EV Digest 3868
Topics covered in this issue include:
1) Re: Long range EV's, was (FAQ?) DC vs. AC
by jerry dycus <[EMAIL PROTECTED]>
2) Re: Scooter Battery Balancer
by Lee Hart <[EMAIL PROTECTED]>
3) Re: Scooter battery balancer
by Lee Hart <[EMAIL PROTECTED]>
4) Re: What tricks have you implemented to reduce drag? Need ideas.
by "John Westlund" <[EMAIL PROTECTED]>
5) Newbie questions
by [EMAIL PROTECTED]
6) Re: .li-polymer bats.
by "John Westlund" <[EMAIL PROTECTED]>
7) Re: Newbie questions
by "John Westlund" <[EMAIL PROTECTED]>
8) Re: .li-polymer bats.
by David Dymaxion <[EMAIL PROTECTED]>
9) Re: What tricks have you implemented to reduce drag? Need ideas.
by David Dymaxion <[EMAIL PROTECTED]>
10) Scooter Battery Balencer
by Jeff Shanab <[EMAIL PROTECTED]>
11) Re: Interesting motor?
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
12) Re: Curious about PM motor options for EVs
by "Philippe Borges" <[EMAIL PROTECTED]>
13) Re: Scooter battery balancer ( Long, Data, Data)
by "Rick" <[EMAIL PROTECTED]>
14) Air/electric porwer bike
by "The Greens" <[EMAIL PROTECTED]>
15) What tricks have you implemented to reduce drag? Need ideas.
by "Raymond Knight" <[EMAIL PROTECTED]>
16) Re: .li-polymer bats.
by "Steve Clunn" <[EMAIL PROTECTED]>
17) Re: Newbie questions, Scooters an' Bikes!
by "Bob Rice" <[EMAIL PROTECTED]>
18) Re: Newbie questions, Scooters an' Bikes!
by richard ball <[EMAIL PROTECTED]>
--- Begin Message ---
Hi Tommy and All,
--- Tommy Thorn <[EMAIL PROTECTED]> wrote:
> jerry dycus wrote:
>
> > As far as his need for 80-100 mile range I
> forgot
> >about Ni-cads, that a pack of 180 amphr units of
> 96vdc
> >or 156vdc worth of 100 amphr units would get his
> range
> >with room to spare. And about the same weight,
> about
> >$8,000, ie $550kwhr. You need about 15kwhrs. This
is a 20 yr+ life batt.
> pack
> >and well tested tech. Mine are 30 yrs old and still
> >putting out rated power!!
> > The ni-cads won't do 1,000 amps so a cheaper
> >controller could be used.
> >
> >
> Why Ni-Cds when Ni-HMs are so cheap, have higher
> power densities, have
> no memory effect, and are more friendly to the
> environment? I presume
> there's a good reason though.
You are mistaken here. You are confusing small
cells with EV batts probably. Big difference.
Ni'cads are about 1/5 the price of NiMH batts in
EV sizes if you could get them. NiMH don't work well
in heat either.
EV, flooded ni-cads don't have menory effect.
>
> I'll continue lurking for now and attend the events
> that I can. There's
> still a lot I need to learn before committing time
> and money.
That's smart but think about building a lower tech
EV to start with to learn on and use the EV parts of
it to build a better one after you learn more.
Say start with an early MR2 with just Orbitals and
later upgrade to longer range batts. You could do that
for about $4-5k by buying some used parts.
If you buy used for a good price, you could sell
them later for about the same except for the batts.
With 12-13 130amphr 12vdc flooded batts you should
get the range you need in an optimized MR-2. Or more
from 12-16 T105-125 type batts.
jerry dycus
>
> Thanks!
> Tommy
>
>
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--- Begin Message ---
Jeff Shanab wrote:
>
> http://rsise.anu.edu.au/~luke/xr4000batbal.html
>
> how about using a power transistor to "amplify" the current capacity of
> the zener
This works. My first "Rudman regulator" was actually a zener, pot,
transistor, and light bulb. It is wired like this (view with a fixed
width font like Courier New or FixedSys):
+12v____________
| _|_
_|_/ / \ 12v car
13v //_\ \___/ brake lamp
zener | ___|
> B|/ |C
200 ><---| |/ darlington NPN transistor
ohm > |\_| on small heatsink
| |\ MJE1100 or equivalent
1k > |E
ohm > |
> |
-12v__|_________|
The brake lamp draws about 1.6 amps, and serves as a current limiter, so
that's the most this regulator will bypass. The 1.6amp current limit
also means the transistor's power dissipation is no more than about 10
watts, so its heatsink can be relatively small (about 2-3 cubic inches).
The pot sets the voltage at which it starts to bypass current. The 13v
zener makes the minimum regulating voltage about 14v. The 1k resistor is
only needed if the transistor doesn't have a built-in base-emitter
resistor (many darlingtons do).
You can make this sort of regulator work at almost any current. The lamp
can be eliminated, but then the heat produced in the transistor can be
very high. For example, a 15v regulating limit with a 25amp charger
would ask the transistor to dissipate up to 15v x 25a = 375 watts! That
takes a gigantic transistor and heatsink!
