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Discussion Starter #1
Sweet! My truck came in this afternoon! Drove around the neighborhood a
bit and got my first EV grin. Good times.

It's an '84 Chevy S10 w/ curtis 1231, adc 9", 22 nearly dead US-145 6v
batts (the other two from the original 144v pack are totally dead), and
a K&W BC20 charger.

Those last two items bring me to my big question. A quick google of that
charger number gets me a pdf that suggests to me that this charger is
only meant for packs up to 108 volts, or 120 volts with a seperate
buck/boost unit. Am I missing something here, or is this charger totally
inadequate for this pack? Could this be why the batteries are just about
toast now after 7500 EV miles (according to original owner)?

Also, when I drove around briefly this afternoon, I noticed that if I
pushed the throttle to hard (not to say gave it too much gas...) the
volts guage would bottom out and the rear end would shake and bang a
bunch. This seemed bad, and as I drove around it happened at less and
less throttle. Is this just an artifact of a bad pack that can't draw
many amps any more? Or something else? Any insight you guys have would
be good.

This was a good decision. I need batteries, a 12v battery (no headlights
while accellerating ;-) and a power brake kit, and maybe a better
charger, and my grin will be even bigger.

Thanks for the help

Hunter.


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Discussion Starter #2
OK, so I ran the charger for nearly 8 hours and afterward my pack read
145v, vs. the 135 it had when it rolled off the flatbed or 120 when it
limped home banging the rear-end. I was pleasantly surprised, as I
didn't think the BC20 was going to have the juice to get the pack up
there. Maybe I'm not understanding that thing right. But anyway, I
jumped in and went for a drive, and things were much better with the
higher voltage; I could push the throttle all the way without the rear
end slamming, and acceleration was much quicker. The radio still goes
out under accel, but with no aux battery that doesn't surprise me much.

Still interested in what you guys think about the charger...should it be
able to handle this 132v pack? What about a 144v pack when I replace
these dead batteries? Also, how do I know when this thing is finished
charging? Does it just turn off? As I say I plugged it in around 11:30
last night, then unplugged after 6 this morning...the ammeter stayed
right at 6 amps the whole time and it was still whirring away. Is it OK
to leave it unattended while charging? And finally, if the verdict is
that this charger isn't adequate for the pack...have a recommendation
for a good cheap charger? Naturally I'd love to spring for a PFC, but I
just don't think it's in the cards right now...it'd be close to half
what I paid for the whole truck, and I still need batteries and would
like to upgrade to power brakes.

Thanks everybody

Hunter (grinning)



Hunter Cook wrote:
> Sweet! My truck came in this afternoon! Drove around the neighborhood a
> bit and got my first EV grin. Good times.
>
> It's an '84 Chevy S10 w/ curtis 1231, adc 9", 22 nearly dead US-145 6v
> batts (the other two from the original 144v pack are totally dead), and
> a K&W BC20 charger.
>
> Those last two items bring me to my big question. A quick google of that
> charger number gets me a pdf that suggests to me that this charger is
> only meant for packs up to 108 volts, or 120 volts with a seperate
> buck/boost unit. Am I missing something here, or is this charger totally
> inadequate for this pack? Could this be why the batteries are just about
> toast now after 7500 EV miles (according to original owner)?
>
> Also, when I drove around briefly this afternoon, I noticed that if I
> pushed the throttle to hard (not to say gave it too much gas...) the
> volts guage would bottom out and the rear end would shake and bang a
> bunch. This seemed bad, and as I drove around it happened at less and
> less throttle. Is this just an artifact of a bad pack that can't draw
> many amps any more? Or something else? Any insight you guys have would
> be good.
>
> This was a good decision. I need batteries, a 12v battery (no headlights
> while accellerating ;-) and a power brake kit, and maybe a better
> charger, and my grin will be even bigger.
>
> Thanks for the help
>
> Hunter.
>
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev

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Discussion Starter #4
Thanks Dave.

I'm in Springfield, Missouri. The truck was originally from Michigan. I
want just what you guessed, range and normal performance, and have
planned so far to use more 6v floodeds. I thought the regulators were
unnecessary for flooded packs? I heard that AGMs need them because long
strings of them tend to charge unevenly, but that strings of the
floodeds didn't have such problems? How much do "simple" regulators
cost?

While I'm on the subject, does anybody have experience with the
Energizer brand GC2 6v flooded batteries they have at Sam's Club? They
say 230ah on the side, and they're pretty cheap ($62) relative to what
I've seen...but of course I know nothing of their cycle life.
Alternatively, anybody got a recommendation for cheap golf cart
batteries, preferably close to SW Missouri?

