EV Digest 4001
Topics covered in this issue include:
1) Re: Why don't NiCd manufacturers make an AGM?
by Ralph Merwin <[EMAIL PROTECTED]>
2) Re: Motors in series? Torque vs. power?
by "Rich Rudman" <[EMAIL PROTECTED]>
3) Re: wire cutting machine
by Martin Klingensmith <[EMAIL PROTECTED]>
4) DC to DC question
by TiM M <[EMAIL PROTECTED]>
5) Re: High current li-ions from Sony
by "S. David Lalonde" <[EMAIL PROTECTED]>
6) Re: Jeep EV (Battery LED, Raptor controller questions)
by Otmar <[EMAIL PROTECTED]>
7) Re: Simple First Conversion Query
by Lee Hart <[EMAIL PROTECTED]>
8) Re: Air conditioning - dumb questions
by Lee Hart <[EMAIL PROTECTED]>
9) Re: Sealing a Curtis controller
by Lee Hart <[EMAIL PROTECTED]>
10) Re: Refining Hybrid truck ideas
by Lee Hart <[EMAIL PROTECTED]>
11) Re: Motors in series? Torque vs. power?
by Lee Hart <[EMAIL PROTECTED]>
12) New clutch for my truck works much better
by Paul Wallace <[EMAIL PROTECTED]>
13) RE: Simple First Conversion Query
by "Adams, Lynn" <[EMAIL PROTECTED]>
14) Electric truck wanted in Nevada
by [EMAIL PROTECTED]
15) Re: Motors in series? Torque vs. power?
by "David Chapman" <[EMAIL PROTECTED]>
16) Re: TS Cell Balancing via Shared Transformers
by Lee Hart <[EMAIL PROTECTED]>
17) Re: Jeep EV (Battery LED, Raptor controller questions)
by Lee Hart <[EMAIL PROTECTED]>
18) Re: Air conditioning - dumb questions
by "David Roden (Akron OH USA)" <[EMAIL PROTECTED]>
19) Re: DC to DC question
by Lee Hart <[EMAIL PROTECTED]>
20) Re: Follow-up on Valence Li-Ion batteries in 12V size
by "Philippe Borges" <[EMAIL PROTECTED]>
21) Re: Planatery gear set
by "garry" <[EMAIL PROTECTED]>
22) Re: Thunder Sky, Re: Follow-up ...
by Victor Tikhonov <[EMAIL PROTECTED]>
23) Re: Thunder Sky, Re: Follow-up ...
by "Doug Hartley" <[EMAIL PROTECTED]>
24) Re: Follow-up on Valence Li-Ion batteries in 12V size
by "David Roden (Akron OH USA)" <[EMAIL PROTECTED]>
--- Begin Message ---
Correct. For my vehicle, this worked out to about every three months.
I wanted to give an example instead of a spec, but forgot to point that
out.
Ralph
Philippe Borges writes:
>
> In fact, they need to be watered every 1000Ah over-charged (Ah in
> equalization phase)
>
> 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: "Ralph Merwin" <[EMAIL PROTECTED]>
> To: <ev@listproc.sjsu.edu>
> Sent: Tuesday, January 04, 2005 2:39 PM
> Subject: Re: Why don't NiCd manufacturers make an AGM?
>
>
> > Jude Anthony writes:
> > >
> > > I'm listening to the benefits of NiCd batteries, but I really don't feel
> > > like using flooded batteries. Even with a watering system, it still
> > > just seems like a pain.
> >
> > The SAFT STM5-100s need to be watered about every three months, and it
> > takes about 20 minutes. If the system is setup correctly, you just put
> > water into one end of the watering circuit and keep filling until water
> > runs out the other end. Repeat for each circuit in the pack (up to 10
> > modules per circuit).
> >
> > Ralph
> >
>
--- End Message ---
--- Begin Message ---
This is not the series parallel that We Racers use... but yes it would work.
I certainly would not recommend this for any but the hardcore racer and
motor hacker.
This works but it upsets a lot of the timing locations, and would make
normal use hard to achieve.
So if you need it simplified...it's not for you.