--
"Never doubt that the work of a small group of thoughtful, committed
citizens can change the world. Indeed, it's the only thing that ever
has!" -- Margaret Mead
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Rick wrote:
> My scooter has two 10Ah batteries... When the voltage came up to
> 28.85, the red LED went off and the yellow came on. At 29.01 volts,
> the yellow light went off and the green light came on, and the
> battery voltage eventually dipped down to 27.05. After about an
> hour I rechecked and it had come back up to 27.15. I checked the
> batteries individually and found one that was .4 volts below the
> other.
These voltages are interesting, but not very helpful without knowing the
current. Even the 0.4v difference is not particularly meaningful. AGMs
can easily have significant voltage differences at the final stages of
their charging cycle.
> So, I grabbed a 12V "smart charger", wall wart variety with LED's
> and hooked it up to the low battery. This is the charger supplied
> by Ryobi when I purchased my extra 12V 7Ah battery for my cordless
> trimmer. Within about 20 minutes, the wall charger LED had changed
> to green, but the finish voltage was high @ 14.69. I guess that
> explains why my good Powersonic AGM's that I used with my Ryobi
> cordless died so soon... They got baked to death.
Agreed. The charger supplied with almost *all* consumer products is
near-junk that will mindlessly overcharge your batteries. Measure the
actual voltage and current they apply; you will be horrified.
> Well, anyway, my resting voltages this morning are 13.21 and 13.19
> so I guess that it helped.
Are these voltages after the batteries have sat over 12 hours? The
resting voltage isn't usually over 13.1v except shortly after charging
or when the SG (Specific Gravity) is over 1300. An SG that high shortens
life and causes excessive grid corrosion. It usually gets over 1300 as a
consequence of water loss from overcharging.
> Should I run another balance charge on the lower battery before
> using the scooter again, or just do another balance charge after
> the next use?
I'd guess not; you may have done more equalizing than necessary. As a
rule, you shouldn't need to equalize any more than 1-2 times a month.
> When I need it charged quickly, I use my EV Warrior charger. It has
> a bit too much inrush current for 10 Ah batteries IMHO.
As long as the battery is between 25% and 75% charged, you can charge at
any current you like. Just keep the voltage under the gassing point
(2.4v/cell, or 14.2v/12v battery) and the battery will accept only as
much current as it can handle.
> I have charged with it several times, usually I can charge in two
> hours or less with it. The supplied switching supply charger takes
> about 3-4 depending on DOD.
It's *impossible* to fully charge a lead-acid battery in 2 hours -- or
even 3 or 4. You can get it 80-90% charged that fast, but the last
10-20% has to be put in at a much slower rate.
> I use a regulated power supply from RS that I used to charge my
> batteries on the ebike. I can adjust the final voltage internally
> with it. Many good 13.8 volt power supplies have a small trimmer
> pot inside. Constant voltage charging seems to work nearly as well
> as constant current.
Yes, it works just fine. The only drawback is that there is no one
"ideal" voltage that you can do the whole charge at. A low voltage (like
13.2v) takes days to reach full charge. A high voltage (like 14.8v) will
overcharge the battery. An in-between constant voltage will *both* take
a long time to reach "full", and then proceed into overcharge anyway.
This is why multi-step charging algorithms are used.
> I checked the pack... one battery at 8.5 volts, but all the others
> are between 12.17 and 12.13.
Ouch! The one at 8.5v is dead, and probably damaged. The others at
12.13-12.17 are sulfated from sitting near-dead a long time; it will
take many cycles to get them back up in capacity. It would have been
better to charge them occasionally during storage to keep them at or
near full charge.
--
"Never doubt that the work of a small group of thoughtful, committed
citizens can change the world. Indeed, it's the only thing that ever
has!" -- Margaret Mead
--
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
>Depends on the car!!!!!!!!! Some cars are good,
>other well!
I used the coefficient drag, weight, and frontal area
figures provided by the manufactures of respective cars,
which has lead me to investigate how people manage to get
these numbers in efficiency.
>Depending on the car you can do even 20-25%
>reduction in aero drag by the ways you say but each
>model is different.
Wow. This may then give advantage to high drag low frontal
area cars, since drag can be changed, and frontal area
can't. If I could theoretically reduce my Cd down to .33
from .42, I could have 50-60 miles range at 60 MPH, and
overall Cd*A comparable to a stock Honda Insight! (Insight
is frontal area of 18 feet square, coefficient drag of .25,
while a Triumph has a frontal area of 15.5 feet square.)
>You could have picked a more aero car to begin
>with! .42CD is fairly high drag now days. Cut that by
>1/3rd by switching gliders!!
Nothing, except for some kit cars or an MG midget or some
very rare microcars, has a lower frontal area than what I'm
planning. With frontal area factored in, there aren't many
cars more aerodynamic than that glider, even if the Cd is
high. Aside from that, I like the option of a Triumph
Spitfire because of its low weight. It does wonders for
acceleration.
>Not the battery for range!!!!!!!! Floodeds give
>15-25% more range for the weight than AGM's.
>I'd only use them for racing, short range sport or
>a booster pack for li-ions. Not for long range.
