I’ve been thinking lately about dangers of exploding Li-ion battery. And precisely - the construction of li-ion powered LED flashlight.
Most flashlights have metal body with tightly screwed ends, commonly with protection of IP68 rating.
Let’s assume, that board protections in the flashlight fail - the battery is damaged and it ignites - what would happen?
Does it not create a pipe bomb? What happens when the battery takes on fire inside? Are the lights constructed in a way, that they vent out the possible pressure? Or it basically risks an explosion? Maybe screwing is not so tight, that it just let’s off the pressure?
Let’s take an example of Acebeam E75 for reference, but we can discuss any flashlight.
Have you witnessed such battery explosion inside flashlight? Maybe some YT video?
As @gravelmonkey suggests, this was all discussed many years ago, highlighted at the time by the popularity of vape mods. There was very little information on wattage and amp draw out there. People were building vape mods that pulled 30A and expecting any old 18650 x 2 to power it. Quite a few explosions and horrific pictures at the time I remember.
Problems occur when overloading, or having a weak battery family member in multi cell situations like laptops, vapes, and some torches. Your Acebeam E75 pulls about 12A on turbo, so it needs a 15A - 20A battery and it’ll be good. 10 years ago this kind of info wasn’t easily available, and neither was the information about how dangerous this battery technology is.
It still feels to me like Li-ion batteries and more so, the products they were powering, were just dumped on the market with consumerism coming way ahead of safety. I have a friend who’s a fireman, he used to keep telling me horror stories about cheap Chinese hoverboards, scooters, and e-bikes catching fire while on permanent charge at the foot of the stairs.
I have some flashlights that are going to play with fire in the coming months. One will get too close to a simulated Sun. A few batteries are going to experience short circuits. Without penetration. One will be connected to a car battery. At this time I have ruled out a direct connection to AC power. All for science. Stand back.
Edit. There may be penetration. But that has already been done many times and we know the results.
This video explains why I don’t expect catastrophic results from most of my experiments. Heating while in a flashlight will provide some different results. I will include a few 21700 batteries.
One way of preventing catastrophic failure would be to retire aging cells early. I actually have a question about that. At what point do you decide the internal impedance of a cell is too high to keep using it? I have a Samsung 30Q that is at 76 mOhms and the factory stated impedence is 26 mOhms and I’m not sure if that’s an issue or not.
What happens when the battery takes on fire inside? Are the lights constructed in a way, that they vent out the possible pressure? Or it basically risks an explosion? Maybe screwing is not so tight, that it just let’s off the pressure?