----- Original Message -----
From: "Aaron NMLUG-EV" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Tuesday, January 04, 2005 7:22 AM
Subject: Re: Motors in series? Torque vs. power?
> On Tue, 2004-12-28 at 13:08, Rich Rudman wrote:
> > Lets keep in mind that the AVDC motors 6.7,8 and 9 inchers have a series
> > paralel setup as stock. Each north and south pair are in paralel with
each
> > other.
> > So.. Stock is 1/2 field weakened already.
> > So... look again closely into your AvDC and tell me what you
see.....
> > from each stud to the next, is only two coil sets, one CW and the other
CCW.
> > So.. Da Juice flows both ways.
>
> Can we simplify this for people who are not very familiar with
> Advanced DC, or even motors in general...
>
> Does this mean that with a contactor or two, I could wire
> a single 9" ADC for series/parallel switching with a Zilla?
>
> aaron
>
--- End Message ---
--- Begin Message ---
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.......
Lawrence,
If you need a fixed wire length you could have a set wheel size that
trips a switch each revolution, firing a solenoid with an attached
cutter - 22ga is pretty easy to cut.
--
Martin K
--- End Message ---
--- Begin Message ---
I’m looking into adding a DC to DC converter to the
truck. I’ve found a reasonably priced 29 amp unit from
Astrodyne, model SD350D-12 for $129 plus shipping.
Specs are here:
http://www.astrodyne.com/pdf/SD350.pdf It’s the D
model on the second page.
The original generator in the truck was only 30 Amps
so I think this unit should be big enough. Is it as
simple as connecting the output through a 30 amp fuse
to the 12V battery and setting it to 13.8V? The input
will connect to the pack after the main contactor so
the DC to DC is out of the circuit when the PFC-20 is
doing its thing. The unit is rated at 350 watts and
claims 83% efficiency, using these numbers I should be
able to get away with a 5 amp fuse on the input. (96V
pack, soon to be upgraded to 120V) I want to make sure
I’m going about this the right way and will be keeping
all the smoke where it belongs.
Thanks,
Tim McCann
Electric '61 Corvair Rampside
__________________________________
Do you Yahoo!?
Yahoo! Mail - now with 250MB free storage. Learn more.
http://info.mail.yahoo.com/mail_250
--- End Message ---
--- Begin Message ---
I cycle tested Moli Energy (Molicel) Li-ion laptop cells (ICR 18650 circa
2000 to 2002) with Lithium Colbaltite cathode materials. They were tested at
both 4.2 and 4.3 V upper cut-off voltage. Using 4.3 V results in
significantly shortened cycle life (~1/3). Reducing the upper cut-off
voltage to 4.1 V did not significantly improve cycle life. Hence they
stayed at 4.2 V. 4.5 V? Maybe if the cathode material is significantly
different. Moli Energy also makes cells using spinel cathode (Manganese)
but they still use the same upper voltage cut-off, 4.2 V. The circuitry
used in the laptop battery packs can allow for excursions up to 4.25 V per
cell given measurement errors in the components.
Instead of 4.5 V try keeping to only 4.2 V and see what kind of cycle life
you will get. I'd guess a whole lot more for little sacrifice in capacity
per cycle.
I believe the 4.1 V versus 4.2 V was originally because of the anode
material (level of graphitic carbon), not the cathode, though of course both
play a role in the final cell voltage.
Sincerely,
David
S. David Lalonde / [EMAIL PROTECTED]
Liion Power Products Inc. / http://www.liionpower.com
Li-ion & NiMH batteries for electric cycles & more!
http://groups.yahoo.com/group/liion_power_products/
http://liionpower.blogspot.com
Ph: 604 880 1928
----- Original Message -----
From: "Victor Tikhonov" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Monday, January 03, 2005 7:27 PM
Subject: Re: High current li-ions from Sony
Philippe and all,
The max allowed voltage on charge is different for manganeze
and cobalt versions. So they co-exist if you use common
denominator, but you'd underutilize cobalt ones which
allow up to 4.5V per cell.
Victor
--- 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.
Ah, but they will still do that if the red LEDs are in backwards.
I found that the threshold for them to turn on was 4V instead of 2V
when they were in backwards.