I know about floodies giving better range, but since they
lack power, require maintenance, and have sulfation problems
if they go unused for too long, I'll gladly stick with
Exides at the expense of the range. I couldn't hope to get a
sub 12 second 0-60 time with floodies. If I were to go the
flooded battery route, I'd be looking at SAFT NiCds, but
they are too lacking in power. I want to have performance
comparable to some of the hot new cars on the road, like the
Nissan 350Z and Honda S2000, meaning 0-60 of < 7 seconds is
needed. I'm looking at using a Zilla 1k controller and WarP9
motor for some torque! Calculations show an 8-inch wouldn't
give me the torque needed, just in case anyone is ready to
suggest saving 40 pounds.
>What looks like aero to most people isn't!!! It's
>in the details.
Ahh. But I was going with raw numbers, not looks. A 1992 Geo
Metro has an overall Cd*A of 6.8, with its Cd at .36 and
frontal area of 19 feet square, while the Triumph I ran
simulations on has a Cd*A of 6.5.
It has me stumped as to how cars like a Solectria Force
consume < 180 wh/mile at 60 MPH speeds, when comparing the
aerodynamics of both cars stock, and weights, the Triumph
turns out better in both cases. Hence this topic. I figure
extensive modifications had to have been done for people
like John Bryan to be getting energy consumption figures so
low with his Ghia.
If what you say is true, like being able to reduce Cd by
20-25% depending on car through the tricks I looked at, this
is very good news for what I want to do. Decent range and
speed combined may be possible for an affordable price
without going the kit car or custom route. :)
>It sounds like you have a good idea of what's
>needed but you seem to need a different, more aero
>car
>as a starting point like a VW Ghia, early MR2, early
>RX-7, ect.
>Then start your drag reduction from there and
>you'll be happier, go a lot farther.
Actually, the car I am looking at, a Triumph Spitfire, is
more aerodynamic than VW Ghias overall, and about as aero as
MR2s and RX7s overall, meaning frontal area multiplied by
coefficient drag. My frontal area is only 15.5 feet square.
Frontal area could be reduced to 14.9 feet square by
lowering the car, cutting the wind screen down, and building
a hard top, like Triumph did with the GT6. A Triumph
Spitfire has a coefficient drag times frontal area of 6.5,
or .42 Cd times 15.5 square foot cross-sectional area. Cd of
a 70s-80s RX7 is .33, while frontal area is 19 feet square,
which is a Cd*A of 6.3. A VW Karmen Ghia has a frontal area
of 18 feet square and Cd of .4, giving a Cd*A of 7.2. An 80s
Toyota MR2 has a Cd*A of about 5.9.
>Every little bit helps! That's how you do it.
If possible, I'd prefer to shun the LRR tires though. I'd
prefer being able to achive > .9 Gs on a skidpad and having
the traction to handle the 380 lb-ft of torque a WarP 9 is
calaculated to put out with 1,000 amps of motor current. I
want something I can terrorize my city with, while serving
all my transit needs with concern to ecology and
implications of oil use. I never drive more than 50 miles
from home on any given day, and if I did, I'd definately be
thinking of building a biodiesel electric hybrid instead. :)
> That's pretty good, what kind of car is it?
I'm looking at a Triumph Spitfire. They've been relatively
consistant through all model years as far as curb weight and
aerodynamics, at least before they got that ugly rubber
bumper. The heaviest model, the 1980 year, has a glider
weight of 1,380 pounds. I don't know the glider weights of
the other models, but it is sure to be even lighter, without
all that DoT crap put on it to bog it down with weight.
>There is little lighter than wood! My body-frame
>of wood only weighs 250 lbs. In metal it would be
>almost twice that.
>If a convertible, build, buy an aero hard top.
I've thought of wood, but I'd prefer the structural rigidity
of steel or the durability for such low weight of
fiberglass.
Thanks for your reply.
I figure it has got to be possible to get 50 miles usable
range highway on a moderately aero fast car with steady
driving, if the unaerodynamic Blue Meanie on 156V of
Orbitals can get 25 miles range driven in a very spirited
manner. If it comes down to it, however, I will not
sacrifice speed for range, unless I could get 80-100 miles
per charge, and only then if I wouldn't increase the weight
over 2,700 pounds and/or reduce acceleration to anything
slower than 0-60 in 10 seconds. Evertrolls gave me that
attractive option, but they are no longer offered now, so
I'm looking at Orbitals, and will enjoy making use of the
performance they can provide.
I've seen your estimates on how much reducing drag is
possible, I'd love to see other estimates, and peoples
experiences.
--- End Message ---
--- Begin Message ---
Hello all-
I just subscribed to this list, trying to learn a bit about EVs. I'm not
necessarily looking to buy or do an EV car, but with a 4.5 mile commute
(each way) in a warm climate I've been thinking an EV motorcycle might be
a good thing. Can anybody suggest a book that would be a good starting
point for somebody new to EVs? I saw several texts listed on the various
web sites, which is best? Also, any EV enthusiasts in the Memphis, TN
area? Not holding my breath, mind you.
Thanks.
Eric S
Germantown TN
________________________________________________________________
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--- Begin Message ---
>On Li-ions, it's how you do the cells,
>interconnects, plates, ect that set the power
>available just like it does in lead batts.
I know this.
>And as Cliff said, their specs do conform to
>other known li-ion batts mostly so not that hard to
>believe. It's a big battery!!!!
