Semantics. Is a battery undergoing thermal runaway/venting "exploding"? Or merely "ejecting scorching hot gas and catching fire?" Maybe it's not blowing up like an IED, but either way I don't want it happening in my garage.
The difference between "can be ignited" and "massive bomb" is not semantics. Even new pouch cells are way safer than they used to be. Unregulated 18650 cells are quite safe if the correct circuitry is used. The only dependable way to ignite them is to smash completely open them at full charge.
Cool, you caught me being hyperbolic. They are not literally a massive bomb.
> Even new pouch cells are way safer than they used to be.
Right, because these packs filled with recycled cells are going to have the latest protections.
> Unregulated 18650 cells are quite safe if the correct circuitry is used.
Which is my whole point, I'm not sure I trust the guy down the street to correctly wire and have adequate circuit protection for his DIY battery pack in his garage.
> The only dependable way to ignite them is to smash completely open them at full charge.
Lithium ion batteries are able to experience thermal runaway caused by internal shorts. This can be mitigated by quality control and proper handling (a lesson Samsung recently learned), and also other chemistries (like LiFePo, which is much more stable).
