I'm considering replacing my lead acid starting batteries on my boat with something like this. 500F @ 16v Starting battery module
https://www.maxwell.com/images/documents/ESM_Manual_Install_4_15.pdf
I understand the high current risks associated with capacitors vs batteries. I had an older 12v 8d battery explode on the boat, my guess is that it was off gassing due to age and condition and the off gassing ignited.
I have seen what happens when a lead acid battery explodes, and the gas / acid is bad. What kind of gases/explosion/fire from a capacitor?
Best Answer
It's pretty much the same, the explosion is faster because as soon as there is an internal short all the energy in the capacitor is dissipated into heat almost instantly. As far as gasses go, it depends on the electrolyte, and usually it's hydrogen. If the dielectric starts on fire, the smoke could be toxic.
Capacitors don't have near the storage capacity that batteries have and most capacitors leak current faster than batteries.