Well, I wouldn't say they conformed, but have many
similarities too. Cliff did have his questions. I don't
think such a battery is impossible. Look what AC Propulsion
did with off the shelf stuff. :)
>Right now it's only the newness of the tech,
>demand, that keeps prices high.
Well duh. ACP quotes mass production figures of LiIon
batteries in the $250/kWh range. Assuming a BMS makes up
15-20% of the cost, a 30 kWh pack in mass production would
realistically be in the $9,000 range, and that's using
figures that are about 2 years old. 30 kWh in an aerodynamic
car like a Prius is easily good for 200 miles range at
highway speeds, viable for a replacement to IC cars and good
for interstate travel. Hell, Doug Korthof claims to have
driven all over the west coast of the US and Canada in his
EVs and they don't even boast that kind of range. :)
>The chemicals were
>just developed and and manufacturing has to ramp up
>and it's about doubling each yr. But they are not
>expensive so should come down fairly quickly as
>manufacturing ramps up. Lets hope so!
I certainly do hope prices come down. It's manufacturer's
claims that I'm always wary of. I don't tend to trust
something unless it is independently tested and used, as any
manufacturer can BS their figures up to make their product
look competitive.
>Between the price of oil, closed over $55 Friday,
>and Bush's stupid economic policies the world economy
>will slow a lot more next yr should relieve demand so
>prices can fall.
Welcome to the world of peak oil. Your stay will surely
suck. Volatile political implications related to oil
addiction in a post 911 world are bound to have a negative
affect, along with demand from industrializing nations and
rapidly rising prices.
Aside from that, I'm not going to comment on Bush on this
list, but I will say my own personal politics are somewhere
between libertarian and green, if that gives you an
indication. Now lets try to keep things related on an EV
note and not stray too far off topic. ;)
On a technological note that is more in line with the list
charter, I'd say this technology is probably viable to enter
the consumer market, given battery specific energys of > 140
wh/kg and specific powers > 500 W/kg having been in the mass
market for years, and said Li Ion batteries can be picked up
off the shelf for $3. It's just a matter of getting people
interested and having them demand that they be offered EVs.
Seeing a comment on this list a while ago, where one member
mentioned he went to a movie theatre and there was some
Toyota commercial that had the punchline at the end, "How do
you like your zoom zoom?", and hearing of an audience member
yelling out "ELECTRIC!" right after, definately put a smile
on my face, and gave me the impression that this technology
is overcoming the odds stacked against it.
--- End Message ---
--- Begin Message ---
>I just subscribed to this list, trying to learn a
>bit about EVs. I'm not
>necessarily looking to buy or do an EV car, but with
>a 4.5 mile commute
>(each way) in a warm climate I've been thinking an
>EV motorcycle might be
>a good thing.
Considering it's not too difficult to get a 40 mile highway
range from an electric car, an EV is certainly doable for
your needs. EV motorcycles can easily get 15 miles range at
highway speeds, well within your reach. Some have gotten
significantly better results, even with such poor
aerodynamics, an EV's nemesis. A motorcycle might be easy on
your budget too, but I'd talk to people that have converted
motorcycles for specifics.
>Can anybody suggest a book that would be a good >starting
>point for somebody new to EVs? I saw several texts
>listed on the various
>web sites, which is best?
I recommend both of the following as a must purchase item:
1) Build Your Own Electric Vehicle, by Bob Brant
2) Convert It, by Mike Brown
The first covers all the calculations and technical
information your average person would be interested in
knowing when it comes to EVs, while the second covers the
conversion process, step by step, in-depth.
Get them both.
--- End Message ---
--- Begin Message ---
Here's another data point:
http://www.saftbatteries.com/130-Catalogue/PDF/VLP.pdf
Saft says these lions will do 1.3 kW/kg (similar to the Kokam and
Splendid LiPo)! An Orbital battery will do about 0.7 kW/kg at most,
about 1/2 of these lithiums. Imagine 1/2 Megawatt of batteries
onboard (about 500 hp to the wheels!). Too bad they cost so much.
--- Steve Clunn <[EMAIL PROTECTED]> wrote:
> I just got this E mail from Paul the guy who makes the kit cars ,
> http://www.paulsexotics.com/Electric%20car%20conv.htm
> they Sound to good to be true to me, with a 4000 amp continuous
> discharge
> Maybe Lawrence has also been dreaming about batteries :-)
> Steve Clunn
>
>
>
>
> Advanced Battery Factory(Sino-America Joint Venture)
>
> Add: JinXiu JiangNan, Shen Zhen, Guang Dong Province, China.
>
> Phone: 86-133-5290-6882( 24 hours a day, 365 days a year)
>
> FAX: 86-755-2806-9219
>
> Website: www.splendidbattery.com e-mail: [EMAIL PROTECTED]
>
> Specification Sheet of Li-polymer Battery Pack 148V/400Ah
>
> Main application: electric-vehicle and military applications
>
> Li-polymer battery 148V/400Ah
>
> Max. continuous discharging current
> 4000A
>
>
> Max. continuous power
> 673Kw
>
>
> Max. pulse discharging current
> 5000A for 3 second.
>
>
> Max. pulse power
> 840 Kw
>
>
> Max. recommend continuous charging current:
> 400A (for 14.8/400Ah)
>
>
> Total weight
> Approx. 400Kg
>
> (While the weight of lead acid battery
>
> 148V/400Ah is about 1600Kg!!!!!)
