Thoughts on battery and electrical location?

[J.P.M.]

Meaning higher pressure air coming in than the pressure leaving.

In a strict sense that's a correct no brainer but has nothing to do with design considerations for venting a space of certain gasses which have different densities relative to one another.

[Weldman]

Thats correct for propane. For Hydrogen, which rises, intake air at bottom, and exhaust out the top. It's a problem if you trap hydrogen in a confined space, or have an ignition source for it. And you need to be able to check water levels easily, and eventual replacements. Not an easy task

Meaning higher pressure air coming in than the pressure leaving.

[littleharbor]

I have a similar vent on a homebuilt camper I built. It is batteryless and only runs when the sun is shining. It has been running without a hitch for probably 10 years now

[J.P.M.]

Is the consensus that a reasonable quality and capacity roof vent similar to the one I linked would be a good venting solution?

Also assuming that I have a screened inlet for replacement air. Air in through the bottom and out through the roof.

Thank you Everyone for the input.

What happens when the battery dies ?

[PNW_Steve]

Is the consensus that a reasonable quality and capacity roof vent similar to the one I linked would be a good venting solution?

Also assuming that I have a screened inlet for replacement air. Air in through the bottom and out through the roof.

Thank you Everyone for the input.

[Mike90250]

High coming in and low going out on venting

Thats correct for propane. For Hydrogen, which rises, intake air at bottom, and exhaust out the top. It's a problem if you trap hydrogen in a confined space, or have an ignition source for it. And you need to be able to check water levels easily, and eventual replacements. Not an easy task

[Weldman]

Thanks for the input.

The vent fan that I linked was one that I stumbled onto and thought "this is a good idea". It does look low end. If it is a good idea I am sure that I can find a higher quality unit to get the job done.

I do not have any regulatory concerns. RVIA standards don't speak to battery venting.

More to follow. Have company.

High coming in and low going out on venting

[PNW_Steve]

On venting, among other things, make sure the air going out has a way to get in. Otherwise that stated 700 ft^3/hr. = ~ 11.7 CFM or so of what's probably an unrestricted flowrate number will quickly approach zero. Even then the flowrate will most likely be a lot less. Just screen the air inlet to help keep critters/unwelcome visitors out.

FWIW, that vent you show seems kind of chintzy to me. I note one review cautions the battery cannot be replaced. For as much air as that toy would blow, I'd wonder if a truly passive solution such as hi/lo top/bottom venting of the battery compartment with a short stack would move as much or at least a sufficient amount of air for the required duty but I'm ignorant as to the amount of air flow required for the application. In any event, I'd isolate the battery compartment from the interior of the bus.

Have you calc'd an estimate for the amount of air flow required for the application ? Any legal/code requirements for batteries mounted on/in RV's or conversions you're following*aware of ?

Thanks for the input.

The vent fan that I linked was one that I stumbled onto and thought "this is a good idea". It does look low end. If it is a good idea I am sure that I can find a higher quality unit to get the job done.

I do not have any regulatory concerns. RVIA standards don't speak to battery venting.

More to follow. Have company.

[J.P.M.]

I have been looking at passive solutions and stumbled across this solar vent that I could install on the roof.

https://www.ebay.com/p/1162592614?ii...8aAhGrEALw_wcB

On venting, among other things, make sure the air going out has a way to get in. Otherwise that stated 700 ft^3/hr. = ~ 11.7 CFM or so of what's probably an unrestricted flowrate number will quickly approach zero. Even then the flowrate will most likely be a lot less. Just screen the air inlet to help keep critters/unwelcome visitors out.

FWIW, that vent you show seems kind of chintzy to me. I note one review cautions the battery cannot be replaced. For as much air as that toy would blow, I'd wonder if a truly passive solution such as hi/lo top/bottom venting of the battery compartment with a short stack would move as much or at least a sufficient amount of air for the required duty but I'm ignorant as to the amount of air flow required for the application. In any event, I'd isolate the battery compartment from the interior of the bus.

Have you calc'd an estimate for the amount of air flow required for the application ? Any legal/code requirements for batteries mounted on/in RV's or conversions you're following*aware of ?

[PNW_Steve]

I have been looking at passive solutions and stumbled across this solar vent that I could install on the roof.

https://www.ebay.com/p/1162592614?iid=282829042544&chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&itemid=282829042544&targetid=859103850885&device=t&mktype=pla&googleloc=9033806&poi=&campaignid=6469981131&mkgroupid=88693113533&rlsatarget=aud-622524042718:pla-859103850885&abcId=1141176&merchantid=6510124&gclid=Cj0KCQiAsbrxBRDpARIsAAnnz_M0W-upGL1b6Uo5pfTDZDla_zjsqfatmUs8s9e3ptho_XW6yCWlkJ8aAhGrEALw_wcB

[PNW_Steve]

I saw a car battery explode in 1982. I don't care to see that again.

I have FLA batteries.

I am going to look at venting out the back. The back of the space is glass that is obscured by the insulation. I would have to take the glass and insulation out, cover the opening with 18ga. sheet metal, install the vent and then paint.

A possible option, I could run a vent from the battery compartment, through the engine compartment and exiting out of the back bumper.

I am just about clueless regarding battery venting batteries. I appreciate your help.


Edit: Duh! Hydrogen is lighter than air.... I have been looking at a vent in the bottom of the box like I did with my propane locker...

[Mike90250]

If you are venting a lead acid battery (flooded or AGM or gel) the vented fumes contain Hydrogen gas in explosive quantities, and acid mist, Flooded batteries produce both while charging, AGM & Gel only produce fumes when being overcharged or failing at end of life. Neither is good for breathing or electronics or engine compartments which contain electric starter motors or things that can ignite the hydrogen, It's rare, but it happens, and it's messy - with sulfuric acid sprayed everywhere.

[PNW_Steve]

Batteries should not vent into the engine compartment.
I guess this is an RV ?
if you can separate the battery venting from the charge controller thermal venting, that's best
Does the RV not have a factory load center ?

Thanks Mike.

I can partition the space into two separate spaces. One for the batteries and the other for the equipment. Each vented separately.

Venting the battery enclosure is a challenge. What do you see as the downside to venting into the engine compartment?

I don't know if any of this is relevant: it is a rear engine diesel RV. Right now it is an empty shell.. So far I have gutted the interior, raised the roof ten inches and sprayed foam insulation. I am working on the interior now.

[Mike90250]

Batteries should not vent into the engine compartment.
I guess this is an RV ?
if you can separate the battery venting from the charge controller thermal venting, that's best
Does the RV not have a factory load center ?

[PNW_Steve]

Another option may be to put it all under the bed.....

I will have a typical RV bed platform with storage underneath. It will be housing my 100 gallon freshwater tank but I may be able to fit both.