How long to charge a battery?

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I know it's going to take all night. I'm just wondering if there is a way to guestimate how long it will take to recharge a run down 12v car battery?

I left the interier light in moms car on for a few days.
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Battery volts were 2.46v. The battery is rated @ 525A @ 0*F and 650A@ 32*F.

I'm using a 10A microproceser controlled charger. It's supposed to taper off as the battery is charged.

Is there a way to figure the rough charge time?

I'm really just curious. I'm going to leave it on all night and hopefully the green "fully charged" light will be on in the morning.
 
You'll get starting power by AM. My 6 amp can do it to a huge dodge ram truck battery.

My motorcyle battery is rated 16 amp-hour and is 1/4 the size of a car battery. So figure 70 amp hour. There you go.
 
Originally Posted By: justinf89
find out the batteries rated Ah and divide by 10A from your charger. There's your hours.
Great! Thanks. It's a 80A/H battery so in theory it should take 8hrs to charge.
 
This is close..... but divide the amp hour rating by the chargers actual output, not its "10 amp" rating.

Likely it is charging at closer to 8 amps at first, and declining to 1 or 2 amps over a 24 hour period.

As another poster said: It will easily start in the morning, let the car alternator/regulator take over after that. One day of normal use and it will be back to full charge.
 
I put it on the charger @ 5:30Pm tonight and I will take it off @ 6:30A tomorrow. The charger has a green light to tell when it's fully charged. I'm not one of those people that will jump start the car, run it 10 minutes and turn it off thinking it's now charged.

I know better.

I'm sure it will be fine by 6:30A tomorrow.
 
If you are able to, verify the electrolyte level once the charge process completes; top it off with distilled water if needed. Wear safety glasses, please!

The battery will be getting a relatively aggressive (albeit managed) treatment overnight.
 
If the battery is more than 3 years old, it's probably hosed after this near-death experience. A new battery can handle a total drain but an older one can't. If it's old I'd replace it at the earliest convenience
 
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