EV Digest 3999
Topics covered in this issue include:
1) Re: I need Nicad batteries
by Victor Tikhonov <[EMAIL PROTECTED]>
2) long life gels, re: About to purchase batteries
by "Doug Hartley" <[EMAIL PROTECTED]>
3) Chevy Electric S-10s For Sale
by "EV Challenge" <[EMAIL PROTECTED]>
4) Re: long life gels, re: About to purchase batteries
by Andrew Letton <[EMAIL PROTECTED]>
5) Re: About to purchase batteries
by "Raymond Knight" <[EMAIL PROTECTED]>
6) Re: long life gels, re: About to purchase batteries
by "Doug Hartley" <[EMAIL PROTECTED]>
7) Re: wire cutting machine (OT)
by "Lawrence Rhodes" <[EMAIL PROTECTED]>
8) planetary gears
by "steve ollerton" <[EMAIL PROTECTED]>
9) Re: planetary gears
by Reverend Gadget <[EMAIL PROTECTED]>
10) Re: planetary gears
by "Ryan Stotts" <[EMAIL PROTECTED]>
11) Sundancer whereabouts?
by "Ryan Stotts" <[EMAIL PROTECTED]>
12) Re: Jeep EV (Battery LED, Raptor controller questions)
by Otmar <[EMAIL PROTECTED]>
13) Re: planetary gears
by Reverend Gadget <[EMAIL PROTECTED]>
14) Re: Jeep EV (Battery LED, Raptor controller questions)
by Nick Viera <[EMAIL PROTECTED]>
15) Re: long life gels, re: About to purchase batteries
by Seth Allen <[EMAIL PROTECTED]>
16) Re: Jeep EV (Battery LED, Raptor controller questions)
by Nick Viera <[EMAIL PROTECTED]>
17) Interesting quote from the past
by "Ryan Stotts" <[EMAIL PROTECTED]>
18) Re: I need Nicad batteries
by "John Westlund" <[EMAIL PROTECTED]>
19) Re: Follow-up on Valence Li-Ion batteries in 12V size
by Victor Tikhonov <[EMAIL PROTECTED]>
20) Re: AC musings
by Jude Anthony <[EMAIL PROTECTED]>
21) Re: Follow-up on Valence Li-Ion batteries in 12V size
by Victor Tikhonov <[EMAIL PROTECTED]>
22) RE: The Amazing Little Hawkers.
by "Roger Stockton" <[EMAIL PROTECTED]>
--- Begin Message ---
John Westlund wrote:
I'd go SAFT, if they had more power, but they
don't. 250 amps for a 6V nominal battery will simply not cut
it. If it was a 12V battery and it remained fairly stiff at
that draw, then I'd be giving them a look...
Whether it will "cut it" depends on the controller.
In my case very peppy EV does not draw more then 100A
for 99% of the time. In fact, inverter is limited
to 280A but this is 100kW of power. More than enough for
any normal EV.
As of many 6V cells to water, SAFT uses automatic watering
system with water running from one cell to another following
electrical connection. I use 3.6V LiIon cells, about twice
as many as 6V NiCds I'd need for the same voltage.
Of course no need to water them, but in terms of interconnecting,
iti s not that bad, and - one time deal. I've done 160 caps
in series - not too bad either.
Victor
--- End Message ---
--- Begin Message ---
I received an email from my fellow early 90's electric Skoda hatchback
driving friend Carlo, from Germany, this afternoon. It included the
following, of interest to some on the list:
i hope your ts li-ion batts will live long and prosper -my lead-gelled cells
now at nearly 63000km .slow, but stable.
It seems I under-estimated the distance he has added in the last year. At
about 30 km per charge average, that would be 2100 charge/discharge cycles!
Amazing, especially considering this is only an 84V car, with only 14 of the
GC size 6V 160 Amp-Hr Varta batteries. Consequently, each battery has to
provide more current and a higher percentage of the energy to move the car
that 30 km than would each of the higher Amp-Hr rated flooded GC batteries
in a typical 20 battery, 120V conversion, (driven the same way at the same
speeds). It shows also that Carlo is a skillful, conservative EV driver.
Note: these batteries are all still working well and there have been no
failures. Considering that he bought this set of surplus batteries several
years ago because it was the cheapest option for him, I would say that he
more than got his money's worth!
A comment about how he likes his Skoda, now that he has recently aquired
several other EVs also:
i think i should hold the skoda by my side;a better car i had never
before-and they were all non-electric!
I asked him how he liked having regen braking, now that he has installed the
same model controller (Curtis 1221R) that I use in my two Skodas:
regen on my skoda?? i love it! !the most times i can slow down without
mechanical brake.
Best Regards,
Doug
----- Original Message -----
From: "Doug Hartley" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Sunday, January 02, 2005 11:40 PM
Subject: Re: About to purchase batteries
Gel can go over 1500 charge cycles, according to the very positive
experience of my friend in Germany who has the same Skoda 84V car as I
have, using 14 6V Varta 160 Amp-Hr. batteries and no regulators. The
charging voltage typically has to be set lower for gel than for AGM or
flooded, so as not to damage them.
Regards,
Doug
----- Original Message -----
From: "Don Cameron" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Sunday, January 02, 2005 10:15 PM
Subject: About to purchase batteries
After a number of months of investigation, I am about to purchase
batteries.