>
>
> Total Volume:
> Approx. 1.2CBM
>
>
> Lowest cut-off-voltage controlled by BMS
> 108V
>
>
> Highest charged voltage controlled by the built-in BMS:
> 170V
>
>
> Highest temperature battery can tolerate
> 90?
>
>
> Self-discharge
> Less than 3% per month.
>
> Internal resistance upon fully charged
> Less than 15 mili Ohme.
>
> Cycle life
> More than 1500 cycles with 60% DOD
>
> More than 1200 cycles with 80% DOD
>
> More than 1000 cycles with 100% DOD
>
> DOD-depth of discharge
>
> Wrapping
> Durable silicon rubber and with color white, pink, red, yellow,
> blue,
> purple, black etc. available
>
> Safety:
> No fire, no explosion, no smoke, no short-circuit .
>
>
>
>
>
=====
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--- Begin Message ---
The Insight and the Coconni's Honda covered the rear wheel wells.
When Porsche put a cover under the rear part of the 944 (a bellypan
behind the rear wheels), it was reported it reduced aero drag by 10%.
In addition to cutting down your windshield, you might be able to
rake it back further, too. Safety would dictate putting in a roll bar
if you do this (and it is a good idea in a convertible anyway).
You could check out what the Land Speed racers do. Here are some
common tricks:
Smooth hubcaps (be careful brakes won't overheat)
Lowering the car
Taping up seams
Narrow tires
Air dam and side skirts
Chop top
Remove right side rearview mirror
Make left side mirror small
Shave the door handles
Shave off the rain gutters
Remove radio antenna
Shorten bumpers if they stick out past the sides
--- John Westlund <[EMAIL PROTECTED]> wrote:
> I hear often of people on this list and elsewhere claiming
> how their EV gets 200 wh/mile or less at 60 mph speeds, with
> these vehicles being cars like Geo Metros and Ford Escorts.
> Then of course, there is Cocconi's CRX of long ago, going ~
> 100 miles per charge at highway speeds on 1,260 pounds of
> Optimas. Or the Solectria Force, having consumption levels <
> 180 wh/mile at highway speeds.
>
> Going through calculations, this doesn't at all possible
> with a fully stock body.
>
> So is this merely bragging, or have people performed
> significant aerodynamic mods on their cars?
>
> And if the latter, what tricks have members of this list
> used to decrease aerodynamic drag?
>
> I've heard of full belly pans and have studied the tricks
> mentioned in "Build Your Own Electric Vehicle", such as
> covering the grille of the car and using a file to round off
> any rough edges, but it doesn't seem like that would have
> such a drastic effect on vehicle aerodynamics. Maybe reduce
> the coefficient drag an extra 10% overall.
>
> What about reducing brake drag and steering drag? How have
> people done this, as it appears this has a nasty habit of
> heavily eating away at range.
>
> I'm curious to know what sort of body, brake, and steering
> modifications people have done to their EVs to eek out more
> range, and for any guesses on how drastic an outcome these
> modifications have had. On top of that, I'd be curious to
> know how much it would cost to undertake said modifications.
>
> I'd love nothing more than to be able to get energy
> consumption down to under 200 wh/mile at 60 mph speeds, and
> have even greater efficiency slowing down just a little, if
> the need arises. So far, my calculated efficiency, assuming
> a Cd of .42, frontal area of 15.5 square feet,
> brake/steering drag coefficient of .0041, curb weight of
> 2,600 pounds, and tire rolling resistance coefficient of
> 0095, is between 260-280 wh/mile at 60 MPH. Reducing this
> would drastically improve range and somewhat improve 1/4
> mile time. With a lower current draw, it would also
> positively affect the amount of usable Ah I have in the
> battery pack I'm looking at, given Peukert's effects. Since
> I'm planning on using 20 Orbitals, every buit of efficiency
> I can squeeze out counts.
>
> But 260-280 wh/mile seems a bit much for such a small car
> and with aerodynamics better than what Geo Metros and Jet
> Electrias have stock. Low rolling resistance tires with
> coefficients of rolling resistance of about .007 would only
> reduce this consumption by 15-20 wh/mile.
>
> What about reducing weight? My glider weight is going to be
> about 1,380 pounds with only removing the ICE-related
> components and their ancillaries. I intend eventually to use
> a fiberglass LeMans bonnet, fiberglass doors, fiberglass
> trunck, and lightweight replacements for glass windows. But
> before then, what can I do? I'm looking at removing any and
> all sound deadener, removing the stock seats and replacing
> them with lighter ones, and fabricating a custom interior as
> I do not like the wood panel dash, and want something at
> least a little lighter and more bare. I figure through
> eliminating sound deadener and changing seats/trim alone, I
> can siphon off 75-100 pounds or so.
>
> Anything in particular that I should keep my eye on when it
> comes to weight, however? I've noticed that somehow,
> conversion companies manage to get EVs to be 400-500 pounds
> lighter than the hobbyists manage. There has to be some
> trick they are using, or perhaps custom parts.
>
> If I can get the horsepower requirements at 60 MPH < 15
> horsepower, I'd be set for some decent range.
=====
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Yes and no.
