EV Digest 2413

Topics covered in this issue include:

  1) Re: Reality Check on Nimh Batteries
        by josh <[EMAIL PROTECTED]>
  2) Re: LED Low Voltage was (Red: Cheap LCD Voltmeter)
        by "Christopher Meier" <[EMAIL PROTECTED]>
  3) Ferro charger mods, Personal Transport Module, Pedal Power Cycle Chair.
        by jerry dycus <[EMAIL PROTECTED]>
  4) Re: VW donor questions
        by Paul G <[EMAIL PROTECTED]>
  5) Re: Sacramento Racing, pics and story.
        by Otmar <[EMAIL PROTECTED]>
  6) Re: Rolling Resistance When Wet?
        by "1sclunn" <[EMAIL PROTECTED]>
  7) Re: evercel
        by "Ralph Merwin" <[EMAIL PROTECTED]>
  8) Re: VW donor questions
        by michael bearden <[EMAIL PROTECTED]>
  9) Re: Ferro charger mods, Personal Transport Module, Pedal Power Cycle Chair.
        by "Joe Smalley" <[EMAIL PROTECTED]>
 10) OT: Hey - are hybrids a "crock"?
        by Martin Jackson <[EMAIL PROTECTED]>
 11) Re: Reality Check on Nimh Batteries
        by josh <[EMAIL PROTECTED]>
 12) Re: A familiar SAD story makes it to AUTOWEEK MAG.
        by "Johanna and Stan" <[EMAIL PROTECTED]>
 13) Re: Advanced Batteries - Li-Ion Musings
        by "Dave Davidson" <[EMAIL PROTECTED]>
 14) Re: Advanced Batteries - Li-Ion Musings
        by Rod Hower <[EMAIL PROTECTED]>
 15) (no subject)
        by "Chuck Alldrin" <[EMAIL PROTECTED]>
 16) Toyota's Amazing NiMH batteries
        by John Wilson <[EMAIL PROTECTED]>
 17) Re: Toyota's Amazing NiMH batteries
        by josh <[EMAIL PROTECTED]>
 18) Rudman Regs a Poem.
        by "Lawrence Rhodes" <[EMAIL PROTECTED]>
 19) Re: evercel
        by Lee Hart <[EMAIL PROTECTED]>
 20) Re: Reality Check on Nimh Batteries
        by Lee Hart <[EMAIL PROTECTED]>
 21) Re: Advanced Batteries - Li-Ion Musings
        by "Dave Davidson" <[EMAIL PROTECTED]>
--- Begin Message ---
>>A second problem has to do with the Magnecharger. It is not particularly
>>efficient, either. The nimh EV1 thus pays a double penalty in charging
>>efficiency, due to an inefficient charger and having to run the air
>>conditioner while charging.

Note, I seem to be having a problem with my email provider, so this is
a reply to a post that Peter was quoting but which I have not
received:

A third problem that Ken Adelman mentioned is that there is apparently
a conflict between the behaviour which is good for the long-term
preservation of the batteries and behaviour which results in saving
the most energy.  

Apparently, by making sure the batteries are charged 100%, rather than
just 90% or whatever, this is somewhat better for their lifetime.  But
this last little bit of charging or topping-off is done at lower
efficiencies.  (Unless I have misunderstood something about this
conflict).  I do not know what the status of resolving this apparent
conflict is.  With such long-range batteries, one might consider
blowing-off that last bit of topping off, except for the very high
replacement cost of the batteries.  So, one would wish to consider
doing everything that users and manufacturers, working together, find
is the best for the long-term preservation of the batteries.  Since I
may be in error as to what preserves them best, I'd not take my word
for this last point, if a reader who owns NiMh happens to be
researching the matter.
--- End Message ---
--- Begin Message ---
>
> For example, standard zener voltages are 6.8v, 7.5v, 8.2v, etc. The 7.5v
> zener plus the 2.5v LED gives you a 10v threshold. For a 10.5v
> threshold, the series resistor needs to drop an additional 0.5v / 3ma =
> 166 ohms.
>
> > But do I need to have fuses on each pair of wires between the box and
> > the LEDs in the dash rated to break full pack voltage
>
> Yes, you want a fuse or fusible device in each wire. Not so much because
> the zener or LED might fail, but because the wires themselves may get
> accidentally shorted. Real fuses are expensive. For applications like
> this, where the exact fusing current and time aren't important, you can
> use #30 wire as a fuse, or put a 1/4 watt resistor in series with each
> lead.

After you make up all the sets of circuits for each battery (LED, zener,
pot,
fuses, wiring), connect them all to one voltage source set to the threshold
voltage, and adjust all the trim pots so the LED's just light.  Then connect
them to individual batteries.

-Chris
--- End Message ---
--- Begin Message ---
        Hi Joe, Lee and All,
           Thanks for the info. I had thought that
removing the cap would allow the voltage to rise.
--- Lee Hart <[EMAIL PROTECTED]> wrote:
> From: "jerry dycus" <[EMAIL PROTECTED]>
> 
> >      While we're on chargers I have a 50amp/12vdc
> nom
> > ferro charger/ maintainer for yachts.
> >      The problem is I want to use it for quick
> > charging at 25+ amps/28vdc but is a couple volts
> > short.
> >      Can I disconnect the cap ?
> >      If I do I want to put a switch to switch it
> in
> > and out to use it for high and safe charge rates.
> What
> > kind of voltage rating would it need?
> 
> First, I assume you are changing from a 2-diode
> center-tapped secondary
> to a full bridge to raise the output voltage from
> 12vdc to 24vdc.
      For now it's like that but in the future I'll
put a DPST switch to switch output neg between the
bridge rectifier and the transformer centertap to
switch between 12vdc/50amp and 24vdc/25amp nom
outputs.     