However, I still am unsure of which battery to purchase. Here are my
vehicle
specs:
- New Beetle (est. curb weight 3700 lbs)
- Siemens AC system
- 312-332 Volts
- 26-28 batteries
- Approx 1000 lbs available for batteries
- Estimate no more that 200 Amp current draw
After a **lot** of analysis, I have boiled it down to two batteries:
Hawker Genesis G42EP
* VRLA AGM
* 42 Amp Hour
* 33 lbs each, 925 lbs for the pack
* $3700 for the pack
* AGM is more sensitive to charging, requires BMS
* AGM delivers power - no problem
* 500 lifecycles
* AGM is common use by many EVers, and is recommended
Deka Dominator 8G34
* VRLA Gel
* 60 Amp Hours
* 42 lbs each, 1190 lbs for the pack (somewhat heavy)
* $3000 for the pack
* Gel is more tolerant to pack imbalances, but still benefits with a BMS
* These have been used in many vehicles by Solectria with lots of success
* Gel cannot deliver much more that 200-250 Amps - but still OK for high
voltage AC
* 500-900 lifecycles
* Gel is not preferred by many EVers on the list
I really prefer the Gels - in theory. They should provided enough power,
last longer, be less affected by balancing issues, thus being much more
cost
effective. But I am concerned that I will simply be buying a battery
based
on spec - not reality. I have asked a number of Solectria users about
their Deka Gel batteries and have received all positive feedback.
Thoughts? Comments?
thanks
Don
P.S. I have not listed the Optimas or the Orbitals because they just are
too heavy/bulky and just won't fit into the vehicle
Victoria, BC, Canada
See the New Beetle EV Conversion Web Site at
www.cameronsoftware.com/ev/
--- End Message ---
--- Begin Message ---
The EV Challenge has several electric vehicles that we are planning on
selling. Over the next month or so the vehicles will be listed on ebay.
Two of the vehicles, which have been used primarily as display vehicles and
in community ride-n-drive demonstrations, are in excellent operating
condition! These are not conversions or vehicles manufactured by companies
which are no longer in existance, but were designed and built by Chevrolet
in the late 90s as electric vehicles. Sold primarily to utiliites and
governments, most of the Chevrolet Electric S-10s were bought back by
Chevrolet several years ago, making these vehicles very desirable. Both
vehicles have been checked by the local Chevrolet EV service center and
found to be in excellent operating condition. One of the vehicles has a
lead-acid battery pack and the other a rare nickel-metal hydride pack. Both
are equipped with Magna-Charge inductive charge ports, a heat pump based
climate control system, auxilary diesel fuel heater, cruise control, power
steering, 4 wheel anti-lock power brakes, regenerative braking, and dual
air bags.
If you are seriously looking a OEM electric vehicle that is ready to be
driven and used on a day to day basis, you may want to consider one of these
vehicles.
Funds raised from the sale of these vehicles will be used to further the
goals of the EV Challenge education program. For a decade, the nationally
recognized EV Challenge has been introducing students and the communities
they live in to the important environmental, energy and economic issues
associated with alternative transportation fuels. Each year thousands of
high school students experience a unique opportunity to design and convert
gasoline vehicles to electric power, while middle school students design and
build model solar race cars.
The EV Challenge is conducted by the non-profit Carolina Electric Vehicle
Coalition.
The links below are to Chevrolet S-10 Electric vehicle reviews and test
results posted on the web including US DOE EVAmerica test results. There is
even a link to a article describing how the trucks were built.
http://www.autoworld.com/news/chevrolet/ElectricPickup.htm
http://avt.inel.gov/pdf/fsev/eva/s10.pdf
http://avt.inel.gov/pdf/fsev/eva/chvs10.pdf
http://www.autofieldguide.com/articles/079701.html
If you are interested and have questions, etc. please feel free to contact
me at [EMAIL PROTECTED]
--- End Message ---
--- Begin Message ---
63000km from a set of used batteries? That's just about unbelievable;
could that be a typo? Could he have meant 6300km? Even 6300km would be
good for a set of used batteries.
cheers,
Andrew
Doug Hartley wrote:
I received an email from my fellow early 90's electric Skoda hatchback
driving friend Carlo, from Germany, this afternoon. It included the
following, of interest to some on the list:
i hope your ts li-ion batts will live long and prosper -my lead-gelled
cells now at nearly 63000km .slow, but stable.
It seems I under-estimated the distance he has added in the last
year. At about 30 km per charge average, that would be 2100
charge/discharge cycles! Amazing, especially considering this is only
an 84V car, with only 14 of the GC size 6V 160 Amp-Hr Varta
batteries. Consequently, each battery has to provide more current and
a higher percentage of the energy to move the car that 30 km than
would each of the higher Amp-Hr rated flooded GC batteries in a
typical 20 battery, 120V conversion, (driven the same way at the same
speeds). It shows also that Carlo is a skillful, conservative EV
driver. Note: these batteries are all still working well and there
have been no failures. Considering that he bought this set of surplus
batteries several years ago because it was the cheapest option for
him, I would say that he more than got his money's worth!
[snip]
Doug
--- End Message ---
--- Begin Message ---
>From what I know about real world issues between AGM and Gel batteries is:
AGM's have not lived up to my expectations. They are still better than wet
cells, in most cases, but have never performed to the specs listed. Gels are
limited in the current output, but they definitely live up to their specs.
As long as you limit the rate of current you take from them, i.e. capping it
at 200amps or below. They also require a charge rate between 13.8 and 14.1
max. Going over the charge rate will damage them quickly.
