Dual Battery Location

[Papa]

I'm building a sleeping platform in the 2nd row seat area of our '10 Explorer and thought of locating an Optima battery and inverter there for auxiliary power. My reading about these batteries says there is no leakage or fumes. It would be in a fixed container or hold down. Am I correct that it would be safe to do this?

 

[theksmith]

I'm building a sleeping platform in the 2nd row seat area of our '10 Explorer and thought of locating an Optima battery and inverter there for auxiliary power. My reading about these batteries says there is no leakage or fumes. It would be in a fixed container or hold down. Am I correct that it would be safe to do this?

my understanding is that AGM style batteries do not off-gas except in extenuating circumstances - such as severe overcharging or if they are pierced.

i put mine in the old spare tire well in the rear of my Grand Cherokee. i got plenty of naysayers warning me not to do this though... so if i don't post back in a year, you'll know i done got blew up real good.

 

[PirateMcGee]

they make a pretty good hissing sound when they are venting...........you'll notice it

 

[theksmith]

from Optima's site:

Does an OPTIMA battery ever gas?

When used with a properly regulated constant voltage charging system (such as an alternator) the OPTIMA will usually not emit hydrogen gas. However, gassing can occur when charging at higher voltage levels or in extreme high temperature conditions. In automotive applications this typically will not happen if the alternator/regulator stay below 15 volts.

and from Odyssey battery:

It is imperative not to exceed 15.0V as this will cause the pressure valves to open and out-gas hydrogen, oxygen and water from inside the battery. This will shorten the life of the battery and cause premature failure.

so as i said - not normally

 

[Michael]

I also had the same concerns and agree with the previous comments -- Optimas shouldn't off-gas in normal situations, but may off-gas in extreme conditions such as when overcharged at high temps. As a former submarine sailor, I'm very careful with battery off-gassing. Fortunately, there is a very simple solution. The Optima D31T Yellow Top deep cycle battery serves well as an aux battery and also has a vent port on the top. Attach a piece of Tygon (or something like Tygon) tubing to the vent port and run it outside your truck. In the rare case the battery does off-gas, the gas will be vented to the outside atmosphere. Home Depot sells the right size tubing for a few cents per foot. You can just make out the vent port on this spec sheet from the Optima web site. Look on the back edge -- there is a gap with a round tube sticking out. I don't know if any other Optimas have this vent, but this one I'm sure of.

 

[OptimaJim]

Papa, you have been given very good advice regarding venting (which is refreshing to see). Even though our batteries and many others (both AGM & flooded) are considered “sealed” batteries, all lead-acid automotive batteries can vent gas in extreme situations. For that reason, we always recommend that any battery installed in an enclosed location be properly-vented to the outside. In addition to the Group 31 battery Michael mentioned, our group 27, 51, 34C, and 78 batteries all have ports for connecting a vent hose, although you'll probably want to stick with either a Group 27 or Group 31 battery for your application. Although people do it anyway, we would never recommend installing an unvented battery in any enclosed space, because there's a legitimate, albeit unlikely, safety risk involved.

For example, IF there is a voltage regulator failure, and IF the battery is severely overcharged, and IF this goes unnoticed, and IF the battery vents because the internal pressure exceeds the release pressure of the vents, the gasses are both flammable and toxic. This may sound like a lot of “ifs,” but attorneys and engineers get paid to plan for every worst-case scenario. If anyone has any questions about our batteries, I'll do my best to answer them.

Jim McIlvaine
eCare Manager, OPTIMA Batteries, Inc.
www.facebook.com/optimabatteries

 

[Scott B.]

Papa,

Thanks for asking the question - I was just about to ask the same one!

Jim - thanks for the response. I will be mounting my YellowTop under the sleeping platform in my Ranger, with a vent tube going outside.

Any problems with venting under the truck bed? (Accumulation of hydrogen gas, etc.)

 

[Mike S]

I have mounted 2 banks of (2) AGM 6V golf cart batteries in my Airstream - under the bunks. There is little chance of off-gassing if the balance of your electrical system is up to snuff. I should note that I dumped the factory converter and installed a converter with sensor and multi-stage charging. I have used the trailer for 60 days at a time with no problems either charging from shore power of my Honda generator.