> 
> The AC capacitor is part of the regulating circuit.
> You don't want to
> disconnect it completely, or you'll have almost no
> output. But you can
> adjust its value up/down a bit to adjust the output
> voltage. A little
> more capacitance will raise the output voltage.
      I'll try this. I don't need much extra voltage
but now a full charge takes over 24 hrs.
      The goal is a fast charger when the batts are
low, 20/50% SOC for a lot of charge while shopping,
ect, to extend my range to 60/100 miles per day
without having to wait while the batts charge.
      The project is a low speed, Personal Transport
module idea I'm testing/ using now. Currently 30 mile
range at 20 mph. 
      It's a trike with 2- 20" moped tired wheels in
the back, 2-66lb sealed flooded UPS batts and a 2.1hp
GE golfcart motor. 
     Looking for a good, eff, 1hp, 24v PM motor for
it. I believe the GE is too lightly loaded for eff.
Pulls nice wheelies though and pulls a trailer loaded
with plywood, 2x4's from Lowes 7 miles away.
     After the EV part is sorted out a body will be
made. I'll use it for demostrating to Gov , public
that roads should be designed with them in mind.
    Also as an insurance policy for when fuel supplies
get cut, decline as WILL happen in the near future, 
5-8 years from now an as a low cost, non-polluting
transportion solution now.
       
     It's based on a Pedal Power model called the
Cycle Chair used for lightly disabled people and
factory/ wharehouse transport.
      Does anyone have a stock one? I need to know if
the stock motor is 12 or 24vdc?  
     I just took the stock setup, I have 2, for a 24
mile trip. It scoots along nicly at 15 mph on 24 vdc
but the motor is getting hot. But it only used 15 amps
on level ground.   
     These are great little EV's. Going to the store
is a lot faster than a car because you can park right
by the store's door instead of the parking lot dance
with a car. Getting going is a lot faster too.  
      People love it and get lots of question, grins
and thumbs up, great for spreading the word!!!
> > However, this also degrades regulation. If you
only
> need 1-2 volts more,
> you could also use Schottky diodes for the bridge
> rectifier; they have
> about half the voltage drop of silicon diodes, and
> so would raise your
> output about 1 volt. This has the side effect of
> *improving* voltage
> regulation.
      I've never found a good source of 25/50amp
Schottky diodes at a reasonable price. Even 1 volt
would help, cutting charge time to 12hrs about. Any
low cost/ surplus ones out there?
                Thanks,
                   jerry dycus

> -- 
> Lee A. Hart                Ring the bells that still


__________________________________________________
Do you Yahoo!?
U2 on LAUNCH - Exclusive greatest hits videos
http://launch.yahoo.com/u2
--- End Message ---
--- Begin Message ---
Michael wrote:
Ok, so thanks to Steve B. (of Tropica fame) I have a very nice Bradley
body to begin my next EV project.  So a question to you VW aficianados
out there:
The Bradley is made for the pre-Super Beetle VW pan...are there
arguments in favor of going for IRS (independent rear suspension) years
rather than swing-axle years?  What about upgrading brakes to disc?
Any related thoughts on what to look for in a donor vehicle?
What about running gear for a fairly high-performance EV?
Any thoughts based on experience are appreciated!
I actually prefer the swingaxle design for simplicity and all oiled ball bearing design. With the Bug engine in the back they are mildly twitchy, with anything heavier way in the back they can get downright dangerous (so where are you planning to put batteries).

My EV Buggy with no batteries behind the rear tyres (and the motor is lighter than the engine it replaced) is remarkably stable. I can choose understeer or oversteer heading into a corner, and swinging the back end out doesn't flip the car (if it did I'd be missing from this list - no roll bar or seat belts). The Buggy weighs 1420lbs total, front weight is 605lbs, back 815lbs, so 58% of the weight is still in the back (stock Bug is about 60%, my Buggy when ICE powered was 66% rear and would have been unstable if it didn't understeer so early).

Brakes are touchier. If you plan on it being as heavy or heavier than a stock Bug I recommend at least front disc brakes (easy swap using all factory parts, basically a '69 K-ghia brake system). Remember, changing brakes means changing the master cylinder too. I do not recommend using a single circuit brakes (pre-'67) on any EV as engine braking shouldn't be counted on (well, doesn't even exist without regen). My Buggy is based on a '64 Beetle and the brakes are all stock with the exception of the master cylinder ('67 up Bug). Many kit cars use a '66 down Bus master cylinder because of its built in reservoir. However, its a single circuit system. I came up with a way to use the later Bug cylinder with an attached (Rabbit) reservoir.

Neon
--- End Message ---
--- Begin Message ---
At 9:31 PM +0000 11/4/02, John Bryan wrote:

	She's lighter than you and more caliphageous too.  :^)

Hey, John. This is Rane.  You couldn't even see my butt in those photos!  ;-)

But, thank you anyway.

Rane
--- End Message ---
--- Begin Message ---
I notice about a 5 to 25 % increase in power used when raining .  I have
seen the same increase when the wind is blowing at  me. I bet that even the
out side temp might make a little difference (cold air thicker than warm).
I can tell the difference when giving somebody a ride .     5% increase in
weight means 5% more power. instead of using 100 to go 45 mph I use 105 .
----- Original Message -----
From: "Thomas Shay" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Friday, November 08, 2002 11:16 PM
Subject: Rolling Resistance When Wet?


> A recent discussion with a friend raised the question about
> how rain affects rolling resistance.  I'm sure that heavy rain
> does increase drag, but I don't  know how much.
> Has anyone seen objective data about this?
>
>
--- End Message ---
--- Begin Message ---
Cliff Rassweiler writes:
> 
> I have detailed a pretty easy, not too expensive way of making short but
> flexible cables on www.ProEV.com. Look under Electric Imp, Work History, Nov
> 11-building the battery connectors. The car is not running yet, so I do not
> have experience with how they work long term, but they are basically copied
> from techniques others have used and posted to the list.

