How long to charge Dead Car Battery

In summary, the battery in this car was discharged to the point where it would not start. The jumper car was able to charge the battery sufficiently to get it running. It is recommended that if the battery is not going to be used for an extended period of time, it should be fully charged and kept at a warm temperature.
  • #36
How long do you expect to keep the car? If no more than a few years, I would just opt for a cheap battery with a 24 month warrenty.

BTW, congrats on the round number Russ. 23,000! :w
 
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  • #37
Borg said:
How long do you expect to keep the car? If no more than a few years, I would just opt for a cheap battery with a 24 month warrenty.
No less than 3 more years, probably more like 5 (it is less than 3 years old now: 50,000 miles). So if I replace it, it will be with a good battery.
BTW, congrats on the round number Russ. 23,000! :w
Thanks!
 
  • #38
russ_watters said:
it overnight, it decays to 11.3.
That has the ugly sound of one cell having an "adolescent identity crisis." I've never been able to straighten them out when they "rebel" and reverse polarity.
 
  • #39
My automotive electrican sez that you'll over work the alternator, you really should charge the battery.
 
  • #40
russ_watters said:
It got me to Harrisburg, so I'm good for now...

As they age they lose capacity. It's a gradual tapering .
I learned to tell by the sound of the starter when a battery was nearing end of life. It's more pronounced in a diesel with its twenty-something to one compression... if it drops below 9 volts while cranking it's weak.
Five years isn't too bad for a OEM battery.
Dont buy a cheap one is my advice. I've had two from "bargain" auto parts stores fail when inter-cell connectors inside cracked. One of them i tried to check cranking voltage and it exploded in my face, blew the top off and spattered acid everywhere. Good thing i was wearing glasses.. acid wrecked a pair of Dockers and a good shirt.
The neighbors came running over thinking somebody had got shot.
Moral: only check cranking voltage from cigarette lighter socket with hood closed.

About fifteen years ago Consumer Reports did one of their studies and concluded that over 3/4 of the batteries in US are made by Johnson Controls. They're sold under myriad brand names.
At the time that's where Wal-Mart got their batteries. CR recommended Walmart because they sell so many they're always fresh.

my two cents

old jim
 
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  • #41
ps i use the generic 6 amp charger. I prefer the heavy ones with a ferroresonant transformer, but they're getting hard to find.
My neighbors have not had good luck with the all electronic computerized-inverter ones.
http://www.tractorsupply.com/en/store/travellerreg;-2-6a-manual-battery-charger-101588799--1

http://media.tractorsupply.com/s7viewers/dhtml/images/spacer.gif
1015887?$prod_det$.jpg

http://media.tractorsupply.com/s7viewers/dhtml/images/spacer.gif
Get one at a yard sale and replace the wires. Sniff it for burnt transformer smell, though.

old jim
 
  • #42
jim hardy said:
...
Five years isn't too bad for a OEM battery...

my two cents

old jim

That reminds me. My brand new truck is now 6 years old, and hasn't been starting as fast as she used to. hmmmm...

12.46 VDC

Time for a new battery.

Although a value of 12.46 indicates my battery is at around 80% charge, it should be reading 100%, which is around 12.6 volts.
I destroyed my last deep cycle battery this winter, by ignoring it. I just checked it, and it's reading about 12.3 volts, which indicates that it's 50% charged.
But, my last test discharge, even after being fully charged, indicated it had pretty much zero capacity left.

@russ_watters , you never did tell us what kind of new battery you got. As I mentioned, I'm now in the market for a new one.

ps. This thread reminds me of my very first "helpy" post.
Danger seemed to approve.
Probably a bad sign.
 
<h2>1. How long does it take to charge a dead car battery?</h2><p>The time it takes to charge a dead car battery can vary depending on the type and size of the battery, as well as the charging method. On average, it can take anywhere from 4-24 hours to fully charge a dead car battery.</p><h2>2. Can I charge a dead car battery overnight?</h2><p>It is not recommended to charge a dead car battery overnight, as overcharging can damage the battery and potentially cause it to explode. It is best to monitor the charging process and disconnect the battery once it is fully charged.</p><h2>3. How do I know when my dead car battery is fully charged?</h2><p>Most modern car battery chargers have built-in indicators that show when the battery is fully charged. If your charger does not have this feature, you can use a voltmeter to measure the battery's voltage. A fully charged car battery should have a voltage of around 12.6 volts.</p><h2>4. Can I jumpstart a dead car battery instead of charging it?</h2><p>Jumpstarting a dead car battery can provide a quick fix, but it is not a long-term solution. It is best to charge the battery fully to ensure it has enough power to start the car on its own. Jumpstarting should only be used in emergency situations.</p><h2>5. How often should I charge my car battery to prevent it from dying?</h2><p>It is recommended to charge your car battery at least once a month to maintain its health and prevent it from dying. If you are not using your car frequently, it is best to invest in a trickle charger to keep the battery charged at all times.</p>

1. How long does it take to charge a dead car battery?

The time it takes to charge a dead car battery can vary depending on the type and size of the battery, as well as the charging method. On average, it can take anywhere from 4-24 hours to fully charge a dead car battery.

2. Can I charge a dead car battery overnight?

It is not recommended to charge a dead car battery overnight, as overcharging can damage the battery and potentially cause it to explode. It is best to monitor the charging process and disconnect the battery once it is fully charged.

3. How do I know when my dead car battery is fully charged?

Most modern car battery chargers have built-in indicators that show when the battery is fully charged. If your charger does not have this feature, you can use a voltmeter to measure the battery's voltage. A fully charged car battery should have a voltage of around 12.6 volts.

4. Can I jumpstart a dead car battery instead of charging it?

Jumpstarting a dead car battery can provide a quick fix, but it is not a long-term solution. It is best to charge the battery fully to ensure it has enough power to start the car on its own. Jumpstarting should only be used in emergency situations.

5. How often should I charge my car battery to prevent it from dying?

It is recommended to charge your car battery at least once a month to maintain its health and prevent it from dying. If you are not using your car frequently, it is best to invest in a trickle charger to keep the battery charged at all times.

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