My battery died a couple weeks ago and it tested at 10.5 volts. I understand that jump starting it and letting the alternator charge it up is detrimental to the alternator. Can someone confirm or deny this? Should I just take it to the store to get it properly charged or should I hook it up to another car for a jump start?
Středozápadní drifter
Inženýr v rezidenci
Just jump it an go. There is no appreciable risk. Maybe if the alternator was marginal, but then it needs replaced anyway.
You will want to put a good charger on the battery when possible, as getting it back to full by driving would take 12 hours or so.
john61ct
Aktivní člen
Your battery was damaged, as in losing some capacity and longevity.
Yes just from being allowed to drop so low
but much more so from being allowed to **sit** for any length of time at anything below Full, but especially that low.
In doing capacity testing down to 0% Soc, the rule is start recharging immediately.
Best to charge back to 100% Full, at least overnight. Alternator could take many days to get there, if not weeks depending how many hours per day you’re driving.
Just because it cranks, doesn’t mean it’s Full.
BrennWagon
Je to prostě ten chlap, víš?
If you can, charge it with a plug in battery charger. If it takes a charge and holds that charge for a day or so you should be ok but if it doesn’t it’s new battery time. Batteries can survive being drained beyond 10V but they shouldn’t do it often
My Sprinter’s A Lemon
Člen
It’s currently at 10.44 volts but the guy at the store says he can’t recharge it because «there is no charge», ergo. bad battery. He got a big red X to say it doesn’t have or hold a charge. Help me understand. Thanks.
I found this chart:
State of Charge Voltage
100% 12.7 — 13.2
75% 12.4 XNUMX
50% 12.2 XNUMX
25% 12.0 XNUMX
Discharged 0 — 11.9
So, at 10.44, we conclude it is «discharged», therefore can’t be recharged. Henceforthwith, when a battery typically dies, and it is successfully jump started, we would conclude that it is 12.0 or better? . just getting it straight in my mind. Thanks.
Poslední úprava: 7. října 2019
john61ct
Aktivní člen
Voltage does not in itself carry much meaning.
Lots of monitoring / control / charging circuitry will refuse to charge below a certain point.
But special gear designed to try to «resurrect» old / dead flat batteries can use a very gentle low rate over night or days.
Then if it «holds a charge» at say 11.5V or higher, can try to get it back to 100% Full with a regular charger.
But it has been damaged, often such a battery really should just be replaced with new.
Really bad ones can explode.
john61ct
Aktivní člen
Only a load / capacity test will tell you for sure.
For deep cycling batteries, 70-80% capacity is scrapping time.
Starter batteries CCA is the measure.
Středozápadní drifter
Inženýr v rezidenci
Some chargers won’t charge if they see a voltage below 11V. Though most look for at least 9V. It should still accept a charge usually. Just parallel it with another battery for the first couple minutes.
My Sprinter’s A Lemon
Člen
Some chargers won’t charge if they see a voltage below 11V. Though most look for at least 9V. It should still accept a charge usually. Just parallel it with another battery for the first couple minutes.
If I stick it back in the van and successfully jump start it, should I then take it out and have it fully charged at the store or would you reiterate your earlier comment that its okay to have the alternator charge it with no ill effects?
Středozápadní drifter
Inženýr v rezidenci
Just let the alternator charge it. Millions of folks jump their vehicles every year. There is no plague of failed alternators. Its a self limiting system, with the wiring, alternator, and battery acceptance rate all combining to prevent the often repeated urban myth of the «fried alternator».
autostaretx
Nevyzpytatelný člen
The battery can have warped plates in one cell (a 12v lead acid battery is six 2v cells in series).
Those warped plates can/will «short out» that cell, so any charger will see that it cannot bring the entire battery up to 12v.
You end up with a 10v battery (five cells) and (basically) a «chunk of wire» as the 6th cell.
The «easiest» way to end up with warped plates is to let the fluid levels drop well below the top of the plates . that forces the charging/discharging currents to use less surface area of the plates, which heats them up and they warp from the heat.
Fighting plate-warping/shorting is one of the features of AGM batteries . the Glass Mat lies between the plates and serves as a physical insolator.
Poslední úprava: 8. října 2019
Středozápadní drifter
Inženýr v rezidenci
Do put the battery on the charger as soon as convenient. This raises the odds the battery will recover enough to be useful.
Also note that corroded cables can play a big roll in battery decline, especially the battery and engine ground straps.