Cliff,

Nice looking connectors (and nice web page too).  Are you going to have the
copper parts plated or tinned?  I found that my copper buss bars got fairly
corroded within a month of installing them.  I cleaned all the buss bars and
had them tin plated, and had no more corrosion problems.

Ralph
--- End Message ---
--- Begin Message ---

Paul G wrote:

> I actually prefer the swingaxle design for simplicity and all oiled
> ball bearing design. With the Bug engine in the back they are mildly
> twitchy, with anything heavier way in the back they can get downright
> dangerous (so where are you planning to put batteries).

What does a typical air-cooled VW engine weigh?
And, to answer Neon's question, I am going to have to put batteries in
every available space in order to get the performance that I would be
looking for.
Is this another argument in favor of IRS?
 More donor questions-
I once swapped a 67'Ghia front end into a '66 bug to get the disc brakes.
Are the Ghia and bug pans the same size?  What year did Ghia start with the
disc brakes?
Thanks-
Michael B.
--- End Message ---
--- Begin Message ---
You can modify the output of the transformer slightly by putting a few more
secondary turns on the core.

To increase the voltage/current, put the additional turns in series with the
existing secondary so the voltages add.

To decrease the voltage/current, put the additional turns in series with the
existing secondary so the voltages subtract.

I raised my Lester voltage enough to get it to work with my AGMs this way.

Joe Smalley
Rural Kitsap County WA
Fiesta 48 volts
NEDRA 48 volt street conversion record holder
[EMAIL PROTECTED]


----- Original Message -----
From: "jerry dycus" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Saturday, November 09, 2002 10:27 AM
Subject: Ferro charger mods, Personal Transport Module, Pedal Power Cycle
Chair.


>         Hi Joe, Lee and All,
>            Thanks for the info. I had thought that
> removing the cap would allow the voltage to rise.
> --- Lee Hart <[EMAIL PROTECTED]> wrote:
> > From: "jerry dycus" <[EMAIL PROTECTED]>
> >
> > >      While we're on chargers I have a 50amp/12vdc
> > nom
> > > ferro charger/ maintainer for yachts.
> > >      The problem is I want to use it for quick
> > > charging at 25+ amps/28vdc but is a couple volts
> > > short.
> > >      Can I disconnect the cap ?
> > >      If I do I want to put a switch to switch it
> > in
> > > and out to use it for high and safe charge rates.
> > What
> > > kind of voltage rating would it need?
> >
> > First, I assume you are changing from a 2-diode
> > center-tapped secondary
> > to a full bridge to raise the output voltage from
> > 12vdc to 24vdc.
>       For now it's like that but in the future I'll
> put a DPST switch to switch output neg between the
> bridge rectifier and the transformer centertap to
> switch between 12vdc/50amp and 24vdc/25amp nom
> outputs.
>
> >
> > The AC capacitor is part of the regulating circuit.
> > You don't want to
> > disconnect it completely, or you'll have almost no
> > output. But you can
> > adjust its value up/down a bit to adjust the output
> > voltage. A little
> > more capacitance will raise the output voltage.
>       I'll try this. I don't need much extra voltage
> but now a full charge takes over 24 hrs.
>       The goal is a fast charger when the batts are
> low, 20/50% SOC for a lot of charge while shopping,
> ect, to extend my range to 60/100 miles per day
> without having to wait while the batts charge.
>       The project is a low speed, Personal Transport
> module idea I'm testing/ using now. Currently 30 mile
> range at 20 mph.
>       It's a trike with 2- 20" moped tired wheels in
> the back, 2-66lb sealed flooded UPS batts and a 2.1hp
> GE golfcart motor.
>      Looking for a good, eff, 1hp, 24v PM motor for
> it. I believe the GE is too lightly loaded for eff.
> Pulls nice wheelies though and pulls a trailer loaded
> with plywood, 2x4's from Lowes 7 miles away.
>      After the EV part is sorted out a body will be
> made. I'll use it for demostrating to Gov , public
> that roads should be designed with them in mind.
>     Also as an insurance policy for when fuel supplies
> get cut, decline as WILL happen in the near future,
> 5-8 years from now an as a low cost, non-polluting
> transportion solution now.
>
>      It's based on a Pedal Power model called the
> Cycle Chair used for lightly disabled people and
> factory/ wharehouse transport.
>       Does anyone have a stock one? I need to know if
> the stock motor is 12 or 24vdc?
>      I just took the stock setup, I have 2, for a 24
> mile trip. It scoots along nicly at 15 mph on 24 vdc
> but the motor is getting hot. But it only used 15 amps
> on level ground.
>      These are great little EV's. Going to the store
> is a lot faster than a car because you can park right
> by the store's door instead of the parking lot dance
> with a car. Getting going is a lot faster too.
>       People love it and get lots of question, grins
> and thumbs up, great for spreading the word!!!
> > > However, this also degrades regulation. If you
> only
> > need 1-2 volts more,
> > you could also use Schottky diodes for the bridge
> > rectifier; they have
> > about half the voltage drop of silicon diodes, and
> > so would raise your
> > output about 1 volt. This has the side effect of
> > *improving* voltage
> > regulation.
>       I've never found a good source of 25/50amp
> Schottky diodes at a reasonable price. Even 1 volt
> would help, cutting charge time to 12hrs about. Any
> low cost/ surplus ones out there?
>                 Thanks,
>                    jerry dycus
>
> > --
> > Lee A. Hart                Ring the bells that still
>
>
> __________________________________________________
> Do you Yahoo!?
> U2 on LAUNCH - Exclusive greatest hits videos
> http://launch.yahoo.com/u2
>
--- End Message ---
--- Begin Message ---
Lock Hughes wrote:
> Our testing showed that the Prius derived between 3%
> (highway cycle) and 10% (city and US06) of its propulsion energy from
> the battery pack
...
> The Insight derived between 1% (highway cycle) and
> 3% (US06) of its propulsion energy from the pack.

