2 pints of water found in 12 battery bay when changing 7 year old battery

Was really annoyed to find almost 2 pints of water in the 12 battery bay when I went to remove the faulty original battery ie clear liquid level almost encroaching on the base of the battery itself which is elevated slightly by a small stand support - thought as first it might be acid from failing 12 battery but a quick test with blue paper saw no change in color & there was no sign of acid erosion on the mastic seals however some small brown smears after being dried out turned out be carpet fluff & the liquid was really water - phew !. & there are no signs of water seepage from above the area in question.

My question is could this be a long term effect of condensation from the powertrain black plastic ventalation conduit that runs to the rubber vent flaps on the outer right hand side of the chassis next to the battery ? - was also suprised to find that the conduit chassis hole is very much larger than the conduit coupling face itself AND the conduit has a large hole ( by design ) on its underside very near where it snakes past the positive terminal on the battery clearly allowing air from the powertrain module to circulate in the lower boot compartment as well as the chassis vent flaps to do so as well - so I am confused as to why this is so ( I always thought a conduit was meant to take air from A to B withought massive holes in the general design ? ).

 

Thankyou - will go over everything tomorrow to find any suspicious looking seals etc, only had the car 6 months so I am a newby - only other fault is proximity rear sensor beeping no longer works which to me is brilliant as it was very annoying ( reverse beep still works ) - both of which I can do without anyway ( reverse parking still works without the proximity audio beeper - hell I dont need it it as it is quicker to park myself lol ).