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Discussion Starter · #1 ·
This time, I've asked around and I think the advice I
got was good. Based on my situation, I think I have
to go with the 10 x 12 V Optimas (or other AGM - see
below). Why?

1. I really need sealed no maintenance batteries
because 4 of them are mounted under the rear seat and
are very very difficult to get to if you need to add
water. Also, most of the balance of them are in a box
in the rear behind the back seat. Having flooded lead
in the passanger compartment is a recipe for disaster.
So, I need to go with something maintenance free and
no acid leaks.

2. My charging system is set-up for 12 V batts. If I
change back to 8 v, I have a lot of extra work and
cost on my hands. Also, the 8 V batts don't seem to
be that much less cost. And, there is the whole issue
with flooded batts (at least in my car).

3. I'm still thinking about the possibility of NiCD
BB600, but charging will be an issue, and for sure
I'll have to redo the cabling and much of the battery
boxs. Still it may be worth it for better cycle life.
I really need to think that one over before
committing to anything.

4. I was very surprised that no one recommended the 12
V Group 24 Daka (East Penn) AGM 80 AH batts. I
thought those were the very best batts one could buy -
at least according to the manufacturer. They are even
a little less expensive than Optimas and have a higher
nameplate rated capacity. In the real world, maybe
they are less. I don't know for sure, but I always
thought those were very good top quality batts for the
price. No one else seems to think so though.

5. Just one last time, what is the fundamantal
difference between the Optima D34s (yellow top) and
D34MS (blue top). I believe the warranty is higher on
the blue top. But, is it that they can't handle high
discharge or temperature? Remember, I only have a
Curtis 550 A controller. But, I am going to spend a
lot, so I want the best possible solution. I'd go for
longer life over higher performance though. Given
that, which one is better, or which one do people have
more experience with. As for temperature effects, it
gets down to around freezing here, low 30's in the
winter (it snows a few days every few years) and top
high temperature of around 100 F right about this time
of year. The car is left outside year round. In the
summer, it gets very hot inside the car (where the
batteries are). It does have vents (not forced air
though), but I do see the batteries stitting at temps
well over 120 F in the summer. Thoughts on that?
Could that be killing the batts?


Thanks again.

Steve



____________________________________________________________________________________
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Discussion Starter · #2 ·
Steve Powers wrote:

> 4. I was very surprised that no one recommended the 12
> V Group 24 Daka (East Penn) AGM 80 AH batts.

DEKA is known for the quality of their AGMs, but that doesn't mean their
AGMs are at the same level.

The DEKA (Seamate 8A24M, 79Ah C/20, 140min RC, 470CCA/660CA, 53lbs)
looks OK on paper, but the real test is whether or not it will stand up
to the high currents Evs routinely subject their batteries to. Concorde
makes high quality AGMs, for instance, but they have been shown not to
stand up well to the rigours of EV use. I don't recall hearing from
anyone on the list using DEKA AGMs with success (I believe one of the AK
guys, Mike W perhaps?, started with a set of the group 31s but
encountered some sort of difficulties with them and set them aside in
favour of a set of floodies after just a short time).

For what its worth, the DEKA 8A24M, despite being a larger, heavier
battery has lower cranking amp ratings than the D34[M] Optima:
470CCA/660Ca vs 750CCA/870CA which would make me question if the DEKA
will survive EV use as well.

The Optima (and Orbital) is proven in EV use and at the 1hr rate it
should deliver 94% of the capacity of the group 24 DEKA while weighing
nearly 19% less.

I know 10 Optimas will do what you require because I have 10 in my car
and have an 8mi (each way, but I charge at work) commute. I know that
at 50% DOD it is possible to get 1000-1500 cycles from a set of properly
cared for YTs in an EV. The DEKAs may hold up as well, or they may not,
I can't say.

> 5. Just one last time, what is the fundamantal
> difference between the Optima D34s (yellow top) and
> D34MS (blue top).

Colour of the lid, and the blue top marine version comes with both SAE
automotive posts and threaded studs, which provides a convenient means
of attaching individual chargers or regs or monitors, etc. independently
of the high-current traction wiring.

Cheers,

Roger.

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Discussion Starter · #3 ·
Steve,

In response to question number 5, I do not find those exact model
numbers on the web. Do you mean Optima D34 (yellow top) and Optima D34M
(blue top)? I think you put the s on the end because you are talking
about many batteries, not because the s is part of the model number.

The D34M Blue top can be found here:
http://www.optimabatteries.com/publish/optima/americas0/en/config/produc
t_info/marine/technical_specs.html
Blue Top Type: D34M / D31M
These batteries are dual purpose. They are designed for engine starting
and deep cycling applications and for use in boats with large accessory
loads.


The Blue Top 34M is for starting. Avoid this for deep cycle use.

The D34 Yellow top can be found here:

http://www.optimabatteries.com/publish/optima/americas0/en/config/produc
t_info/automotive/deep_cycle/technical_specs.html

The top of the chart says Dual Purpose (Starting & Deep Cycle)
Batteries.

