So how volatile are these little batteries anyway?

I had changed few swelled dashcam batteries over years and this happening in very mild Irish weather where we have only two seasons all year around: autumn-spring and spring autumn :). Luckily they were not "exploded", just swelled, but you never know when worst case scenario may happen.
I keep two pcs as a sample to show to my local customers when trying to explain what are the risks of using battery based dashcams vs supercaps dashcams.

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:eek: While this might be an extreme demo, a little shock and awe doesn't hurt in the make you think department. Supercapacitors are the way to go for DashCam products. :)
I haven't read up on supercapacitors. But how fair is it to compare them without factoring in energy capacity?
A 3.7V 300mAh battery holds 3996J of energy.
A 6F capacitor charged to 3.7V holds 41J of energy.
About 100x difference.
If you want to compare usability or risk of sudden energy release, then you should really be looking at a 600F capacitor.
Alternatively compare the 6F capacitor to a 3mAh battery.
It would take some time for a 200 or 300mAh battery to degrade to 3mAh capacity.
And bear in mind that capacitors also degrade over time and fail. Look at how many computer motherboards fail after a couple of years because of using cheap capacitors.

Edit> Having said that, I had a childhood ambition to own a 1F capacitor, just because it was so extreme. I see you can now buy a 360F supercapacitor from Maplins for £13. Amazing.
 
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I haven't read up on supercapacitors. But how fair is it to compare them without factoring in energy capacity?
A 3.7V 300mAh battery holds 3996J of energy.
A 6F capacitor charged to 3.7V holds 41J of energy.
About 100x difference.
If you want to compare usability or risk of sudden energy release, then you should really be looking at a 600F capacitor.
Alternatively compare the 6F capacitor to a 3mAh battery.
It would take some time for a 200 or 300mAh battery to degrade to 3mAh capacity.
And bear in mind that capacitors also degrade over time and fail. Look at how many computer motherboards fail after a couple of years because of using cheap capacitors.

Edit> Having said that, I had a childhood ambition to own a 1F capacitor, just because it was so extreme. I see you can now buy a 360F supercapacitor from Maplins for £13. Amazing.

well the point is we don't need capacitors larger than the equivalent of a 3mAh battery so they are a lot safer

motherboards that fail are a bit different, some info here http://badcaps.net/index.php?s=a2371736be7e9d51899138d4f998f275&pageid=causes
 
this is a very informative thread.

I now know to step further back when shooting my LiPos with my BB gun.
 
Don't mess with puffed batteries- that outer 'bag' contains Hydrogen Fluoride gas, and one good whiff of it can put you in the hospital for awhile- or worse :eek: If you "just have to" then do it outside on a day with constant wind and stay upwind being sure nobody is downwind. That is actually the biggest danger with Lithium batteries, because if someone sees a fire in time, their first instinct is to throw the device outside and in the process they breathe those deadly fumes unwittingly. The potential for a major disaster is there with Lithium's, but the occurrence of events where someone is harmed are extremely rare given how many Lithium's are around. You'll win the lottery before it happens to you.

These things ain't toys people, so please don't play with them like that.
Phil
 
may not be the same issue as Samsung has been having, hard to say, not the first time they've had batteries fail but the timing of this one given the bad press Samsung have been having lately will probably stop them gloating, they possibly looked better recently due to Samsung's woes but just a reminder that anyone can suffer the same fate I guess
 
I think it have been concluded that what happen to the Samsung notes are batteries not being able to work ( expand ) freely due to phone shape and so pressure get things inside them to collide thats not supposed to collide.

I ws not able to relocate the article i read it in.

I do hope Tesla cars have a almighty good firewall above its battery ;)
 
So, is it really the in-car "Power Banks" we should be wary of, being higher capacity and also often stowed away in enclosed storage areas where a fire may not be noticed, and may be too late to remove?

As these banks would be used primarily for parking mode this adds further danger: temperatures in-car may rise to a danger point due to no air conditioning; we're not around to notice a fire.

I'm being scared off the LiIon type of power bank for parking mode power supply due to reading here and elsewhere. In comparison, how safe is LiFePO4 power? I can only find one 6000mAh unit, here: http://www.colorfly.eu/DEBOCH X6000/index.html

This is 4 times the price of a typical LiIon power bank, but would it be a wise buy?
 
personally I think parking mode is a flawed application however you choose to power it, the potential gain is far less than the losses in most scenarios
 
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This is 4 times the price of a typical LiIon power bank, but would it be a wise buy?
All these powerbanks contain enough power to create a fire if something goes wrong, unlike the small batteries used internally in most dashcams.

Because car interiors are not made of self extinguishing materials like house furniture is, starting a fire in a car is very bad news.

They should not catch fire until well above any temperatures you will get in a car, unless it is already on fire, or they are physically damaged, or there was a manufacturing fault. Manufacturing faults are rare these days but can still happen, especially to the cheaper batteries. They are reasonably safe, even at car interior temperatures, the problem is that the consequences of a failure are very serious.

I think the wise thing to do, whatever type you get, is to install it in a position or enclosure that will prevent any fire from spreading, mainly to stop burning plastic case dripping onto carpets. If you install it in the engine compartment beyond the firewall then you have nothing to worry about, whatever type you get.
 
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