  Alan Batie <[EMAIL PROTECTED]> wrote:

"Rather than a crock, I think it shows dramatic promise for them, which
isn't so great for those of us who want pure EVs...  If these statistics
are true, it shows that the big engines we like really are just for quick
starts and you don't really need much power beyond that."

  This is a misread of the information. Extra Energy capacity is needed
  for mountain passes, towing and avoidance of full charge and full
  depletion of the batteries. PbA can't be used without regular full
  charge, but NiMH can, and the efficiency of charging is higher in the
  middle DoD range. Further, given the Power required, the batteries
  must be 'oversized' for Energy. This has no negative connotation for
  an EV. Sheer points out that a goal is 100,000 miles life.

"I still wonder if a hydraulic or pneumatic system wouldn't end up being
cheaper and more efficient than electric - but nonetheless, my point
remains."

  This has been looked at by USCAR and Ford, but off the top, I don't
  think it will prove more effective. The pump/motor and accumulator
  will be just as big and more like a supercapacitor than a battery -
  not all bad, but non linear power.

"If by using a very tiny amount of energy stored in a battery you
can avoid wasting a large amount of energy stored in dead dinos, then by
all means you should do it."

  The improved fuel efficiency in the system comes from the lower power,
  lower rpm, and no fuel rich enrichment acceleration power used in the
  hybrid. Without the battery/motor, you couldn't sell the car.

  josh <[EMAIL PROTECTED]> wrote

> Ed Ang wrote:
>Although this is still much better than the 18.2% we
>get from a modern ICE

  Note: 12 % around town

"While ICE engines are often less than 30 or 40% efficiency, I'll have
to go to that link to check where you got the 18.2%."

  It comes from operating the ICE in low power at throttled cruise and
  enriched accelerations mostly.
  ______________________________________________________________________
--- End Message ---
--- Begin Message ---
>Besides, what is the point of having NiMH batteries if you always keep 
>them partially discharged?  You example (25%-75%) would mean that you 
>were only using 50% of their capacity.  If that's the case use PbA for 
>your normal trips and rent a Ferrari with the money you saved on those 
>occasional longer trips.

I think for a home-builder of an EV, the high cost of NiMh might prove
prohibitive, though this simple 50% capacity argument would sway me
from at least considering them.

NiMh has come down in price over the years at the smallest levels, and
although we are continually reminded that the batteries are not the
same for cars, some of the principles might apply if not all of them.
For example, I remember buying NiMH for a camera when it was a bit
pricy, and I never regretted it, it was such a relief to have that
much more capacity.  That said, I think the price for cars right now
is very high.

I wish I knew more as to what part of this price is inherent to NiMh
chemistry and manufacturing, and what part is part of the calculations
economics of expansion of manufacturing of NiMh traction batteries.

I think it could be argued that GM succesfully held up some good
portion of the progress that could have been made, but apparently in
part was not, in the price and availability of NiMH, in their
not-apparently-terribly-enthusiastic affect on Ovonics when they were
part-owners.  My initial take on things, now that GM has more or less
transferred that percentage stake to Chevron-Texaco for a couple of
years or so, is that C-Tis not exactly attempting to move things along
as though there's a war on and the country might benefit from an
advanced pace of progress on this point.  I think they are
concentrating on hybrids.  I'm not sure what their sense of pace is.

At this rate, one of the Lithium Chemistries looks like it might
become economically competitive, by the time NiMH is "ready" for EV's
and hybrids.
--- End Message ---
--- Begin Message ---
    EV1 Owners:

  Another possible solution to shipping out of the country:

  Do what people did in the 70s to avoid the Repo Man:

  Pimp em out.  Probably work as well on an EV1 as on a Cadallic.

  Stan the Spray Can Man.



  ----- Original Message -----
From: "Steven S. Lough" <[EMAIL PROTECTED]>
To: "EV Discussion List Receiver" <[EMAIL PROTECTED]>;
<[EMAIL PROTECTED]>
Sent: Saturday, November 09, 2002 9:13 AM
Subject: A familiar SAD story makes it to AUTOWEEK MAG.


> A freelance auto writer friend of mine, Terry Parkhurst sent me this
> "heads-up" .  Although we are all aware of this on the EV Discussion
> List already,  and lots of bandwidth has been taken up discussing it,  I
> am glad it made it to the auto press.
>
> Terry's message follows:
>
> Steve !  Read this; it is just unf#@%$ingbelievable. I can't understand
> why GM
> won't let these folks buy their EV1s. I hope as many people as can,
> ship them outside the states. Reading this made me lose all respect
> for GM management. There's really no guts there. It's all about
> short-term profit. You were probably better off never to go back to
> Detroit, Steve. - Terry
>
> Article snippit:
>
> Pulling the plug: GM's decision to end electric vehicle leases comes
> as a shock to EV1 enthusiasts
>
> Greg Hanssen's story is a familiar one. He leased his dream car. He
> drove it all over the country and documented his trips on his Web
> site. He made friends because of the car. He worked on it, tinkered
> with it, and improved it. He even leased a second one. The car
> became a part of his identity. But tragically for Hanssen, it isn't
> a 911, a Mustang or a Miata for which his passion burns, but General
> Motors' electric car, the EV1. In February, GM notified EV1 lessees
> that it wouldn't be extending their leases when they begin expiring
> this winter.
>
> Full article and pictures can be seen at:
> http://autoweek.com/cat_print.mv?content_code=03541646
> --
> Steven S. Lough, Pres.
> Seattle EV Association
> 6021 32nd Ave. N.E.
> Seattle,  WA  98115-7230
> Day:  206 396-9189
> Eve:  206 524-1351
> e-mail:  [EMAIL PROTECTED]
> web:     http://slough1.home.mindspring.com/seva.html
>
--- End Message ---
--- Begin Message --- Victor,

Great that you may start carrying them. Will you be getting the Thunder-sky cells/batteries or from a different supplier?