You might want to try just moving one end by 3V to insure it is as
sensitive as you want.
This is not to say that I expect your battery to have problems, only
that it's good to fully test anything that you build and rely on.
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"
Yes that sounds right.
I wonder why you are getting different readings at full throttle?
You might check the voltage drop at the controller by putting the
analog meter from the B+ terminal to the M- terminal and checking
while the LED is on.
That will tell you how much voltage the controller is dropping. It
should be under 3 volts at full on.
--
-Otmar-
http://www.CafeElectric.com/ Home of the Zilla.
http://www.evcl.com/914 My electric 914
--- End Message ---
--- Begin Message ---
[EMAIL PROTECTED] wrote:
> I'd like to do a first conversion the simplest possible way and
> wonder what that would be. I've read through "Convert It" and
> have been doing a lot of site surfing.
The simplest way is to buy a pre-built conversion. All the hard work is
already done for you. You can save a lot of money by buying one that
needs work, and do it yourself. Often it will come with bad batteries,
or some less-than-optimal parts; thus the price had better be low!
If you want to convert something yourself, it is easiest if you pick a
vehicle that many people have done before. This way, there are lots of
working examples to copy, and you can find "stock" adapter plates,
battery boxes, etc.
The old Beetles make "ok" EV conversions, but are pretty dated nowdays.
It will be hard to find a good donor car. The layout isn't particularly
good for battery placement, wind resistance and handling are poor, so
you don't get a particularly good-performing EV.
--
"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 ---
[EMAIL PROTECTED] wrote [on using a home A/C in an EV]:
> 1) I presume I will need a HO alternator.
It depends. New home A/C units have to meet efficiency standards. Small
window units can be surprisingly frugal. It's possible to find ones that
only draw about 6a at 120vac (720w). With a 90% efficient inverter,
that's about 60 amps at 13v. Most cars have 60-100a alternators, so you
might be able to squeak by. The system would be running off the battery
at low speeds, and catch up at high speeds and when the A/C cycled off.
I'd try it with the stock alternator. If it can't keep the battery
charged, get a higher output alternator.
> 2) I presume I will need an inverter. The question is, can or
> should I hook the inverter up to the accessory battery? Or
> will I need another battery or batteries, connected to the HO
> alternator?
You don't need a second battery unless you anticipate long periods using
the A/C without the engine running. I would just replace the stock
"starting" battery with the largest deep-cycle battery that fits.
Connect the inverter with the shortest, heaviest wire you can manage, to
minimize voltage drops.
In your case, you have an ICE. In an EV, you have a high-voltage battery
pack. In this case, it is more efficient to run the inverter (or motor
controller) from the pack voltage.
> I'm now thinking that, counterintuitive to my thinking at least,
> all the current coming out of the battery and going into the
> inverter would in actuality count as "amp draw" from the battery
> itself...
To a first approximation, the inverter, battery, and alternator are all
basically in parallel; so it doesn't matter exactly how you connect
them. The battery just charges/discharges at a current defined by the
actual voltage across its terminals (and its state of charge). When the
engine is running, the alternator is trying to make it about 14v. A
fully charged battery will draw a low current (about 1 amp) at this
voltage.
The sum of the currents is always zero; AlternatorAmps + BatteryAmps +
InverterAmps = 0. So if the alternator produces +60a and the battery
draws -1a, then the inverter has -59a.
But as a practical matter, the wiring in most cars is undersized (the
smallest they could get away with), and there are significant voltage
drops between the battery and alternator. They often "design in" this
voltage drop, so the alternator might produce 14.2v to get 13.8v at the
battery. So, I would probably replace the wire from alternator to
battery with a much heavier wire. Failing this, I would connect the
inverter directly to the alternator, to give it as much voltage as
possible.
> 3) And what do you think of my plan to mount this thing in the
> trunk, with the "cool air side" sticking into the car through
> the back seat?
This will work, as long as you leave the trunk open or otherwise provide
considerable venting and airflow back there.
--
"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 ---
Dave Cover wrote:
> I have a Curtis 1221B-7401 and I need some advice. The end opposite
> the electrical connections has popped off and I need to seal it back
> up. It's a snug enough fit that I can't put it back in place.