--- End Message ---
--- Begin Message ---
No typo, that is really 63,000 km. However, these batteries were not used,
they were new surplus stock, I think produced as replacement batteries for a
European EV.
Doug
----- Original Message -----
From: "Andrew Letton" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Monday, January 03, 2005 5:35 PM
Subject: Re: long life gels, re: About to purchase batteries
63000km from a set of used batteries? That's just about unbelievable;
could that be a typo? Could he have meant 6300km? Even 6300km would be
good for a set of used batteries.
cheers,
Andrew
Doug Hartley wrote:
I received an email from my fellow early 90's electric Skoda hatchback
driving friend Carlo, from Germany, this afternoon. It included the
following, of interest to some on the list:
i hope your ts li-ion batts will live long and prosper -my lead-gelled
cells now at nearly 63000km .slow, but stable.
It seems I under-estimated the distance he has added in the last year.
At about 30 km per charge average, that would be 2100 charge/discharge
cycles! Amazing, especially considering this is only an 84V car, with
only 14 of the GC size 6V 160 Amp-Hr Varta batteries. Consequently, each
battery has to provide more current and a higher percentage of the energy
to move the car that 30 km than would each of the higher Amp-Hr rated
flooded GC batteries in a typical 20 battery, 120V conversion, (driven
the same way at the same speeds). It shows also that Carlo is a
skillful, conservative EV driver. Note: these batteries are all still
working well and there have been no failures. Considering that he bought
this set of surplus batteries several years ago because it was the
cheapest option for him, I would say that he more than got his money's
worth!
[snip]
Doug
--- End Message ---
--- Begin Message ---
Some good ideas. I have a geared down cap start motor that is geared to
6rpm. It will make hundreds of cuts and might be powerful enough to drive
the cutter and the wire. I just need a tube to the cutter and a funnel
after to direct the wire to the cutter activator. Lawrence Rhodes.........
----- Original Message -----
From: "James Massey" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Monday, January 03, 2005 12:42 AM
Subject: Re: wire cutting machine (OT)
At 07:57 PM 2/01/05 -0800, Lawrence Rhodes wrote:
Can't comment on why but I need a lot of little wires. Using solid brass
22gauge. Not coated. No stripping. Simplist machine possible & yes I
found a 6rpm geared down cap start unit. I just need a cutter and someway
to actuate it. Lawrence Rhodes.......
Hi Lawrence (and all)
Being brass I guess it is hard and should cleave easily enough, I assume
round wire (not square or rectangular?) the issues that I would think you
need to look at are as follows:
Assuming that it comes on a spool, does it spring straight when it comes
off the spool? bonus if it does, since you can use the stuck-out length
against a mechanical stop to measure it (drive it out with a friction
drive until it hits a mechanical stop, then trigger the cutter). If it
doesnt spring straight, you may still be able to drive it against a stop,
but through a guideway to stop it from curving off, although you may need
to add an ejector.
Next assumption, that it is hard enough to cleave cleanly, you could have
a set of jaws made and hardened for a hand cropper - I don't know what the
American name is for this tool, but it is a bench-mounted hand-operated
rod and flat-bar shear for mild steel and similar bar up to 10mm or so
diameter (great if you need to make up a stack of buss-bars for an EV
battery pack). the rod is pushed through a hole that is in both jaws that
is a reasonably neat fit to its diameter, then the cropper handle is
pulled down, shearing the rod. It would be possible to solenoid or
compressed-air operate one of these tools, or try used machinery dealers
to see if they have a pneumatic one ready made. Drive the wire through
with a friction drive that will slip once the wire hits the stop, drive
the cutter on a cyclic timer, with the time set to slightly longer than
the feed time. The stop may need to be moving as well, to allow the
cropped part to be pushed clear.
It would be good to have the drive stop once the cutter is stroked down,
so there is no side-thrust on the cutter as it comes back up, restart the
drive once up (an electric clutch is good for this). A good source dor a
lot of drive parts, clutches etc is big old photocopiers.
Of course if you use pneumatic, you need an air compressor etc., which
adds other issues.
Rather than me keep waffling on with ideas, how do these concepts fit with
what you need to do?
James.
--- End Message ---
--- Begin Message ---
Hi all
Anyone had any experience of using "in line" planetary gears to gear down
ones motor then attaching to the prop shaft on a rear wheel drive?
Is this just another set of cogs to waste power or worth doing?
Still planning
Steve
--- End Message ---
--- Begin Message ---
I'm thinking along the same lines. I'm converting a
four wheel drive and I'm thinking of using the "shift
on the fly" reduction gears without the trans. or
possibly stacking two sets of redution gears as to
have a Low and High gear for street use and an extra
low for of highway use. I could tuck the motor where
the trans used to be and still have room up front for
an apu if need be. The "shift on the fly" type would
mean no need for a clutch, and all my shifting could
be controlled with switches.
Gadget
--- steve ollerton <[EMAIL PROTECTED]> wrote:
> Hi all
>
> Anyone had any experience of using "in line"
> planetary gears to gear down
> ones motor then attaching to the prop shaft on a
> rear wheel drive?
> Is this just another set of cogs to waste power or
> worth doing?