How much do you know about the BMS built into the 36 and 42 volt monoblocks? My fear is that they are designed for the new cars coming out with the higher voltage system and are not made to be strung in series. I figure they can't talk to each other, much less to a control system. I hope I'm wrong as that would tremendously simplify things.

My desire is to build a car with the most range I can get. I plan to retire in a few years and start touring with a motor home. I want my tag-a-long to be a BEV and it looks like I'll have to build one to get what I want. I'll be using it to go wherever I want from the RV park and will probably only be able to charge from the RV park except when I come to CA. My TEVan meets my needs now, but won't for travelling. Plus it's beginning to show it's age and needs almost constant tinkering.

I figure if I can fit in as many 200AH cells as your system can handle, I should have phenominal range. I wish I could get a RAV4 EV, but that appears out of the question unless Toyota wakes up and offers them nationwide.

I'm probably 2 to 3 years away from building my dream car, but am learning as much as I can so I can do a first-class job. I can probably match the RAV4 range with the NiZn, but would like to do better if I can.

Many thanks,

Dave Davidson
Laurel, Maryland
1993 Dodge TEVan



From: Victor Tikhonov <[EMAIL PROTECTED]>
Reply-To: [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Subject: Re: Advanced Batteries - Li-Ion Musings
Date: Fri, 08 Nov 2002 13:44:32 -0800

Dave Davidson wrote:
>
Hi Dave and all, some comments inserted

> I finally got through the Li-Ion references someone had posted earlier as
...
> 100% SOC is listed as 4.2 to
> 4.25 volts depending on your reference. If you stop charging a cell at 4.15
> volts (and never exceed 4.15 volts, even during regen), the cell should stay
> happy.

They have been tested up to 5.04V per cell (10 Ah cell). Other than
rising
temp there was no other immediate effect. Long term damage (shorter
cycle life) after overcharge was not discussed though.

> A cell regulator would have to either be able to pass the entire
> amount of current the charger can produce or else talk to and throttle back
> the charger when the first cell hits 4.15 volts or slightly before,
> progressively reducing current as the voltage comes up.

There are several approaches BMS can handle that, you described
one of them well.

> Either build the
> smarts into the PFC-20/50 or control it with an onboard laptop computer,
> which may be needed anyway.

And make its interface standard, else the only hardware PFC can talk to
will be Rudman regs, which is quite limiting user's choices.

> On the discharge side, Li-Ion cells donít like really heavy currents,
> particularly at lower SOC, and the lowest voltage a cell can be pulled to is
> fairly critical.

Up to 3C is fine, or 600A for 200 Ah cells.

> Have seen this to be anywhere from 2.5 to 2.8 volts. This
> would require that the controller reduce the current limit as the pack
> voltage started sagging. I donít remember if the Seimans system can be set
> up to do this automatically,

Yes, this is its standard feature. You don't need a laptop in your EV.

>
> Only other item needed is a thermal management system to keep the cells from
> getting too hot, or possibly too cold. This would be the easiest part.

This is a part of decent BMS. Since most of the components are water
cooled,
the "infrastructure" is there.

> So, gang, if money were no object (yeah, right), would a setup like this
> work?

Sure, it's been demonstrated (not in the US).

A decent pack may cost about $15k. To me it is better option than
NiZn discussed, but this is matter of taste :-)

> What have I left out? Anyone want to donate the Li-Ion cells for me
> to play with?

I may have them for sale soon. I doubt Thunder-sky will donate any.
Their main US distributor (Worley energy cells) doesn't.
I have ordered couple 100 Ah "to play with". Will post more when new
info will be available. I need to decide which ones are best fit
to complete AC system kit.

FYI, 36V and 42V batteries come with BMS, and can be assembled
with either 50 Ah or 100 Ah cells.

> Dave Davidson
> Laurel, Maryland
> 1993 Dodge TEVan
>
> _________________________________________________________________
> The new MSN 8: smart spam protection and 2 months FREE*
> http://join.msn.com/?page=features/junkmail

_________________________________________________________________
Add photos to your e-mail with MSN 8. Get 2 months FREE*. http://join.msn.com/?page=features/featuredemail
--- End Message ---
--- Begin Message ---
Dave,
When you get tired of tinkering with the TEVan let me know.
I would like a back up vehicle.
I'm in the process of designing a motor control test fixture
to get another TEVan on the road.
I plan on finishing this project before December, I know the
Tevan owner is getting frustrated waiting for a motor control
fix.
My Tevan is still doing fine, drove 35 miles today running errands
and transporting 'stuff' in the cargo space a minivan offers.
Rod.

Dave Davidson wrote:
Victor,

Great that you may start carrying them. Will you be getting the Thunder-sky cells/batteries or from a different supplier?

How much do you know about the BMS built into the 36 and 42 volt monoblocks? My fear is that they are designed for the new cars coming out with the higher voltage system and are not made to be strung in series. I figure they can't talk to each other, much less to a control system. I hope I'm wrong as that would tremendously simplify things.

My desire is to build a car with the most range I can get. I plan to retire in a few years and start touring with a motor home. I want my tag-a-long to be a BEV and it looks like I'll have to build one to get what I want. I'll be using it to go wherever I want from the RV park and will probably only be able to charge from the RV park except when I come to CA. My TEVan meets my needs now, but won't for travelling. Plus it's beginning to show it's age and needs almost constant tinkering.