It happens. Mine is loose, too. It looks like they just press it into
place, and expect it to stay there. There is a black potting compound
that is supposed to glue it in place. With temperature cycles,
atmospheric pressure changes, etc. it works loose.
The Curtis case only looks sealed; it isn't. Depending on your climate
and mounting location, some collect water inside from
temperature/pressure/humidity cycling. This water causes all sorts of
trouble!
> I looked in the archives... One recommendation included provision
> for thermal expansion (a balloon), preventing pressure buildup.
Right. You can try to seal a rigid case with air inside "airtight". But
unless it is a perfect hermetic seal (expensive!) it will always leak.
It will "breathe" in/out thru tiny pinhole leaks and cracks as the
temperature and air pressure change.
So one solution is to put a balloon inside. The balloon is vented to the
outside. As air pressure increases, it inflates the balloon inside the
case; as it drops, the balloon deflates. In both cases, there is no
pressure difference between inside/outside, so the tiny cracks and leaks
won't suck air in/out, and the interior stays dry.
Another solution is to fill the case with something other than air;
potting compound, oil, etc.
> Anyway, what should I use to glue it back together? Hi temp RTV
> sealant?
RTV works, but is hard to remove.
What I wish Curtis did is to use a flat plastic end covers, with a
greased/RTV'ed gasket for sealing, and screws to hold it in place.
Then, provide a tiny drain hole somewhere. It would have to be small
enough to keep bugs out, and oriented on the bottom (so it lets water
out, not in!)
--
"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 ---
Jeff Shanab wrote:
> With todays newer fuel injected car can we plug a datalogger into
> the diagnostic port to capture fuel injector and rpm data? Would
> that provide us with a good fuel usage numbers. What about using
In theory it should. But, I've seen precious few products that actually
make fuel consumption data available. If it were easy, I would expect to
see "miles per gallon computers" on the market that do it.
--
"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 ---
Aaron NMLUG-EV wrote:
>
> On Tue, 2004-12-28 at 13:08, Rich Rudman wrote:
> > Lets keep in mind that the AVDC motors 6.7,8 and 9 inchers have a series
> > paralel setup as stock. Each north and south pair are in paralel with each
> > other.
> > So.. Stock is 1/2 field weakened already.
> > So... look again closely into your AvDC and tell me what you see.....
> > from each stud to the next, is only two coil sets, one CW and the other CCW.
> > So.. Da Juice flows both ways.
>
> Can we simplify this for people who are not very familiar with
> Advanced DC, or even motors in general...
>
> Does this mean that with a contactor or two, I could wire
> a single 9" ADC for series/parallel switching with a Zilla?
Yes, after a fashion. You would only be series/parallelling the fields;
there's still only one armature, so the same basic max current limits
apply. With two motors, you can run double the current in parallel.
As compared to the stock arrangement (4 fields, two parallel strings of
two in series):
- With all 4 fields rewired in series, you get more torque per amp,
but less rpm per volt. Max motor current rating is reduced.
- With all 4 fields rewired in parallel, you get less torque per amp,
but more rpm per volt. Max motor current rating is unchanged.
We don't normally switch series fields in series/parallel because their
resistance is so low that the switches used have as much (or more)
resistance. So, variations in the switch resistance cause the current in
the different field coils to divide unequally. This causes efficiency
and arcing problems.
--
"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 ---
I've been driving my S-10 with a clutch for about 5 years, after 3 years
without. I bought the clutch and pressure plate from Clutchnet. It has
been shuddering for about a year and a half and was making some other
unpleasant noises, making me think that I might have worn the driven
disk down to metal.
Over my Christmas vacation, I bought enough jacks and stands to get at
the motor and transmission from underneath the truck so that I could
disassemble and inspect the clutch. This required jack stands under the
front, an SUV high lift 2 ton jack under the motor, and a 2.25 ton jack
with a transmission cradle. I don't have any air tools so getting the
cross member bolts out was a real battle.
Once apart, I found that the pads of the driven disk were very worn, but
not down to metal yet. The flywheel and pressure plate were very
smooth. I then called Clutchnet to order a new driven disk. My how
technology improves over the years. After a discussion of the
application, the fellow at Clutchnet recommended the kevlar-kevlar disk.
