Questions about where to place AGM house battery

[Smoky]

I’m currently making plans to turn my truck cap into a camper with a dual-battery setup with both batteries under the hood. The battery of choice for house batteries seems to be AGM. That said, there seems to be quite a bit of debate about where to safely mount AGM batteries – in the engine compartment or inside the camper (though there are other locations). Placing inside somewhere brings up the issue of off-gassing. There are highly reliable sources indicating that AGM batteries will give off hydrogen if overcharged, but that such venting isn’t a danger if the area they’re located in gets reasonable ventilation. I’m still debating about the venting issue but am feeling better about potentially placing the house AGM in the truck shell since it’s not a sealed environment.

What I’m looking at now are reports that AGM batteries shouldn’t me mounted in an engine compartment because they are more sensitive to heat than lead core batteries, and the increased heat under the hood can significantly shorten their life. How true is this, and how much would their life be shortened? Also, can placing an AGM battery in the engine compartment do other damage to the battery besides shortening its life?

Thanks, in advance, for your perspectives.

 

[DiploStrat]

More free advice:

-- There are many good sources for AGM batteries. I use Lifeline and they have been excellent. More to the point, the post excellent technical information and will answer e-mails.

-- My four Lifelines are hung under the camper attached to the camper sub-frame. You could do the same thing, attaching to the truck bed.

-- If you overcharge an AGM to the point that the vents pop open, you are going to replace the battery as, being effectively sealed, you cannot replace the lost moisture. Use proper chargers, like your Chevrolet and a good solar or shore charger, and you will never overcharge your batteries.

 

[Smoky]

DiploStrat...thanks for the info. Monday night, I ordered the VMAX MR127-100 Deep Cycle battery you called my attention to...got it at the sale price plus another discount since it was my first order from VMAX. The sale ended Tuesday.

I'll explore under-frame mounting options but I want avoid areas where the battery could be damaged by something i run over (I plan to do some 4-wheeling). Are you suggesting the engine compartment is a bad mounting location due to heat?

 

[DiploStrat]

Heat is an issue, but you already have one AGM battery there. I, too, spend time off pavement and my batteries are well out of the way. (Side mounted.)

I am only pushing you, mildly, towards two batteries as they will last so much longer than one and give you a lot more reserve.

 

[Smoky]

Hoe do you protect your bats from water and dust without placing them in a sealed enclosure?

 

[DiploStrat]

I don't, beyond a plastic splash shield.