>
> Still planning
>
> Steve
>
>
=====
visit my website at www.reverendgadget.com
--- End Message ---
--- Begin Message ---
Here's an interesting device you might look into:
http://www.gearvendors.com/
--- End Message ---
--- Begin Message ---
Is this vehicle still around?
http://motortrend.com/roadtests/classic/112_0405_archive/
http://www.mclellansautomotive.com/sales-lit/bysub/electricvehicles/sundancer/index.shtml
--- End Message ---
--- Begin Message ---
At 3:09 PM -0600 1-3-05, Nick Viera wrote:
I finally made a battery bridge LED circuit for my Jeep (Thanks for the
schematic, Lee!). I actually have two bridges so each red LED covers 5
of my 20 batteries.
Hi Nick,
Good job! That looks great to me.
Have you tested it? It doesn't work well if the LED's are in
backwards. I just made one and got the red in backwards, it still
worked but the threshold was very high.
I would try disconnecting one of the end fuses. The Red LED should light.
Next put 3V of a small battery in series with one of the end
connections. Again a red LED should light.
Flip the polarity of the 3V battery and the other one should light.
If it does that, then it should work when you need it.
After more test drives, with my digital voltmeter on the battery side
and an analog meter on the motor side of the Raptor 600, I never see
anywhere near the pack voltage to the motor during WOT. I'm seeing
110-112 volts at the motor and 135-140 volts at the batteries during
WOT. This doesn't seem right to me...
At WOT the meter should work fine and there should be no switching going on.
Have you tried connecting both of them to one input to see if they
read the same? That might be a good test. Many of the EV analog
meters are highly inaccurate.
If it really is doing what the meters say, then it is not getting to
WOT even though it claims to be.
Also, If I set the Raptor's current limit pot lower (say to half),
should the behavior of the yellow WOT LED change at all? Also, I'm now
noticing that even with the pot turned all the way up (max current), I
can't pull more than 300 battery amps when I floor it in 1st gear
(whereas I used to be able to peg at 400 amps in 1st). I wonder if this
potentiometer could be bad?
I'm not very familiar with the Raptor. Do you know if the WOT light
just indicates full pedal position, or actually indicates a 100$ duty
cycle on the output?
--
-Otmar-
http://www.CafeElectric.com/ Home of the Zilla.
http://www.evcl.com/914 My electric 914
--- End Message ---
--- Begin Message ---
I looked at this unit, and it doesn't give much of a
reduction or overdrive. with the reduction gear from a
four wheel drive it would give you something more like
2nd and 4th gear... more in fitting with the torque
curves of an electric motors.
Gadget
--- Ryan Stotts <[EMAIL PROTECTED]> wrote:
> Here's an interesting device you might look into:
>
> http://www.gearvendors.com/
>
>
=====
visit my website at www.reverendgadget.com
--- End Message ---
--- Begin Message ---
Hi,
> That's the way it's supposed to work! If either red one lights, there's
> a problem.
I know... and I was afraid I'd be seeing red. I was happy to see that
the red LEDs never came on even when I was pulling 300+ amps. Maybe I
lucked out and didn't reverse/kill any cells in my pack as previously
thought...
> The motor side is not DC; it is a square wave switching between full
> pack voltage and zero. This is a difficult waveform for a meter to
> indicate accurately because there is such a powerful AC component.
That's why I used an analog meter on the motor side -- in hopes that it
would work okay. I tried my Digital meter on the motor side but it is a
bit jumpy.
Thanks
-Nick
1988 Jeep Cherokee 4x4 EV
http://Go.DriveEV.com/
--------------------------------------------
On Mon, 2005-01-03 at 17:24, Lee Hart wrote:
> Nick Viera wrote:
> > I finally made a battery bridge LED circuit for my Jeep (Thanks
> > for the schematic, Lee!)... I've yet to see any of the red LEDs
> > light... just the 2 green ones.
>
> That's the way it's supposed to work! If either red one lights, there's
> a problem.
>
> > I know Lee said red LEDs indicate there are reversed cells in the
> > pack. Could a red LED also indicate dead cells?
>
> A red LED lights where there is more than ~2v difference between the two
> half-packs. This can happen with a dead or reversed cell, or because you
> are drawing a heavy current and there are large differences in
> resistance (loose connections, a bad high-resistance cell), or during
> charging when the cells are out of balance (say, one 12v battery is at
> 15v when the rest are still at 13v).
>
> > After more test drives, with my digital voltmeter on the battery side
> > and an analog meter on the motor side of the Raptor 600, I never see
> > anywhere near the pack voltage to the motor during WOT. I'm seeing
> > 110-112 volts at the motor and 135-140 volts at the batteries during
> > WOT. This doesn't seem right to me...
>
> The motor side is not DC; it is a square wave switching between full
> pack voltage and zero. This is a difficult waveform for a meter to
> indicate accurately because there is such a powerful AC component.
>
> You may have to include an RC filter, or measure the voltage across the
> motor armature (which is considerably less noisy due to the inductance
> of the field).
--- End Message ---
--- Begin Message ---
50,000 km was about average for a daily driven maintained Force. If you
stop driving them, then typically they don't do as well. When I left,
James Worden had about 60,000km (that's over 35,000 miles) on his pack.
I would pass him on the highway (he was doing ~55 or 60 for just a few
exits) driving into work in the morning. He charged at work and did
between 35 and 40 miles a day, even in winter. I would see him drive a
gasoline car about 2- 3 times a year when he needed more range. 13 Deka
Gel batteries with heating and cooling, in a Force, in Boston.
Treat the batteries wrong and they will die in just a few thousand
miles. Correct charge profile, thermal management, and never
over-discharging can reward you with a long life.