Thanks

Hunter.

dave cover wrote:
> Congratulations Hunter, enjoy the ride. Where are you located?
>
> You need to decide how you want to drive your EV to help determine your next
> pack. If you want range and regular performance, the 6v floodeds might be
> the best option. And the charger may be set correctly, but I can't help with
> that. If you want to get more life out of your new batts, you should
> consider regulators, even simple ones help.
>
> Dave Cover
>
>
> On 9/29/07, Hunter Cook <[email protected]> wrote:
> >
> > Sweet! My truck came in this afternoon! Drove around the neighborhood a
> > bit and got my first EV grin. Good times.
> >
> > It's an '84 Chevy S10 w/ curtis 1231, adc 9", 22 nearly dead US-145 6v
> > batts (the other two from the original 144v pack are totally dead), and
> > a K&W BC20 charger.
> >
> > Those last two items bring me to my big question. A quick google of that
> > charger number gets me a pdf that suggests to me that this charger is
> > only meant for packs up to 108 volts, or 120 volts with a seperate
> > buck/boost unit. Am I missing something here, or is this charger totally
> > inadequate for this pack? Could this be why the batteries are just about
> > toast now after 7500 EV miles (according to original owner)?
> >
> > Also, when I drove around briefly this afternoon, I noticed that if I
> > pushed the throttle to hard (not to say gave it too much gas...) the
> > volts guage would bottom out and the rear end would shake and bang a
> > bunch. This seemed bad, and as I drove around it happened at less and
> > less throttle. Is this just an artifact of a bad pack that can't draw
> > many amps any more? Or something else? Any insight you guys have would
> > be good.
> >
> > This was a good decision. I need batteries, a 12v battery (no headlights
> > while accellerating ;-) and a power brake kit, and maybe a better
> > charger, and my grin will be even bigger.
> >
> > Thanks for the help
> >
> > Hunter.
> >
> >
> > _______________________________________________
> > For subscription options, see
> > http://lists.sjsu.edu/mailman/listinfo/ev
> >
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev

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Discussion Starter #5
The BC-20 doesn't shut off, it runs forever. It has some current and
voltage regulation, but not anything that you'd really call charge control.
Its GFI also trips when the batteries get a little dirty and/or damp - and
if you bypass the GFI to stop that nuisance, you have a potentailly
hazardous condition because it doesn't provide isolation from the mains.

AFAIK, it's not suited to batteries over 120 volts. I've used one at 128
volts, but that's about as far as I'd push it.

I'd like to tell you where to find a smart charger that will baby your
batteries and give you the best possible range and costs $100, but there's
no such animal. If you can't even pop for a PFC, which is pretty cheap for
the amount of grunt it has, then you're probably best off to do what you can
with the BC-20. That probably means dropping your pack voltage down to 120
or 108 volts.

If you're not going to use a smart charger, don't get VRR batteries, stick
with flooded batteries. And, again, if cost is a primary consideration,
flooded golf car batteries are the cheapest option. VRRs can easily cost 5-
10 times as much per mile of life.

Enjoy your EV grin!

David Roden - Akron, Ohio, USA
EVDL Administrator

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Discussion Starter #6
Very simple fix, Just install new pack of 144 volt batteries. If you use =

the same US T145's, they require at least 7.5 V charge per battery for a =

normal charge or call bulk charging at a battery temperature of 80 F.

The total charging voltage should be 7.5 V x 24 =3D 180 volts. For a =

equalization charge, the charge voltage is about 7.78 V x 24 =3D 186 volts.

The minimum discharge for these batteries are about 5.5 V per battery or 5.=
5 =

V x 24 =3D 132 volts. So your existing battery charger cannot not even cha=
rge =

at the minimums.

Your battery volt gage should be red line at about 132 volts, where you =

should never go below that voltage. Its best to never take them below 144 =

volts. The setting voltage after charging should be about 6.83 volts or =

6.83 V x 24 =3D 163.9 volts.

When you add a initial load, it is common for these batteries to drop to 6.=
4 =

volts or 6.4 x 24 =3D 153.6 volts. Applying a constant load of not more th=
an =

100 battery amps, the batteries will normally drop to 6.16 volts or 6.16 V =
x =

24 =3D 148 volts.

You can have the battery sag to the 132 voltage low limit, as long it comes =

up to or just above 144 volts. If your batteries are at 144 volts, this is =

about the 50 percent depth of discharge (DOD) which is the minimum your =

batteries should be discharge to.

If the lower DOD is kept at about the 40 to 20 percent range, they will las=
t =

longer. I can get about 10 years, by discharging down to about 25% DOD and =

then do the normal charge, and a equalization charge about once a month or =

when the battery voltage get about of 2 percent of each other.

A good motor design for a EV, is where the name plate voltage of the motor =

would be at the minimum low limit of the batteries which would be at 132 =

volts for a 144 volt pack. Normally motors have a service factor of 1.15 t=
o =

1.5 SF where they can take a over voltage.

My motor has a SF of 1.5 SF, so if is a 130 volt motor, it can take a =

voltage of 130 x 1.5 =3D 195 volts. My motor is rated at 165 volts which i=
s =

the minimum battery low limit on a 180 volt pack, but can run at 225 volts=
. =

My motor has plenty of power, even if the battery pack is down to 165 volts.

If the name plate voltage of the motor is higher than the battery voltage, =

then you may not have the performance you need, but this depends on what =

type of controller you have. The battery voltage could be higher than the =

design motor voltage. With my Zilla by Caf=E9 Electric, I can use up to a 3=
00 =

volt battery pack, but program the voltage limits into it.

As for the battery charger, I like to use a charger that can charge any =

battery voltage from a 12 volt battery to over 400 volts. Use any AC input =

voltage from 60 to 250 VAC at any ampere from 0.001 to 55 amps. Has =

multiple programs for any type of charger level and have input controls for =

equalization regulators or Battery Management Systems (BMS). I do not use =

BMS for my batteries yet, because after 6 years, the batteries are all in =

with 0.02 volts of each other on my T-145's batteries.

