I'll be able to make a mount right up against the inner sheet metal, that will place the battery even with the top of the wheel tub. In that spot, the width of the H8 battery will not extend past the edge of the rear hatch. I'll see if I can post some pics of what my bare cargo area looks like right now. The plastics that make the back pretty definitely suck up quite a bit of real estate.
Realistic Expectations of Solar/Fridge Setup
- Thread starter jimbono
- Start date
Good to know. I think I might take a look on the left side near the 12v outlet, a small shelf and a top to keep the posts clear might work just fine. I’d probably trim the plastic and leave as much as I can just for a clean look though.
I looked under the jeep today, I think I may be able to make a hanging mount that fits a battery inside the spare tire, I’d have to see how big the space really is but that might work nicely. I could definitely fit a battery above the exhaust but there really isn’t a way to get it in there. The spot in front of the gas tank looks like Itd be an easy spot to drag for me. I noticed a gap in front of the rear axle on the passenger side of the parking brake cables that might work, but I’m not sure where I would mount something to hold a 50-70 lb battery and stay out of the axles flex.
Another possible spot is up front opposite the washer fluid reservoir, I might be able to fit a smaller battery there and wire another under the stock battery in parallel. Simple is good to me though so maybe the inside is a better option. I wish that evap canister wasn’t there!
DiploStrat
Expedition Leader
Listen to Jon (luthj) - he knows of what he speaks. Listen to the folks who are actually making things work in the real world.
Bad idea. You want real, deep cycle batteries to keep your beer cold. You can always use a deep cycle battery to help your starter battery, should you do a poor job of designing your system, but you cannot use a starter battery to keep your beer cold. OK, you can, but it will not work as well or last as long.
If you REALLY must go with a single battery type, then replace your starter battery with a deep cycle and add more of the same deep cycle, see slides 8 and 9 here: https://cookfb.files.wordpress.com/2016/09/dual-battery-slides-2016.pdf
Some of us have been doing this for years and have cold beer and hot espresso every night. It is not hard to design a proper battery system for your camper, but you have to do it right. Worrying about flatting the camper battery or needing to self-jump indicate that you have a poorly designed system.
A Jeep Cherokee is a small vehicle for roof and weight, but as long as you pay attention to the numbers, you can make it work.
Partian Shot: 100w will only produce about 5A under perfect conditions, and, as conditions are rarely perfect, 200w of solar is a good minimum.
I just like the redundancy of the house and the starter being the same. Plus... I've made it the same for all in my herd of piles.
Bad idea. You want real, deep cycle batteries to keep your beer cold. You can always use a deep cycle battery to help your starter battery, should you do a poor job of designing your system, but you cannot use a starter battery to keep your beer cold. OK, you can, but it will not work as well or last as long.
If you REALLY must go with a single battery type, then replace your starter battery with a deep cycle and add more of the same deep cycle, see slides 8 and 9 here: https://cookfb.files.wordpress.com/2016/09/dual-battery-slides-2016.pdf
Some of us have been doing this for years and have cold beer and hot espresso every night. It is not hard to design a proper battery system for your camper, but you have to do it right. Worrying about flatting the camper battery or needing to self-jump indicate that you have a poorly designed system.
A Jeep Cherokee is a small vehicle for roof and weight, but as long as you pay attention to the numbers, you can make it work.
Partian Shot: 100w will only produce about 5A under perfect conditions, and, as conditions are rarely perfect, 200w of solar is a good minimum.
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luthj
Engineer In Residence
I am not familiar with your vehicle, but moving the evap canister should be pretty straight forward. A couple of extended hoses, and possible a extension to a wiring harness. It can go just about anywhere that isn't near the exhaust.
I would like to point out that a deep cycle bank in the 200AH range should have no problem starting an engine. In the 100AH range it depends on the batteries design. AGM deep cycle batteries generally have high cranking currents available. For example, the expensive lifeline true deep cycle batteries will easily start an engine, providing as much CCA as a similarly sized flooded starter battery.
With a well designed system, it is possible to use the deep cycle bank as the engine battery by flipping a switch. No other complex machinations, or battery matching/swapping are needed.
Redundancy and swapability of batteries looks good on paper, but in practice designing so you shouldn't need to do so, is more important in my opinion.
I understand the temptation of readily available starting/dual purpose batteries. But going with a true deep cycle from a brand with good history will provide much better results. Just make sure it gets charged right, even if that means a good shore power charger once a week for 12 hours.