The difference that I see from the chart is the post/terminal type. The
D34M is dual SAE & 5/16 stud and the D34 is dual SAE & GM.

I have a D34M from Costco in my travel trailer. It does not get a lot
of use, and we do not take a lot of power out of it so I can't say much
other than I am pleased.

For the high temperatures in the summer, can you leave the windows down
about 1 inch? It gets up to 115 degrees F here in the summer, and I
keep the windows cracked. The dust in the vehicle is annoying. My wife
keeps all windows shut in her minivan, and in the summer in the sun it
feels like the inside of an oven when you first get in. I have a red
top starting Optima in my gas powered truck, and in the hot weather was
upset to find the posts leaking moisture / acid with corrosion. That is
why I went to the Optimas, no corrosion. I think the high temperatures
under the hood lead to this issue.

Good luck.

Alan

-----Original Message-----
From: [email protected] [mailto:[email protected]] On
Behalf Of Steve Powers
Sent: Wednesday, August 22, 2007 4:06 AM
To: [email protected]
Subject: [EVDL] That was some good advise (on my batteries)

This time, I've asked around and I think the advice I
got was good. Based on my situation, I think I have
to go with the 10 x 12 V Optimas (or other AGM - see
below). Why?

1. I really need sealed no maintenance batteries
because 4 of them are mounted under the rear seat and
are very very difficult to get to if you need to add
water. Also, most of the balance of them are in a box
in the rear behind the back seat. Having flooded lead
in the passanger compartment is a recipe for disaster.
So, I need to go with something maintenance free and
no acid leaks.

2. My charging system is set-up for 12 V batts. If I
change back to 8 v, I have a lot of extra work and
cost on my hands. Also, the 8 V batts don't seem to
be that much less cost. And, there is the whole issue
with flooded batts (at least in my car).

3. I'm still thinking about the possibility of NiCD
BB600, but charging will be an issue, and for sure
I'll have to redo the cabling and much of the battery
boxs. Still it may be worth it for better cycle life.
I really need to think that one over before
committing to anything.

4. I was very surprised that no one recommended the 12
V Group 24 Daka (East Penn) AGM 80 AH batts. I
thought those were the very best batts one could buy -
at least according to the manufacturer. They are even
a little less expensive than Optimas and have a higher
nameplate rated capacity. In the real world, maybe
they are less. I don't know for sure, but I always
thought those were very good top quality batts for the
price. No one else seems to think so though.

5. Just one last time, what is the fundamantal
difference between the Optima D34s (yellow top) and
D34MS (blue top). I believe the warranty is higher on
the blue top. But, is it that they can't handle high
discharge or temperature? Remember, I only have a
Curtis 550 A controller. But, I am going to spend a
lot, so I want the best possible solution. I'd go for
longer life over higher performance though. Given
that, which one is better, or which one do people have
more experience with. As for temperature effects, it
gets down to around freezing here, low 30's in the
winter (it snows a few days every few years) and top
high temperature of around 100 F right about this time
of year. The car is left outside year round. In the
summer, it gets very hot inside the car (where the
batteries are). It does have vents (not forced air
though), but I do see the batteries stitting at temps
well over 120 F in the summer. Thoughts on that?
Could that be killing the batts?


Thanks again.

Steve



________________________________________________________________________
____________
Boardwalk for $500? In 2007? Ha! Play Monopoly Here and Now (it's
updated for today's economy) at Yahoo! Games.
http://get.games.yahoo.com/proddesc?gamekey=monopolyherenow

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev

_______________________________________________
For subscription options, see
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Discussion Starter · #4 ·
Alan Brinkman wrote:

> The difference that I see from the chart is the post/terminal
> type. The D34M is dual SAE & 5/16 stud and the D34 is dual
> SAE & GM.

Almost, but not quite: the D34 (YT) has SAE post only; the D34/78 is the
version with SAE and GM terminals.

> For the high temperatures in the summer,

I missed the the temp question in the original post; definitely
temperatures of 120F (49C) are detrimental to the battery. On the plus
side, you'll get a bit better capacity from them and if you had a
controller that could exploit it, there'd be a bit more power there too.

Optima specifies a maximum temperature of 125F (51.7C) during charge,
and if your batteries are heat-soaked at 120F before you start driving,
you'll probably exceed this. If at all possible, try to provide some
ventilation to keep the batteries nearer to ambient; perhaps one or two
of those little solar powered fans with the windows cracked open a bit
would be enough.

That said, the high temp probably won't reduce the life enough to matter
since EV usage is probably going to wear the batteries out in 2-4yrs
anyway. My concern would be that the batteries will be more prone to
thermal runaway at these high temps and you will need to ensure your
chargers are temperature compensated and can properly take care of the
batteries at these temperatures.

Cheers,

Roger.

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Discussion Starter · #5 ·
Alan Brinkman wrote:
Steve Powers wrote:
> Based on my situation, I think I have to go with the 10 x 12 V Optimas
> (or other AGM - see below). Why?
>
> 1. I really need sealed no maintenance batteries because 4 of them
> are mounted under the rear seat and are very very difficult to
> get to if you need to add water... Having flooded lead in the
> passanger compartment is a recipe for disaster.