This type of charger which is a Power Factor Control type (PFC) can be seen =

at: http://www.manzanitamicro.com

You normally will use a E-meter with this charger. My EV came with a =

separate bank of AC input and DC output meters in a separate rack panel and =

another set on the dash. Using a set of AC input meters, you can see the =

percentage difference between the AC input and DC outputs. If you charge a=
t =

50 amps DC you can actually be on a good magnetic 50 amp circuit breaker, =

where the AC amperes may be at 45 amps which is a 90 percent power factor.

Roland








----- Original Message ----- =

From: "Hunter Cook" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Friday, September 28, 2007 10:53 PM
Subject: [EVDL] I have an EV!!!! (And some questions)


> Sweet! My truck came in this afternoon! Drove around the neighborhood a
> bit and got my first EV grin. Good times.
>
> It's an '84 Chevy S10 w/ curtis 1231, adc 9", 22 nearly dead US-145 6v
> batts (the other two from the original 144v pack are totally dead), and
> a K&W BC20 charger.
>
> Those last two items bring me to my big question. A quick google of that
> charger number gets me a pdf that suggests to me that this charger is
> only meant for packs up to 108 volts, or 120 volts with a seperate
> buck/boost unit. Am I missing something here, or is this charger totally
> inadequate for this pack? Could this be why the batteries are just about
> toast now after 7500 EV miles (according to original owner)?
>
> Also, when I drove around briefly this afternoon, I noticed that if I
> pushed the throttle to hard (not to say gave it too much gas...) the
> volts guage would bottom out and the rear end would shake and bang a
> bunch. This seemed bad, and as I drove around it happened at less and
> less throttle. Is this just an artifact of a bad pack that can't draw
> many amps any more? Or something else? Any insight you guys have would
> be good.
>
> This was a good decision. I need batteries, a 12v battery (no headlights
> while accellerating ;-) and a power brake kit, and maybe a better
> charger, and my grin will be even bigger.
>
> Thanks for the help
>
> Hunter.
>
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
> =


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Discussion Starter #7
Hi Hunter,

And congrats. It's a good thing those batteries are already toast. You'd be putting a major hurting on them driving that way.

The Curtis has a maximum and minimum operating voltage. You are probably dragging the pack below the minimum usable voltage and the controller is cutting back your amps to keep the pack up at the minimum voltage, hence the shake, rattle 'n roll.

Re: Your charger- There was just a long thread on these but I didn't follow it. Check the archives. If the charger proves inadequate, someone may be able to direct you to a 2-charger solution, or if you have more money available you might look at a PFC or a Zivan charger. Russco also makes affordable chargers that will be properly matched to your pack.

When you get your new pack and charger situation worked out, don't pound the throttle. With new batteries after charging, your finishing voltage should be -about- 173 volts. (about 2.4 volts per cell, so 7.2 volts per battery) Your voltage at 80% depth of discharge should be -about- 138 volts.

So that means-

When driving, try very hard not to draw your pack below 138 volts while accelerating, and try not to finish driving below 138 volts.

138 volts works out to 1.91 volts per cell (each batt having 3 cells obviously). You really don't want to pull much lower than that because if you have any cells out of balance, you risk a cell or battery reversal (going below 0 volts, into negative territory). You'll ruin the battery very quickly.

I have a 128 volt pack of 8v batts. Charging finish is 155. For me, the math works out to not go below 115-112 volts. I never accelerate harder than that, and I've never had a finish-driving voltage lower than 128 volts. Even then, I've done it only like twice.

If you knew all of this already, I apologize. If I have said anything incorrect, I hope someone KNOWLEGEABLE steps up and corrects me. ;-)

Cheers,
Rich A.


Message: 31Date: Fri, 28 Sep 2007 23:53:46 -0500From: Hunter Cook <[email protected]>Subject: [EVDL] I have an EV!!!! (And some questions)To: Electric Vehicle Discussion List <[email protected]>Message-ID: <[email protected]>Content-Type: text/plain Sweet! My truck came in this afternoon! Drove around the neighborhood abit and got my first EV grin. Good times. It's an '84 Chevy S10 w/ curtis 1231, adc 9", 22 nearly dead US-145 6vbatts (the other two from the original 144v pack are totally dead), anda K&W BC20 charger. Those last two items bring me to my big question. A quick google of thatcharger number gets me a pdf that suggests to me that this charger isonly meant for packs up to 108 volts, or 120 volts with a seperatebuck/boost unit. Am I missing something here, or is this charger totallyinadequate for this pack? Could this be why the batteries are just abouttoast now after 7500 EV miles (according to original owner)? Also, when I drove aro!
und briefly this afternoon, I noticed that if Ipushed the throttle to hard (not to say gave it too much gas...) thevolts guage would bottom out and the rear end would shake and bang abunch. This seemed bad, and as I drove around it happened at less andless throttle. Is this just an artifact of a bad pack that can't drawmany amps any more? Or something else? Any insight you guys have wouldbe good. This was a good decision. I need batteries, a 12v battery (no headlightswhile accellerating ;-) and a power brake kit, and maybe a bettercharger, and my grin will be even bigger. Thanks for the help Hunter.
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Discussion Starter #8
Hunter,

I have a KW BC20 and they are spec-ed for a 96V pack. The booster
only gets you up to 108V. I don't see how it will adequately charge a
144V pack at all.