The disk takes a real beating on upshifts as it must absorb all the
energy of bringing the motor/flywheel assembly down about 1000rpm for
every gear. He says that this disk is much tougher than the fiber-fiber
disk I had been using. I also noticed that the spring pack in the
center of the disk is much beefier than the old one.
While I had things apart, I changed the transmission mount to a poly
plastic version. I also added a left hand torque strap from the
transmission to the A arm mount on the drivers side. I already have one
of these straps on the passenger side. The are crude, 3/32 x 1.5" strap
steel.
The end result is no more shuddering and very smooth shifting up and
down. The downside so far is the amount of transmission noise
transmitted to the frame by the straps. If I push in the clutch and
spin the motor/flywheel only, the balance is good and there isn't much
noise. If I let the clutch out, even in neutral, the full glory of the
T5 transmission comes ringing through. The noise is even worse when the
gears are engaged and the transmission is delivering torque to the
wheels. You can hear the gear teeth cogging, espcially in first gear.
I am using Royal Purple Max ATF. I will attempt to take care of this
noise problem over the summer. I plan to make a torque rod to attach
from the transmission to under the driver side frame rail, using the
stock style rubber transmission mount screwed to the frame rail.
Paul Wallace
'91 Chevy S-10 full of SAFT Nicads
--- End Message ---
--- Begin Message ---
I agree completely with Lee.
I purchased a previous conversion, in good shape with good batteries,
and since buying it I have:
Replaced motor brushes (sand in motor-prevent reoccurrence with screen
for sand guard)
Pulled and replaced the charger (twice: once under warranty, once again
after 30,000 miles)
Replaced the controller (after a bone-head move)
Replaced the battery pack twice, requiring making new cables.
Replaced several battery heaters and upgraded the heater control system
Replaced the emeter (failed as a result of the controller bonehead move)
I think I have touched everything on the electric side except the
motor-transmission interface and the vacuum braking system. Learned a
lot, been on the road a lot. Now feel ready to do a new conversion with
some experience.
Buy a used one and play with it for a while!
Lynn
See my 100% electric car at http://www.austinev.org/evalbum/379.html
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Lee Hart
Sent: Tuesday, January 04, 2005 12:32 PM
To: ev@listproc.sjsu.edu
Subject: Re: Simple First Conversion Query
[EMAIL PROTECTED] wrote:
> I'd like to do a first conversion the simplest possible way and wonder
> what that would be. I've read through "Convert It" and have been doing
> a lot of site surfing.
The simplest way is to buy a pre-built conversion. All the hard work is
already done for you. You can save a lot of money by buying one that
needs work, and do it yourself. Often it will come with bad batteries,
or some less-than-optimal parts; thus the price had better be low!
If you want to convert something yourself, it is easiest if you pick a
vehicle that many people have done before. This way, there are lots of
working examples to copy, and you can find "stock" adapter plates,
battery boxes, etc.
The old Beetles make "ok" EV conversions, but are pretty dated nowdays.
It will be hard to find a good donor car. The layout isn't particularly
good for battery placement, wind resistance and handling are poor, so
you don't get a particularly good-performing EV.
--
"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 ---
If anyone has a fully functional electric truck available please contact
me. The interested person would be willing to replace old batteries but
does not want a fixer-upper or junker. An S10 was mentioned as a
possibility if there is one out there for sale.
Thanks for any contacts.
Gail
--- End Message ---
--- Begin Message ---
----- Original Message -----
From: "Lee Hart" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Tuesday, January 04, 2005 2:04 PM
Subject: Re: Motors in series? Torque vs. power?
<Snipped>
We don't normally switch series fields in series/parallel because their
resistance is so low that the switches used have as much (or more)
resistance. So, variations in the switch resistance cause the current in
the different field coils to divide unequally. This causes efficiency
and arcing problems.
--
"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, would some kind of solid state switching device be practical and not
have the problems that I assume is caused by contactor use? DC.
Lee A. Hart 814 8th Ave N Sartell MN 56377 leeahart_at_earthlink.net
--- End Message ---
--- Begin Message ---
Bill Dennis wrote:
> Has anyone looked at TS cell balancing via shared transformers?