I would like to point out that a deep cycle bank in the 200AH range should have no problem starting an engine. In the 100AH range it depends on the batteries design. AGM deep cycle batteries generally have high cranking currents available. For example, the expensive lifeline true deep cycle batteries will easily start an engine, providing as much CCA as a similarly sized flooded starter battery.
With a well designed system, it is possible to use the deep cycle bank as the engine battery by flipping a switch. No other complex machinations, or battery matching/swapping are needed.
Redundancy and swapability of batteries looks good on paper, but in practice designing so you shouldn't need to do so, is more important in my opinion.
I understand the temptation of readily available starting/dual purpose batteries. But going with a true deep cycle from a brand with good history will provide much better results. Just make sure it gets charged right, even if that means a good shore power charger once a week for 12 hours.
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Won't argue any points made. The research I've done supports that as well.
For me, my swapping 'want' has more to do with me having several vehicles that can already fit an H8 with no alterations. In reality the dual battery part of my solar setup is little more than a trickle charger to keep a starter battery handy whenever I want one. That's also a reason for mounting it inside, instead of burying it under the Heep somewhere.
Otherwise I'd go with a lithium house battery. But that's really only because I think the Grand Cherokee weighs too much already. (And yes i know how silly that sounds right after i say I'm going to put a giant H8 in there)
For me, my swapping 'want' has more to do with me having several vehicles that can already fit an H8 with no alterations. In reality the dual battery part of my solar setup is little more than a trickle charger to keep a starter battery handy whenever I want one. That's also a reason for mounting it inside, instead of burying it under the Heep somewhere.
Otherwise I'd go with a lithium house battery. But that's really only because I think the Grand Cherokee weighs too much already. (And yes i know how silly that sounds right after i say I'm going to put a giant H8 in there)
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Good advice! Nice quick and easy slides as well, I appreciate the input.
For the immediate future, I’ll set up the solar panel on the roof and charge the starter battery. I won’t run the fridge 24/7 but sometime this fall when I can swing it I’ll find a spot for a true deep cycle battery and use something like the blue sea acr to isolate it and still keep the solar. I guess I could use a deep cycle in the starter position but I think at that point I might as well buy the deep cycle for a dual battery setup.
Thanks so much!
DiploStrat
Expedition Leader
The combo of a LiFePO4 battery and a battery to battery charger may be an excellent option for a smaller vehicle like a Cherokee. The B2B makes for easy one stop shopping by providing isolation and voltage correction in one device. Sterling makes a range of products and REDARC makes one that includes a solar controller. (Maximum output 40A) Just be sure to keep the battery from freezing. There are several threads on this forum were people are doing this. Initial reports are encouraging.
devero4
Adventurer
I agree with which was stated above. Listen to luthj and run with it. This thread has A TON of good information. One thing I might add is that the MPPT controllers are worth the extra buck, especially in shaded conditions. You will also keep your AGM healthier with the featured 3 step charging. I recently purchased a Victron 75/10 with bluetooth for my DIY generator for around $110. I would purchase it again!
Chris
Chris
FlipperFla
Active member
If you use a start battery in a deep cycle application you are going to damage
the battery, Start batteries are not designed for deep cycle use. Look on the back of the solar panel it will tell you the Amp output it is probably around 7-8 Amps I would advise installing a deep cycle house battery and a ACR battery link. Also look on the fridge and see what the Amp rating is. Deep cycle batteries are rated in amp hours in minutes this is rated on a 25A load. for example if a battery rated at 100 minutes the means drawing 25amps the battery will run for 100 min. If you were drawing 1/2 of that at 121/2 amps the battery is going to run 200 minutes and so on. Look at as time. Your taking time out of the battery and putting time back in. I used to work at a west marine and had trouble with Bass boaters all the time bringing back batteries that they would say were defective. What they were doing was using the trolling motors all morning fishing for 4-5 hours, basically taking 4-5 hours of “time” out of the batteries then the 60mph run back to the ramp in 15 minutes. So the just put 15 minutes of time back in the batt. NOT 4-5 hours of time.
The difference between a deepcycle and a start battery is the thickness of the plates. In a start battery the plates are thin and designed for a high current shot sort of like a lighting bolt. Just like if you cant get your truck started after 4-5 long cranks the battery is shot. So basically Big draw short time. A deep cycle battery has thick plates and is designed for a low draw for a long period of time ..... small draw long time. Hope this helps any questions give me a shout, I will be glad to help.
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Just got back from a short 3 day trip in the sierras. I have my solar panel installed under the roof rack, and it’s able to slide out while still connected, or slid out entirely and connected with an extension cord I made with landscape wire.
With the fridge set at 36 degrees, ambient temps in the mid 80s/high 40s the, the solar kept everything running during the day and also recharged the battery from the night time. I set the cut off to “medium”. The fridge never turned off.