Not with this circuit, but the lee hart battery balancer is non-disipative.
http://www.geocities.com/sorefeets/balancerland/intro.htm
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Seems simular to the ETEK. I bet it's more than $350.00. Lawrence
Rhodes......
----- Original Message -----
From: "richard ball" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Saturday, October 23, 2004 6:34 AM
Subject: Re: Interesting motor?
great , just after i buy a new etek motor better things turn up
my etek bike project is however coming along nicely and should be on the
road for the spring if it ever stops raining here in wales
incidentaly i have give up on the curtis controller and have ordered a
alltrax instead
regards
richard
bholmber <[EMAIL PROTECTED]> wrote:
I was surfing along for information on E-tek motors and ran across this
battle bot site. Apparently there is a German company (PERM motor) that
builds motors comparable to Etek weight and size, but are rated for a lot
more power. Here are some of the specifications:
Perm Motor PMG 132 Specifications:
Voltage: 24-72 V
Weight: 24.8 lb
Angular-velocity constant: 50.2 rpm/V
Torque constant: 27 ozf.in/A
Terminal resistance: 0.025 Ohm
No-load current: 6A
Rotor Inertia: 1370 oz.in2
Inductance: 19 ?H
Continuous current: 110 A
10 minute current: 200 A
Terminals: 8 mm
48 V Performance
Peak efficiency: 86 %
Peak power:* 15.1 hp
No-load angular velocity:* 2380 r/min
Stall current:* 960A
Stall torque:* 25600 ozf.in
72 V Performance
Peak efficiency: 88.6 %
Peak power:* 34.3 hp
No-load angular velocity:* 3590 r/min
Stall current:* 1440 A
Stall torque:* 38500 ozf.in
Pretty detailed information in PDF format is available at
http://www.robotcombat.com/marketplace_motors_perm.html
Also look at the Perm Motor PMG 080...4hp from a 7.5lb motor.
Hopefully this isn't a repeat...anyways, it was the first I had seen of
these motors. I'm getting pretty interested in doing a motorcycle
conversion now.
Any thoughts?
Brett
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The more powerfull version i know about is AVT SuperMotor and far from 100kW
>>>
Up to 35-kW intermittent power and a continuous rating of up to 20-kW can be
achieved with the unique AVT SuperMotor. Safe speeds of up to 6500 rpm at
voltages up to 120 volts are possible.
>>>
Still one each wheel would be impressive on light car i think.
Controler must have sort of "diferential" feature to let the car take
curves...
http://www.avt.uk.com/page10.html
Philippe
Et si le pot d'échappement sortait au centre du volant ?
quel carburant choisiriez-vous ?
http://vehiculeselectriques.free.fr
Forum de discussion sur les véhicules électriques
http://vehiculeselectriques.free.fr/Forum/index.php
----- Original Message -----
From: "John Westlund" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Sunday, October 24, 2004 1:18 AM
Subject: Curious about PM motor options for EVs
>
> Anyone know of permanent magnet DC motors used in hobbyist
> conversions, and if so, where can I get them? I'd love to
> know the options available, if any.
>
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Lee Hart wrote;
>These voltages are interesting, but not very helpful without knowing the
>current. Even the 0.4v difference is not particularly meaningful.
Hi Lee,
I'm doing a charge cycle on two of the 12V 7Ah AGM's from my bike, using the
scooter charger. I hooked a 12 volt trouble light with a small flashlight
type bulb to each battery for about 2 minutes just prior to hooking to
charger. I monitored the voltage and I stopped the light when voltage hit
11.89 on each battery.
Initial voltage of both batteries was 12.15, initial current in FAST mode
was 1.90 A and on SLOW was 1.18 A. Time was 10:50 PM local.
>Are these voltages after the batteries have sat over 12 hours? The
>resting voltage isn't usually over 13.1v except shortly after charging
No, more like 8-9 maybe 10 hours tops.
>As long as the battery is between 25% and 75% charged, you can charge at
>any current you like.
What is the rule on what voltage equates to 25% charged and does it vary
according to size or difference between SLA AGM's and flooded Pba's?
I have figured 11 volts to be fully discharged on my batteries on the bike
and the scooter both. ???
>you shouldn't need to equalize any more than 1-2 times a month.
Good, last night was the first time I had taken the time to do it since I
got the scooter in late May.
>It's *impossible* to fully charge a lead-acid battery in 2 hours -- or
>even 3 or 4. You can get it 80-90% charged that fast, but the last
>10-20% has to be put in at a much slower rate.
I should have stipulated that within a couple minutes after shutoff, even
after my longest rides, the voltage on the pack has never been below 24.5
volts, so it may be that I'm timing something less than a ~full charge~ .
These are very small batteries, rated 10 Ah, but only about 1/4 inch higher
physically on the outside than a 7 Ah AGM. And I usually am pretty
conservative on the throttle and stay within +/-20% of the rated range per
charge. That's 5 to 10 miles. I only pushed the envelope to ten miles on one
ride, and ran at about 12 MPH nearly the entire ride, 150 pound rider,
suttle inclines but mostly flat streets here in Phoenix.
Nonetheless, I will inform my batteries and chargers that they can't charge
that quickly. ;-)) lol Reality is weirder than fiction isn't it? Especially
when you figure in inexpensive imported chargers.
