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can the second OEM battery be separated?

5404 Views 12 Replies 6 Participants Last post by  Radioman
has anyone with the two battery setup from ford looked at how difficult it would be to install a cutoff relay between them, in order to isolate the second battery as a true "house battery"? is there room in the compartment?

further, could the wiring for the upfitter switches and customer convenience circuits (and perhaps some of the van's other "house"-like circuits) be moved onto that battery? perhaps the bus they're connected to could be physically severed? this would almost certainly be a lot harder than separating the batteries and running the "house" battery to a new panel.

think of this as idle brainstorming -- it just seems a shame (for my uses) to "waste" that battery if i install a separate house system, so i'm leaning strongly toward not ordering the dual battery option.

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I'll give your questions a shot.

You want the dual batteries as you get the 220 amp alternator. Which you'll need on some house batteries.

Can you separate the two batteries, sure. I think that would be foolish. You're only getting 2 -- 75 amh batteries. Having only one would be a little risky. I think it would be easy to run down.

I think you'd also have to introduce technology to make that work; like your big relay and some sort of sensor/switch to activate it. Cause you'd still have to use the alternator to charge the second battery. I'd use that money to buy more batteries and some sort of charger, whether it's a stepped charger from 12 volts or ran from an inverter.

As far as running the upfitter switches from the house batteries; I think that would be relatively easy to do, though my approach to wiring is a bit untraditional. The fuse block has a few extra spots to tap or to feed from the second battery. You'd have to unplug the various supply lines (to the upfitter switches and to the accompanying relays) and insert the house line. You could put in another fuse block if monkeying with the OEM block is daunting. You'd still use the factory lines, just plugged into another fuse block. The wiring would be a little tight if you tried to do all that without extending the factory lines. And again, it would appear to be foolish. You'd be so close to another separate system -- with your own fuse panel and a few switches that could mounted anywhere.

I have a combined 400 amh and am going to expand that to 800 when I add the solar cell.
Good luck it is a fun process.
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Aren't they two separate options?
Could be. I was thinking that came as a package.
longboard -- i just noticed (in the PIB brocure) that the diesel includes the dual batteries, and remembered your comment. why does the diesel require more battery? is that just a "diesel thing"?
Compression. Diesels have significantly higher compression ratios.
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