Second battery and solar advice needed

[pkelly72]

I’ve got a 2015 ram 2500 with the 6.4L. Currently running a group 31 agm battery in the vehicle. I’ve got an Atlas camper scheduled to be finished in June and looking for some advice on power.

I’ve got 2 renogy flexible solar panels 100&50. A victron 100/20 smart controller. I plan on running a fridge, lights, charging, maybe coffee maker, possibly heater and or a fan.

looking at getting a National Luna power pack and hooking up to main vehicle battery and solar.

Does this seem like a good solution? Is there a better solution for my needs. Any advice would be appreciated before I spend the money.

*I looked but couldn’t find a way to mount a second battery under the hood but if there’s another solution out there please let me know.

 

[hour]

Dunno what type of heater you're talking about, but you'd want to avoid it if it's electric-only. Aka propane camper heater, diesel air heater good. Electric heater bad. It'd be an enormous draw on the system and while you're already going to have to plan for that with the coffee maker, a coffee maker does its job in a few minutes.

If you ditch the idea of electric heat or were never considering it in the first place - good. An electric blanket is a better choice. That leaves the dreaded coffee maker which could use 1500 watts and necessitate a rather large inverter. I'd look in to aeropress, presto k-cup maker, french press, or anything else. That way you don't need an inverter at all. Fridge, lights, charging, fan, (a 12v heated blanket, or diesel air heater, or camper furnace) all straight off the battery. You could still carry a small inverter capable of blowing up an air mattress or charging laptops that don't have 12v adapters.

You have a lot of room to grow with that 100|20 charge controller. I'd use the 50w for something else and add more 100w panels. You could run 4 in series and be under the 100 volt limit of the charge controller, while over-paneling the system and ensuring you're maxing out the charger even in less than ideal conditions.

Unless i'm missing something, the power pack is like $500 and you still need to supply your own battery. If it were me i'd spend that money on a toolbox or ammo can, some panel mount anderson powerpole connectors, a hole saw, a renogy or victron DC-DC charger, and a lifepo4 battery with protection (BMS). I just received 4x100ah cells from Aliexpress for ~$170 to my door that are testing at 98 amp hours. You won't get that kind of usable capacity from a single 12v lead acid battery. Pretty easy to assemble and many DIY videos on youtube. All in, it'd be about the same as you'd pay for a national luna box alone.

Even if I were using a normal deep cycle lead acid battery, I'd likely still skip the power pack. Guess I don't see the value when I can build something adequate for so much less.

 

[pkelly72]

Dunno what type of heater you're talking about, but you'd want to avoid it if it's electric-only. Aka propane camper heater, diesel air heater good. Electric heater bad. It'd be an enormous draw on the system and while you're already going to have to plan for that with the coffee maker, a coffee maker does its job in a few minutes.

If you ditch the idea of electric heat or were never considering it in the first place - good. An electric blanket is a better choice. That leaves the dreaded coffee maker which could use 1500 watts and necessitate a rather large inverter. I'd look in to aeropress, presto k-cup maker, french press, or anything else. That way you don't need an inverter at all. Fridge, lights, charging, fan, (a 12v heated blanket, or diesel air heater, or camper furnace) all straight off the battery. You could still carry a small inverter capable of blowing up an air mattress or charging laptops that don't have 12v adapters.

You have a lot of room to grow with that 100|20 charge controller. I'd use the 50w for something else and add more 100w panels. You could run 4 in series and be under the 100 volt limit of the charge controller, while over-paneling the system and ensuring you're maxing out the charger even in less than ideal conditions.

Unless i'm missing something, the power pack is like $500 and you still need to supply your own battery. If it were me i'd spend that money on a toolbox or ammo can, some panel mount anderson powerpole connectors, a hole saw, a renogy or victron DC-DC charger, and a lifepo4 battery with protection (BMS). I just received 4x100ah cells from Aliexpress for ~$170 to my door that are testing at 98 amp hours. You won't get that kind of usable capacity from a single 12v lead acid battery. Pretty easy to assemble and many DIY videos on youtube. All in, it'd be about the same as you'd pay for a national luna box alone.

Even if I were using a normal deep cycle lead acid battery, I'd likely still skip the power pack. Guess I don't see the value when I can build something adequate for so much less.

Thanks, got a link for the batteries?

 

[pkelly72]

If using mismatched solar modules, its better off if each module has its own controller.
Its not tragic.
Mis-matched modules will work if combined either series or parallel to a single controller but total array wattage is reduced. You wont get 150W out of the system.

I didn’t know that. So I’d need to run 2x100’s? Or the like?

 

[john61ct]

Victron 75/15 can handle 230+W

I think 75/10 is the smallest but not much cheaper.

I bet the 100/20 will get most of its value back secondhand.

Or use the 50W panel for keeping starter batt topped up with a $20 PWM SC, and get another 100W to match.

 

[hour]

Thanks, got a link for the batteries?

Yes, these. There are others to be had too if you want larger or smaller. The big 272ah/280ah lifepo4 cells will be the best bargain but I'm not complaining at 98ah for $170. If money were no object and I weren't interested in building batteries - I'd just get a 100ah Battleborn off the shelf for a bit under $1,000. The battery monitoring system (BMS) is a 120 amp Smart BMS (bluetooth state of charge, net current, individual cell voltages, temperature, some other stuff) and was $70. Diysolarforum dot com if you want to learn more, find suppliers, yadaya.

 

[XPLRMOR]

Thanks, got a link for the batteries?

I just ordered on of these, seems like the best price. 12 Volts 100Ah Lithium Iron Phosphate Battery | HQST Solar (hqsolarpower.com)