>Yes, it works just fine. The only drawback is that there is no one
>"ideal" voltage that you can do the whole charge at. A low voltage (like
>13.2v) takes days to reach full charge. A high voltage (like 14.8v) will
>overcharge the battery. An in-between constant voltage will *both* take
>a long time to reach "full", and then proceed into overcharge anyway.
>This is why multi-step charging algorithms are used.
So, are you saying that I should turn the voltage down a bit and that should
be better? I know the BEST fix would be to buy a real charger, but I already
have hopefully a couple now that are smart chargers, albeit that they may be
a bit crude in algorithm parameters.The current I measure after the 13.8 V
mark is way under 100 mA, and it drops to just under 50 mA after 14 volts.
When I used to ride my ebike 10 miles, I had to wait about 10 hours for the
14 Ah buddy pair to charge up, with the current falling below just 500 mA on
the analog meter. I don't remember what the voltage was. I haven't adjusted
the voltage pot inside the power supply though.
I measured the voltage and recorded it back in 2003 and all batteries were
reading 14.44-14.46 V, that was after a couple days on the power supply. I
believe that was the last time I rode the bike or charged the batteries.
>Ouch! The one at 8.5v is dead, and probably damaged. The others at
>12.13-12.17 are sulfated from sitting near-dead a long time; it will
>take many cycles to get them back up in capacity. It would have been
>better to charge them occasionally during storage to keep them at or
>near full charge.
Oh, no argument there! That is the one that made the pack feel sluggish
after I had ridden about a quarter of a mile in 2003. I have never let the
batteries sit near dead for a long time, other than in between charges and
rides. What I mean is, when I was riding I would charge immediately after
each trip. It has sat unused for the most part the last 2-3 years. I'll try
working them back a little bit at a time, but the worst news is it was my
first $100.00 worth of batteries. I got off cheaply.
I have noticed something that would confirm your theory about the sulfation.
The two batteries I'm charging now (have been on for one hour at this point
in real time as I type) have some cells that feel puffed out as I run my
hand along the sides of the cases. Within 5 minutes of my initial hookup,
the yellow light came on, which made me think that one or more individual
cells may have come up too quickly in voltage. I disconnected the charger,
unplugged it to clear the flashing green LED error code and after about two
minutes hooked up again. All seems to be on track again and the voltage is
rising slowly as one would expect. The voltage is up to 28.5 and the current
is still at 1.18 A. I think that's wrong. I think that is way too much, even
for two 7Ah AGM's. My 13.8 volt supply would have scaled back to less than
200 mA by now.
I just checked the voltage again as I went by on "dog patrol", it was at
28.58. Thrity seconds later I heard a click and looked over and the yellow
LED was on. The voltage had just come up to 28.59 and the current was still
ripping along at over an amp! (Rudman likely needs O2 right about now from
laughing so hard LOL)
I aborted the charge cycle, pulled the wall plug. Time; 12:20 AM Local. So,
we now have a better idea of what is going on with the scooter batteries.
The factory supplied charger is roasting them slowly, but surely. I bet the
only thing that has saved this pack so far is the couple dozen charge cycles
that I used the EV Warrior charger. I also opened the case of the Currie
charger and it has a small potetiometer on the main board. Perhaps that
would help settle the voltage down a bit and help prevent gassing on finish
voltage, although at over an amp, I can't see where the cycle is cutting
back. But, at least I might get it to not take the 24 volt pack above 28.4
volts before the green light comes on and goes into stand-by mode.
Thanks Lee, I'm going to bed now before I fall asleep in the chair.
Regards,
Rick
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http://www.china.org.cn/english/2002/Dec/52119.htm
Thought this might be interesting.
Sniper8052
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Using Opera's revolutionary e-mail client: http://www.opera.com/m2/
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To reduce weight and drag, the first two places I would look are the rear
and side glass panels. If the vehicle is older there might be over a 100
pounds just there. I wouldn't touch the windshield though. It is against the
laws in some places, and is just plain inconvenient.
Covering in the grill will have a huge impact on drag efficiency. Building a
belly pan will help a lot as well. But for safety concerns I would make sure
you are creating a low pressure (vacuum) when you do so. In other words make
the sides closer to the road than the middle. If you make it smooth and
even, you run the risk of turning yourself into an airplane wing. By
creating suction underneath, you will force the car to hug the road. Rear
wings can help a lot with drag, as they can clean up the air as it exists
off your car.
If you have removed 500lbs of ICE and tranny, and are only replacing it with
a 100lbs of electric motor, you can look at lightning the front end
components. Replacing them with alloy aluminum or chrome moly parts.
Plexiglass headlight covers can make a big difference as well, believe it or
not. Basically anything that smoothes out the front of your car. I am going
back a lot of years, but I think I remember this accurately. A Firebird had
a 10% difference in efficiency between having its headlights up or down.
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>
> This is very close to something I was looking to do. I took a look at the
site, and I have to
> wonder, are these numbers right? Here a blurb from the site;
>
>
> Can he do all this? 13 AGMs, 50 mile range, 85 mph, 20 min charge to 85%
>
Hi Dave , I've talked to Paul about the 50 miles range as I did the
conversion work . The car is very light 2240 lbs I belive, about the same
weight as John's Blue Meannie . I think at about 20 mph its using 15 amps ,
so 50 miles could be done , but real world driving would be 20 or 30.
