My battery got drained because I accidentally left my hazards on for a while. It didn't fully drain, I had about a 1/4 left on the gauge. Anyways, got it jump started, but now I am worried that I have damage the battery. My battery gauge reads the next bar below the half way mark which is 14, before I start the car. After I start it, the gauge goes a little above the 1/2 way mark. So what do you guys think?
Battery gauge
- Thread starter goped
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I think that the battery gauges on most cars, including the LC, aren't much more than high-end idiot lights.
Put the battery on a charger and get it back up to full speed if you're worried about it. Unless the battery is very old and nearing the end of it's service life, it's probably ok. That type of discharge is pretty common.
Put the battery on a charger and get it back up to full speed if you're worried about it. Unless the battery is very old and nearing the end of it's service life, it's probably ok. That type of discharge is pretty common.
Yeah the battery on a slow charge overnight to get it back to health. You should be fine.
well, it's certainly not good to have a starting-type battery be fully discharged and it may cut down on its expected life but it shouldn't go flat out dead after just one almost full discharge either. Try to avoid an overly fast recharge, those aren't great either I believe, although you'll read about folks who believe that they were able to "shock" their battery back to life. 
If you don't have one already, splurge for a $10 voltmeter and read the battery voltage without load, several hours after the last charge, note the temperature, and check a table. Should ideally be around 12.65V around 70F IIRC when fully charged. Or use a hydrometer. And see if it recharges properly.
[typo corrected, yes hydrometer, sorry, too much HVAC on my mind...]
If you don't have one already, splurge for a $10 voltmeter and read the battery voltage without load, several hours after the last charge, note the temperature, and check a table. Should ideally be around 12.65V around 70F IIRC when fully charged. Or use a hydrometer. And see if it recharges properly.
[typo corrected, yes hydrometer, sorry, too much HVAC on my mind...]
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I agree, put the battery on a trickle charger and it should be fine.
??? What information would a 'hygrometer' provide about the battery ???
??? What information would a 'hygrometer' provide about the battery ???
I think he meant hydrometer. Measures the specific weight of the fluid to figure out what's going on chemically with the battery.
If you drained it down it may take a few trips to the supermarket to get it back to full charge.
Keep an eye on it for a few days. If your really worried take the battery down to O'Reilly/Autozone and have them test it. They can also show you how to read the date code on the battery which will also give you an idea about weather or not to replace the battery as a PM measure.
Keep an eye on it for a few days. If your really worried take the battery down to O'Reilly/Autozone and have them test it. They can also show you how to read the date code on the battery which will also give you an idea about weather or not to replace the battery as a PM measure.
Here are the no-load voltage at various states of charge at 77 degrees, after resting with no charging for at least 3 hours. A hygrometer measures specific gravity of the electrolyte and is more accurate, but that is usually difficult to do on maintenance-free batteries, so voltage is more useful. A one-time accidental discharge of a regular starting battery won't kill it if it was ok to begin with. Repeated deep cycling of a starting battery will kill it. Ditto to the other posts; just trickle charge it for a day or drive around for a while.
State of Charge in Volts
100% 12.7
90% 12.5
80% 12.42
70% 12.32
60% 12.20
50% 12.06
40% 11.9
30% 11.75
20% 11.58
State of Charge in Volts
100% 12.7
90% 12.5
80% 12.42
70% 12.32
60% 12.20
50% 12.06
40% 11.9
30% 11.75
20% 11.58