> The document claims that the balancing would occur quickly, and
> the control logic doesn't seem to be complex. Balancing would
> also appear to occur during charging and discharging.
Yes, it can work well.
I am basically using Fig.6 in my Battery Balancer. The MOSFET, diode,
transformer, and control logic are a Vicor Batmod DC/DC and a BASIC
Stamp micro. The relays are one DPST per battery. It's documented at
http://www.geocities.com/sorefeets/balancerland/
I'm using Fig.7 in a flashlight, with four Hawker Cyclon 2v 2.5ah cells.
The transformer is just a 60 hz power transformer. It has two
secondaries, each with 2 diodes to halfwave charge two cells. It has
worked ok for 20+ years. The drawback of this approach is that the more
cells you have, the harder the transformer gets to design. Small
variations between windings become unmanageable.
Fig.8 has similar problems. Small variations between transformers, and
the effect of all the connecting wiring makes it become impractical with
large numbers of cells. It winds up better to have a complete DC/DC per
cell.
--
"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 ---
Nick Viera wrote:
> 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.
The resistors limit the current no matter which LEDs are lit. So, if the
10ma or so current drain doesn't bother you, you can leave it on. I like
to use it to tell me if my pack really *is* off!
--
"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 ---
On 4 Jan 2005 at 12:07, Lee Hart wrote:
> Small
> window units can be surprisingly frugal.
I wonder how well one will work in a car on a sunny day, though. I seem to
recall reading that the typical automotive air-con has enough capacity to cool
a small house!
True, the EV's air-con doesn't have to fight engine heat; but solar gain can
be huge, and vehicles are notoriously poorly insulated. The automakers
seldom bother with much thermal insulation; for winter the ICE produces all
that waste heat and, for summer, there's plenty of energy on board in the gas
tank.
--- End Message ---
--- Begin Message ---
TiM M wrote:
> I’m looking into adding a DC to DC converter to the
> truck. I’ve found a reasonably priced 29 amp unit from
> Astrodyne, model SD350D-12 for $129 plus shipping.
This looks reasonable. I've had good luck with other Astrodyne products.
I'd call/email them and talk to their tech support. A battery is a
special kind of load; ask them if this unit can drive your accessory
battery. It might be that you can't adjust the output voltage up enough
(to 13.8v for example), or that it will run down the 12v battery if you
don't disconnect it when off, or that it will shut down and not restart
if the output current is too high (can't charge a dead battery).
Also, ask about input fusing and protection when it is powered with a
big battery pack. You need fuses/circuit breakers/thermal cutouts that
can safely interrupt ~100 volts DC.
> Tim McCann
> Electric '61 Corvair Rampside
Cool! I used to have one of those! The center bay is a great place for
batteries.
--
"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 ---
---- Original Message -----
From: "Victor Tikhonov" <[EMAIL PROTECTED]>
To: <ev@listproc.sjsu.edu>
Sent: Tuesday, January 04, 2005 3:38 AM
Subject: Re: Follow-up on Valence Li-Ion batteries in 12V size
> 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.
Ok Victor I will tell it obvious way:
imho TS li-ion cells are UPS batteries, period.
they sag a lot upper C/2 and doesn't like either to be cycled to 80%.
> > 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.
I talk about a $500 test pack not $5000 and not everbody has an automatic
batterie cycler with data log.
> > 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.
"good" EV batteries:
The right horse to put money in and promote EV :^)
> Define "Expensive". That depends on how much money one is
> able and willing to commit to your hobby.
My "expensive" definition is more like:
something you put lots of money in and nothing usable back.
> > 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).
i agree, an assumption is...an assumption, always right to someone and wrong
to other...
In fact i just use Saft definition of discharge rate:
"a traction battery is better quoted at his 1C discharge level"
understandable when you are used to work with 100Ah Saft ni-cad :^)
> > 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.
ok TS 200Ah, let's choose... your car exemple and compare 326V Optima pack
with say about 300V TS pack.
pack price:
$3 500 | $30 000
who will pay that to a company which itself don't know how to charge their
cells ?
so you have immediate range ok, weight gain ok, usable power ok (less than
Optima but usable) BUT it need a lot and BIG TS cells to make it just drive
ok ! look at the price, at the waranty and still unknown life, where is the
real gain here ? i don't have enough money to bet $30 000 or even half this
in batteries !
