I dropped my car off last week at a storage facility. The place is unheated. I will be dropping by either today or tomorrow to put a car cover on it, plug the exhaust tips with old rags, etc, etc

Should I unmount and take the battery home with me? Or can I just disconnect the negative terminal and leave it in the car? I want to avoid using a trickle charger.

 

Since it's "unheated", take it home and put a "smart" charger on it. Do NOT leave the battery sit on concrete. Put a piece of wood under it.

 

[QUOTE]Originally posted by xviper
[B] Do NOT leave the battery sit on concrete.

 

Do you like your concrete?

Batteries are filled with Sulfuric acid. This acid will wreak havoc with most anything that it touches, including concrete.

 

It may be true that the acid is bad for concrete but assuming that the battery case will not leak, this isn't the real reason why you shouldn't place a car battery on cement floors.
I don't have the technical explanation for it but wet cell batteries on a cement floor loses their charge very quickly. Something to do with the cement being a sort of "heat sink", making the battery much colder than the surrounding air and also having the ability to "draw" current out of the battery. Maybe someone can give a real scientific description of what happens here.

 

[QUOTE]Originally posted by xviper
[B]It may be true that the acid is bad for concrete but assuming that the battery case will not leak, this isn't the real reason why you shouldn't place a car battery on cement floors.
I don't have the technical explanation for it but wet cell batteries on a cement floor loses their charge very quickly.

 

I must admit, I've never "stored" a battery or a car for that matter. This phenomenon sounds rather strange to me.

I would also like a more scientific explanation. I'm having a hard time understanding how, other than the heat loss, that this would occur. I can think of no electrical explanation for this. The battery case won't change it's conductivity properties because it's sitting on concrete. It has to be connected with the heat loss.

Hmmm, anyone with a better explanation?

 

In the old days, the rubber case batteries would actually leak a little, or the non-sealed batteries (with caps) allowed a non visible amount of acid to dribble down the side. Placing this battery on the concrete set up a very minute current draw to the concrete, accelerating the drain. Newer sealed batteries do not
suffer from this malady, but they do, just like the old ones, lose about 1 percent of charge per month. After a long winter, this could be just enough to not start the car. Perhaps the worst part is that if you do not maintain a charge, the plates will sulfate. After a point, this is irreversible. Some technologies, such as Solargizer, can reverse a lot of this, but the best advice is to get a low amperage, self regulating charger, such as a Deltran Battery Tender, and leave it on all the time. It will not boil the battery like other types, and by maintaing a full charge you will not lose efficiency. I have batteries eight years old going like new with this method. Unless the battery plates shake loose, the sulfation it what kills it. Unless the battery freezes due to low specific gravity, cold slows down current loss in a battery without a drain on it. Set it on newspaper. If the paper turns brown, you've got an acid leak. Otherwise, set in on the concrete floor.

 

Thanks, Chipperman. I can relate to the old rubber cases and certainly believe the trace of acid down the case. I have seen the same type of thing with "carbon traces" on printed circuit cards in older TV's. That may have started this "story", but I feel as you do, that you should not have any leaks with a new style battery.

I can also see how the battery is more likely to freeze with less than a full charge.

Thanks,
Bob

 

chipperman is correct. I and many others have been "sucked" in by this "tale" from times long gone when battery technology was more primitive.
See here:

http://www.inct.net/~autotips/battmyth.htm

Although the information in this site can also be "unscientific", it sounds good. So store your battery on concrete if it's not leaking or prone to leak.