There are other issues with this charger, mostly that *you* have to
figure out how long to charge, not the charger. To do this properly
you need an e-meter that measures the energy that you've used, and
then charge it back up to 105% of that (that number is from memory,
someone correct me it that's wrong.)

Or you can *guess* how long to charge it. This is what I did, being a
newbie that did not listen to others on the list, and it's a mistake
to do this (both ignore the list and also the guessing!) I have been
undercharging all along, and now my batteries have lost capacity that
cannot be brought back because they've sulfated. They aren't toast,
and I can get to work OK, but I have problems with that last hill
coming home - lost some range and shortened the life of the batteries.

I would advise a new charger for both these reasons. I am likely
going to get one myself before too long. The Zivan for example is
cheaper than the really good ones mentioned already, and while it has
a rep for overcharging the sealed batteries - with floodies you can
add water more often than you might otherwise. It is programmed at
the factory or dealer for your pack voltage and type.

Another thing mentioned was regulators for floodies. I don't have
them - wish I did. There's no off the shelf regs for floodies that I
know of. But what I do instead is monitor the batteries (using the
PakTrakr) and separately charge the ones getting weak with a 6V Soneil
charger I got for maybe $40. This has kept my pack from dying
*really* young instead of like, middle-aged :)

Enjoy the grin!!!! De

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Discussion Starter #9
If you have a E-meter and if you remove about 50 ah, then replace about 55
ah or that is about 10% more than you took out.

If you can check the specific gravity of the batteries, than when they are
all up to 1.275 sg, this is about 100 percent charge. If you E meter is
still reading any ah then 0.00, then reset it to 0.00 ah and this will be
very close.

Any time you are going to work on any voltage system that is go to disrupt
the E-meter, then its best to charge the battery to 100 percent or 1.275 sg
and reset the E-meter to zero. Then you can kill the EV power and when
restore the AH reading will be at 0.00 ah.

Roland


----- Original Message -----
From: "Deanne Mott" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Saturday, September 29, 2007 9:43 AM
Subject: Re: [EVDL] I have an EV!!!! (And some questions)


> Hunter,
>
> I have a KW BC20 and they are spec-ed for a 96V pack. The booster
> only gets you up to 108V. I don't see how it will adequately charge a
> 144V pack at all.
>
> There are other issues with this charger, mostly that *you* have to
> figure out how long to charge, not the charger. To do this properly
> you need an e-meter that measures the energy that you've used, and
> then charge it back up to 105% of that (that number is from memory,
> someone correct me it that's wrong.)
>
> Or you can *guess* how long to charge it. This is what I did, being a
> newbie that did not listen to others on the list, and it's a mistake
> to do this (both ignore the list and also the guessing!) I have been
> undercharging all along, and now my batteries have lost capacity that
> cannot be brought back because they've sulfated. They aren't toast,
> and I can get to work OK, but I have problems with that last hill
> coming home - lost some range and shortened the life of the batteries.
>
> I would advise a new charger for both these reasons. I am likely
> going to get one myself before too long. The Zivan for example is
> cheaper than the really good ones mentioned already, and while it has
> a rep for overcharging the sealed batteries - with floodies you can
> add water more often than you might otherwise. It is programmed at
> the factory or dealer for your pack voltage and type.
>
> Another thing mentioned was regulators for floodies. I don't have
> them - wish I did. There's no off the shelf regs for floodies that I
> know of. But what I do instead is monitor the batteries (using the
> PakTrakr) and separately charge the ones getting weak with a 6V Soneil
> charger I got for maybe $40. This has kept my pack from dying
> *really* young instead of like, middle-aged :)
>
> Enjoy the grin!!!! De
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

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Discussion Starter #10
Hunter Cook wrote:

> Sweet! My truck came in this afternoon! Drove around the
> neighborhood a
> bit and got my first EV grin. Good times.

EVs are addicting, aren't they?

> It's an '84 Chevy S10 w/ curtis 1231, adc 9", 22 nearly dead US-145 6v
> batts (the other two from the original 144v pack are totally dead),
> and
> a K&W BC20 charger.
>
> Those last two items bring me to my big question. A quick google of
> that
> charger number gets me a pdf that suggests to me that this charger is
> only meant for packs up to 108 volts, or 120 volts with a seperate
> buck/boost unit. Am I missing something here, or is this charger
> totally
> inadequate for this pack? Could this be why the batteries are just
> about
> toast now after 7500 EV miles (according to original owner)?
>
> Also, when I drove around briefly this afternoon, I noticed that if I
> pushed the throttle to hard (not to say gave it too much gas...) the
> volts guage would bottom out and the rear end would shake and bang a
> bunch. This seemed bad, and as I drove around it happened at less and
> less throttle. Is this just an artifact of a bad pack that can't draw
> many amps any more? Or something else? Any insight you guys have would
> be good.
>
> This was a good decision. I need batteries, a 12v battery (no
> headlights
> while accellerating ;-) and a power brake kit, and maybe a better
> charger, and my grin will be even bigger.

Oh, I don't recommend practicing the shudder! Its sure to be hard on
the drive train and not very good for the controller or main
contactor either. You have the reason right. A bad pack that sags
horribly under modest load and has little capacity (range) left.