I figure if I can fit in as many 200AH cells as your system can handle, I should have phenominal range. I wish I could get a RAV4 EV, but that appears out of the question unless Toyota wakes up and offers them nationwide.

I'm probably 2 to 3 years away from building my dream car, but am learning as much as I can so I can do a first-class job. I can probably match the RAV4 range with the NiZn, but would like to do better if I can.

Many thanks,

Dave Davidson
Laurel, Maryland
1993 Dodge TEVan



From: Victor Tikhonov <[EMAIL PROTECTED]>
Reply-To: [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Subject: Re: Advanced Batteries - Li-Ion Musings
Date: Fri, 08 Nov 2002 13:44:32 -0800

Dave Davidson wrote:
>
Hi Dave and all, some comments inserted

> I finally got through the Li-Ion references someone had posted earlier as
...
> 100% SOC is listed as 4.2 to
> 4.25 volts depending on your reference. If you stop charging a cell at 4.15
> volts (and never exceed 4.15 volts, even during regen), the cell should stay
> happy.

They have been tested up to 5.04V per cell (10 Ah cell). Other than
rising
temp there was no other immediate effect. Long term damage (shorter
cycle life) after overcharge was not discussed though.

> A cell regulator would have to either be able to pass the entire
> amount of current the charger can produce or else talk to and throttle back
> the charger when the first cell hits 4.15 volts or slightly before,
> progressively reducing current as the voltage comes up.

There are several approaches BMS can handle that, you described
one of them well.

> Either build the
> smarts into the PFC-20/50 or control it with an onboard laptop computer,
> which may be needed anyway.

And make its interface standard, else the only hardware PFC can talk to
will be Rudman regs, which is quite limiting user's choices.

> On the discharge side, Li-Ion cells donít like really heavy currents,
> particularly at lower SOC, and the lowest voltage a cell can be pulled to is
> fairly critical.

Up to 3C is fine, or 600A for 200 Ah cells.

> Have seen this to be anywhere from 2.5 to 2.8 volts. This
> would require that the controller reduce the current limit as the pack
> voltage started sagging. I donít remember if the Seimans system can be set
> up to do this automatically,

Yes, this is its standard feature. You don't need a laptop in your EV.

>
> Only other item needed is a thermal management system to keep the cells from
> getting too hot, or possibly too cold. This would be the easiest part.

This is a part of decent BMS. Since most of the components are water
cooled,
the "infrastructure" is there.

> So, gang, if money were no object (yeah, right), would a setup like this
> work?

Sure, it's been demonstrated (not in the US).

A decent pack may cost about $15k. To me it is better option than
NiZn discussed, but this is matter of taste :-)

> What have I left out? Anyone want to donate the Li-Ion cells for me
> to play with?

I may have them for sale soon. I doubt Thunder-sky will donate any.
Their main US distributor (Worley energy cells) doesn't.
I have ordered couple 100 Ah "to play with". Will post more when new
info will be available. I need to decide which ones are best fit
to complete AC system kit.

FYI, 36V and 42V batteries come with BMS, and can be assembled
with either 50 Ah or 100 Ah cells.

> Dave Davidson
> Laurel, Maryland
> 1993 Dodge TEVan
>
> _________________________________________________________________
> The new MSN 8: smart spam protection and 2 months FREE*
> http://join.msn.com/?page=features/junkmail


_________________________________________________________________
Add photos to your e-mail with MSN 8. Get 2 months FREE*. http://join.msn.com/?page=features/featuredemail


--- End Message ---
--- Begin Message ---
which
--- End Message ---
--- Begin Message --- Toyota's RAV 4 EVs are reaching 100,000 miles using their original battery packs, according to this article posted on EV World. Here's a clip from that article:

"SCE Electric Vehicle Reaches 100,000-Mile Milestone

LOS ANGELES, Nov. 7 /PRNewswire/ -- The odometer on one of Southern California Edison's (SCE) electric vehicles (EVs) rolled over to 100,000 miles today -- the farthest any plug-in EV anywhere has traveled in real-world driving applications."

Too bad us hobbyists can't get those batteries...

Jay
--- End Message ---
--- Begin Message ---
On Sat, 9 Nov 2002 21:05:01 -0800, you wrote:

>Toyota's RAV 4 EVs are reaching 100,000 miles using their original 
>battery packs, according to this article posted on EV World. Here's a 
>clip from that article:
>
>"SCE Electric Vehicle Reaches 100,000-Mile Milestone
>
>LOS ANGELES, Nov. 7 /PRNewswire/ -- The odometer on one of Southern 
>California Edison's (SCE) electric vehicles (EVs) rolled over to 100,000 
>miles today -- the farthest any plug-in EV anywhere has traveled in 
>real-world driving applications."
>
>Too bad us hobbyists can't get those batteries...
>
>Jay

For many years I've been hoping that Matsushita's continued
manufacturing of such batteries was a slight glimmer of hope as
against Ovonics' obvious foot-dragging.  Maybe, I thought, this is a
sign that a world-class manufacturer is somewhat committed to at least
exploring this technology.  And then we had other nearby related
slight-glimmers, such as the few-years-old sarcastic quote of
frustration by some Detroiter that at the time the cheapest way for
them to get a NiMH pack was to buy a RAV4 and throw away the car and
keep the (very expensive but comparatively inexpensive) battery.
Also, we had the lawsuits against Matsushita, and others, by Ovonic,
for patent infringement.   At least they were gettings Ovonic's
attention, and producing enough to warrant a suit.

