Ventilation requirements for batteries

[DannyLori]

I recently relocated my three 12 volt deep cycle marine batteries to an enclosed storage bin in my 5th wheel. They are connected in parallel and I am wondering if the storage bin needs to be ventilated?

[NMWildcat]

Yes!

[bikendan]

Originally Posted by DannyLori

I recently relocated my three 12 volt deep cycle marine batteries to an enclosed storage bin in my 5th wheel. They are connected in parallel and I am wondering if the storage bin needs to be ventilated?

Yes, since they are lead acid batteries.

[Oaklevel]

YES !!!!!!!!!!

[NavyLCDR]

Well, that depends on if you were hoping on making a homemade Hydrogen Fuel Cell. If not, then yes, the space needs to be ventilated (lead acid wet batteries). They can vent considerable amounts of Hydrogen gas.

AGM batteries do not need to be in a ventilated space, but they do have ports that you need to attach tubes to and run the tubes to outside air.

Lithium batteries need no ventilation.

[NavyLCDR]

Here is an SDS for lead-acid batteries notice precautionary statements P271 and P403:
https://www.usbattery.com/wp-content...020.01.092.pdf

P271 Use only outdoors or in a well-ventilated area.
P403 Store in a well-ventilated place.

[TitanMike]

Yes on venting. In addition it's highly recommended that batteries be in some form of containment like a battery box.

Even if just a "box bottom" unless you don't mind corrosive liquid possibly eating through your compartment's floor.

[jay2703]

If they are that bad, why did my '66 VW Bug have its battery under the back seat cushion?

[nvs4602]

Originally Posted by jay2703

If they are that bad, why did my '66 VW Bug have its battery under the back seat cushion?

To make the floor pan rust out quicker.

[NavyLCDR]

Originally Posted by nvs4602

To make the floor pan rust out quicker.

[Sleepy]

I have a VW Touareg TDI and the battery is underneath the drivers seat. Not a "bug", but VW has been doing this for many decades.

[Reverse_snowbird]

You'd be safer with an AGM, Gel Cell or Lithium-Ion which don't need venting. If you don't vent those properly, you risk an explosion and while that may be an acceptable risk in some cars, it's not a risk you should take in your rig.

[mnoland30]

The hydrogen that vents from your batteries can ignite with any spark. Google boat vents for ideas on how to vent.

X2 on having a rubber or plastic tray under the batteries to catch the acid that can boil out of a battery during charging. I couldn't tell if your second picture was a box or just a cover.

It is a good idea to have the batteries strapped down. Picture hitting an unexpected bump at highway speed and your batteries bouncing around and spilling acid. I expect it is probably required by law, I know it is for boats. I made mine with a 1" nylon strap and a no sew fastlock buckle.

[markb422]

How old are the batteries? If they are needing replacing soon, you could opt to buy AGM SLA batteries. A bit more money than marine/rv batteries but do not need you to cut vent holes in your compartment doors and floors. Also, if you buy good deep cycle batteries you could probably eliminate one battery and go with two. For tie downs, I have used all thread rod with black rubber bungies. I removed the hooks from the bungy straps and run the all thread through the holes. I run the threaded rod down through the floor. Nuts on the ends for adjusting tension.

[TitanMike]

Originally Posted by Sleepy

I have a VW Touareg TDI and the battery is underneath the drivers seat. Not a "bug", but VW has been doing this for many decades.

Yes, it is under the seat. It also has a vent tube/hose that routes any hydrogen or electrolyte outside the vehicle.

BMW and Audi do the same with the batteries mounted inside the passenger space.

[D W]

Originally Posted by TitanMike

Yes, it is under the seat. It also has a vent tube/hose that routes any hydrogen or electrolyte outside the vehicle.

BMW and Audi do the same with the batteries mounted inside the passenger space.

X2. Many GM autos are configured the same way.

[DannyLori]

Lots of great advise Thank you, I appreciate all your responses. My batteries are less than a year old. I am going to install a rubber mat under the batteries and install a vent on the front of the black panel I will also install a vent on the door of the bin and run the original ventilation hose from the old location into the new location. Hopefully this will allow adequate ventilation. I am also going to strap the batteries to the floor of the bin.

[DannyLori]

[DannyLori]

[NavyLCDR]

It is a myth that AGM do not require venting. They do require venting, but unlike wet lead-acid batteries, AGM can be vented via a tube connected to the vent port on the battery and routed to outside air.