You mentioned bad voltage sag and no 12v system battery. Likely what
is happening is that the DC to DC converter input voltage gets to low
and it cuts out. That opens the main contactor and cuts motor power.
Cutting the power causes the pack voltage to jump back up and the DC
to DC starts working again. The main contactor pulls back in and
power is suddenly applied. Repeat until you let up on the throttle
enough. Its likely a precharge system keeps the Curtis logic alive
(or you have an Curtis with "03" for the last 2 digits of the part
number - no high pedal start disable.)

I have no advice on the charger as I have never owned a K&W.

Paul Gooch

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Discussion Starter #11
Richard Acuti wrote:
> The Curtis has a maximum and minimum operating voltage. You are probably
> dragging the pack below the minimum usable voltage and the controller is
> cutting back your amps to keep the pack up at the minimum voltage, hence
> the shake, rattle 'n roll.

Ah, so *that's* what that was!

One day this spring, on one of my first test drives, I experienced the same
symptoms in the Curtis equipped ForkenSwift going up a slight incline - it
started bucking and lurching and losing speed. So I pulled over and waited
a few minutes, then tried again, sloooowwwwly creeping along the road...
followed by more bucking & lurching. Rinse & repeat a few more times, and I
eventually made it the half block to the driveway.

At that time the car had a wildly out of balance 36v test pack made up of
donated, used floodies from the company that sold us the donor forklift.

Shortly afterwards, I discovered what "cell reversal" means. :) Had to
look it up. Not surprisingly (to those who know better), I had done in one
of the geriatric batteries... my first incident of battricide.

It's fun being an EV noob on the learning curve. When the learning's not
too expensive.

Darin
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Discussion Starter #12
Maybe a good solution would be to get a lee hart battery balancer. It
takes some time with 24 batteries, but it can charge the pack through
the balancer so it can finish off what the other charger cannot. When
you do get a better charger you will still have a good balancer.

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Discussion Starter #13
David-

Thanks a ton for all this information on the charger. The only thing I'm
confused about is this: if this charger can't do a 144v pack (and I
certainly trust you on that) how could it bring my pack up from the low
120's up to 145v Saturday morning? Is that because a 108v pack would
have a finishing voltage up that high?

Not that the answer to that question really matters, I guess; clearly, I
need a new charger. I wasn't trying to be unrealistic on the
"inexpensive" requirement...I understand they are a bit pricey by
nature. But $1500+ vs. $700 or so for a Russco is a big difference to
me. Don't get me wrong, I can totally see how cool a PFC would be. Still
thinking about it...

Anyway, thanks again for the diagnosis.

Hunter



David Roden wrote:
> The BC-20 doesn't shut off, it runs forever. It has some current and
> voltage regulation, but not anything that you'd really call charge control.
> Its GFI also trips when the batteries get a little dirty and/or damp - and
> if you bypass the GFI to stop that nuisance, you have a potentailly
> hazardous condition because it doesn't provide isolation from the mains.
>
> AFAIK, it's not suited to batteries over 120 volts. I've used one at 128
> volts, but that's about as far as I'd push it.
>
> I'd like to tell you where to find a smart charger that will baby your
> batteries and give you the best possible range and costs $100, but there's
> no such animal. If you can't even pop for a PFC, which is pretty cheap for
> the amount of grunt it has, then you're probably best off to do what you can
> with the BC-20. That probably means dropping your pack voltage down to 120
> or 108 volts.
>
> If you're not going to use a smart charger, don't get VRR batteries, stick
> with flooded batteries. And, again, if cost is a primary consideration,
> flooded golf car batteries are the cheapest option. VRRs can easily cost 5-
> 10 times as much per mile of life.
>
> Enjoy your EV grin!
>
> David Roden - Akron, Ohio, USA
> EVDL Administrator
>
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Discussion Starter #14
Thanks Roland! This is fantastic information on my batteries; I
definitely didn't have a clue. I've got some comments/questions inline:

> The minimum discharge for these batteries are about 5.5 V per battery or 5.5
> V x 24 = 132 volts. So your existing battery charger cannot not even charge
> at the minimums.

I've got the same question for you that I posed to Dave...how did that
charger take me from 120 to 145v yesterday?
>
> Your battery volt gage should be red line at about 132 volts, where you
> should never go below that voltage. Its best to never take them below 144
> volts.

Do you mean "never deplete the pack to where it shows less than 132
under no throttle" or "never accelerate hard enough for your volts guage
to dip under 132" ? When I accelerate the volts guage dips *way* down,
like 10-20v. Of course, my pack's bad and I'm undercharging it. Somehow
I'm strangely comfortable with these facts...

>
> A good motor design for a EV, is where the name plate voltage of the motor
> would be at the minimum low limit of the batteries which would be at 132
> volts for a 144 volt pack. Normally motors have a service factor of 1.15 to
> 1.5 SF where they can take a over voltage.
Hrm. Well, it's an ADC 9" series wound. I didn't know any of the above,
but it's the same pack voltage and motor as a whole ton of EV's at
austinev.com, so I figured it was all good. Still, thanks for the info.

