Hi, first post, cool site.
I just bought a portable battery jump pack (Super Start, 1000 peak amps) and I called the manufacturer’s consumer information line as well as the store and they didn’t seem to know much more than was on the instruction sheet.
It says “don’t attempt to jumpstart a frozen battery”. Aren’t all car batteries in the winter up in the northern climes regularly frozen? Does this mean the portable pack is only to be used when above 32 degrees? What would happen if it was used below 32? Do I have to take the battery inside to warm up? Is there much risk in jump starting in general as far as an explosion?
Also, along those lines, the instructions don’t address whether or not the pack itself will work when IT is below 32 degrees, such as would be the case if it’s carried in the trunk during the winter.
Thanks,
Ed
Batteries do not freeze at 32 degrees. Do a little Googling and find out for yourself.
The information I found indicates that a fully charged battery will freeze at -77 degrees. On the other hand, a completely discharged battery will freeze at 20 degrees. Batteries at various states of charge have freezing points in between those temperatures.
In the rare event that a battery actually freezes it’s no good any more, and must be replaced.
If you have a good battery and the charging system in your vehicle is working correctly you really shouldn’t have to worry about winter. If you need to jump start your vehicle on a regular basis you have a problem with one or both of the above.
And, yes, there is always a danger of explosion when jump starting a vehicle. That’s why you should make the ground connection last, at a point on the engine or chassis, and not at the negative battery terminal.
And keep your face away from the battery being jumped.
A normally charged battery will not freeze until it is very very cold. However an exhausted battery (What other kind of battery would need a jump?) is a different matter and they can freeze at warmer temperatures. I don’t think you will find even an exhausted battery freeze at 32?, but they will freeze at a higher temperature than a fully charged battery.
The posts so far are correct, batteries rarely freeze. A fully discharged battery could freeze quicker than a good battery with a full charge.
So, how do you know if your battery is frozen? If the dome lights or any interior lights go on, no matter how dim, the battery is not frozen.
If there is no signs of electrical life in the battery at all, the battery might be frozen. If it is dark get a flashlight and carefully examine the outer case of the battery. If you see any swelling, or cracks in the plastic it is frozen and totally useless. Don’t attempt to jump start the car if you observe a swollen or cracked battery. Just go and get a new one.
A dead (junk) or discharged battery can freeze. A sound and fully charged battery can not. It’s the specific gravity of the sulfuric acid that determines freezing point…
When I was a teenager pumping gas at a local Texaco, I remember several customers who would try to start their cars on cold mornings, The cars would not start and in the process of trying, the battery became drained. So they got another ride to work and when they came home from work that evening, their battery was frozen.
Take the warnings about explosion risks when jumping batteries very seriously. I had one explode on me. I’m lucky to have my eye sight.
The last jumper cable connection will create a small spark. If that spark occurs around the hydrogen-oxygen fumes at the top of the battery, you can cause an explosion. When it occurs, you’ll get the plastic from the top of the battery shot into your face like shrapnel, you’ll have battery acid showered all over you (including your eyes), and it will sound like someone set off an M80 or Cherry Bomb in your ear. Not a pretty site.
The jump pack can used in any temperature as long as it’s fully charged.
The jump pack can carried/left in the vehicle in all temperatures. It should have a test button that when pressed indicates the state of charge of the jump pack. Just check the state of charge on occation to make sure the jump pack is fully charged and not as dead as the battery you’re trying to jump.
I leave my jump pack in my vehicle all winter long. And have only had to recharge it once even after performing a couple of jump starts with it during the winter.
Of course, this also depends on the starting amperage capacity of the jump pack.
Tester
I have seen one battery that was cracked from being frozen,discharged batterys will freeze.
Agree; batteries that are comletely flat will freeze somewhere around 20F. That’s when the water in the acid will freeze and likely split the casing. If you live in Minnesota, park outside, and you have a flat battery in January, it’ll like be “toast”. That’s why we always recommend taking the battery out of a longterm storage car or put a battery minder on it to keep it charged up!
I wish you luck with your jump pack, but my experience with them was disappointing. They seem more prone to fail than even the cheapest battery. And when not needed and left off the charger for extended times they are usually too weak to do the job. With several vehicles and a boat it is convenient for me to keep batteries from vehicles not in use hooked up in paralell on a trickle charger and when a jump start is needed a good battery is always handy.