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Safest way to thaw a battery?

Eager beaver
12-20-2004, 01:27 PM
Hi All,

I am stuck in Ottawa Canada in -44 Celcius weather.
Car wouldnt start this morning, along with everyones on the street.
I took my battery out because I am sure its frozen.
What the safest way to thaw it?
Is it bad to smoke around it? Just thought I would ask because it is sitting in my living room.

Any help would be appreciated.

Evil Result
12-20-2004, 01:46 PM
Your battery shouldn't freeze because of the acid... and if it does putting it in your house would be fine....and there's no problem smoking around it or using it as a beer stand just as long as the terminals don't make contact. :p

12-20-2004, 09:04 PM
A discharged battery will freeze. A fully charged one will not.
If your battery really did freeze, then it's ruined. All the lead plates will have warped and bucked, ruining the electrical connections and insulating pads.
A frozen battery will bulge out at both ends
But, at -44, even a fully charged battery will to almost squat, so it might just be cold. let it warm up overnight inside, then put it back in the car and see if anything happens. If nothing happens at all, its likely ruined.

12-21-2004, 12:21 AM
and there's no problem smoking around it

yes there is, batterys can let off hydrogen gas, which is explosive. keep the battery in the garage if you have one. put a blanket or something on it.

12-21-2004, 10:39 AM
A discharged battery will freeze. A fully charged one will not.

A fully charged battery will freeze at about -40F (-40 C also, since they happen to be the same at that point.)

A battery not fully charged will freeze well above tht point.

In any case, at about -40 the battery will no longer have any usable charge.

Bring it to room temperature and then test. It MIGHT be ok.

SR Racing

12-21-2004, 11:48 AM
Its also possible that its not frozen, but that the cold weather has brought out the weakness of the battery. A brand new battery should provide enough cold cranking amps at that temperature, but if the battery is on its way out, the cold may have exposed this weakness.

At the very least, taking it inside will make the battery operate like its 70 degrees. When you take it back outside you should have no problems

12-21-2004, 02:54 PM
The electrolyte in a battery is sulfuric acid. It is strong when the battery is charged and weak when the battery is discharged. The acid can cause severe tissue damage since it is approximately 36 percent sulfuric acid and 64 percent water. It will eat holes in clothing, burn skin, and can cause blindness. Even in the discharged state, at 12 percent acid, it can cause burns. Batteries produce hydrogen and oxygen gases when they are charging and discharging. Hydrogen mixed with oxygen is very explosive and can be ignited by a spark or a flame. This may explode the battery case. Taking a battery inside is bad news and should NEVER be done, its very dangerous and hazzardous to your health.

I you wanna thaw it out, like mentioned, do it in the garage and insulate it against the cold, but it will probably be fu**ed as freezing will have probably warped the plates within the battery, weakening it.

12-22-2004, 01:29 PM
Taking a battery inside is bad news and should NEVER be done, its very dangerous and hazzardous to your health.

Charging or discharging a battery in side your home is not a good move. However bringing one in to let it reach temperature is not a problem at all. Last time I looked Walmart, K-Mart and Sears have 100's of charged batteries sitting on the shelves with no adverse effect to their employees or customers. <g> We also have several here on our shelves in the showroom. (and we trickle charge them periodically).

It is not a good idea to charge or discharge one while in the home.

SR Racing

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