> As for the battery charger, I like to use a charger that can charge any
> battery voltage from a 12 volt battery to over 400 volts. Use any AC input
> voltage from 60 to 250 VAC at any ampere from 0.001 to 55 amps. Has
> multiple programs for any type of charger level and have input controls for
> equalization regulators or Battery Management Systems (BMS). I do not use
> BMS for my batteries yet, because after 6 years, the batteries are all in
> with 0.02 volts of each other on my T-145's batteries.
>
> This type of charger which is a Power Factor Control type (PFC) can be seen
> at: http://www.manzanitamicro.com

Boy those things are cool. Darn expensive, but cool. Do you know if the
Russco's and/or Zivan's can do the "equalization charge" you were
talking about?
>
> You normally will use a E-meter with this charger. My EV came with a
> separate bank of AC input and DC output meters in a separate rack panel and
> another set on the dash. Using a set of AC input meters, you can see the
> percentage difference between the AC input and DC outputs. If you charge at
> 50 amps DC you can actually be on a good magnetic 50 amp circuit breaker,
> where the AC amperes may be at 45 amps which is a 90 percent power factor.

Hehe. I've got an analogue voltmeter, ammeter, speedometer, and
odometer. There's a tach control installed, and I have the guage in a
bag, but the previous owner never got around to installing it, and
obviously I've been way too busy abusing the batteries. Maybe I should
get an E-meter.

I really appreciate you breaking it all down for me. You really filled
in all the missing numbers in my understanding of batteries. Thanks a
lot.

Hunter

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Discussion Starter #15
> > The minimum discharge for these batteries are about 5.5 V per battery or 5.5
> > V x 24 = 132 volts. So your existing battery charger cannot not even charge
> > at the minimums.
>
> I've got the same question for you that I posed to Dave...how did that
> charger take me from 120 to 145v yesterday?

A 12V battery is charged to roughly 14.4V for float charge, depending
on the batteries. So a 120V battery pack has a float charge of 144V,
which is where you ended up at after 8 hours. Your 144 volt pack
should go to roughly 172V on a full charge, though, so they're being
undercharged.

When he said your charger can't even do the minimums, he might have
thought 120V referred to the peak voltage instead of nominal voltage.

> >
> > Your battery volt gage should be red line at about 132 volts, where you
> > should never go below that voltage. Its best to never take them below 144
> > volts.
>
> Do you mean "never deplete the pack to where it shows less than 132
> under no throttle" or "never accelerate hard enough for your volts guage
> to dip under 132" ? When I accelerate the volts guage dips *way* down,
> like 10-20v. Of course, my pack's bad and I'm undercharging it. Somehow
> I'm strangely comfortable with these facts...

The no-throttle voltage should never go below 132. Under lots of
acceleration, the voltage may dip down, but that's mainly because of
the internal resistance of the batteries and cable; it isn't good, but
it isn't as bad for your batteries as using them while the no-throttle
voltage is low.

-Morgan LaMoore

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Discussion Starter #16
Thanks Richard!

Comments inline:

Richard Acuti wrote:
> Hi Hunter,
>
> And congrats. It's a good thing those batteries are already toast. You'd be putting a major hurting on them driving that way.
HAHAHAHAHA! Yep, I reckon I'm really beating the heck out of them, huh?
That was pretty much exactly what I was thinking when the tranny started
slamming from no volts: "dang, good thing these things are already
dead!"

More seriously, I am actually kind of glad that my first EV came with a
pretty dead pack. After reading so many stories of folks killing their
first pack (or part of it), and now especially after I find out I'm
chronically undercharging, it gives me some time to ease into the
battery handling game without quite so much risk. I don't think I'd have
quite such a devil-may-care attitude toward my mistakes if it had a good
pack. And of course, the vehicle was much cheaper ;-)

>
> The Curtis has a maximum and minimum operating voltage. You are probably dragging the pack below the minimum usable voltage and the controller is cutting back your amps to keep the pack up at the minimum voltage, hence the shake, rattle 'n roll.

That all sounds right to me. The voltmeter is definitely pegged at zero
when it happens.

>
> Re: Your charger- There was just a long thread on these but I didn't follow it. Check the archives. If the charger proves inadequate, someone may be able to direct you to a 2-charger solution, or if you have more money available you might look at a PFC or a Zivan charger. Russco also makes affordable chargers that will be properly matched to your pack.

Thanks. I think I'm probably looking at a Russco 18-120 with the
buck/boost. But that PFC sure is tempting. I still need to convince
myself (read: make up some ridiculous excuse. Something like "oh, I'll
totally need that when I want to build a huge dump-charger in my
garage!") that it's worth the extra dollars.

>
> When you get your new pack and charger situation worked out, don't pound the throttle. With new batteries after charging, your finishing voltage should be -about- 173 volts. (about 2.4 volts per cell, so 7.2 volts per battery) Your voltage at 80% depth of discharge should be -about- 138 volts.
>
> So that means-
>
> When driving, try very hard not to draw your pack below 138 volts while accelerating, and try not to finish driving below 138 volts.

Hmmm. So, in other words, my voltage should not be dropping much under
accel? Even when I don't have the slamming tranny and no radio problems,
when I give it much juice it definitely falls into the 10-20v range. Of
course, that's with a standing (no throttle) voltage of 140-145v.
>
> 138 volts works out to 1.91 volts per cell (each batt having 3 cells obviously). You really don't want to pull much lower than that because if you have any cells out of balance, you risk a cell or battery reversal (going below 0 volts, into negative territory). You'll ruin the battery very quickly.

