I've seen enough batteries blow up/vent gasses/spray acid all over everything, that when I do my EV I'll definitely seal any battery chamber in the car, and vent the chamber to the outside.
I once had a lawn/garden battery I was charging spray me in the face good when I pulled a cap to check acid levels - the vent tube was blocked!
I was really glad that I wore glasses!
...sure cleaned 'em up good...