Seth
On Jan 3, 2005, at 5:35 PM, Andrew Letton wrote:
63000km from a set of used batteries? That's just about unbelievable;
could that be a typo? Could he have meant 6300km? Even 6300km would be
good for a set of used batteries.
cheers,
Andrew
Doug Hartley wrote:
I received an email from my fellow early 90's electric Skoda
hatchback driving friend Carlo, from Germany, this afternoon. It
included the following, of interest to some on the list:
i hope your ts li-ion batts will live long and prosper -my
lead-gelled cells now at nearly 63000km .slow, but stable.
It seems I under-estimated the distance he has added in the last
year. At about 30 km per charge average, that would be 2100
charge/discharge cycles! Amazing, especially considering this is only
an 84V car, with only 14 of the GC size 6V 160 Amp-Hr Varta
batteries. Consequently, each battery has to provide more current
and a higher percentage of the energy to move the car that 30 km than
would each of the higher Amp-Hr rated flooded GC batteries in a
typical 20 battery, 120V conversion, (driven the same way at the same
speeds). It shows also that Carlo is a skillful, conservative EV
driver. Note: these batteries are all still working well and there
have been no failures. Considering that he bought this set of
surplus batteries several years ago because it was the cheapest
option for him, I would say that he more than got his money's worth!
[snip]
Doug
--- End Message ---
--- Begin Message ---
Hi,
> Good job! That looks great to me.
> Have you tested it? It doesn't work well if the LED's are in
> backwards.
Thanks. I did test it, and all of the LEDs work. I wired the most
positive and most negative sensing wires to the switched side of my
contactors, so when the ignition switch is off, the two center red LEDs
light (because the other three wires go straight to batteries). For now
I'm just removing the glass fuses on those 3 wires so I can turn it off.
> Have you tried connecting both of them to one input to see if they
> read the same? That might be a good test. Many of the EV analog
> meters are highly inaccurate.
Yes, but I'll do it again just to be sure.
> I'm not very familiar with the Raptor. Do you know if the WOT light
> just indicates full pedal position, or actually indicates a 100$ duty
> cycle on the output?
I think it means 100% duty cycle based on what the manual says:
"The Yellow LED illuminates when the throttle is wide open or "Floored".
This indicates that the controller is no longer switching and is
delivering maximum power to the motor. Should the LED not come on during
a full throttle condition, this indicates that the controller is in peak
current limit. Your trying to pull more amps through it than it can
deliver"
-Nick
1988 Jeep Cherokee 4x4 EV
http://Go.DriveEV.com/
-----------------------------------------
On Mon, 2005-01-03 at 18:25, Otmar wrote:
> At 3:09 PM -0600 1-3-05, Nick Viera wrote:
> >I finally made a battery bridge LED circuit for my Jeep (Thanks for the
> >schematic, Lee!). I actually have two bridges so each red LED covers 5
> >of my 20 batteries.
>
> Hi Nick,
> Good job! That looks great to me.
> Have you tested it? It doesn't work well if the LED's are in
> backwards. I just made one and got the red in backwards, it still
> worked but the threshold was very high.
>
> I would try disconnecting one of the end fuses. The Red LED should light.
> Next put 3V of a small battery in series with one of the end
> connections. Again a red LED should light.
> Flip the polarity of the 3V battery and the other one should light.
>
> If it does that, then it should work when you need it.
>
> >After more test drives, with my digital voltmeter on the battery side
> >and an analog meter on the motor side of the Raptor 600, I never see
> >anywhere near the pack voltage to the motor during WOT. I'm seeing
> >110-112 volts at the motor and 135-140 volts at the batteries during
> >WOT. This doesn't seem right to me...
>
> At WOT the meter should work fine and there should be no switching going on.
> Have you tried connecting both of them to one input to see if they
> read the same? That might be a good test. Many of the EV analog
> meters are highly inaccurate.
>
> If it really is doing what the meters say, then it is not getting to
> WOT even though it claims to be.
>
> >Also, If I set the Raptor's current limit pot lower (say to half),
> >should the behavior of the yellow WOT LED change at all? Also, I'm now
> >noticing that even with the pot turned all the way up (max current), I
> >can't pull more than 300 battery amps when I floor it in 1st gear
> >(whereas I used to be able to peg at 400 amps in 1st). I wonder if this
> >potentiometer could be bad?
>
> I'm not very familiar with the Raptor. Do you know if the WOT light
> just indicates full pedal position, or actually indicates a 100$ duty
> cycle on the output?
--- End Message ---
--- Begin Message ---
"How to convert to an electric car" 1980
Page 109:
"Eliot M. Estes, president of GM, has been widely quoted as
saying that electric cars will be available by 1985. Ford
has modified it's Pinto, Maverick, and other compacts,
including the Fiesta."
http://www.amazon.com/exec/obidos/tg/detail/-/051753990X/ref=lpr_g_1/102-2904835-9273769?v=glance&s=books&n=283155
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>Whether it will "cut it" depends on the controller.
>
>In my case very peppy EV does not draw more then 100A
>for 99% of the time. In fact, inverter is limited
>to 280A but this is 100kW of power. More than enough
>for
>any normal EV.
Yes, but what is the required pack voltage for your
motor/inverter combination? 288+V of SAFT STM100 NiCds is
quite a bit of weight, more batteries than I could
realistically fit into a car with a GVWR of about 2,200
pounds, of which I wouldn't want weighing more than 2,600.