With recent improvements in Lithium-whatever, I'm hopeful that this
additional factor  will slightly turn up the heat on the committed
foot-draggers that they can't quite keep the lid on the box anymore
(if that's what they've been doing), so maybe they ought consider just
throwing their hat in the ring and trying harder to make better
affordable advanced batteries.  But this is probably a naive hope.
It's a lot easier to say "affordable available super Lithium-whatever
battery" than to do it.  I'll believe it when I see it.

Years ago I saw one EV-leaser and fellow industry critic put his view
on this, which is that he thought basically the Japanese were playing
ball (keeping the lid on EV's), but didn't quite see it as cynically
as Detroit, and so they were somewhat more inclined to build a decent
EV than was Detroit, and they would occassionally "bust loose" and do
something they weren't supposed to do.  I'm hopeful that, with every
RAV4 that is made, and with every battery pack that Matsushita makes
(I think it's them anyway) that they gain experience and knowledge,
and just leave Detroit in the dust, and maybe, finally, convince
themselves that if battery packs can indeed be made affordable that
the overall vehicle is worth continuing.  

Until they are able to make the battery packs affordably, I don't
think they'll really make any concrete plans for such production.
They'll continue to have the luxuries of the excuses of saying it's
too expensive or that the demand isn't quite there (of course it's not
quite there, with those prices and problems of expensive pack
replacement, etc.).  

Not that I enjoy seeing the US fall behind in anything, but I think
that's already inevitable in EV's and related technologies, and the
larger issue of continued development of better-mileage better-fuel
vehicles will simply be lost if the Japanese and others, outside of
Oil-throttled Detroit, do not continue to press these issues, IMO.
--- End Message ---
--- Begin Message ---
Well they do there job but the climate changes. Them milder nights make them
crazy.  Just a couple of hundredths up they go and a straggler goes low.
Readjust all thirty and Mr. Ohms law comes to duty.  With no where to go
this little pup comes up.  Like fireflys in the night.  Such a delight.
Flashing like a school of fish or birds in flight.  It's so right.  The
timer clicks and they have their night.  Dialing in is nice but what of the
digital era.  It's enough to make a fellow sweara. The B & W goes one way
Rudman the other. In the cold they go down and the heat they go up.  That's
not the way to train a pup.  Temperature sensitive and feed back hay.
That's the only way,  corrected for temperature OK......Will the Mark III
see this day????  A poem by Lawrence Rhodes....Apologies to every poet ever
born and to anyone else offended....
--- End Message ---
--- Begin Message ---
Cliff Rassweiler writes:
> I have detailed a pretty easy, not too expensive way of making short
> but flexible cables on www.ProEV.com. Look under Electric Imp, Work
> History, Nov 11 - building the battery connectors.

Cliff,

Have you actually tested the resistance and pull strength of your
crimps? I am worried they are not really as good as you might like.

The first problem is that I doubt that your 10-ton press could create
enough pressure to really cold-weld the braided strand to the copper
tube. The surface area is so large that the pressure per square inch
would be too low.

If this is the case, then all you have is a friction fit. You can verify
this by measuring the resistance, while pulling and wiggling on the
strap. If it varies, you have a problem.

You can also dissect one. Trim the copper off the edges. If the upper
and lower pieces will pry off, and the individual strands of the copper
braid will separate, this again proves it is not a cold weld.

What I would do is to flux the ends, and dip them in a solder pot. A wet
rag around the braid just above the joint will prevent solder from
wicking up the braid.

The solder coating will also prevent corrosion if/when a battery leaks
or vents. As Ralph Merwin pointed out, you really don't want bare copper
around battery terminals. Copper corrodes far too quickly around
sulfuric acid.
-- 
Lee A. Hart                Ring the bells that still can ring
814 8th Ave. N.            Forget your perfect offering
Sartell, MN 56377 USA      There is a crack in everything
leeahart_at_earthlink.net  That's how the light gets in - Leonard Cohen
--- End Message ---
--- Begin Message ---
>> Besides, what is the point of having NiMH batteries if you always
>> keep them partially discharged? Your example (25%-75%) would mean
>> that you were only using 50% of their capacity. If that's the case
>> use PbA for your normal trips and rent a Ferrari with the money you
>> saved on those occasional longer trips.

With any type of battery, you'll get longer life if you avoid fully
discharging and overcharging it. You want to design so your daily range
only uses about 50% of the battery's true capacity.

For example, the Toyota Prius uses nimh batteries, and they aggressively
keep them between 50% and 80% SOC, because it helps them to last the
80,000 miles they warranty them for. If they had allowed deeper
discharges, the batteries would be shot in a couple years, and they'd
have to eat the replacement cost (under warranty).

If you need a range of 25 miles a day, and put in a lead-acid pack that
can barely do it when new, then your batteries will be shot in less than
a year. They've still got 90% of their capacity, but it's no longer
enough for your commute.

If you oversize the pack for a 50-mile range, then your daily drive only
discharges it 50%, and the pack will last several years due to the
shallower discharges. You can keep using the batteries until only 50% of
their capacity is left.

But suppose you needed a 50-mile daily range. Your car can't carry
enough lead-acid batteries to achieve a 100-mile range. But with nimh,
you can design for a 100-mile range, and only use 50 miles daily. Now
your expensive nimh pack will last for years.
-- 
Lee A. Hart                Ring the bells that still can ring
814 8th Ave. N.            Forget your perfect offering
Sartell, MN 56377 USA      There is a crack in everything
leeahart_at_earthlink.net  That's how the light gets in - Leonard Cohen
--- End Message ---
--- Begin Message --- Rod,

I'll certainly give you right of first refusal. It never has been anything major, and when running right, I get 45 miles at least before the low pack light comes on. Very seldom take it that far. Mostly to and from the train station, running errands, and hauling the kids around. It's just been nitpicking stuff.

