2nd Battery Location - Under hood or in bed?

[Scott B.]

As the title states, where is the better/preferred location to mount a second battery?

The vehicle in question is a Tacoma, with a shell on the back. While I do pull a teardrop, there will be times when I will sleep in the back of the truck.

I would prefer the battery in the back for better weight distribution. However, I wonder about the safety/sanity of sleeping on top of a battery.

Thoughts and suggestions?

 

[AndrewDM]

I prefer under the hood, less cable to run than in the bed. My brother did put his in the bed of his Tacoma, very clean installation and with camper shell as well.

-Andy

 

[NikonRon]

I have mine in the bed with a camper shell, it is an AGM. Never really concerned me sleeping in there with it. Ron

 

[DiploStrat]

Charge or Discharge?

Bit of a wash.

-- Under the hood: May have a nice mounting tray available. Can use shorter/smaller wires to the alternator. Must use longer/bigger wires to the load(s). Got a microwave? You probably want your batteries as close as possible to the inverter. Only got a bunch of LED lights? No real load to worry about.

-- In the back: Probably have to think about venting, even with an AGM. Got to use larger/longer cables to get a charge from the alternator, but wiring up your loads will be easier.

You can make either work well.

 

[Scott B.]

The venting issue is the one I am most concerned with.

About a year ago, one day on the trail, an AGM battery went bad (had an internal short.) The battery got very hot, and out-gassed - a lot. It was under the hood, but still a pain to deal with. If one failed in the bed, under my sleeping platform, that would be a pain the butt to deal with.

However, that was the only battery that I've had that went bad, so I am not expecting a repeat performance.

 

[4x4junkie]

It likely outgassed because it's 5 remaining good cells were being incredibly overcharged because of the one shorted cell.

Gassing like that is far less likely if the engine is not running (such as while you are in the back).

What DiploStrat said is spot-on. Either way has advantages & disadvantages. Whichever one suits you best, pick that and go with it.

 

[ohv]

What do your frame rails under the bed look like? Creative fabworks has one for the dodge 2500s which I've been looking at, poly performance has a universal kit as well.

 

[Scott B.]

What do your frame rails under the bed look like? Creative fabworks has one for the dodge 2500s which I've been looking at, poly performance has a universal kit as well.

I'm a little leary about putting the battery under the bed. I worry about water and mud - and if anything is behind the tires, it will get sandblasted.

 

[Scott B.]

It likely outgassed because it's 5 remaining good cells were being incredibly overcharged because of the one shorted cell.

Gassing like that is far less likely if the engine is not running (such as while you are in the back).

What DiploStrat said is spot-on. Either way has advantages & disadvantages. Whichever one suits you best, pick that and go with it.

I'm not too worried about another shorted cell - hopefully, that was my "once in a lifetime".

In my Ranger, I have a battery in the bed. The cables (4 ga. marine) aren't too long, and are fused at each end. The setup works well, and I like keeping weight off the front end.

Maybe I should think about building a sealed and vented compartment in the bed for the battery...

 

[rayra]

There are several models of battery box available to shelter both the battery and anything around it. But if you have room under the hood I'd think that would be best just to save the cubic space in the cargo area.

 

[WSS]

If you keep them together, you have the advantage of 24v for welding. Mine has the outside (closest to fender) hinged for quick removal for portable 12v power or a quick jump that I cannot reach with cables alone. Also has a isolator and 200amp relay to self jump if the main goes dead, just flip a switch on the dash panel and the aux batt kicks in. Great for hard winching too. Last pic shows mig welder (readywelder brand) and the 24 yolk adapter using Anderson connectors (yellow and red quick connects)

 

[rayra]

That's a VERY nice setup WSS

 

[WSS]

That's a VERY nice setup WSS

Thank-you!, it has been in for about three years and has worked great out here in the so-cal mountains and deserts. Top of the list for welding repairs has been steering rods that kink, cut out the bad section and splint it with a piece of angle iron or even tube if you have the right size.

WSS