Resting Voltage??????

[Dr. Slam 10+ year member]

So what's a good way to test if these battery's are good?

 

[Drummer65 10+ year member]

So what's a good way to test if these battery's are good?

Load test on something like a VAT-40.

 

[Buck 5,000+ posts]

No battery should rest lower than 12.5 really, for car audio use. I think a battery can be drained as low as ~11.5, depending.

 

[disturbed471985 5,000+ posts]

Guys In am not here to start a war or anything. I bought the batt from basscort and I don’t think he would knowingly send me a bad batt being he knew I was going to put it thru its paces before I was happy with it. It’s been on a 6amp charger all night and is charging up to 13.1-13.4 which means there is life still in her. Going to pull off in about 4-5 hours and let batt sit for a good day and if he drops to the low 12's I no longer want this batt at which point I would go get load tested just to have paperwork saying the batt has issues.

Basscort IN now way am I angry at you or anything bro I mean I told you about this issue and you gave me steps to try and have keep in contact with me during this whole thing so no worries man. If batt turns out to be with issues then you and me will get it taken care of.,

 

[disturbed471985 5,000+ posts]

Hell..put it in the car and go for about an hour drive, and charge that joker up, and dont stop..Get on the highway,even.That should make a big difference??

LOL I cant it does not have enough power to turn the motor over..

 

[Buck 5,000+ posts]

wat

Batteries shouldn't fall that quickly.

 

[disturbed471985 5,000+ posts]

^^^ yea well I mean in his post he says they rest above 12.7 but now says that it has not be charged in awhile so IDK what to believe. All I know is 11.7-11.6 is not going to cut it. Was about to buy a second one from him just yesterday morning but I will hold off till this gets figured out.

 

[madcad95 10+ year member]

Well good luck I got 1 from him the other day and its sitting under the hood of my truck right now I did have to throw it on a charger for 15 minutes drove it to work and its been fine but its only been a couple of days though so take it for what its worth.

 

[disturbed471985 5,000+ posts]

^^ thanks for the reply man. I just think there is some kinda issue cause no way a batt should drop a volt in a 24 hour period. But IDK we will see nonetheless Basscort is keeping in contact so I feel good about getting this taken care of no matter the outcome of the test. My older deka 9a31's still rest at 12.6v and they are prob 2-3 years old. So at this time its best for me to keep using the dekas cause they are in proper working order right now.

 

[disturbed471985 5,000+ posts]

do you have a constant current charger to put it on? what battery is it? normally, i like to see them come off the charger at over 13v

Yes the charger charges at 6amps till batt is full and then cuts down to a trickle charge of I wanna say 1a maybe 1.5amp. Just bought the charger yesterday, Its a sprinter 370. Right now with charger its over 13v but if I remove it then it starts to fall to mid 12's fast I have not let it go as far down as it looks like it can. Once i hit below 12.4 I said screw it lets charge it for a good 10hours and see.

 

[audiolife 5,000+ posts]

please only knowledgable people chime in because this was my old batt i sold to him and i know 100% it was good it just wasnt charged for a while. If anyone knows about deep cycle batteries then they know that they can be depleted all the way down to almost 4 volts on some batteries and be "deep cycled" back up by putting them on a trickle charge of 2-5 amps for 1-2 days.
i dont want some retard saying "oh its bad cuz it rest low" if they have no idea about deep cycling. no need to scare him hes already weary of me now probly lol

When a lead acid battery discharges it sulfates. When you recharge it it desulfates (all chemical). If you leave a battery rest too long discharged the lead sulfate can crystalize making part of the battery NOT charge. Pretty easy to tell if the battery was left under charged because it will crystalize where it was left discharged at. You can try to slow charge and discharge and recharge and or use a desulfating charger can help fix it.

http://www.batterystuff.com/tutorial_battery.html

 

[audiolife 5,000+ posts]

actually not true,sorry josh,anything 12 volts and over is usually fine.put it on the charger dennis for 24 hours and load test it or let it sit another day or two ,then check the voltage.if under 12 after all this or load test's under 12 then it could be bad.

Totally depends on how the battery was kept. I would not allow a battery to be stored under 12.6 after it was used. When I store it I would remove from the vehicle fully charge it up on an automatic charger leave it float for a few hours then remove from the charger. After 3 hours with nothing on it measure battery voltage again (if it is an agm cell it should be above 12.7) if not leave on float charge for 24 hours, then remeasure. If it reads above 12.7v measure it the next day to be sure it stays above 12.7. If it does then check weekly then monthly until ready to use. If you leave a battery discharged at 12.3 volts it can and will sulfate and can crystalize.

 

[Dr. Slam 10+ year member]

When a lead acid battery discharges it sulfates. When you recharge it it desulfates (all chemical). If you leave a battery rest too long discharged the lead sulfate can crystalize making part of the battery NOT charge. Pretty easy to tell if the battery was left under charged because it will crystalize where it was left discharged at. You can try to slow charge and discharge and recharge and or use a desulfating charger can help fix it.Battery Tutorial

So what is your honest opinion about the battery then? Is it worth using or is it garbage?

 

[Imtjnotu 5,000+ posts]

gotta be a dead cell or 2 in there bro...does autozone still load test batts for u?

 

[disturbed471985 5,000+ posts]

It better not have dead cells cause I will be pissed.. I want this taken care of I paid for a batt with a resting voltage of 12.7min not 11.6... I will not eat any cost in this.