> 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,
I don't know for USA but in europe, importator/distributor generaly test
product he sell, because he has to warrant it.
So YES i'm disappointed that you or jukka don't make that test, it's not
customer job.
imagine GM selling you a van which had a sticker:
"once you have tested the body resistance in an accident please return the
car to us, we will inspect results and maybe improve the car"
imagine TS cells with a sticker:
"once you have find better way to charge this cell and make them last,
please let we know, we are still looking for it"
> 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.
thank much to them because their experience make lots of people not loosing
big bucks for nothing.
I CRY it here: customer don't have to be a beta tester !
> 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.
>
> How old are you Philippe, may I ask?
no problem Victor,
i'm 30, one 8 old boy and too much EV sitting around (my wife opinion)
though my english should give me near 8 years old :^)
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--- Begin Message ---
If you want to do gear reduction use chain where you can, an English group
did a study on this some years back to determine which oil or grease posed
the least resistance and gave the least loss of energy transfer in bike
chains, in order to test this thoroughly they had to first test a chain with
no grease or oil to determine the base factor for the experiment, what they
found was rather amusing because a chain with no oil or grease presented no
loss and any lubrication added a loss with it, this would tend to make a
chain drive the most efficient, but of course there is the wear factor to
take into consideration.
Garry Stanley
Cable.net.nz
--- End Message ---
--- Begin Message ---
Doug Hartley wrote:
Victor, thanks for the info.
Actually I dug up a plot - result of the test I did comparing
"old" and "new" cell. Old ones still have about the same capacity,
but R_int is higher than for new ones. Here is discharge plot,
I believe, the crude carbon pile load was set to draw 20A.
Both cells weree connected in series for the test to ensure
identical current, and the voltages were moniotored individually
by simple data acquisition system:
http://www.metricmind.com/misc/ts2.gif
Pink line is new cell, green line - the old one.
One of my new cells died, perhaps due to hidden manufacturer's
defect
I suppose that was an "infant mortality" type failure, and once past a
certain number of cycles it is less likely to occur. (said Doug,
hopefully.)
Yes, I believe so. The trick is to be able to detect poential trouble
ones vefire putting them in service (if possible).
This is the sort of problem that worries me about a battery with many
cells paralleled and in series in a closed space. It may be unlikely
for one cell to go bad, but a lot more chance of having a failure with a
lot of cells. Even if that failure doesn't immediately harm the other
cells in parallel, cause a fire, etc., there are now one less cells in
that parallel group to carry the load, so the capacity of the entire
pack is less and the remaining cells have to work harder.
Very valid concern, I can't agre more! I keep trying
to get this poing across to people who is excited to
be able to connect in parallel many cheaper cells to
fine-tune desired capacity and kW/dollar ratio.
Such setup works well until very first failure which
in case of tiny cells well may go unnoticeable.
Only Chinese buses, but they just replace failing ones when
they fail, so some have short life, some long, or so I was told.
This goes against their recommendations of not mixing new cells with
old. I would expect this practice to cause some problems, particularly
if they are not using cell management electronics. But maybe they have
no other practical choice....
If they have 400 cells bus and one cell goes bad, it is
not reasonable to replace 399 others just to have whole
pack with matching manufacture date.
Likewise, if I ruin one cell, I can't justify sending
them whole pack back. What if a month later one more fails?
Speaking of cell management electronics, is there any possibility that
the SCM-200 will be available to fit the 100 Amp.-Hr. cells terminals
bolt spacing (I think it is wider) and also the newer production with
the larger diameter bolts?
SCM will come in versions fitting their most common sizes
including 100Ah ones. Currently only 200Ah cell as highest
runner will have integrated BMS to fit. Once main controller
software charges the way I wanted, resizing the modules to fit
different cells is trivial; with SMT components there is plenty
of room.
