Credit card (aka money no object) survivalists and preppers are doing my head in with all their electronics.
Looking at their modern communications, navigation, and digital devices, they are all moving towards lithium-ion (Li-ion) power packs. Yet have you thought about being off grid and charging these miniature fire bombs and what can go wrong with them?
In a nut shell if things go VERY wrong its instant fire if not explosion.
So what causes a failure?
- Over charging or too fast a discharge (aka a short or massive fast current demand),
- Too high a voltage (thus current) applied when charging.
- If the cell gets physically crushed or pierced.
- Deep discharging below 2 volts per cell.
Initially the cells start to vent gas. Usually CO2.
Then as things get hotter it get nasty as the plastic and other materials start to melt and evaporate.
Next stage is smoke, then flames,
And the worse case thereafter is an explosion.
Let’s talk fire control or “hell its burning” what do you do?
Get rid of it is my immediate action as there is an explosion risk!
In short once a battery pack starts a thermal runaway (Posh name for burning itself to death) it’s going to keep going until all that power has dissipated!
The ‘experts’ say you can use water on Li-ion cells as the water may keep battery components cool enough to not overheat other things.
OK, I can see why the experts are saying this BUT once things get hot, that heat will set off a reaction in other cells within the battery pack.
Note:- Advice varies about the use of water.
As it’s your life that may be in jeopardy, I’d err on the side of caution and simply ditch the bitch ASAP!
Fire needs three things to burn, heat, fuel and oxygen.
Take one of those away and the fire goes out.
Except if a cell has gone into thermal runaway, the problem then is all that heat spills into other cells in the pack and that CAN CAUSE THEM to join in the fun and also thermly runaway.
Only there isn’t a definite timetable for this one i.e. they could all go ‘pop’ in seconds or cook gently till a ‘BIG POP’ occurs after a few hours. Bottom line? (sounding like a stuck record here) Ditch the bitch ASAP!
You can also use foam, CO2, or dry powder to control the fire.
That is fire control of everything else which is cooking off because of the heat from the damaged cells.
So is it any different for Ni-cad, Ni-Mh, or even Lead acid?
All batteries are storage for energy.
Apply a short or damage them and things will get hot, EXTREMELY HOT, usually QUICKLY.
Using any form of extinguisher will cool things down BUT AS BEFORE, until all that stored energy has dissipated as heat, battery fires are almost impossible to control if the fault is internal.What’s safe then?
- Navigation? Magnetic compass and those paper things i.e. maps.
- Communications? Apart from semaphore, flags, and yelling, not a lot.
- Digital devices? Why use them? What are you carrying that can’t be written down in a little book?
- Battery powered weapon sights? Now I could be wrong but I have never heard of a mercury button cell or alkaline battery powered red dot or holo-sight bursting into flames.
Until you tell me you know of one that did.
What’s a Li-po battery?
Li-poly and others), is a rechargeable battery of lithium-ion technology in a pouch format.
Used a lot in those personal drones that the geeky survivalist and prepper ‘must have’ as a toy.
I’ll discuss them next and if anything they are even more dangerous.