Forklift EV100
Item number: 7606784790
on e-bay
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--- Begin Message ---
Topping off and shopping at Costco is the best option. You could have a
normal car that will carry 4 & have it look stock instead looking like a
battery carrier. You will spend more on the chargers than the batteries.
Lawrence Rhodes..
----- Original Message -----
From: "Robert Baertsch" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Friday, April 07, 2006 11:24 AM
Subject: best donor car for 2000lb of lead
Hi all,
I'm building a car to go 80 miles on one charge at 60 mph and have decided
to use 26 110ah AGM batteries that weigh 1944lbs.
I bought a 1980 porsche 911SC thinking the aerodynamics and superior
handling would maximize range but after talking with other porsche owners,
I'm concerned that I'm over the design limits of the car (specifically in
the front end). I also don't like the super hard sports car ride.
I have a few options
1) modify the porsche to improve the ride and handle the weight.
or sell it
2) and buy a light pickup (2500 lbs) that can handle the weight.
3) buy a car and cut it half, and make a Tango-clone. {ok, not practical}
Has anyone done research into donor cars and found a car that weighs under
2500 lbs, has good aerodynamics (CD < 0.31) and minimal frontal area.
Please don't try to convince me to buy lithium batteries or other exotic
batteries. I'll buy them when my AGM wear out and the industry has had
time to produce a product. If I don't make my design constraints, I'll
shop at costco while my pack is topping up. We all have to make some
sacrifices for the next generation.
-Robert
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--- Begin Message ---
Victor Tikhonov wrote:
> All this talk about modular charging reliability boils down to the
> level of expertise and execution when you design and build them...
> There is no manufacturer who will guarantee that no unit will
> fail within certain time period.
True; but most industrial power supplies will provide an MTBF (Mean Time
Between Failure) specification. If the MTBF is (say) 100,000 hours, and
you use (say) 25 of them in your EV, then the odds are that you will
have a charger failure every 100,000/25=4000 hours. If you spend 10
hours in each charging cycle, you can charge about 400 times per charger
failure. If you charge every day, that's about one per year!
That's why when I designed the Tango modular charger, I used Vicor
modules. They have a *demonstrated* MTBF of 30 million hours. That is
high enough that we shouldn't expect any charger failures in the
lifetime of the vehicle.
Now, MTBF calculations are rather idealistic. At best, they test a lot
of supplies for a number of years, and tell you the average failure rate
(how many hours per failure). That's a "demonstrated" MTBF. But they
obviously can only test for as many years as the product has been out.
MTBF also assumes perfect operating conditions; no temperature extremes,
no voltage or current spikes, no shock or vibration, no user abuse. You
have to apply correction factors for higher temperatures and other
stress. For example, you typically reduce MTBF by 2:1 for every 10 deg.C
increase in temperature.
Worst-case, MTBF numbers are little more than marketing lies. The
manufacturer knows it takes years of testing on many units to get
meaningful data, and you aren't going to do it. They aren't going to do
it either; in fact, they *can't* do it on a product that just came out
last month. So they give you a *calculated* MTBF. This is little more
than taking the MTBF advertised for the various parts, and adding them
all up. A calculated MTBF gives you a vague idea what the failure rate
might be if there are no design errors or assembly problems.
> one big advantage -- because it is modular, you can replace a failed
> module and keep going -- something you can't do with an inverter.
That's the hope, anyway. In practice, it's equally likely that the one
big inverter and the modular chargers will *both* be out of production
and unfixable a few years down the road. That's the way most things are
being built nowdays.
I'm an old fuddy-duddy. I prefer to use parts that *have* been around
for 10 years or more, and *do* have a demonstrated MTBF. If they've been
around 10 years, it's also more likely that they will *still* be around
in 10 years; so if it breaks, I can get the parts to fix it.
> The art of small chargers has been perfected over years, they are made
> in many millions. When was last time you saw an inline brick-charger
> (which is really SMPS) for your laptop fail?
Actually, rather often. I've had to fix a few. Computer power supplies
in general have a rather high failure rate; dead ones are common. And
that's when they are being used indoors, where they never get hot or
cold or wet or knocked about.
Most consumer battery chargers *are* highly optimized and perfected.