It's latest thing was not wanting to start out in low gear. Did fine (but terribly slow) in high, and was intermittent. Got to where it was moving about 10 feet in low and dying, if it moved at all - had to shift to high to move. The transmission switches checked fine, so I turned my attention to the potbox and microswitch. While trying to take some measurements, the microswitch broke apart. Apparently it had been cracked before. Haven't checked the pot to see if it's dirty and needs to be cleaned or replaced. And, yes, only one pot was connected.

Now I'll have to pull the potbox/pedal assembly out before I can tell anything else. My suspicion is that the controller was thinking that the accelerator was pressed when putting it in gear due to the pot or the microswitch was otherwise fooling it.

If you've come across this before, I'd appreciate any ideas.

Thanks,

Dave




From: Rod Hower <[EMAIL PROTECTED]>
Reply-To: [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Subject: Re: Advanced Batteries - Li-Ion Musings
Date: Sat, 09 Nov 2002 22:24:49 -0800

Dave,
When you get tired of tinkering with the TEVan let me know.
I would like a back up vehicle.
I'm in the process of designing a motor control test fixture
to get another TEVan on the road.
I plan on finishing this project before December, I know the
Tevan owner is getting frustrated waiting for a motor control
fix.
My Tevan is still doing fine, drove 35 miles today running errands
and transporting 'stuff' in the cargo space a minivan offers.
Rod.

Dave Davidson wrote:
Victor,

Great that you may start carrying them. Will you be getting the Thunder-sky cells/batteries or from a different supplier?

How much do you know about the BMS built into the 36 and 42 volt monoblocks? My fear is that they are designed for the new cars coming out with the higher voltage system and are not made to be strung in series. I figure they can't talk to each other, much less to a control system. I hope I'm wrong as that would tremendously simplify things.

My desire is to build a car with the most range I can get. I plan to retire in a few years and start touring with a motor home. I want my tag-a-long to be a BEV and it looks like I'll have to build one to get what I want. I'll be using it to go wherever I want from the RV park and will probably only be able to charge from the RV park except when I come to CA. My TEVan meets my needs now, but won't for travelling. Plus it's beginning to show it's age and needs almost constant tinkering.

I figure if I can fit in as many 200AH cells as your system can handle, I should have phenominal range. I wish I could get a RAV4 EV, but that appears out of the question unless Toyota wakes up and offers them nationwide.

I'm probably 2 to 3 years away from building my dream car, but am learning as much as I can so I can do a first-class job. I can probably match the RAV4 range with the NiZn, but would like to do better if I can.

Many thanks,

Dave Davidson
Laurel, Maryland
1993 Dodge TEVan



From: Victor Tikhonov <[EMAIL PROTECTED]>
Reply-To: [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Subject: Re: Advanced Batteries - Li-Ion Musings
Date: Fri, 08 Nov 2002 13:44:32 -0800

Dave Davidson wrote:
>
Hi Dave and all, some comments inserted

> I finally got through the Li-Ion references someone had posted earlier as
...
> 100% SOC is listed as 4.2 to
> 4.25 volts depending on your reference. If you stop charging a cell at 4.15
> volts (and never exceed 4.15 volts, even during regen), the cell should stay
> happy.

They have been tested up to 5.04V per cell (10 Ah cell). Other than
rising
temp there was no other immediate effect. Long term damage (shorter
cycle life) after overcharge was not discussed though.

> A cell regulator would have to either be able to pass the entire
> amount of current the charger can produce or else talk to and throttle back
> the charger when the first cell hits 4.15 volts or slightly before,
> progressively reducing current as the voltage comes up.

There are several approaches BMS can handle that, you described
one of them well.

> Either build the
> smarts into the PFC-20/50 or control it with an onboard laptop computer,
> which may be needed anyway.

And make its interface standard, else the only hardware PFC can talk to
will be Rudman regs, which is quite limiting user's choices.

> On the discharge side, Li-Ion cells donít like really heavy currents,
> particularly at lower SOC, and the lowest voltage a cell can be pulled to is
> fairly critical.

Up to 3C is fine, or 600A for 200 Ah cells.

> Have seen this to be anywhere from 2.5 to 2.8 volts. This
> would require that the controller reduce the current limit as the pack
> voltage started sagging. I donít remember if the Seimans system can be set
> up to do this automatically,

Yes, this is its standard feature. You don't need a laptop in your EV.

>
> Only other item needed is a thermal management system to keep the cells from
> getting too hot, or possibly too cold. This would be the easiest part.

This is a part of decent BMS. Since most of the components are water
cooled,
the "infrastructure" is there.

> So, gang, if money were no object (yeah, right), would a setup like this
> work?

Sure, it's been demonstrated (not in the US).

A decent pack may cost about $15k. To me it is better option than
NiZn discussed, but this is matter of taste :-)

> What have I left out? Anyone want to donate the Li-Ion cells for me
> to play with?

I may have them for sale soon. I doubt Thunder-sky will donate any.
Their main US distributor (Worley energy cells) doesn't.
I have ordered couple 100 Ah "to play with". Will post more when new
info will be available. I need to decide which ones are best fit
to complete AC system kit.

FYI, 36V and 42V batteries come with BMS, and can be assembled
with either 50 Ah or 100 Ah cells.

> Dave Davidson
> Laurel, Maryland
> 1993 Dodge TEVan
>
> _________________________________________________________________
> The new MSN 8: smart spam protection and 2 months FREE*
> http://join.msn.com/?page=features/junkmail


_________________________________________________________________
Add photos to your e-mail with MSN 8. Get 2 months FREE*. http://join.msn.com/?page=features/featuredemail



_________________________________________________________________
The new MSN 8: smart spam protection and 2 months FREE* http://join.msn.com/?page=features/junkmail
--- End Message ---

Reply via email to