Is 5month-old battery a garbage if completely drained???? - PeachParts Mercedes-Benz Forum

ProV1 · #1 11-14-2006, 10:20 AM

When I bought my 97 E420, I noticed that the past owner put in an aftermarket EXIDE group49 battery. It didn't have a vent tube, but on the side it said "APR 06". So I'm guessing this is a fairly new battery.

Then last month I left the doors open (made sure all lights were out), and traveled for 6 days and the battery was dead when I came back. Car wouldn't even crank and all lights were dead.

It was a struggle to even jumpstart the car, but I managed to start her again and all seemed fine. But recently I'm noticing that it takes alarmingly long time (sometimes 3-4 seconds) of cranking to start the engine. I'm driving the car everyday but I'm afraid if I park the car for 4-5 days it will die again.

Does an even relatively new battery get destroyed if you let it completely drain out? I wonder if I should just bite the bullet and replace the battery now. Hopefully I don't have another bigger problem like a battery drain somewhere... argh

michael cole · #2 11-14-2006, 10:48 AM

have you fully recharged the battery?

david s poole · #3 11-14-2006, 10:54 AM

buy new battery.if you allow auto battery to go completely dead it will lose a large amount of it's capacity because the lead plates will have lead sulphate on the surface.buy a marine version of the same battery and it will not have that problem.meantime you need a bunch of low voltage faults cleared out of the computers.

gmercoleza · #4 11-14-2006, 11:00 AM

Once fully discharged, sulphating will damage the battery, especially if left that way for a prolonged duration. This is not to say that the battery is completely useless, however it will never hold nearly the same charge as it did when new.

jcwells · #5 11-14-2006, 11:05 AM

One complete discharge is not quite that bad. I do recall reading that it kills about 10 -15% of battery life. If it is only 5 months old, I would charge it and continue using it.

You should also consider some of the newer battery chargers that charge better (3 stages), and often have a desulphate mode.

John

msethk · #6 11-14-2006, 11:10 AM

you might try looking up the local exide distributer and see what they say. it would seem there is some warranty on the battery.

Tomguy · #7 11-14-2006, 11:14 AM

My Exide 49 drained out completely leaving the trunk open over the weekend. It was about 4 weeks old at the time (at MOST). A jumpstart, and then cruise for about 30 mins, and the battery has never hiccuped since.

forp · #8 11-14-2006, 11:36 AM

You may find some useful information here:

http://www.peachparts.com/shopforum/showthread.php?p=1057827

mpolli · #9 11-14-2006, 01:21 PM

If it was only left for 6 days then it was probably not drained to zero. Did you measure the voltage that was on it?

When you charged it did you note how many hours it took to charge it at how many amps? For example when I have had a battery that is "end of life" it will take a charge of 4 amps (from my charger) but only for a half hour or so. That is a bad sign. On the other hand if it takes 4 amps for 10 hours or more and then finally tapers off then it is probably fine. Bigger chargers will charge at a higher rate and smaller at a lower rate but this gives you an idea. I have a "regular" battery charger that I think says it can do 6 amps.

Mike

ProV1 · #10 11-14-2006, 01:38 PM

oops. since i dont have a charger, i simply jumpstarted the car and drove her for a few hrs.

should i buy a 'charger' and try charging the battery? does it plug into the cigarette lighter socket?

Kestas · #11 11-14-2006, 01:48 PM

I believe the best way to charge any battery is by trickle charging. That's somewhere in the 1/2 to 2 amp range. Until I learn more about batteries, I always charge mine by trickle charging for two days.

Here's a link that may help some people:
http://www.repairfaq.org/ELE/F_Car_Battery.html

ProV1 · #12 11-14-2006, 01:56 PM

Quote:

Originally Posted by Kestas

I believe the best way to charge any battery is by trickle charging. That's somewhere in the 1/2 to 2 amp range. Until I learn more about batteries, I always charge mine by trickle charging for two days.

Here's a link that may help some people:
http://www.repairfaq.org/ELE/F_Car_Battery.html

thanks kestas, i'll order a trickle charger and give it a try.

ProV1 · #13 11-14-2006, 01:58 PM

but can't the alternator fully re-charge the battery as well if you drive for a long period of time?

ProV1 · #14 11-14-2006, 02:00 PM

found this : how does it look?

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=42292

Kestas · #15 11-14-2006, 03:22 PM

I was once told that trying to charge a battery that's been deep-discharged by running it on the road can be tough on the alternator. I believe it can overheat the alternator and in the worst case, fry it.