Battery question

[heath7162]

Bought a new Century Marine Pro 470 last week to power my sounder but is not wired to charge off the motor. When I got it I checked it on a multi-meter and it showed 12.3 volts. I tossed it on my charger and it charged up to 12.8 volts which I thought was full charge. I used it today and both my multi-meter and voltage display on the sounder showed the charge at 12.3 volts yet it hadn't been used.

Is 12.3 volts a full charge for a battery? Do you think something might be wrong with it?

Cheers.

[dreemon]

I'd have it checked , I've got a ? not sure what brand it is now but it's 2-4 yrs old and still shows 12.7 engine batt, the house batt is worse, shows 12.3 and after sitting on the water a few hrs it drops to 12.0 or less, but it 's old as the hills, Cheers

[finga]

They'll always drop a little bit if you check the voltage straight off the charger and then check the voltage again in a day or so.
What sort of charger as it sounds a smidge low straight off the charger??

[heath7162]

Straight off the charger was 13 plus volts but after I turned on the bilge for a few seconds it dropped- i've been told that the battery will show a higher voltage until it 'settles'. the day after coming off the charger read 12.8 volts. 12.3 seems low to me. Might take it back so they can put it on one of the gadgets to tell me if it's buggered.

[Roughasguts]

Batterys usually have 2.2 volts per cell when fully charged so 13.2 volts would be a fully charged battery.

But as a found out 2 days ago me battery in the Paj would not start the car in the morning! but it had 13 volts and fully charged in ten minutes on the charger but would break down with the starter motor load on it.

Lucky super cheap had 75 bucks of a 13 plate truck battery got it for 98 bucks bargain.

Anyway what I'm thinking is your battery is stuffed take it back for a replacement.

Cheers.

[oldboot]

Most standard lead acid batteries will settle to somewhere a little above 12 volts, it varies a bit depending on a number of factors But 12.5 should be about it.

Now this new battery...has it done any thing appart from be charged a couple of time and run your sounder.

If it has been sitting on the shelf for a while it might be a little sleepy and need a bit of a wake up.

If it will fit and if it is suitable...stick it in your car for a week and then try again.

Or you could try loading it up with a spot light or something for a couple hours then give it a stiff charge.


And OH yeh definitely what sort charger are you using. and what is the capacity of the battery.


cheers

[BM]

Get it checked mate. A fully charged standard lead acid battery will hover around 12.6V as fully charged. It may be down in one cell.

[heath7162]

Thanks guys. I'm using a CTek charger. After easter I'll take it back to get tested.

[johncar]

Can you be sure that your voltmeter is accurate also.
You would need to check your meter on a known point of reference as a comparison or have it calibrated to be sure.
As others have said, your battery will drop a little compared to immediately after charging. That is normal and 0.5 volts seems OK to me.
My boat batteries are fairly new and fully charged after settling for about 24hrs measure about 12.9V. My car battery at about 2 years old is 12.6V
But it doesn't mean alot unless volt meters have been calibrated and mine hasn't been done for a couple of years.
So based on that reading my voltmeter is reading 0.3v too high as I would expect a healthy battery say 24hrs after charging to measure about 12.6V.


So long as it is performing well and holding it's charge iit should be OK.
If you take your battery back for testing it would be worth testing your meter while you are there assuming there test gear is also accurate. But at least you will have a point of reference.