I see. How do I know when I've reversed one?
>
> I have a 128 volt pack of 8v batts. Charging finish is 155. For me, the math works out to not go below 115-112 volts. I never accelerate harder than that, and I've never had a finish-driving voltage lower than 128 volts. Even then, I've done it only like twice.

Well, I don't feel quite as bad about Friday's escapade I guess. I
forgot for a minute that we're all talking about my pack as though it
were 144v (which it originally was, and will be again hopefully soon),
but right now it's 22x6v=132v, because two batteries are totally dead
and have been removed from the pack. So I have pretty close values to
your setup and I only pulled it down to around 120v. Of course under
accel I was still beating them up pretty good, and of course 145v is
still not up to snuff on the charging. But at least I wasn't running
them down as bad as I was thinking.

Hmmm...do you think I should pull 2 more out of the pack, to bring it to
a more BC20-friendly voltage?

>
> If you knew all of this already, I apologize. If I have said anything incorrect, I hope someone KNOWLEGEABLE steps up and corrects me. ;-)

Nope, I didn't know hardly any of this. Thanks a lot for all the
information!

Hunter

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Discussion Starter #17
Deanne, thanks so much for the K&W-specific info. A couple
comments/questions inline:

Deanne Mott wrote:
> Hunter,
>
> I have a KW BC20 and they are spec-ed for a 96V pack. The booster
> only gets you up to 108V. I don't see how it will adequately charge a
> 144V pack at all.
>
> There are other issues with this charger, mostly that *you* have to
> figure out how long to charge, not the charger. To do this properly
> you need an e-meter that measures the energy that you've used, and
> then charge it back up to 105% of that (that number is from memory,
> someone correct me it that's wrong.)

Yeah, that's a real bummer. Looks like a new, fancier charger is at the
top of my list.

>
> Or you can *guess* how long to charge it. This is what I did, being a
> newbie that did not listen to others on the list, and it's a mistake
> to do this (both ignore the list and also the guessing!) I have been
> undercharging all along, and now my batteries have lost capacity that
> cannot be brought back because they've sulfated. They aren't toast,
> and I can get to work OK, but I have problems with that last hill
> coming home - lost some range and shortened the life of the batteries.

Yep, sure sound like a lot of rookies do a lot of violence to a lot of
batteries. Certainly I have. And at least for a while I expect the abuse
will continue. Nice to not have much to lose, battery-wise.

>
> I would advise a new charger for both these reasons. I am likely
> going to get one myself before too long. The Zivan for example is
> cheaper than the really good ones mentioned already, and while it has
> a rep for overcharging the sealed batteries - with floodies you can
> add water more often than you might otherwise. It is programmed at
> the factory or dealer for your pack voltage and type.
>
> Another thing mentioned was regulators for floodies. I don't have
> them - wish I did. There's no off the shelf regs for floodies that I
> know of. But what I do instead is monitor the batteries (using the
> PakTrakr) and separately charge the ones getting weak with a 6V Soneil
> charger I got for maybe $40. This has kept my pack from dying
> *really* young instead of like, middle-aged :)

Do you leave the weak ones wired into the pack when you charge them
seperately? How often do you have to do this?

>
> Enjoy the grin!!!! De

I sure will. Thanks for your help.

Hunter
>
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Discussion Starter #18
Thanks for the clarifications, Morgan. Some comments inline:

> A 12V battery is charged to roughly 14.4V for float charge, depending
> on the batteries. So a 120V battery pack has a float charge of 144V,
> which is where you ended up at after 8 hours. Your 144 volt pack
> should go to roughly 172V on a full charge, though, so they're being
> undercharged.

All right, that makes sense. My pack is currently 132 (2 batteries out
of the 144v pack have been removed due to deadness) so I'm getting a bit
closer to a proper charge, but still not enough. Do you think I should
pull 2 more out until I get the new charger?

> The no-throttle voltage should never go below 132. Under lots of
> acceleration, the voltage may dip down, but that's mainly because of
> the internal resistance of the batteries and cable; it isn't good, but
> it isn't as bad for your batteries as using them while the no-throttle
> voltage is low.

Ok, I follow. My pack is just in real bad shape, causing the big dips under accel.

Thanks again for helping me out.

Hunter

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Discussion Starter #20
One more thing, You did not mention how much battery ampere and motor ampere
you are pulling. A good EV indications will be a amp meter shunt between
the batteries and controller to read the battery ampere and another amp
meter shunt between the controller and the motor to read the motor amperes.

You may find while you pull about 200 motor ampere, the battery ampere is
about 50 amps. Could be about 3 to 1 or 4 to 1 ratio at the lower rpm's or
speeds between 1 and 30 mph. As the rpm increases, the motor amperes will
about match the battery amperes in some controllers.

It is very important to watch your motor amps, so that you do not go over
the rated continuous ampere rating of the motor for too long. It is normal
for the battery ampere to be about 30 to 50 amps for city driving and may go
above 100 amps at 50 to 60 mph.

When you get your new battery pack and the correct charger voltage, you
should try to hold the battery ampere under 100 amps, better yet at 50
amperes for the first 100 charge cycles. These type of batteries take about
a 100 charge cycles to bring them up to the full ampere-hour during this
break in period.

The T-145's will increase about another 16 AH during this break in period.
Do not charge a too high rate yet, where it could blow the off the pasted
plates. You only want the pasted plates to open up slowly which then gives
you more surface area.

