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harro
26th April 2013, 05:52 PM
I bought a new red top Optima for my td5 defender on Wed. and went to install it today.
Out of interestput my volt meter on it just before i was to put it in and suprise, suprise 11.7 volts.
I so rang the place where I purchased it and was told it was probably my volt meter. I politely let them know it WASN"T my volt meter.
So the salesman went and checked the other stock.
The ones he tested were between 12.2 and 12.4 volts:eek:.
So............. I took my battery back and was given another one (straight off the charger) It tested 12.8 but was 12.62 by the time I got home.

Questions; what voltage should Iexpect with a new Optima?
How old can a 'new' battery be? (bit of a how long is a piece of string Q but you know what I mean).
So.........do I have a problem or is this normal, I usually buy Century so am a bit lost with the Optima agm thing for a cranking battery.

Thanks,
Paul.

FenianEel
26th April 2013, 05:58 PM
Sounds like an old battery, not that uncommon.
If it's sat on the shelf for too long, and not rotated out, it can be a couple of years old by the time you get it. If it hasn't been charged or cycled, it'll be no good.

Love Optima for deep cycle stuff, but I'd go a Century for cranking.

Eevo
26th April 2013, 06:20 PM
but was 12.62 by the time I got home.


err, that sounds like normal

open circuit voltages, % and density
12.60 V 100% 1.265 g/cm3
12.35 V 75% 1.225 g/cm3
12.10 V 50% 1.190 g/cm3
11.95 V 25% 1.155 g/cm3
11.70 V 0% 1.120 g/cm3

harro
26th April 2013, 06:31 PM
err, that sounds like normal

open circuit voltages, % and density
12.60 V 100% 1.265 g/cm3
12.35 V 75% 1.225 g/cm3
12.10 V 50% 1.190 g/cm3
11.95 V 25% 1.155 g/cm3
11.70 V 0% 1.120 g/cm3


Thanks for that info.
I always thought 12.8 was fully charged for a flooded lead acid and even higher for an AGM.
So maybe no problem at all.

Cheers.
Paul.

Eevo
26th April 2013, 06:56 PM
Thanks for that info.
I always thought 12.8 was fully charged for a flooded lead acid and even higher for an AGM.
So maybe no problem at all.

Cheers.
Paul.

if its just come off a charger it might be 12.8 or higher due to surface charge.

Eevo
26th April 2013, 06:58 PM
Thanks for that info.
I always thought 12.8 was fully charged for a flooded lead acid and even higher for an AGM.


hmm, i could be wrong

http://optimabatteries.com.au/wp-content/uploads/2012/07/Group-D34-YellowTop.pdf

Open Circuit Voltage (Fully charged): 13.1 volts
and the red top are 12.8volts

and wiki says 12.6volts hmm who to believe

Slunnie
26th April 2013, 08:04 PM
Love Optima for deep cycle stuff, but I'd go a Century for cranking.

I think the big advantage of the Optima is realised 5, 6, 7 years down the track when they're still working like new. I also think that there are awesome Optimas and crap ones, depending on which one you happen to pick up off the shelf.

drivesafe
26th April 2013, 08:09 PM
Hi Eevo and Open Circuit voltages vary from one battery type and make to another, but as you posted, for a new battery, that is way too low and should be replaced under warranty.

Paul, I would be demanding a replacement or your money back.

No new battery off the shelf should have a voltage of less than 12.4v.

BTW, how much did you pay for it?

Eevo
26th April 2013, 08:28 PM
No new battery off the shelf should have a voltage of less than 12.4v.


do stores charge batteries in stores?
if a battery has been sitting for 2 months i can be a 12.4v

it would require a charge and nothing more. nothing actually wrong with it

drivesafe
26th April 2013, 09:26 PM
If they look after their SLOW turnover stoke, they will charge them periodically but in the case of an Optima, because they hold their charge for a very long time, to be at 11.7v, it would either be faulty or have been on the shelf for a couple of years.

harro
27th April 2013, 09:16 AM
Hi Eevo and Open Circuit voltages vary from one battery type and make to another, but as you posted, for a new battery, that is way too low and should be replaced under warranty.

Paul, I would be demanding a replacement or your money back.

No new battery off the shelf should have a voltage of less than 12.4v.

BTW, how much did you pay for it?

Thanks for some informed comments from all.
Battery was $280 inc. GST.
Century wasn't a lot cheaper so I thought I would give the Optima a try.
Replacement Optima has held 12.6v overnight so hopefully all is ok (now:angel:).

Cheers,
Paul.