Is this lead acid battery bad? Or am I bringing it back to life?

Thread Starter

Teljkon

Joined Jan 24, 2019
265
Hello,

My car battery seems to be on the fritz. I had it on the trickle charge most of last night and it was showing about 11v at the posts when the sun went down. Today how ever the battery seems to be showing about 10v of charge at the posts. Is this bleed in voltage a sign that the battery is not holding a charge and I need a new one? Or is the trickle charger breaking up a crystallization and is the battery showing new life? It is not currently connected to the car in any way as a far as I know.

Also I have one of those alternator check devices I could use but at this stage I think it is unrelated and the problem lies in the battery alone. Thanks In advance. For the borrowing of you knowledge and expertise. Also this is not a homework question.

Correction 10.5 volts and this could be a rounding error because I had the multi meter on a different setting.
 
Last edited:

Dodgydave

Joined Jun 22, 2012
10,230
You need to measure the battery under load, charge the battery up normally on full not trickle, then put a load on it like a bulb or headlamp and note the voltage.
 

crutschow

Joined Mar 14, 2008
29,466
10 or 11V is a fully discharged battery unless there is a shorted cell.
Fully charged, it should be about 12.6V after a 12 hour rest.

How old is the battery?
Generally they are only good for 3 or 4 years.
 

Thread Starter

Teljkon

Joined Jan 24, 2019
265
10 or 11V is a fully discharged battery unless there is a shorted cell.
Fully charged, it should be about 12.6V after a 12 hour rest.

How old is the battery?
Generally they are only good for 3 or 4 years.

Thanks that answers allot right there. Since before this I was getting a charge of 9v and lower it is probably done for then. Since it is definetly more than three years old I will probably replace. However if it is not completly trash I have another project I may use this for just to experiment and learn.
 

dl324

Joined Mar 30, 2015
14,302
Also I have one of those alternator check devices I could use but at this stage I think it is unrelated and the problem lies in the battery alone.
Weak batteries can kill alternators.

If you can't charge the battery to 12.5-12.6V, it's bad. You could try using a battery maintainer that tries to remove sulfation. I had a 3 year old battery that would no longer hold a charge. I used a battery maintainer on it and now it's holding charge to start the engine for over a month. It took a couple days for the maintainer to get to full charge and switch to maintain mode.
 

Thread Starter

Teljkon

Joined Jan 24, 2019
265
You need to measure the battery under load, charge the battery up normally on full not trickle, then put a load on it like a bulb or headlamp and note the voltage.
Sure Will do I have to make a run around town and since this is my primary car I am going to do that. I will then test it when I return and give you the results.
 

dl324

Joined Mar 30, 2015
14,302
However if it is not completly trash I have another project I may use this for just to experiment and learn.
Try a battery maintainer. I had a riding lawnmower battery that wouldn't hold charge and I had to jump start it every week. I replaced the battery, but kept the old one and tried using a battery maintainer on it. It's holding charge for longer than a month, but I haven't put any heavy loads on it.

Since the battery is in your primary vehicle, you should get a Li-ion jump starter to carry for peace of mind.
 

Thread Starter

Teljkon

Joined Jan 24, 2019
265
Weak batteries can kill alternators.

If you can't charge the battery to 12.5-12.6V, it's bad. You could try using a battery maintainer that tries to remove sulfation. I had a 3 year old battery that would no longer hold a charge. I used a battery maintainer on it and now it's holding charge to start the engine for over a month. It took a couple days for the maintainer to get to full charge and switch to maintain mode.
I will keep that in mind thank you. Your kind of confirming what I already figured out it had a drop in voltage from sitting for to long and after jumping it once I failed to use it again in a timely manner. Basically its starting to suffer from some kind of internal sulfation. I have now had it on a charger for the better part of a day now and it keeps holding a slightly higher charge each time. So I am probably bringing it back but for the strain on the alternator and the cost of new battery. I will probably just replace it. Like I said thought I would like to see if I can revive it for a learning project.
 

sparky 1

Joined Nov 3, 2018
701
In the morning the homeless guy's batteries are up a few volts so I lugged it into the autoparts store to let them test it.
The parts guy said the date was expired but he would put it on the charger and to come back in a couple hours.
I browsed the store looking for a better way to lock the hood because the number of night creatures is growing.
When he tested it he showed me it was dead and far gone. If he had said it was sort of hurting then should I continue with uncertainty
for my situation I wanted more dependability in being able to move the car on street sweeper day.
 