BTW, 12V and 6V version (for NiCd) is very easy to make too,
mainly for monitoring and visualizing the battery status
rather than doing something to it. But it will balance
PbA or NiCd pack as well, it is just not *that* strictly
nesessary.
90% of the value of the system is you can see on your dash
how each cell/battery is doing while you drive.
You can always take care of the problem manually as long
as you're informed on time. Most of people's troubles
with batteries could have beed prevented if "they only knew"
it's coming.
As of TS, eventually they will stop selling loose cells at all.
Jukka and I will have black box solution for EVers so no user
will mess with a BMS. Sort of Zebra approach. This already
being installed on the wheel chair type systems. I want to
work out bugs there first.
Thanks,
Best Regards,
Doug
Victor
'91 ACRX - something different.
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--- Begin Message ---
Victor, thanks for your replies and the plot of your comparative cells test.
That plot really shows a significant difference in internal resistance, and
gives an idea of the extra cell heating and loss of power available to the
load, that must occur with the older cells.
I am very impressed with the functionality of the SCM BMS modules and
displays. This looks like a very competant and useful product. I will be
interested to learn about cost and availability date, when determined.
So far I have zero failures or indication of less performance of any cell.
However I might see more signs of weakness, if I could see more. (of what is
happening at individual cells while driving, with your BMS). I am maybe an
exception of being a new EVer who didn't murder his first pack - the first
14 GC batteries worked well for 2 years and then were retired this summer,
still in good operating condition, to house-backup-power duty, 12 in series
parallel for a 24VDC input sine wave inverter. Maybe my early experiences
in the late sixties and early 70's with lead acid and Nicad batteries for
fire alarm systems helps me get along well with them. However, batteries
are not animals, even if they occasionally seem to behave that way.
Sometimes it just takes one mistake or being distracted to have bad
consequences, if there is not good automatic and intelligent electronics
helping.....
As of TS, eventually they will stop selling loose cells at all.
Jukka and I will have black box solution for EVers so no user
will mess with a BMS. Sort of Zebra approach. This already
being installed on the wheel chair type systems. I want to
work out bugs there first.
Interesting....
Thanks.
Best Regards,
Doug
--- End Message ---
--- Begin Message ---
On 4 Jan 2005 at 22:36, Philippe Borges wrote:
> imagine TS cells with a sticker:
> "once you have find better way to charge this cell and make them last,
> please let we know, we are still looking for it"
That's what the higher price of those other batteries buys. You are paying the
salaries of a shop full of engineers, so they can develop a charging regimen
for you.
If you buy your new computer at the local authorized dealer, you'll get full
support.
Maybe they will come out to your house and fix the problems. Of course you pay
a high price for this, but if your time is worth $100 an hour and you know
nothing
about computers, then it is worth it to you.
If you buy the computer at the big box store, you'll get return privilege and
that's
about all. You will pay a moderate price. For lots of people who have some
spare
time, and know something about computers, but are not "gurus," this is fine.
If you buy the computer from a surplus dealer on Ebay, you get little or no
support.
It came with a virus on the hard drive? Too bad! You got a cheap price, so
use
your time to figure out what's wrong and fix it. If your time is worth $10 an
hour, or
if you're a good enough hacker to fix it in a few minutes - your computer is
^still^
cheap. You took a chance, and maybe you got a deal.
It's almost the same with advanced EV batteries. Except right now we are in
something more like the early days of microcomputers, when there were
breathtakingly expensive premade systems for businesses, and relatively cheap
but utterly unsupported kits for hobbyists.
If you have an engineering background, and you're curious about lithium cells;
or if
you have a good head for research and more free time than money; then you are
like the early micro users. Maybe you buy TS. You hope you can figure out an
acceptable charging regimen, homebrew the BMS, and make them work for your
EV. If you can't - well, you had some fun trying.
But if you're a less sophisticated EVer, or you just want your EV to take you
to
work and back with a minimum of fuss, you're more like those early business
computer users. You buy something that's fully supported by dealer or
manufacturer, maybe Valence. You pay a lot more, but you have something you
can use right out of the box.
The rest of us? We're still waiting for lithium EV batteries to reach the
point where
there's some equivalent of the big box store. <g>
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