My Sprinter’s A Lemon
Člen
I charged the battery with jumper cables and got it from 10.5 to 12.4 in about 90 minutes. I took it to a different Canadian Tire and the guy said the battery is fine. He measured it at 12.8 and he said it is 90% charged. So my hunch was right. The first CT guy didn’t know what he was talking about
Thanks for the help everyone. My Lemon has one less problem.
My Sprinter’s A Lemon
Člen
UPDATE: it doesn’t seem to hold a charge; it keeps going down to 11.7 or so. Time for a new battery. I hope its a bad battery and there isn’t a drain on it that I don’t know about. I’m getting the T21 recall completed as soon as they get the parts.
Garandman
Aktivní člen
Is it an AGM battery? If so they won’t typically charge at that level of discharge.
Some smart chargers will fix it. But if you don’t have one (we use a Noco Genius) manufacturers publish a way to bring them back. If you hook another battery to it in parallel (+ to + and — to -) and put the charger on that, it will bring it back. While typical flooded batteries have slightly different voltages, I’ve used one when I didn’t have two AGM’s available.
Also done this with two different sizes, such as a snowmobile battery and car battery.
You can find the procedure many places, here’s one.
my car wouldn’t start so i turned everything off and meaured the battery voltage . it was 10V. Do you think i should re-charge it , or does 10V mean its ruined forever ?
joozwa
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Lead acid battery = 10V
«Store always at a full state-of-charge. Do not store below 2.10V/cell; apply topping charge very 6 months.»
Vzáno z:
**nefunkční odkaz odstraněn**
I think it explains everything.
Pozdravy
Audioguru
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Joined Jan 19, 2008 Messages 9,450 Helped 2,151 Reputation 4,302 Reaction score 2,004 Trophy points 1,393 Location Toronto area of Canada Activity points 59,660
Lead acid battery = 10V
Is your car battery more than 5 years old?
Does your car turn off everything if you forget?
eem2am
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Re: Lead acid battery = 10V
yes, everything was turned off.
i can’t understand how its so flat, i drove it fine 4 days ago. then 2 days ago i got in and it seemed completely flat.
there was a bit of cold weather in uk of late but not that cold
FvM
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Lead acid battery = 10V
An old battery may spontaneously fail. You’ll find out the actual battery condition, after you tried to recharge it. With an old one, it may be waste of time.
eem2am
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Lead acid battery = 10V
hello, i re-charged it with a cheap charger.
the charger was 2.7 Amps DC.
The battery became fully charged (or rather the green «fully charged» LED came ON) after 7 hours.
When fully charged , its voltage open cct is now ~12.6V
That doesnt seem long for a 200Ah battery
(Battery is «Fiamm L1 200»)
Do you think its ruined ?
I’m wondering about driving anywhere in it in case it dies when i’m at the destination
Ante
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Re: Lead acid battery = 10V
If possible measure the specific gravity of the electrolyte in all cells, should be about the same in all cells (1.27 – 1.28). Check if you have any current “leaks” by disconnecting the negative wire from the battery (everything shut off in the vehicle) and connect a bulb between the wire and the battery, if the bulb comes on you have a consumer which drains your battery. The voltage (12.6) seems ok so you should be able to start you car again. 200Ah is a very large battery for a car, more like a truck size battery. “Normal” cars usually have from 60 to 110 Ah (90 and up for diesels).
xaccto
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Re: Lead acid battery = 10V
measure the voltage when you apply a load, Eg Engine not running, turn on all your head lights, now measure the voltage, if it immediately drops to 10V or less, one
or more of the cells in the battery is DEAD.
A very good battery, though a bit discharged should crank a vehicle whilst its terminal voltage drops to 10volts.
200ah is indeed a very very very big battery for a car though.
mister_rf
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Re: Lead acid battery = 10V
eem2am said:
When fully charged , its voltage open cct is now ~12.6V
In my opinion there’s still one element in short-circuit.
Usually you may have 2.4V per element at full charge, that’s a total of 14.4V for a 6 elements pack.
pranam77
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Re: Lead acid battery = 10V
Hai friend. You try these remedies and tests. First measure the specific gravity of the acid. Be sure you have enough electrolyte with good gravity. Try charging the battery with the charger having atleast 10% of the total battery capacity in Ampheres. Connect a 10 amp ammeter in sieres to the posetive line and see wether it drops to «zero» indicating full charge. If it doesn’t, do that within 12-16 hours, your battery is GONE. If it does come to «Zero» well your battery passed first test. A fully charged 12 volts battery should measure 13.2v to 13.8v with fully charged condition. Secondly after getting full charged, try to crank the engine. If it does, for consecutive 4-5 attempts, the battrey is 90% ok. If it doesnt crank more than 1-2 times, then i strongly recommend to replace it.