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Thread Starter

Teljkon

Joined Jan 24, 2019
265
In the morning the homeless guy's batteries are up a few volts so I lugged it into the autoparts store to let them test it.
The parts guy said the date was expired but he would put it on the charger and to come back in a couple hours.
I browsed the store looking for a better way to lock the hood because the number of night creatures is growing.
When he tested it he showed me it was dead and far gone. If he had said it was sort of hurting then should I continue with uncertainty
for my situation I wanted more dependability in being able to move the car on street sweeper day.
you know the quote feature can also be used to quote books and novels and such.
Ahuramazda said:
Despite being a bad king his foot was sent to spend eternal bliss with god for the compassion it showed the goat when kicking that ball of hey
The bible said:
In the beginning there was darkness and then god spoke "let there be light".
D&D said:
Roll 6D6 to get your stats or use the standard array provided below
 

dl324

Joined Mar 30, 2015
14,302
I have now had it on a charger for the better part of a day now and it keeps holding a slightly higher charge each time.
A normal charger won't remove sulfation. A maintainer with a restore option will use high frequency, higher voltage pulses to try to remove sulfation. The one I have gives up after an hour. It did that several times on my lawnmower battery. I alternated between the regular charger and the maintainer and the maintainer was finally able to restore some capacity to the battery.

Does your battery have any warranty left? My mower battery was long out of warranty (it's only 90 days). Warranties on car batteries have gone down lately. I think I could only get 48 months for the last one I bought. It's on a vehicle that doesn't get used often, so now I keep a maintainer on it.
 

Thread Starter

Teljkon

Joined Jan 24, 2019
265
A normal charger won't remove sulfation. A maintainer with a restore option will use high frequency, higher voltage pulses to try to remove sulfation. The one I have gives up after an hour. It did that several times on my lawnmower battery. I alternated between the regular charger and the maintainer and the maintainer was finally able to restore some capacity to the battery.

Does your battery have any warranty left? My mower battery was long out of warranty (it's only 90 days). Warranties on car batteries have gone down lately. I think I could only get 48 months for the last one I bought. It's on a vehicle that doesn't get used often, so now I keep a maintainer on it.
TDIL. Yeah I put the multi meter on it today after few hours on the trickle charger. An watched it drop from 12.3v to 11.5v in seconds. Tried to give it a start an click click click. I just bought a new one. I will probably buy a marine battery for said project i wanted to renew that old Lead Acid battery for. I thank everyone for there help it was all educational no matter how elementary it was for you guys. Thanks again. I am still looking at a maintainer though thanks thrice for that tip.
 

Tonyr1084

Joined Sep 24, 2015
6,861
if it is not completly trash I have another project I may use this for just to experiment and learn.
Car batteries have wet cells, acid. That acid can get on things you didn't think it would and cause corrosion. Including clothing and flesh. Be careful when messing with an old car battery. I've ruined a few pairs of jeans messing with batteries. And I didn't even know it, but one time I got a very tiny drop of acid on the back of my hand. Still have a tiny scar from that incident. And simply washing my hands didn't remove the acid. Baking soda will neutralize the acid. But in general, old car batteries are not worth the hassle.

I got one of those battery maintainers to try and recover an SLA battery (Sealed Lead Acid). That's where I got the burn from too. And in the end the battery was just trash. So I sent it for recycling.
 
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