These are good reasons to go with sealed batteries. But if you really
did want to go with floodeds (for cost or range etc.), you can install
automatic watering and venting on them. This can eliminate the problems
of access for watering and fumes in the passenger compartment.

Even with sealed batteries, you still need to design your battery boxes
to handle acid leaks and gassing. Sealed batteries still vent and leak
acid! Just a lot less. If you look at an old pack of AGMs, it is common
to see corrosion damage on at least some terminals.

> 2. My charging system is set-up for 12 V batts. If I change back to
> 8 v, I have a lot of extra work and cost on my hands.

Yes, unless your pack voltage works out the same, or the charger is
adjustable.

> Also, the 8 V batts don't seem to be that much less cost.

Depends on what you are comparing. An Optima certainly costs more than
an 8v flooded golf cart battery, and has a shorter life and less total
energy storage.

> 3. I'm still thinking about the possibility of NiCD
> BB600, but charging will be an issue, and for sure
> I'll have to redo the cabling and much of the battery
> boxs. Still it may be worth it for better cycle life.

And, they are flooded batteries. *Lots* of watering and gassing!

> 4. I was very surprised that no one recommended the 12 V Group 24
> Deka (East Penn) AGM 80 AH batts. I thought those were the very
> best batts one could buy

They are indeed very good batteries -- but not built for high currents.
You would have to be happy with your controller turned down to its
lowest current, to keep them below 200-300 amps max, or they would have
very short life.

> 5. As for temperature effects, it gets down to around freezing here,
> low 30's in the winter... and top high temperature around 100 F
> right about this time of year.

I would strongly advise building insulated boxes to put your batteries
in. 1" of styrafoam is plenty; even 1/2" will do if that's all you can
fit. Include a small heating pad and thermostat to hold them at about 70
deg.F in the winter. Without this, your range will *halve* in the
winter!

High temperatures increase battery capacity, but shorten life. If you
put them in insulated boxes as I suggest, include a fan that you can
turn on at night. The fan should circulate air from *outside* the car.
The insulation will make the batteries sit at the average day/night
temperature, which should be fine -- even if it is 120 deg.F in the
daytime, it will be 80 deg.F at night. The fan will remove any trapped
heat from charging and driving.

Plus, these boxes and the fan will handle any inadvertent gassing or
venting.
--
"Never doubt that the work of a small group of thoughtful, committed
citizens can change the world. Indeed, it's the only thing that ever
has!" -- Margaret Mead
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net

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Discussion Starter · #6 ·
On 22 Aug 2007 at 4:06, Steve Powers wrote:

> Having flooded lead
> in the passanger compartment is a recipe for disaster.

I wouldn't go THAT far. Many of us have done this for years. They just
have to be secured well and properly enclosed and ventilated, that's all.

> I was very surprised that no one recommended the 12v
> Group 24 Daka (East Penn) AGM 80 AH batts.

I don't think there's enough experience with them to say one way or the
other. However, Optimas have been widely used by EVDL members for many
years.

> I do see the batteries stitting at temps well over 120 F in the
> summer. Thoughts on that? Could that be killing the batts?

Yep.

David Roden - Akron, Ohio, USA
EVDL Administrator

= = = = = = = = = = = = = = = = = = = = = = = = = = = = =
EVDL Information: http://www.evdl.org/help/
= = = = = = = = = = = = = = = = = = = = = = = = = = = = =
Note: mail sent to "evpost" or "etpost" addresses will not
reach me. To send a private message, please obtain my
email address from the webpage http://www.evdl.org/help/ .
= = = = = = = = = = = = = = = = = = = = = = = = = = = = =


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Discussion Starter · #7 ·
I was thinking of adding a very small solar panel hooked up to a fan and a
temperature sensor on mine.

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf
Of David Roden
Sent: Friday, August 24, 2007 3:59 PM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] That was some good advise (on my batteries)

On 22 Aug 2007 at 4:06, Steve Powers wrote:

> Having flooded lead
> in the passanger compartment is a recipe for disaster.

I wouldn't go THAT far. Many of us have done this for years. They just
have to be secured well and properly enclosed and ventilated, that's all.

> I was very surprised that no one recommended the 12v
> Group 24 Daka (East Penn) AGM 80 AH batts.

I don't think there's enough experience with them to say one way or the
other. However, Optimas have been widely used by EVDL members for many
years.

> I do see the batteries stitting at temps well over 120 F in the
> summer. Thoughts on that? Could that be killing the batts?

Yep.

David Roden - Akron, Ohio, USA
EVDL Administrator

= = = = = = = = = = = = = = = = = = = = = = = = = = = = =
EVDL Information: http://www.evdl.org/help/
= = = = = = = = = = = = = = = = = = = = = = = = = = = = =
Note: mail sent to "evpost" or "etpost" addresses will not
reach me. To send a private message, please obtain my
email address from the webpage http://www.evdl.org/help/ .
= = = = = = = = = = = = = = = = = = = = = = = = = = = = =


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