well mrtuna it's like this
Smart charger should never fail and burn your house down,
Protection circuit in protected batteries should never fail,
Battery or MOD should never short out and blow your front teeth out,
Both batteries in a stack battery MOD should have equal charge and residual capacity and degrade equally,
Your MOD regulator should STOP conducting current when the input voltage is too low to provide design vaping voltage,
But .... happens.
If everything works as designed, and is designed well then the safety issue is on the other side of the attomizer, not the MOD side.
But users sometimes disregard the little hints that the MOD is trying to tell them, like I used to be able to vape for 12 hours off a charge, but now only 4. Or vapor has stopped, maybe it's just a clogged carto, I'll keep puffing and it will probably clear up.
Or, I don't really need to check this two cells with a voltmeter, they LOOK OK, and they are only 8 months old.
Out of all the ways that a Li-ion battery can hurt you I think the one that has the best chance of catching you by surprise is a cell that has been discharged below the "don't go that low point" and is put in a MOD with a "better cell" and you try and draw 2 amps off it. Good chance for a BLAM right then and there. The loop voltage (aw not again Rocket) has the Good cell with a lot of volts in series with a bad cell with no so many volts in series with a Genuine Joye 2.2 ohm atty (fact that there is a regulator in there doesn't matter at this point). The voltage in this series circuit can actually try and reverse charge the bad cell as soon as you pull the trigger. Not good.
The 3.0 volt Li-ion cells that are really 3.6 volt cells and sometimes get overcharged by 3.9 volt chargers and have a stupid little circuit board inside the cell casing to drop down to 3.0 to 3.2 as soon as you draw a little current can show 3.6 volts with a meter without any load and be bad. Have no capacity left in them. Measure good with a meter, ain't no good. Now under load they would show bad, but with no load could measure good.
Even if you didn't put one in backwards, the weak cell thinks it is in backwards as soon as current is flowing.
Some 5 volt MODs have a design problem. 2.5 volts from a bad cell and 3.2 volts from a good cell and the regulator has no problem giving you 5.0 volts. puff puff puff. Then the bad cell drops to 2 volts, and the good cell drops to 3.0 volts and the regulator will try it's hardest to give you 5.0 volts but just can't make it so you get maybe 4.5 volts to the atty. Sort of vapes, maybe a little weaker, but vapes. The regulator should STOP, but most keep on trying, all the way down to about 3 volts in and giving you 2.5 volts out, trying as hard as it can to give you 5.0, but it can't. It shouldn't try, it should stop when it can't output design volts, shut down, STOP. But most don't.
So what happens when you put a load on an almost dead Li-ion battery?
Blam
Damn, thought it was getting a little weak, guess I should have stopped.
Now, has your MOD been designed to deflect that blast away from your face?
Sure hope the previous has put your worried mind as ease.
Enjoy vaping,
Rocket
and I will not go back and read that to see if it really made any sense or not.
