@syseng68k
In this case, I wonder if the so called fan in that enclosure is there for cooling, or primarily to exhaust the corrosive gases ?.
Cooling, one would not want to exhaust alkaline gases into an alu fuselage.
As to the gases, like with Pb, it's primarily hydrogen/oxygen, which this poster learned in his early teens, when a car battery blew up in his night desk after being _accidentally_ shorted. (head light makes a good reading lamp).
Electronics and cells of any type don't mix and just because it's common practice, doesn't mean that it's correct, nor that it isn't just wrong by design
. Everyone else does it, so it must be ok, right ?.
Engineering practice generally has a sound basis. For example, practically every modern LiPo battery has electronics for balancing integrated.
Designers must question everything, especially their own assumptions and those of the people they most respect...
Right, against convenience, one should not make assumptions at all, because assumption is the mother of _all_ failure.
See, think, validate goes both ways. We have still not seen all the facts and can not make assumptions on changes before understanding the cause.