We're talking 1,400 pounds of batteries(At 29 pounds each)
for a max of about 95 battery horsepower, assuming 250
battery amp limit and not accounting for voltage sag. This
would work great in a Red Beastie knockoff, but not in a
tiny sportscar that cannot realistically have more than
1,000 pounds in batteries. On Rudman's site, the SAFT STM100
batteries assembled into packs of two batteries at 12V
nominal can go up to 1000 amps and the assembled module
sagged to 6V, but I remember reading on this list that high
current draws will drastically shorten life(STM100s
shouldn't be dishing out more than 250 battery amps was the
general concensus). With the right controller, that would
provide the 100 kW, but with either reduced cycle life on a
realistically-sized pack, or provide that power and high
cycle life on a pack too large for the type of car I'm
looking to convert.
>As of many 6V cells to water, SAFT uses automatic
>watering
>system with water running from one cell to another
>following
>electrical connection. I use 3.6V LiIon cells, about
>twice
>as many as 6V NiCds I'd need for the same voltage.
>Of course no need to water them, but in terms of
>interconnecting,
>iti s not that bad, and - one time deal. I've done
>160 caps
>in series - not too bad either.
I do believe I was referring to the BB600 NiCds on the
watering system, and not the SAFT STM100s though. Do the
BB600s have an automatic watering system? That would be
quite a hassel if they did not. I'm interested in how those
SAFT STM100 batteries can be positioned. I have doubts that
they can be placed like a sealed AGM could, even with their
watering system.
As to those Li Ions and Ultracaps you have, that's a bit out
of price range for this particular project. Maybe it might
work for a university-funded project where there'd be about
$50k to work with, or perhaps if I saved up a bunch of money
over the period of a few years. But I could not justify
spending that kind of cash unless it had high
horsepower(150+ assuming sub 2,400 pounds weight) to go with
it...
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Philippe Borges wrote:
Yes but like Victor finally accepted to say about TS cells ;^)
it works in THIS particular application.
That actually applies to any battery - it must match the
intended application to get decent results.
We need standard repeatable torture test so:
for exemple: take 4 cells together to make something similar "12V" battery
and discharge 1C then charge C/3 and then record, count, mesure...
It is being done. In general; the problem for individual
testers is willing to buy expensive battery just to murder it.
Anyone can test it if you hand them for free $5000 worth of batteries.
With 1H pause, its 4 to 5 cycle per day, 2 month would be sufficient to have
usable data and tell if yes or not TS cells are good batteries to support or
something still too expansive for kWh it gives.
Define "good" batteries". That depends on your application
and appetite.
Define "Expensive". That depends on how much money one is
able and willing to commit to your hobby.
imho an EV battery MUST be happy at 1C discharge rate because its the usual
EV discharge rate (100ah battery)
It is wrong assumption. PbA Hawkers are "happy" at 10C,
this doesn't mean you can use 10Ah Hawkers in your EV.
On other hand 100Ah Hawkers (if exist) would be ovewrkill
for the most as you'd never be able to take advantage of
the max current they can deliver (drag race aside).
Otherwise you are trying to juice an electric Humwee with AA cells, needs a
lot of them in serie and/or parallel to keep voltage high and current
low...though well done it will work for sure, the gain/cost ?
See above. Do not choose TS (or any other for that matter)
batteries if they do not match your vehicle and then conclude they are
bad. 200Ah cells are practical cells for long range "no worries"
EV. 100Ah ones are absolute minimum for careful drivers and techies.
My 90Ah pack is undersized, but it is supplemented by ultracaps.
Still if I would do it again, I would not choose 90Ah cells.
We have this data for all EV batteries we use, i'm disappointed than after 1
year more world availability, still no such cycling data on TS cells is
coming :^(
What have *you* done to make such data available then? Sitting and
complaining while waiting for others to do something for you is
of course the easiest. You are disappointed that I (or anyone else)
did not provide you the data you want? Buy one cell and do the test,
Sheer wanted to test NiZn, so he bought it. No time to do it,
Joe helped out.
Lee wanted to test TS LiIons, so he bought few to answer his
own questions.
As far as I know, none of them are too rich or wasteful.
Why can't you do the same?
We have an rEVolution coming in France, two company have announced lithium
EV for 2006, will see if this happen.
Yes, will see. Simply wait until 2006 and write the post about it then.
Just question of time...
Philippe
How old are you Philippe, may I ask?
--
Victor
'91 ACRX - something different
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Jeff Shanab wrote:
I live in Fresno california, the radio stations around here count the
number of days over 100 in the summer(and the number of days till we
go without sunin the winter, fog central,in te winter)
AirC is a must. One of the things I plan is to have the Air started by
the remote control for the alarm, before I get to the vehicle, my
friends and coworkers will just "die" with envy.
No fair stealing my ideas! ;-) Here in Orlando, FL, I was planning on
running the Air off a timer, while the charger was still plugged in.
All my friends will leave work to sweltering cars and untouchable
steering wheels; I'll have a nice cool cabin. I've picked up a
treadmill motor from sciplus.com to turn the compressor. Unfortunately,
I haven't upgraded to 134a; I intend to use the original '88 Honda hardware.
Judebert
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David Roden wrote:
On 30 Dec 2004 at 18:52, Dragan Stancevic wrote:
I asked them and TS about pricing information and, TS came much much cheaper
than they did.
That should come as no surprise. It appears to me that the Valence product
is a more or less complete system that directly replaces lead acid batteries
and apparently requires no changes to your charging system (remarkable for
lithium based batteries). OTOH, Thundersky offers raw modules, no BMS. Of
course TS are going to be cheaper!
