Battery Box Ventilation

[P69]

Where does one strike a balance between ventilation of heat/hydrogen gas from battery boxes and containing any acid leaks inside the box?

I made the new battery boxes (https://pearson365.com/forum/index.php?topic=2134.0) and they are pretty sealed up for now. I need to consider ventilation to carry out heat from charging (how much head is created during charging?) and to dissipate hydrogen gas so it does not accumulation inside the boxes.

I guess I have to figure out the chances of a knock down severe/long enough for fluid to leak vs. the need to vent hydrogen gas and heat.

Anyone have any advice battery box ventilation?

[SVJourney]

Hydrogen gas is the lightest gas there is.  It rises very fast and dissipates.  Explosive concentrations are fairly high.
Normal venting is one half inch hole near or on each side of the lid of each box.  Since your box has multiple batteries I would go a bit more, but your wire through hole provides a good bit of it.

[Dale Tanski]

Or...
AGM batteries which are sealed and have internal pressure compensation bladders that deal with expansion from the heat generated while charging.  Also I would recommend a temp sensor on your batteries to tell your smart regulator to back off on the rate so as not to cook them.

Dale

[P69]

I might go with AGMs in the future, but for now I have these flooded golf cart batteries.

Dale, with a temp sensor, there is not worry about heat build up because the charger will detect the temp and crank charging rate down accordingly? If my understanding is correct, I just have to deal with hydrogen gas because i already have a temp sensor attached (the small wire on the last negative terminal).  Maybe I'll put a hole in opposite side  for cross vent. 

Thanks y'all
.

[Dale Tanski]

With a temp sensor there would not be a worry about heat build up in terms of damaging the battery, as the voltage regulator will throttle back the amount of charge.  The heat will still have to be removed from around the battery or the sensor will show a false narrative and you will not charge at the highest rate available due to the heat issue.

Dale