I also ran 10 awg wire to the back direct to the battery, and it has helped with the voltage drop a lot as well.
Sometime I’ll install a 2nd battery, as the sunlight hours are only getting shorter at this point. I also understand that it is harder on my starter battery.
Though in the winter I can probably just leave everything outside
Thanks for the tips everyone!
With the fridge set at 36 degrees, ambient temps in the mid 80s/high 40s the, the solar kept everything running during the day and also recharged the battery from the night time. I set the cut off to “medium”. The fridge never turned off.
I also ran 10 awg wire to the back direct to the battery, and it has helped with the voltage drop a lot as well.
Sometime I’ll install a 2nd battery, as the sunlight hours are only getting shorter at this point. I also understand that it is harder on my starter battery.
Though in the winter I can probably just leave everything outside
Thanks for the tips everyone!
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Guys, good thread but I got lost quickly and really don't understand it, so with this in mind, I do have question...
I have a 2014 Jeep GC with a ARB 37L fridge, I bought a Universal UB121000-45978 12v 100AH Deep Cycle AGM Battery 12V 24V 48V(Black) to run as a house battery and planned to have a gizmo (not sure real name) hooked up so starter battery will juice it while Jeep is running. I currently plug ARB into rear cigeratte lighter and it's worked flawlessly so far.
So my question...in light of this conversation, can I just replace my Jeep's battery with this one and not worry about having a second battery as it sounds like the AGM will give me much more and longer power.
I only go out for day or two but have ARB hooked up during week.
I have a 2014 Jeep GC with a ARB 37L fridge, I bought a Universal UB121000-45978 12v 100AH Deep Cycle AGM Battery 12V 24V 48V(Black) to run as a house battery and planned to have a gizmo (not sure real name) hooked up so starter battery will juice it while Jeep is running. I currently plug ARB into rear cigeratte lighter and it's worked flawlessly so far.
So my question...in light of this conversation, can I just replace my Jeep's battery with this one and not worry about having a second battery as it sounds like the AGM will give me much more and longer power.
I only go out for day or two but have ARB hooked up during week.
The bottom of the panel is 6 ft 5” from the ground so I’m not too worried about anyone hitting their head on it, though that would certainly hurt! Also, since I’m really only using the solar while I’m out in the country I don’t mind not charging while in town or in a parking lot. I’ll be driving often enough then to keep everything charged up and running. I don’t use the fridge while I’m around town every day anyway.
At full extension if I’m parked right I don’t really have much shading, but if I do or if it’s not really aimed at the sun I will just take it down and use the extension cable, it is pretty quick and much less of a hassle than I thought it would be. Extending the panel is more of a quick option that happens to work OK but in all reality I’ll probably end up removing it to I’ve a better aim anyway. It does lock in the open/closed position so it won’t slip out.
68 Camaro, sorry about the thread being confusing. Basically I wasn’t sure if 100 watts of solar would be enough for my uses and if I should run a 2nd battery. So far, it is enough but In the long run I should run a 2nd battery to keep my starter alive longer.
For your setup, I think a 100ah battery sounds like plenty. As long as you can recharge it properly it should work out for you.
However, I don’t think that battery looks like it would be a good starter battery. I’ve seen plenty of good sized deep cycle batteries that will work as a starter, but I would stick to a better brand in that application. Someone will chime in with a good recommendation for you.
I forgot to add about voltage drop:
The dometic app was reading the same voltage as the battery...until the compressor kicked on and provided a load. I was only looking at the voltage with no load so I didn’t see any voltage drop. Lesson learned!
Wiring direct with 10awg wires (with a 10amp fuse) there is only a very very small drop when the compressor cycles on, then quickly returns to the higher voltage. I think that is one reason why the fridge didn’t make it through the night!
On our last trip before the sun came up the battery voltage was 12.3 volts, as soon as the panel got full sun the voltage rose quickly. I definitely see a difference in solar output by aiming the panel directly at the sun as well.
The dometic app was reading the same voltage as the battery...until the compressor kicked on and provided a load. I was only looking at the voltage with no load so I didn’t see any voltage drop. Lesson learned!
Wiring direct with 10awg wires (with a 10amp fuse) there is only a very very small drop when the compressor cycles on, then quickly returns to the higher voltage. I think that is one reason why the fridge didn’t make it through the night!
On our last trip before the sun came up the battery voltage was 12.3 volts, as soon as the panel got full sun the voltage rose quickly. I definitely see a difference in solar output by aiming the panel directly at the sun as well.