Max Amp Hours you can fit in a Slee 2nd Battery Mount? (1 Viewer)

mdcoa

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I just did a search for "deep cycle" and read about 10 threads on batteries and 2nd batteries, but couldn't find what I'm looking for, so I'll go ahead and take the plunge and start a thread.

I run a 2nd battery in a Slee mount monitored and charged with a REDARC BCDC unit. I'm currently running a Group 22 60 AH AGM wheelchair battery, and would like something bigger--my fridge recently ran this down to about 50% (12V) in about 15 hours of sitting in mild weather.

The current Group 22 battery doesn't take up all the space in the Slee mount--length is about at max, but I could probably go another 1" of height (9") and another 1.5" of depth (7" vs. 5.5").

Definitely want a true deep-cycle, as I only use this battery for low-amp applications (e-locker relay, fridge, USB chargers, etc), but haven't yet found anything with more than 60AH that'll fit. Anyone have any secrets?

Alternatively, I can slap a 100A flexible solar panel on the car top carrier and run that to the REDARC, which would probably give me more time between charges required. . . I'll do that if 60AH is the best I'm going to be able to do.
 

saucebox

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In for answers, as I'm in the same position.

I did add a 100W flexible solar panel though, and it's met my needs everywhere except the coastal PNW. Especially here in our desert summers, the panel creates more energy than the fridge takes out.
 

hoser

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You can also consider a LiFeP04 battery... which can safely discharged to 20%. So more usable capacity (and lighter in weight)... but also more pricey and you they don’t like high temperatures... and so that has to be addressed.
 

mdcoa

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You can also consider a LiFeP04 battery... which can safely discharged to 20%. So more usable capacity (and lighter in weight)... but also more pricey and you they don’t like high temperatures... and so that has to be addressed.

Yup, those are so awesome, but would require me finding a spot inside the vehicle, which I cannot do for a family of five contemplating a year-long trip—aieeee!
 
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I had a X2Power brand Group 27F AGM (92 AH) on a modified Slee 2nd battery tray. The guy I bought my Cruiser from did it. He added plywood on the base to make it flat across. With that layout can fit the 27F on its side. AGMs can be mounted sideways.

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mdcoa

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I had a X2Power brand Group 27F AGM (92 AH) on a modified Slee 2nd battery tray. The guy I bought my Cruiser from did it. He added plywood on the base to make it flat across. With that layout can fit the 27F on its side. AGMs can be mounted sideways.

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Thanks! Looks like that's either an earlier version of the Slee mount, or he cut out the section between the compressor mount and the rest of the mount. Having just mounted a compressor on mine, I'd like to keep it, but could perhaps move it somewhere else more easily than I can find another battery . . .
Found this deep cycle on Home Depot, which would be a 25% capacity increase and maybe would squeeze in--I need to dig out the tape measure and see . . .

Or this fella, which is even closer to the length I think would work, but maybe on the tall side . . .
Amazon product
 

mdcoa

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Thanks for the feedback, folks! Glad to hear a group 35 fits.

Anyone know of a Group 75 or 35 true deep cycle (vice "does it all")? I haven't been able to find one, and am beginning to wonder if the battery group construct is only used for starter batteries, with deep cycles (for one's unabomber shack or sailboat) being not-so-much categorized by size.

Also re. the Lithium Ion batteries, since they need to be out of the engine compartment, I sure wish someone made a flat one that'd fit under a front seat, like 1x14x18 or something . . . that would be killer for folks who don't want to devote a battery-sized chunk of their interior to energy storage. . .
 
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Thanks for the feedback, folks! Glad to hear a group 35 fits.

Anyone know of a Group 75 or 35 true deep cycle (vice "does it all")? I haven't been able to find one, and am beginning to wonder if the battery group construct is only used for starter batteries, with deep cycles (for one's unabomber shack or sailboat) being not-so-much categorized by size.

Also re. the Lithium Ion batteries, since they need to be out of the engine compartment, I sure wish someone made a flat one that'd fit under a front seat, like 1x14x18 or something . . . that would be killer for folks who don't want to devote a battery-sized chunk of their interior to energy storage. . .
I just replaced the factory amp under the passenger seat and there's a ton of room under there. I wonder if its the same on the driver side? If it is then you have 2-3" probably.
 

mdcoa

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Resurrecting my own thread, since I've been re-pondering.

