Battery wont charge after winter

ClintThrust

Member
Joined
Feb 5, 2020
Posts
18
They are putting out 3 volts but not any real electricity because they cant even flicker the dome lights. Trickle charger won't charge em.

I wrapped them up in an electric blanket and left them charging, but nothing so far.

Think they'll live?
 
A trickle charger might take weeks to bring your battery back up. Your batteries may have been permanently damaged by allowing them to discharge in cold temperatures but I wouldn't base that on the results of a trickle charger. A typical 6A charger will take 33 hours to charge a 200Ah battery to full from empty.
 
Really should **never** let a lead battery drop below 11V unless during controlled testing, and then only a few minutes.

They've definitely been damaged, only proper load testing can tell how much.

I would just replace.
 
You could look for a date on the battery. Batteries usually last for 3-5 years, if it is 3+years old and dead it is most likely toast. If it is only 1 year or so old you can charge it and see if it will hold a charge.
 
It's 4 years old. Follow up question; it is a 6 cylinder cummins diesel, would it need 24 volts to start or could I just buy 1 battery?
 
Replace like with like, have you ever started it successfully?

Can't imagine owning a truck and not knowing that?

Get the owners' manual at least and read it…
 
It's 4 years old. Follow up question; it is a 6 cylinder cummins diesel, would it need 24 volts to start or could I just buy 1 battery?

The starter is 12 volt. The two 12v batteries are connected in parallel to double the available cranking amps.

You may get away with one battery in warm weather but you are likely to have trouble in cold weather and reduce the lifespan of the battery.

My 6 cylinder Cummins all have two or three group 31 batteries in parallel.

I just replaced a set at BatteriesPlus. I paid a bit over $125 each including tax and environmental fee. If you have a Rural King near you I would check them out. I have heard of them putting Group 31's on sale for well under $100each.

Good luck.
 
Yeah its started a bunch but I sure don't daily drive the darn thing.

I only ask because I know we've driven my friends gas bus on 1 car battery, but I don't know if diesels are different.

And I don't have enough money to buy 2 batteries.
 
The starter is 12 volt. The two 12v batteries are connected in parallel to double the available cranking amps.

You may get away with one battery in warm weather but you are likely to have trouble in cold weather and reduce the lifespan of the battery.

My 6 cylinder Cummins all have two or three group 31 batteries in parallel.

I just replaced a set at BatteriesPlus. I paid a bit over $125 each including tax and environmental fee. If you have a Rural King near you I would check them out. I have heard of them putting Group 31's on sale for well under $100each.

Good luck.

Thanks man I'll probably just get 1 for now I've just gotta move it once here.
 
After the winter i had to replace 1 of my main batteries for this very reason.
Lead acid and agm should never drop.below 50% damage will occur
 
UPDATE

so I trickle charged them overnight and wrapped em up in a blanket and gave em a little jump with my car this morning and they're holding 12 volts.

Im sure its pretty bad for them but I'll probably replace them after this move because they shouldn't have died in the first place i reckon.

Njss8mU.jpg
 
Do you have a battery disconnect?

Your ECM probably draws a bit of current when the bus is turned off. If you park it for long without disconnecting the batteries you can kill your batteries.

The rig that I just put batteries in had one battery fail and I removed it leaving two group 31's. They lasted for a week or two then died. Of course they never die someplace convenient.......
 
Ok I was wondering what might be killing them that makes sense.

It doesn't have a disconnect that'll be the next thing I put in for sure.
 
They are putting out 3 volts but not any real electricity because they cant even flicker the dome lights. Trickle charger won't charge em.

I wrapped them up in an electric blanket and left them charging, but nothing so far.

Think they'll live?
I know this sounds stupid, but these are common problems...3 volts is really low. Were you reading off of the battery posts or thru the cables?


Did you check the water and clean the connections before trying to charge?
 
You’ll burn up your starter - just buy new batteries and make sure your wires are solid. Don’t risk it
 
Ok I was wondering what might be killing them that makes sense.

It doesn't have a disconnect that'll be the next thing I put in for sure.

Mine is currently broken. Fortunately it failed in the ON position. Until I get around to replacing it I disconnect the battery cable when parking for extended periods of time.
 
Just bought a new 8d for 2K4S. Been running with 1 for about 4 years but resting volts was 10.4. $186 at Batteries + and we're at 12.8. Starts instantly.

It does get into the 20's here often.
 
The deadly combination is cold + low voltage. if you keep them full, they can get absurdly cold without damage. They won't work as well while cold of course, but they'll recover from it.

If your batteries are discharged, the freezing point climbs quickly and damage happens.

screen-shot-2014-03-23-at-11-21-06-pm.png
 
Letting a lead batt sit at anything but 100% Full will murder it even more quickly in hot ambients.

Time spent at all discharged should be a tiny fraction of 1% of its lifetime.
 
The deadly combination is cold + low voltage. if you keep them full, they can get absurdly cold without damage. They won't work as well while cold of course, but they'll recover from it.

If your batteries are discharged, the freezing point climbs quickly and damage happens.

screen-shot-2014-03-23-at-11-21-06-pm.png


What does the blue line and the numbers beside it represent? The freezing point of the battery electrolyte and the actual temp where it crosses the SOC lines?
 
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