External Battery Vent

[emm-dee]

When doing a periodic walk-around check of my Vengeance TT yesterday I found the battery box (on the trailer tongue) had about ¾ inch of water in the bottom. Solved that problem by drilling holes in the bottom of the box to allow draining.

The water probably entered via the two small slotted vent holes on the top of the battery box cover. I'm aware the battery needs ventilation but isn't there sufficient ventilation provided by the downward facing openings (in the top) where the cables are routed? Any one of these four openings provides triple or more intake space than the little slotted areas on top of the box. The only difference I see (other than the larger intake area) is the cable outlets face downward but the vent slots face upwards.

On my horse trailer both of the 12vdc batteries do not have vent holes on the top...only similar holes where the cables enter the box.

The question for the battery experts here is will there be any problems created by closing off the vent holes on top of the battery (which would solve the water intake problem).

[Kaadk]

Not a battery expert, but I believe the vent holes are on top because the gasses from the battery are lighter than air and therefore would only escape from the lid if they were able to rise. The only way they could escape from the downward facing openings is only after they filled the lid. (Hope that makes sense.)

[boondocking]

I have no vents holes on my battery box except for the small cable holes and have never had a problem over the years.
I think you will be OK closing up the upward facing slots.