However, they also know that the average person won't use it all that
often. more than a few times a year. They can design for a very low MTBF
and still expect most units to survive the warranty, simply because they
won't be used most of that time.
> Automated enough system can connect a redundant module instead of
> failed one so there is no impact on the charging operation, and
> user can service bad module at any time later - as long as he knows
> about it.
Yes, I agree. That's what I did with my battery balancer. There are two
redundant charging systems, and the vehicle can still be charged and
used with either one of them broken. And, the driver has feedback to
*know* what is happening.
> Unneeded complexity for the sake of fashion should be avoided,
> no question, but if we wouldn't get worthwhile benefits of
> complexity, we'd all keep driving contactor controllers now.
Agreed. As Einstein said, "Things should be kept as simple as possible
-- and no simpler". Too simple is bad, too complex is bad. The challenge
is to find the happy medium.
> Most of the modular chargers people see failing in their EVs will be
> because they adapt cheapest hardware not really meant for the job and expect
> it to perform.
Right! A cheapie charger can last for years if you only use it to
recharge your boat battery a few times a year. But it will be nothing
but trouble if you try to use a dozen of them every day to recharge your
EV.
But if you know what you're doing, you can successfully adapt things for
other uses. Nowdays, it's not uncommon for a laptop to run continuously
off its AC adapter. It may only have to operate at full power once a
month, when you actually did run the battery down. But the adapter does
have to survive being plugged in continuously, delivering say half its
rated power.
So, you could adapt one of them as your modular charger. You might have
to turn down its charging current so it won't overheat, glue down the
heavier parts inside so they don't shake loose from the board, and add
some screening or waterproofing to keep bugs and water out. Basically,
you are doing the extra work that the manufacturer avoided to save
money.
--
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
--- End Message ---
--- Begin Message ---
On 5 Apr 2006 at 14:18, [EMAIL PROTECTED] wrote:
> At least one VRLA manufacturer has told me that if the battery is over
> 40C there is no point in worrying too greatly about temperature
> compensation of the voltage because the battery is being killed anyway.
> That is, no matter how ideally you treat it otherwise, it will still die
> prematurely.
My Force spent its first few years in service at APS. In the Arizona desert
heat, the typical life of a battery pack was about 6-9 months. Granted they
were flooded marine batteries, but the original controller had a current
limit of 150a, IIRC. And that's still pretty abysmal service and
tremendously high per-mile cost.
Battery heating used to be a strategy for winning range competitions.
Keeping the pack at 90 deg F or even higher certainly did improve capacity,
but experience showed that it also had a negative effect on battery life.
David Roden - Akron, Ohio, USA
EV List Assistant Administrator
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--- Begin Message ---
On 5 Apr 2006 at 14:23, [EMAIL PROTECTED] wrote:
> Blue Sky Motors isn't getting the reserve price on
> their Rangers, even the NiMH one.
>
Anyone who's been in the EV world for more than 20 years has seen this cycle
many times. The price of fuel goes up and/or availability becomes limited
>abruptly<, and there's an equally abrupt flood of interest in EVs, with the
concomitant spike in value for used examples. Gradually the cost of fuel
recedes; EV interest and EV prices ebb right along with it.
Long term, the cost of fuel continues to rise. But except for the bubbles
mentioned above, the market mostly absorbs the increase. In fact experience
in Europe shows that a long-term gasoline price even in the $5-6 per gallon
range doesn't generate significant consumer interest in EVs. They remain
too much out of the mainstream to be seen as an alternative and to benefit
from the increased fuel prices.
This is a sort of a chicken and egg proposition. EVs aren't mainstream
because they aren't perceived as an alternative, and they aren't so
perceived because they aren't mainstream. (There are other factors
operating too.)
I suspect that absent aggressive legislative intervention, only long-term
severe inconvenience of fuel purchase (gas lines or rationing) and/or
effective unavailability of fuel will have much effect on long term consumer
interest in EVs and their values as used vehicles.
OTOH, it's interesting and instructive to note the sales success of low-
compromise, high-efficiency ICE vehicles such as the Toyota Prius. These
vehicles are deliberately mainstream and non-threatening to the consumer, so
they can benefit more readily from demand created by increased fuel prices.
David Roden - Akron, Ohio, USA
EV List Assistant Administrator
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