Thundersky also manufacture their modules in the Chinese sweatshops where
the labor typically costs 20 to 50 cents an hour (though for all I know
maybe Valence do too).
David, I'm glad I found this to be not the case. The factory
actually is moving to different location, so I didn't get
chance see actual workers in action. In general they indeed pay
very minimum for the labor, but this applies to any labor
in China in any field.
Once I'm there again, I'll confirm this thing about labor
and working conditions at TS.
You have to ask yourself, how much is your time worth, and how many TS
modules are you willing to risk damaging while you tinker with your own BMS?
Folks with lots of EE background, and who have more time than money, will
no doubt want to "roll their own." Others who just want to drive a reliable
EV might decide that the drop-in solution is a better one for them, even at
a much higher cost.
100% agreed!
All this is cojecture since I have no experience with either battery, but in
general I welcome any EV product that eliminates something I can screw up.
<grin>
Isn't it fun screwing up things? :-)
Ask Wayland - he "blows things up so you don't have to"...
BTW, John *loves* TS LiIons:
http://www.metricmind.com/misc/li-ion_plasma-1a.jpg
Victor
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Rich Rudman [mailto:[EMAIL PROTECTED] wrote:
> Yes... but what is the effect of the 3 amps of bypass current
> Roger????
> Think outside the single battery relm....
Well, I'm starting to wonder if I'm just particularly dense these days,
but I still don't get it. The big picture effect of 3A of bypass
current is that the series string gets to charge at 3A higher current
than it would without regulators. Period. We'll deal with the little
details below.
> So... what you get is a very stiff AGM... little amps
> results in LOTS of voltage. Enough to over pressure the
> battery, you get venting. BAD!. So...you have to add some
> flexability to let the pack sluff off the amps that the weak,
> not full yet batteries still need. else your voltage goes up,
> the charger cuts back, the timers are set, and time out
> before the low ones come up to par. All the while the really
> full ones are taking a hit in the recombiners... and IF they
> keep up All is OK. In my practice, most don't.
What you are describing is what happens with a reasonably dumb charger
(no offense to the PFC series, but they are a bit short on brains at the
moment ;^) and no regulators *or* voltage sensors.
A more intelligent charger is not going to just time out after a fixed
duration, but will do something more elegant like continue until the
current stops tapering, or tapers to a fixed value, or some timeout
occurs, etc. so that the string is fully charged.
More to the point, what I was asking you is to explain what benefit
other than tapering at 3A greater current does equipping the pack with
full-featured regs provide vs equipping it with simpler, cheaper voltage
sensors since either one provides exactly the same feedback capability
to the charger? That is, if I put a reasonably simple voltage monitor
on each battery such that if any of the batteries exceeds the voltage
setpoint the charger is told to yank back the output current, then how
does the ability to bypass 3A around any module buy me anything other
than the ability to charge at 3A higher current?
> What you are being directed to engineer is a recipe to
> solve this effect with only voltage and time. It will work.
> But you have no control over how hard you push any single
> battery. The perfect system would find the fullest and
> highest voltage battery....monitor it's pressure... Do
> something to relieve it....then repeat until the WHOLE pack
> is at this point.
I think there are two different systems and challenges here:
- a charger that cannot 'see' the individual battery voltages; this
system has to tradeoff charge time and may have to watch the pack
voltage/current (and rates of change of pack votlage/current, etc.) in
order to fully charge an imperfectly balanced pack without venting (or
venting excessively). This is the challenge facing me.
- a charger that can 'see' the individual battery voltages; this system
can charge as hard as the highest voltage battery will allow since it
can regulate the charge current to keep the highest voltage module
wherever it wants. If the voltage sensing means includes bypass
capability then the charger can regulate the charge current that much
higher while still keeping the module voltage from exceeding the
setpoint and the regulator from melting down.
> So... the 3 amps is the added Give you need
> to let the stiff ones live.
I still don't understand what this 'give' is that you believe the regs
provide, nor why it should be required once you have the regs tied into
the charger such that it is going to yank back the charge current when
the regs start screaming. I do appreciate you trying to explain it to
me, and hope you don't give up quite yet ;^>
Is it perhaps a function of how your PFC charger control loop
behaves/interacts with the regs that causes you to believe that you need
this 'slop' in the system for it to work well?
> In fast charging... the ability
> to move the overecharge energy out of the way, is the limit
> of how fast you can get then all filled right.
No argument here. I just question how much effect on charge time that
extra 3A provided by the regulators really has. When your charger
outputs just 10A, 3A is a lot, but when you start talking about 80-200A
of fast charge, +/-3A gets to be a small difference and is only applied
through part of the charge cycle. Remember, what I was questioning is
what the real benefit of using full-featured regs vs simple voltage
sensors to yank back the charger output is, not regs/sensors vs nothing.
> Having a reg blast the top off a voltage spiking AGM...
> does just that, but the pulse doesn't just dissapear, to gets
> dumped onto the next reg, Minus the energy just got turned to
> heat. The next battery sees the main charge amps plus the
> pluse that just got dumped on it.
I'm not sure I understand this. The current in the series string is the
same at all points. If the act of a reg switching on/off were to cause
a current pulse, then that pulse is experienced by every battery in the
string, including the one whose reg just switched.
