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Another example of Lipo fires.

There is an old saying that nature abhors a vacuum, but strictly speaking nature abhors imbalance and anything that is out of balance is inherently unstable to one degree or another. Batteries, or any other form of stored energy, are fundamentally unstable and like other sources of stored energy need to be stored in controlled manner to be safe. Gasoline needs to be stored in a closed container away from heat and water behind a dam needs to be released carefully,
In like manner, LiPo batteries need control chips to regulate the charge and discharge currents, and chargers need to be designed properly and built reliably enough to avoid exceeding the voltage and power ratings of those control chips.

The more energy that anything (gasoline, LiPo, fission reactor) can generate and/or store in a tightly confined volume the greater the potential danger. Lots of stored energy in a very small volume is literally the definition of a bomb, and the more we expect batteries to have lots of storage capacity in a small shape the closer we are to specifying a potential bomb. Consumers are literally demanding more and more powerful bombs being created for their electronic goods.

LiPo batteries get lots of press when one self destructs ... or is destroyed such that it's stored energy is released undesirably ... but I'd bet there are more gasoline or electrical fires every day than there are LiPo fires. Still, the better the battery the greater the potential danger. Physics is physics.
 
Ouch. You have to be wary of USB chargers - they're not all made the same unfortunately. These days I only ever charge my devices when I physically in proximity to keep an eye on the charging. That means no charging while sleeping etc.

Agree. USB chargers vary from some pretty good ones to some I wouldn't trust to run the 4 watt USB fan on my desk.
 
There is an old saying that nature abhors a vacuum, but strictly speaking nature abhors imbalance and anything that is out of balance is inherently unstable to one degree or another.
Your underlying point is a good one but I'm going to get a bit pedantic here, just for the sake of a little extra clarity. Apologies in advance.
Batteries, or any other form of stored energy, are fundamentally unstable and like other sources of stored energy need to be stored in controlled manner to be safe.
There's a fundamental difference between an unstable system and a metastable system, and all stored energy systems are, by design, metastable, not unstable. An unstable system will spontaneously release energy, whereas a metastable system requires a perturbation to do so.
Gasoline needs to be stored in a closed container away from heat and water behind a dam needs to be released carefully,
Exactly - and those are the design constraints. Heat is the primary perturbation that allows chemical energy release from gasoline by taking it over its chemical activation energy barrier to ignition. A dam is itself the gravitational activation energy barrier, although the energy release in that example is achieved by bypassing the barrier rather than going over it.
In like manner, LiPo batteries need control chips to regulate the charge and discharge currents, and chargers need to be designed properly and built reliably enough to avoid exceeding the voltage and power ratings of those control chips.
Those are design constraints to maintain the metastable state of the battery, i.e. preventing internal discharge due to physical damage.
The more energy that anything (gasoline, LiPo, fission reactor) can generate and/or store in a tightly confined volume the greater the potential danger. Lots of stored energy in a very small volume is literally the definition of a bomb, and the more we expect batteries to have lots of storage capacity in a small shape the closer we are to specifying a potential bomb.
That's not quite correct - a bomb requires both energy density and high energy-release rates. There are plenty of high-energy-density systems that are unable to release the energy fast enough to explode, or which have insufficient available working fluid to do rapid mechanical work on the surroundings - the definition of an explosion. LiPo batteries are an example of a system that can be driven from a metastable state (good) to an unstable state (bad) by a thermal perturbation, leading to a pressure burst (the fast energy release component) of a system that by that stage contains numerous flammable products.
Consumers are literally demanding more and more powerful bombs being created for their electronic goods.
Well you are certainly not going to get a job in LiPo marketing.
LiPo batteries get lots of press when one self destructs ... or is destroyed such that it's stored energy is released undesirably ... but I'd bet there are more gasoline or electrical fires every day than there are LiPo fires. Still, the better the battery the greater the potential danger. Physics is physics.
Agreed. All things considered they have a pretty good safety record but yes - when they let go it can be impressive.
 
In the early days of flying drones in Canada with Lipo batteries, the only way to get permission from Transport Canada was to have an expensive class D fire extinguisher available. This was relaxed to a bag of sand eventually and a fire prove blanket. But I still have the bag of sand in the back of my car, never had to use it but it’s now built into my DNA.
 
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And make sure your dogs don't get hold of them either.
 

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Is that the charred remains of the dog?
 
Many of you know who captaindrone is and if not he has been around for many years. He had a very close call with a Lipo fire.
Seeing this often enough made me purchase the charging bag. I can put all three batteries in and let them charge up without worrying about it any more. The bag is zipper closed and the wires go through the side. Good to 2,000 degrees. I've never had a problem with my batteries for the M2Z, but I did have one start to expand on my Mavic Air.
which I discontinued using.
 
I have a old WW2 ammo box that I have drilled some holes into to let out the gasses if a fire starts inside. Use it mostly for battery storage. I have a room down in my basement that is not finished and I use that for my charging station. Metal table, cement floor and cement block walls. During the summer time I charge my batteries out in the BBQ with the lid down. After 8 years so far so good.
 
I love this forum, your always learning something new. I don’t want to show my lack of education, I’m just a boy from the bush but I had to look this one up.

anxiety; mental uneasiness.
"she sensed her friend's perturbation"
  • 2.
    a deviation of a system, moving object, or process from its regular or normal state or path, caused by an outside influence.
    "these shifts and swings in wildlife populations are possibly related to climatic perturbation.

 
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Seeing this often enough made me purchase the charging bag. I can put all three batteries in and let them charge up without worrying about it any more. The bag is zipper closed and the wires go through the side. Good to 2,000 degrees. I've never had a problem with my batteries for the M2Z, but I did have one start to expand on my Mavic Air.
which I discontinued using.
I purchased one of these charging bags as well. Just incase…and I never leave home while they are charging.
 
Your underlying point is a good one but I'm going to get a bit pedantic here, just for the sake of a little extra clarity. Apologies in advance.

There's a fundamental difference between an unstable system and a metastable system, and all stored energy systems are, by design, metastable, not unstable. An unstable system will spontaneously release energy, whereas a metastable system requires a perturbation to do so.

Exactly - and those are the design constraints. Heat is the primary perturbation that allows chemical energy release from gasoline by taking it over its chemical activation energy barrier to ignition. A dam is itself the gravitational activation energy barrier, although the energy release in that example is achieved by bypassing the barrier rather than going over it.

Those are design constraints to maintain the metastable state of the battery, i.e. preventing internal discharge due to physical damage.

That's not quite correct - a bomb requires both energy density and high energy-release rates. There are plenty of high-energy-density systems that are unable to release the energy fast enough to explode, or which have insufficient available working fluid to do rapid mechanical work on the surroundings - the definition of an explosion. LiPo batteries are an example of a system that can be driven from a metastable state (good) to an unstable state (bad) by a thermal perturbation, leading to a pressure burst (the fast energy release component) of a system that by that stage contains numerous flammable products.

Well you are certainly not going to get a job in LiPo marketing.

Agreed. All things considered they have a pretty good safety record but yes - when they let go it can be impressive.
Joe Friday strikes again!! Can’t argue with someone from L.A. over science when “L.A.” is Los Alamos!
 
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