One time I went to a battery lab, where these type of plates were in a clear
container. They was checking out different charging current from 10 amperes
all the way up to 200 amps using different type of plate grid patterns and
inner ties. You can see that some battery plates had the paste blow
completely off the upper third of the plates which was closet to the top tie
bars only after 100 charge cycles at 100 amps and apply load at 300 amps.

A good battery grid pattern was the one that had wide spacing on the top and
narrow grid patterns on the bottom with tie bars on the bottom to equalized
the current through out the plate. This type of plate stood up much better
and gave a more even wear pattern.

With my EV, I am not going anywhere fast for a long distance, so 100 cycles
took me about 4 years to complete while driving about 5 miles a day.

A E-meter will only show battery amperes. The first ten years of driving
this EV, I only had a only battery ampere meter and was all ways pulling 180
battery amps at 170 volts at 60 mph. I found latter when I install a motor
ampere meter, the motor was pulling 200 amps which was 25 amps over the
continuous motor amp rating. A field winding connection finally open up
after 25 of running.

Roland


----- Original Message -----
From: "Hunter Cook" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Sunday, September 30, 2007 7:48 PM
Subject: Re: [EVDL] I have an EV!!!! (And some questions)


> Thanks Richard!
>
> Comments inline:
>
>
Richard Acuti wrote:
> > Hi Hunter,
> >
> > And congrats. It's a good thing those batteries are already toast. You'd
> > be putting a major hurting on them driving that way.
> HAHAHAHAHA! Yep, I reckon I'm really beating the heck out of them, huh?
> That was pretty much exactly what I was thinking when the tranny started
> slamming from no volts: "dang, good thing these things are already
> dead!"
>
> More seriously, I am actually kind of glad that my first EV came with a
> pretty dead pack. After reading so many stories of folks killing their
> first pack (or part of it), and now especially after I find out I'm
> chronically undercharging, it gives me some time to ease into the
> battery handling game without quite so much risk. I don't think I'd have
> quite such a devil-may-care attitude toward my mistakes if it had a good
> pack. And of course, the vehicle was much cheaper ;-)
>
> >
> > The Curtis has a maximum and minimum operating voltage. You are probably
> > dragging the pack below the minimum usable voltage and the controller is
> > cutting back your amps to keep the pack up at the minimum voltage, hence
> > the shake, rattle 'n roll.
>
> That all sounds right to me. The voltmeter is definitely pegged at zero
> when it happens.
>
> >
> > Re: Your charger- There was just a long thread on these but I didn't
> > follow it. Check the archives. If the charger proves inadequate, someone
> > may be able to direct you to a 2-charger solution, or if you have more
> > money available you might look at a PFC or a Zivan charger. Russco also
> > makes affordable chargers that will be properly matched to your pack.
>
> Thanks. I think I'm probably looking at a Russco 18-120 with the
> buck/boost. But that PFC sure is tempting. I still need to convince
> myself (read: make up some ridiculous excuse. Something like "oh, I'll
> totally need that when I want to build a huge dump-charger in my
> garage!") that it's worth the extra dollars.
>
> >
> > When you get your new pack and charger situation worked out, don't pound
> > the throttle. With new batteries after charging, your finishing voltage
> > should be -about- 173 volts. (about 2.4 volts per cell, so 7.2 volts per
> > battery) Your voltage at 80% depth of discharge should be -about- 138
> > volts.
> >
> > So that means-
> >
> > When driving, try very hard not to draw your pack below 138 volts while
> > accelerating, and try not to finish driving below 138 volts.
>
> Hmmm. So, in other words, my voltage should not be dropping much under
> accel? Even when I don't have the slamming tranny and no radio problems,
> when I give it much juice it definitely falls into the 10-20v range. Of
> course, that's with a standing (no throttle) voltage of 140-145v.
> >
> > 138 volts works out to 1.91 volts per cell (each batt having 3 cells
> > obviously). You really don't want to pull much lower than that because
> > if you have any cells out of balance, you risk a cell or battery
> > reversal (going below 0 volts, into negative territory). You'll ruin the
> > battery very quickly.
>
> I see. How do I know when I've reversed one?
> >
> > I have a 128 volt pack of 8v batts. Charging finish is 155. For me, the
> > math works out to not go below 115-112 volts. I never accelerate harder
> > than that, and I've never had a finish-driving voltage lower than 128
> > volts. Even then, I've done it only like twice.
>
> Well, I don't feel quite as bad about Friday's escapade I guess. I
> forgot for a minute that we're all talking about my pack as though it
> were 144v (which it originally was, and will be again hopefully soon),
> but right now it's 22x6v=132v, because two batteries are totally dead
> and have been removed from the pack. So I have pretty close values to
> your setup and I only pulled it down to around 120v. Of course under
> accel I was still beating them up pretty good, and of course 145v is
> still not up to snuff on the charging. But at least I wasn't running
> them down as bad as I was thinking.
>
> Hmmm...do you think I should pull 2 more out of the pack, to bring it to
> a more BC20-friendly voltage?
>
> >
> > If you knew all of this already, I apologize. If I have said anything
> > incorrect, I hope someone KNOWLEGEABLE steps up and corrects me. ;-)
>
> Nope, I didn't know hardly any of this. Thanks a lot for all the
> information!
>
> Hunter
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

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