If the reg switches a FET+load across the battery to divert (up to) 3A
of charge current, then the current through the battery drops by (up to)
3A, but the total current continuing through the string remains the same
since the current bypassed by the reg is added back to that passing
through the battery before it continues to the next module in the
string. Other than a bit of transient noise at the on/off transitions,
I don't really understand how/why there should be any current pulse...
at least not due to the reg specifically.
I suppose that if the charger is in constant voltage mode and a reg
fires to reduce one module's voltage slightly, then the battery pack
voltage appears to have decreased slightly and so the charger's output
current may increase briefly. However, even for this to happen depends
on the regs being relatively slow to respond to an over-voltage
condition, or for them to require a fair amount of overshoot before
firing. That is, if the reg begins bypassing as soon as the module
reaches 14.8V, then the total pack voltage remains unchanged from the
charger's perspective, and so it will not provide any current pulse.
If, however, it fires only after the module hits 15.0V, then the pack
voltage will drop by 0.2V and the charger's output current may increase
(causing the reg to have to bypass even more current, unless it is
already at its max, in which case the module voltage will spike up
despite the reg).
> So if it is a low Battery, it sees a current pulse, and
> it's voltage jumps. If this is a low one, it just eats
> it, and adds to that batteries stored power.
And, if the battery is one whose reg is already bypassing all it can,
then it still sees the current pulse and its voltage jumps over the
desired limit.
> I have seen a very stiff pack do the "chasing
> Christmas tree light effect". One pulse starts a cascade of
> Reg pulses. If it goes from one end of the string to the
> other, I would say that pack is done rather well.
I don't doubt what you have seen, I just question if you are seeing it
for the reasons you think. I have seen a similar effect when doing the
manual regulator dance on YTs, but what I observed is that as soon as
you bypass current around the highest voltage module, one of the others
that was previously fine spikes up; bypass it, and another 'good' one
spikes up. It seems to me that when you apply a constant voltage to a
series string the voltage divides across the modules at least in part
based on the internal resistance of each module. When you bypass a
module the total voltage remains the same, but now there is a little
more of it to be divided amongst the remaining unbypassed modules, and
one of them typically pops up a little higher than the others. If the
string is well-balanced, then all of the modules are going to be near
the 14.8V level of the one whose reg fired, so the one that pops up
higher will likely fire its reg. And so on.
> > this is at least the 3rd plausible theory I've heard.
>
> And the other two are???
Off the top of my head:
- at least some of the Zivans would cycle back on automatically if the
pack voltage dropped below some threshold, and I've heard that this has
been identified as at least one cause of killed packs
- the Zivan algorithm that applied a fixed duration finish charge
regardless of DOD.
> I don't understand why they say this.
> It clearly results in damage to do this. by not permiting
> this, you seam to get long life and no venting. Everybody
> with a Pedigree say more voltage and longer hold times. All
> us folks with lab time and busted knuckles... say less volts
> and protection. And have Nice long lived packs. Who's
> right??? I dunno. But I seam to have pretty good results.
It is certainly hard to argue with real world data, but at the same
time, I haven't seen particularly convincing real world data either way
yet. Sure, a very few EVers have gotten extremely good cycle life from
their YTs, but we don't have any good data on what the actual DOD was,
nor on the effect of discharge rate, nor on the recharge algorithms,
etc. on the cycle life. In most cases, we don't even know what the Ah
capacity of the pack is to start with or at end of life.
The guys with a "pedigree" tend to have the test data to back up their
opinions. The data may or may not indicate that the preferred algorithm
is suitable for how you or I use our batteries, and often there are
practical difficulties adapting the preferred algorithm from 1 battery
to a string of 10-20+, but the data will show what performance is
expectable with the preferred algorithm under the identified test
conditions.
> Until these guys have 2x the delivered Kwhr and 2x the
> published cycle life tests, I really don't want to listen
> very hard to them. They designed these class of batteries,
> Why are they not seeing the same thing as I do????
On the other hand, they designed this class of batteries; why would you
*not* listen to them?! I think the biggest reason they aren't seeing
what you do is that the test methodology is different; for instance,
what DOD are you testing to? The YT tests I've seen show rapid cycling
to 100%DOD, and clearly show that the Optima recommended algorithm
yields better performance/life than the tested alternatives. I've also
found that battery companies are the first to admit that there are any
number of ways to properly charge a battery, and that while they may
have some details that they are quite sticky about (initial charge rate,
or absorption voltage, etc.), they will generally admit that their
recommended algorithm is not the only way to properly recharge their
product.
> > > As Ryan is finding out ...maybe we should drop the end
> > > voltage for Orbitals down to 14.6, instead of the Optima
> > > Yellow Top tried and true 14.8 volts. Orbs do seam to
> > > vent at a lower voltage.
> >
> > This is venting at the bulk/absorption transition that
> > you're seeing?
>
> Yea... I saw it at 14.5 once... just after a 80 amp bulk
> event. The Orb was in fine voltage condition, but it was
> clicking. Now that I have a couple read 5 to 10 cycles on the
> pack this has stopped entirely. I say some new Yts do this
> once....In the first 10 cycles, a little venting is
> forgiven... at 50 to 100 amp rates, but it sure should
> terminate that rate!.
I've seen this also and suspect it may be due to cell imbalances that
result from differing self-discharge rates. With the YTs, there are
just 2 vents for the entire battery while I understand the Orbs have a
vent per cell; this may make the Orbs more likely to vent since there is
less headspace available to a gassing cell before a vent must open.
Cheers,
Roger.
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