Does look like a 75Ah battery would fit pretty well--they're 10.25" long, which I think might _just_ squeeze into the Slee tray:

Amazon product
But what I really wonder is if I cut both of the end tabs off of the Slee tray, could I fit a 100AH battery in there? Like this, which is 12Lx6Wx8H . . .

Amazon product
75AH is probably my plan, since I'm 100% sure it'd fit with, at most, minor mods . . . but maybe I'll pull my battery and do some measurements and see if I could squeeze 100Ah in there--that'd be a game-changer.
 
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I just replaced the factory amp under the passenger seat and there's a ton of room under there. I wonder if its the same on the driver side? If it is then you have 2-3" probably.

My 2004 driver seat is pulled underneath by the rear AC intake I believe. There is zero room under it
 
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Following this thread to see what you come up with. Hoping to figure out a way to run my 65L for ~48 hours without having to run solar, but I’m thinking that’s not realistic unless I run lithium in the truck.
 

mdcoa

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Following this thread to see what you come up with. Hoping to figure out a way to run my 65L for ~48 hours without having to run solar, but I’m thinking that’s not realistic unless I run lithium in the truck.
Yeah, that's probably a tall order unless you can start the engine at some point and recharge, even with a 100Ah battery. Any idea how many amps your fridge typically draws? Do you have an insulated cover for it? And are you talking 48 hours in Arizona or Newfoundland? Either way, 48 hours of operation even at relatively low draw is a lot to ask.

I have no idea of the science involved, but it'd be nice if someone made lithium battery that's maybe 12x12x1" that could go under seats. Or a bigger version of that that you could stick under the carpet in the cargo area. . . would sure be nice not to have to devote a big cube of interior space to a lithium battery. That's why I like the under-hood placement--costs me 0 space I'd otherwise use for gear. But obviously too hot for lithium. . .

(just realized I said this already in this thread . . . )

I'll try to pull my second battery in the next couple days and do some pondering and measuring--will post results here.
 
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Thanks! 48 hours is definitely a worst case scenario as I'm rarely stationary for that long, but it's a nice goal. Fridge is still sitting in the closet, so I don't really have a gauge for its draw yet. I have a buddy that's setup with 180Ah of lithium in the bed of his fullsize and it always makes me jealous haha.
 

mdcoa

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Well, I just measured my Slee tray tonight--it's about 9.25 long and 7.5" wide, so no way i can cram even a 75AH battery in there. And because the inboard end of the mount is partly the bracket for the PS reservoir repositioning, it cannot just be cut off. Unless I want to jettison my compressor and mimic @CORunner 's setup, I reckon I just need to figure out how to live with 60AH of storage. Perhaps grab some solar panels . . .
 

hoser

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Maybe not the answer you want but you can also rewire it... make the 60AH battery your starting battery and one near the headlamp the 100AH aux battery.

And also, a more expensive option but a group 31 battery also fits in front of an OEM cyclonic airbox. With this mod, you can actually fit three batteries under the hood of a non-AHC 100.

 
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mdcoa

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Maybe not the answer you want but you can also rewire it... make the 60AH battery your starting battery and one near the headlamp the 100AH aux battery.

And also, a more expensive option but a group 31 battery also fits in front of an OEM cyclonic airbox. With this mod, you can actually fit three batteries under the hood of a non-AHC 100.

Great idea, thanks! Hard to tell for sure in that thread on the cyclonic filters, but it doesn’t look like there’s gobs of room between them and the AHC reservoir, which has may mean one wouldn’t fit in front of the Slee 2nd battery/ compressor mount, which I think extends pretty far forward of the AHC reservoir.

but you’ve got me wondering how many amp hours I can cram in front of the stock NAS air filter housing—there might be room for 10 or 20....I’ll get out there with a tape measure tomorrow....and this also has me thinking of the space where the charcoal canister is on early 100s—I’ve got an six fuse panel there but some space under it...thanks again.
 

mdcoa

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Following up with a mad brainstorm, linked to the epiphany above (putting a small deep cycle battery between the air cleaner and the passenger side headlight):

What about _four_ of these 22 AH batteries--three will fit in the Slee mount, and one could go in front of the air filter. Not aware of any other way I'd fit 88 AH of storage in there. . .
 
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I think i've come to the conclusion I'm going to run a LiFEPO4 in the back. Sucks to have the system take up space, but keeps weight off the already heavy nose and probably the only way to get the usable 80 Ah I'm looking for. Two 50 Ah batteries can be tucked away pretty well near the wheel arches.
 

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