Large batteries under rig?

[Naio]

I have 4 of the 100+ lb AGM batteries that MrWizard has, and I want to place them under my new (used) van, on brackets attached to the frame.

I can't afford the Tork Lift Hidden Power (cost is double or triple the cost of the batteries) and am looking at DIY options.

I'm looking at various heavy duty brackets, will try to find a cheap welder, etc. But I thought I should talk to you guys, too.

If I use brackets, I am thinking to make shelves of exterior plywood to spread the weight, with 2 or more brackets per battery bolted to the van frame. I would add nylon ratchet straps around frame+battery just so they won't bounce off.

I'd prefer bolt on even if I get a welder to make shelves. Is it a bad idea to put all those bolt holes in my frame?

What do you think of these brackets?

Simpson, for concrete forms. Nice cheap option but unsure of weight rating and could only use 2 per battery:

L-shape, for kitchen countertops:

Z shape, sellers says in the Q&A they are 50lbs each, I could use like 4 per battery:

Another L shape, also seller says 50lb, less expensive:

Do you folks have any other great ideas?

[kerrlakeRoo]

My experience is more with boats. But I know 200 lbs being jarred becomes massively stressful on welds alone. If your floor is corrugated metal, you likely have about 1 1/2" flat sections, a piece of 3/16 steel or even a large washer will go far to spread the stress. The rack shown in the response above is an example, 4 1/2" bolts going up from the bottom through the deck should be sufficient. If you want to go to 6 hanger bolts you could avoid welding to your frame, then like rjxj said , you could in the future drop the whole thing with a floor jack.
Happy motoring

[Naio]

kerrlakeroo, you're saying add some bolts up through the floor? Not a bad idea, tho they would need to go through a heavy steel plate on top of the floor.

(My current, indoor, setup is like that -- I have tiedowns that go through the floor and through a plate.

[MrWizard]

how ever it gets built
remember the most force will come when hitting the brakes
the most shock from bumps and pot holes
i would make the front/forward side and rear facing sides, closed steel sides
loading and straping from the outside aka left or right,

just something to consider

[azrving]

You need to build something out of steel and bolt it to a solid area. The side plates can be removed to get these 6 volts out or I can remove the bolts at the frame and lower it with a floor jack. There is enough room to use a mirror when watering these. You have more flexibility when using agm. Depending on what road conditions you expose the batteries to you may want to grease all the terminals well and put a rubber cover on top. A sheet of rubber would help keep wet conductive dirt off the tops.

[kerrlakeRoo]

Naio, I agree with the others on hiring a welder, but I would also add a couple of tabs Through bolted to somewhere inside. Suspending two 200+ or a single 400+ lb rack from the underside is a lot of pressure and your counting on frame sections being strong enough and on the welds all being good enough. When you hit a pothole the short force will be triple the actual weight. Simply having a couple of through bolts with large washers above will be some added security.

[RoyB]

Too bad you can't rig up a pull out very heavy duty roller bearing tray of some sort... I would want to have a way to do my simple battery maintenance things...

On my off-road trailer being so high off the ground I even thought about a trap door inside one of floor cabinets to get to a battery bank mounted under the floor...

Roy Ken

[pianotuna]

Naio,

Only the iron shelf brackets are thick enough to take the sort of pounding they will be subject to.

A welder will create something much better than any of the four you found.

[pianotuna]

Hie thee to a welder. Take their advice. Tie down straps are a must. DAMHIK.

I'd use a 1/2 to 3/4 inch plywood floor in a "well" of angle iron to spread the weight over the entire side of the battery (I have the same as you and Mr W).

Do adjust the float voltage to what your particular iteration of the jars requires. Do use temperature compensation charging if it is available.

[Naio]

Thanks, guys!

Landy, I like the idea of an access hatch. I know other guys here have told me if I put in a proper panel I will never need to access the terminals, but, well, I am not that trusting :).

I was thinking to put them on their sides for access, if no hatch. And if course to put 2 on each side of the rig, as far forward as practical. They'll be behind the front seats.

I was planning to put them on the outside of the frame, which means the frame will be between them and the exhaust system. Cooler, but more vulnerable in a crash. This is where standard/aftermarket smaller batteries go. What do you think?

[landyacht318]

I can fit 2 flooded group 27s in my under body battery box, longways, but might have to modify the handles somewhat to fit.
I have an acess hatch to get at them from above.

Mine was made from the garage door angle iron which has all the holes predrilled in them. I was originally planning on attaching some sort of retail tray and fasteners to frame, but my friend with the welder said we can make it for a fraction of the price with materials he had laying around, and weld it to the Van instead of bolting it.

I think since you require a welder anyway, well most welders also can fabricate everything and might prefer to do that rather than trying to weld in something prepainted or which was designed to be bolted.

The fabrication of everything route opens up more options in terms of mounting and location, in my opinion. With 4 of those batteries you might want 2 on each side to even out the weight distribution.

I'd find the welder first, ask their opinion on mounting your AGMS on their sides for minimal ground clearance loss. Let they think about the design they would like to make. Do have them consider rocks lifted up and thrown by the front tires, and perhaps rear tires if one is trying to back up in gravel up a hill.

One thing my thermocouple indicated to me when I installed it on my underbody battery is just how much engine heat goes under the van body when moving. Not sure what can realistically be done. I incorporated a heat shield as the exhaust pipe was 18 or so inches away, but the readings I got when driving were quite high, and dropped quickly when stopped. Prolonged driving could bake the batteries, and if high amp recharging via alternator could have them hotter than they would like to be

[Trackrig]

Go to a welding shop, they'll fabricate something out of angle iron.

Bill