> And what will the price be with the Li-Ion upgrade?
>
>From his web site it sounds like there are Li Ion cars on the show room
floor :-) , I told him to get one battery and I'll test it and get to know
it , .
> I hope it's possible because I'm trying to do the same but with an AC
system (higher voltage, more
> batteries) to take advantage of regen. And I can't afford to use a 911
donor.
>
He used a older 912 which was very very light , then the fiber glass body ,
Steve clunn
> Dave Cover
>
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----- Original Message -----
From: "John Westlund" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Sunday, October 24, 2004 1:11 AM
Subject: Re: Newbie questions
> >I just subscribed to this list, trying to learn a
> >bit about EVs. I'm not
> >necessarily looking to buy or do an EV car, but with
> >a 4.5 mile commute
> >(each way) in a warm climate I've been thinking an
> >EV motorcycle might be
> >a good thing.
>
> Considering it's not too difficult to get a 40 mile highway
> range from an electric car, an EV is certainly doable for
> your needs. EV motorcycles can easily get 15 miles range at
> highway speeds, well within your reach. Some have gotten
> significantly better results, even with such poor
> aerodynamics, an EV's nemesis. A motorcycle might be easy on
> your budget too, but I'd talk to people that have converted
> motorcycles for specifics.
>
> >Can anybody suggest a book that would be a good >starting
> >point for somebody new to EVs? I saw several texts
> >listed on the various
> >web sites, which is best?
>
> I recommend both of the following as a must purchase item:
>
> 1) Build Your Own Electric Vehicle, by Bob Brant
> 2) Convert It, by Mike Brown
>
> The first covers all the calculations and technical
> information your average person would be interested in
> knowing when it comes to EVs, while the second covers the
> conversion process, step by step, in-depth.
>
> Get them both.
> Hi All;
For you EV Bikers , an' wannabees, Check out Megawatt Motorworks book
section, from ther EV Chopper guy,Tom Bidwell, he has a nice volume on
building/converting bikes, in the Denver Area. In my Woodburn cross country
oddesy I got a ride on some that Tom had built. Like if yur in the Denver
area? The E Chopper was great! EVen with my 280lb ass aboard it ran at
traffic speeds for around town. Just what yur looking for? He sells the
plans, I believe.The bike handled well, fior me, not a regular bike rider
and it was light years ahead of the chinesy scooters out there. BTW in
National Wholesale Liquidaters, yesterday, I saw a very nicely done Chinesy
scooter, not a bored scooter but a Honda Spree size one, only 399bux, they
only had one with a buncha "do not touch "signs on it. Finding anybody that
knew anything about it... forgetaboutit! Hell, finding any of the help there
that EVen spoke basic ENGLISH woulda been a challange! Traintime was
approaching, so had to run! Check it out another day.
Happy hunting!
Bob
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i bought the el chopper plans
well worth it
my e bike is now nearing completion
regards
richard
Bob Rice <[EMAIL PROTECTED]> wrote:
----- Original Message -----
From: "John Westlund"
To:
Sent: Sunday, October 24, 2004 1:11 AM
Subject: Re: Newbie questions
> >I just subscribed to this list, trying to learn a
> >bit about EVs. I'm not
> >necessarily looking to buy or do an EV car, but with
> >a 4.5 mile commute
> >(each way) in a warm climate I've been thinking an
> >EV motorcycle might be
> >a good thing.
>
> Considering it's not too difficult to get a 40 mile highway
> range from an electric car, an EV is certainly doable for
> your needs. EV motorcycles can easily get 15 miles range at
> highway speeds, well within your reach. Some have gotten
> significantly better results, even with such poor
> aerodynamics, an EV's nemesis. A motorcycle might be easy on
> your budget too, but I'd talk to people that have converted
> motorcycles for specifics.
>
> >Can anybody suggest a book that would be a good >starting
> >point for somebody new to EVs? I saw several texts
> >listed on the various
> >web sites, which is best?
>
> I recommend both of the following as a must purchase item:
>
> 1) Build Your Own Electric Vehicle, by Bob Brant
> 2) Convert It, by Mike Brown
>
> The first covers all the calculations and technical
> information your average person would be interested in
> knowing when it comes to EVs, while the second covers the
> conversion process, step by step, in-depth.
>
> Get them both.
> Hi All;
For you EV Bikers , an' wannabees, Check out Megawatt Motorworks book
section, from ther EV Chopper guy,Tom Bidwell, he has a nice volume on
building/converting bikes, in the Denver Area. In my Woodburn cross country
oddesy I got a ride on some that Tom had built. Like if yur in the Denver
area? The E Chopper was great! EVen with my 280lb ass aboard it ran at
traffic speeds for around town. Just what yur looking for? He sells the
plans, I believe.The bike handled well, fior me, not a regular bike rider
and it was light years ahead of the chinesy scooters out there. BTW in
National Wholesale Liquidaters, yesterday, I saw a very nicely done Chinesy
scooter, not a bored scooter but a Honda Spree size one, only 399bux, they
only had one with a buncha "do not touch "signs on it. Finding anybody that
knew anything about it... forgetaboutit! Hell, finding any of the help there
that EVen spoke basic ENGLISH woulda been a challange! Traintime was
approaching, so had to run! Check it out another day.
Happy hunting!
Bob
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