Storing an Auto Battery?

[CWLee]

I've ended up with an extra car battery. Took it to a local auto parts store, to see if it was worth anything. The clerk tested it and said it was "almost as good as new." He said it showed 12.5 volts after a load dropped it to 11.5 and then it came back. He said it was in good shape. So, maybe I should keep it. It is 5 years old, with a warranty for 6 years. I told the clerk I'd just keep it in the garage as a spare, and he said that was a good idea, but not to let it sit on concrete. He said if it was stored on concrete it would "drain away" to nothing within a couple of weeks. I asked "What about placing it on wood?" He said he didn't know about that, but for sure not to store it on concrete.

Do any of you have any evidence to support his idea that storing a good auto battery on a concrete floor would damage it? In general, what is the best way/place to store an unused but good auto battery?

Thanks.

[Rod Speed]

battery on a concrete floor would damage

Nope, its an urban myth

?q=battery+store+concrete

Its crucial to keep it reasonably charged, they dont like being stored flat.

[Bob F]

Just be sure to keep it charged. If you don't. it will die.

The concrete thing is likely just an old wives tale.

[Don Klipstein]

The concrete stuff is a persistent urban myth. I have yet to hear a chemical or electrochemical explanation for the claimed effect of concrete. I know someone who worked at a place manufacturing automotive batteries, and he says that's a myth.

The thing is to keep it charged. It will self-discharge, and need its charge topped off something like monthly.

People who have batteries die from sitting on concrete have them die because they sit long enough to get badly discharged, and then a bad sulfation process occurs. On concrete is merely where automotive batteries mostly meet such a fate.

- Don Klipstein ( [e-mail])

[ransley]

has good info, so do other sites you should google. Wash it real clean thats partialy how it discharges, and as I understand it must be maintianed 100%, a battery maintainer is what you need. Ive ruined many batteries by not using a maintainer from sulfation, it happens real fast. 12.5v isnt charged, its sulfating now.

[salty]

In the old days, batteries had hard rubber cases and setting them on concrete could result in a ruined battery. Modern Batteries are not made of rubber any longer, so it really doesn't matter. I usually put mine on a piece of wood just out of habit, I guess. The more important issue is to make sure you keep it charged and the water at the proper level.

[HeyBub]

You need a float charger.

[gfretwell]

The concrete "myth" persists because the battery might still damage the concrete if there is any residual acid on it or you boil some out overcharging it. The piece of wood is just for peace of mind.

[Gordon Burditt]

Are you sure that the correct interpretation isn't: Don't store the battery on concrete; if it leaks the battery acid will DESTROY OR STAIN THE CONCRETE?

Some stores find it worthwhile to stock Concrete Rust Remover and advertise it for removing battery acid stains, so there's reason to believe leaking batteries might damage the concrete.

[tnom]

Actually yes and no. A auto battery setting motionless and staying at a constant temperature can stratify the chemicals within and harm the battery. What better way to do this than set it on a very still vibration less hunk of concrete that will also hold a fairly constant temperature.

[Stormin Mormon]

I'd suggest to store the battery where it will not get freezing or hot temps. Cellar, is good. Cement? Dunno. Might be an urban legend, but wood is cheap and why take the chance.

I had a Horrid Fright float charger hooked to my marine battery. Boiled the battery dry, and killed it. If you do use a Horrid Fright charger, run it about an hour a day, using a lamp timer.

[Jim Yanik]

"Stormin Mormon" wrote in news:h4tk19$g60$ [e-mail]:

I bought one of those HF $3 digital multimeters,checked it and it read a fresh 1.5 volt alkaline battery at nearly 2 volts,took it back for another,that read a more reasonable 1.6 volts.

I would check the calibration of any HF electrical product.

[clare]

It'supposed to be an "old wive's tale" but I never store batteries on concrete. I've had them go bad stored that way in the past (ok - they were rubber case tar-toppers, so it's a while ago) - but I always have either a board or a plastic rack to store them on - can't hurt.

[stan]

The only explanation have ever seen is that back in the old days (the

1920s etc.) the battery cases then used were more porous than modern plastic ones and in some instances and in damp conditions dampness could cause lime products in the concrete to leach into the battery acid! So the myth about not storing on concrete has continued into modern times! If the battery is not fully charged when put away and/or not given a refresher or put on trickle charge every few months it is likely to be useless a year from now. Sticking it on a refresh charge every few months for a few hours at a low charge rate will be best chance for conserving it. Measuring the voltage alone is not a very good indication of state of charge or overall condition of a lead acid battery. But the on 'load test' performed by the auto parts store should have been a good test. DO NOT NOW LEAVE BATTERY discharged.

[Rod Speed]

Pure fantasy from someone who doesnt have a clue about the most basic chemistry/physics.

[salty]

On the other hand, placing the battery directly on a slab might keep it cooler, and slow down the chemical reaction. That would help prolong the life of the battery. I keep my boat batteries in the boat all winter in New England for just that reason. I give them a charge about once a month. As long as a battery is kept charged, it will not freeze. It is better for the batteries than bringing them inside.

[salty]

Hardly a pure fantasy. Old battery cases were made of hard rubber containing carbon. They wrere, in fact, somewhat porous, and storing them on concrete DID ruin the battery.

This problem existed a lot more recently than the 1920's, but modern batteries are not cased in rubber.

[Stormin Mormon]

A charged battery has a lower freezing temperature, but it certainly can freeze. Given a choice, I'd prefer to store a boat battery in the warm cellar.

[Larry W]

In the _really_ old days some battery cases were even made of wood.

[Rod Speed]

[e-mail] wrote

chemistry/physics.

Corse it is.

Not by the mechanism he spelt out it didnt.

Separate matter entirely to the MECHANISM for that happening.