Battery drove with no alternator, now what?

[maketracks]

Drove two batteries with no alternator down to where the car stopped running and a charge/new battery was needed. It is on the only charger I got, which is a 2A slow manual one. Are these batteries done for?

I got one AC Delco Group 75 and the other one is an EverStart, same group size. Both are depleted. The ACDelco was run down last week or so; The EverStart, today. The EverStart was IMMEDIATELY charged back up, the ACDelco sat dead for a few days and just got fast-charged and is now getting slow-charged. The multimeter appears to show me the amperage of the current going in.

I also have a brand new alternator sitting in the backseat, and a used one that missed me in the mail. Neither one are where they are supposed to be: On the engine, in the belt.

They both received a parts store 35-minute charge, and the store says the AC Delco tests out at about 500CCA, no report generated on the other one, earlier in the day, which stopped running when I got home, and had connected to my charger while it ran. Getting it to a shop to take a look-see.

What can I expect from these batteries? They cost $250 combined total. (Yeah, I know.) So, needless to say, I have an interest in charging them back up. Will letting it sit for DAYS on the slow charger get them there?

 

[Donald]

if you left the lights on that would drain it to zero. But if you only ran it down until the car stopped then that was probably around 10V. Charge it up via AC charger and I think there is a good chance things will be fine.

 

[HerrStig]

I think both should be OK, but YOU need a bigger charger. 2 amps is barely enough to cover the leakage current. If you don'r exceed the leakage current you won't put in any charge. Now, it is sometimes tha case that modern batteries won't come back after a full discharge, even when close to new, unless they are "deep cycle" batteries, but deep cycles are sold for things like golf carts, not cars. It is worth the try. You have spent enough on batteries to buy one heck of a good charger. Try your local Harbor Freight which is think is in Warwick. 8 to 10 amps ought to do.

 

[HerrStig]

Originally Posted By: maketracks
Drove two batteries with no alternator down to where the car stopped running and a charge/new battery was needed. It is on the only charger I got, which is a 2A slow manual one. Are these batteries done for?

I got one AC Delco Group 75 and the other one is an EverStart, same group size. Both are depleted. The ACDelco was run down last week or so; The EverStart, today. The EverStart was IMMEDIATELY charged back up, the ACDelco sat dead for a few days and just got fast-charged and is now getting slow-charged. The multimeter appears to show me the amperage of the current going in.

I also have a brand new alternator sitting in the backseat, and a used one that missed me in the mail. Neither one are where they are supposed to be: On the engine, in the belt.

They both received a parts store 35-minute charge, and the store says the AC Delco tests out at about 500CCA, no report generated on the other one, earlier in the day, which stopped running when I got home, and had connected to my charger while it ran. Getting it to a shop to take a look-see.

What can I expect from these batteries? They cost $250 combined total. (Yeah, I know.) So, needless to say, I have an interest in charging them back up. Will letting it sit for DAYS on the slow charger get them there?
"CCA" really only tells you how fast the water flows out of the bucket, not how much is in there. The battery "amp hour" rating is what you need to look at.. if it is rated at say 70 amps for an hour, you are going to have to put about MORE than that IN to fully charge it. With a 10 amp charger, 2 amps going to leakage, figure about 12 hours at least.

 

[Win]

Starting batteries are not meant to be deeply discharged, so it is very possible that they are damaged.

They may still provide a good, or even normal, service life. Time will tell.

Your 2 amp charger should fully charge the batteries, but it will take a long time, which is the way I would charge a deeply discharged car battery.

 

[bama7x57]

I think you're good. My daughter has left her lights on all day a time or two. Her battery was DEAD, but seems to have not suffered any negative effects.

 

[TFB1]

Originally Posted By: Donald
if you left the lights on that would drain it to zero. But if you only ran it down until the car stopped then that was probably around 10V. Charge it up via AC charger and I think there is a good chance things will be fine.


Agreed...

 

[Chris142]

Charge one for 24 hrs then the other. Or buy a better charger.

 

[UNC017]

You may have knocked a little life off the batteries, but with a good slow charge they should be fine. My experience is that batteries can take a few deep discharges in their life without problems, but not TOO many.

 

[The_Jeff]

Whatever you do get the batteries out of the cold. They can freeze if discharged and that will ruin them.

There may be a way to rig a PC power supply to charge the batteries. Google around.

 

[Donald]

I would charge with a 10-15 amp charger. A 2 amp charger is either made to be a maintainer or for lawn tractor batteries.

 

[Doog]

Originally Posted By: Win

Your 2 amp charger should fully charge the batteries, but it will take a long time, which is the way I would charge a deeply discharged car battery.


+1 this ^^^

 

[GSCJR]

If you can, first check the level of the electrolyte. Second, if the levels are ok, charge the batteries at a rate of 5 to 15 amps overnight and re-check. My findings are that typically, when an automotive battery is discharged more than once it will shorten the life expectancy of the battery.