Solar/Dual Battery Options

[kithound]

Hey guys, recently decided I want to run house power and solar in the Monty. That said, I'm wondering what my options are – a buddy suggested a Goal Zero Yeti 400 and a 50w or 100w solar panel. It looks awesome, but it's a little spendier than I'd like and I already have a second car battery for the truck. Wondering if there's a way for me to use that existing/already-owned extra battery with the same or similar functionality. Items I'd be running/charging would be phones, laptop via USB-C, camera batteries, and ideally a small cheapo Amazon fridge. No clue if the car battery can support loads like that or be readily converted to accept solar inputs. Thanks in advance, all!

 

[KonzaLander]

How do you currently charge the extra battery?

I would take the simple approach and install a 100w panel on the vehicle and wire it through a solar charge controller hooked to the second battery. The charge controller will continuously charge the second battery and will stop charging if another charge source is on the battery. A 100w panel maintains my battery's voltage with a cheap Costway fridge running in the back for days while the vehicle sits.

Other popular options include a DC-DC charger with solar input, other all-in-one charge controllers with solar inputs or a separate dedicated power system for the house battery.

You might be able to get a few ideas from my dual battery log here:

Basic Dual Battery Install in a '99 Land Cruiser

With the addition of a fridge to my Land Cruiser, I really wanted to isolate the power used by accessories when parked to a dedicated house battery. There are many possible routes to achieve a functional dual battery setup; this is how I did it. Objective: Install a simple and cost effective...

www.overlandbound.com

 

[kithound]

How do you currently charge the extra battery?

Haha, I don't – I somehow wound up with two batteries and now it's just a spare. That setup sounds perfect though; what do you use to enable the battery to interface with your electronics? Is there a nice all-in-one housing that'll turn my Interstate battery into a Yeti (optimistic, I know). Thanks!

 

[KonzaLander]

Haha, I don't – I somehow wound up with two batteries and now it's just a spare. That setup sounds perfect though; what do you use to enable the battery to interface with your electronics? Is there a nice all-in-one housing that'll turn my Interstate battery into a Yeti (optimistic, I know). Thanks!

I know next to nothing about the Yeti, but my electronics are wired to my battery through a Blue Sea fuse panel.

 

[IAm_Not_Lost]

Hey guys, recently decided I want to run house power and solar in the Monty. That said, I'm wondering what my options are – a buddy suggested a Goal Zero Yeti 400 and a 50w or 100w solar panel. It looks awesome, but it's a little spendier than I'd like and I already have a second car battery for the truck. Wondering if there's a way for me to use that existing/already-owned extra battery with the same or similar functionality. Items I'd be running/charging would be phones, laptop via USB-C, camera batteries, and ideally a small cheapo Amazon fridge. No clue if the car battery can support loads like that or be readily converted to accept solar inputs. Thanks in advance, all!

Easiest way would be just to run wire from your starting battery to the auxiliary battery with a Voltage Sensing Relay in between so that you never accidentally drain your starting battery. This setup works well for charging an auxiliary starter type battery or a marine starter/deep cycle. Does not work well for effectively charging a dedicated deep cycle battery.

Then build a little battery box for your battery (or you could buy something like a Minnkota battery box that has cigarette plugs already wired and a breaker) and you could install the necessary 12v accessory outlets as well as installing a cheap solar charge controller if you wanted to solar input. You could build the box, get your accessory outlets, and buy a 100 watt solar panel and charge controller combo for very cheap (under $250 bucks) and have 90% of the functionality of a Yeti type product for 20% of the cost. It would just be a little bulkier and heavy.

Mind you, your car starter battery is going to be limited in it’s output. In your case I wouldn’t worry too much about discharge depth and would just use and abuse the battery since it’s a free spare battery and then when it dies upgrade to a marine deep cycle flooded that you can get for about $90 bucks that will have about a 90-100 amp hour rating (hard to calculate sometimes as most of the box store marine deep cycles don’t have standardized amp hour ratings).

Edit: not sure what your vehicle is but a flooded battery should be reasonably ventilated. You won’t want it in the same compartment you and your passengers are in, unless you can seal it off fairly well and ventilate it to the outside.

 

[kithound]

Easiest way would be just to run wire from your starting battery to the auxiliary battery with a Voltage Sensing Relay in between so that you never accidentally drain your starting battery. This setup works well for charging an auxiliary starter type battery or a marine starter/deep cycle. Does not work well for effectively charging a dedicated deep cycle battery.

Then build a little battery box for your battery (or you could buy something like a Minnkota battery box that has cigarette plugs already wired and a breaker) and you could install the necessary 12v accessory outlets as well as installing a cheap solar charge controller if you wanted to solar input. You could build the box, get your accessory outlets, and buy a 100 watt solar panel and charge controller combo for very cheap (under $250 bucks) and have 90% of the functionality of a Yeti type product for 20% of the cost. It would just be a little bulkier and heavy.

Mind you, your car starter battery is going to be limited in it’s output. In your case I wouldn’t worry too much about discharge depth and would just use and abuse the battery since it’s a free spare battery and then when it dies upgrade to a marine deep cycle flooded that you can get for about $90 bucks that will have about a 90-100 amp hour rating (hard to calculate sometimes as most of the box store marine deep cycles don’t have standardized amp hour ratings).

Edit: not sure what your vehicle is but a flooded battery should be reasonably ventilated. You won’t want it in the same compartment you and your passengers are in, unless you can seal it off fairly well and ventilate it to the outside.

Thanks for the reply! I decided to hold off and buy a drone for this trip instead of a battery – I don't have a fridge yet so I think I can probably get away with an inverter for the electronics I want to run right now. When I'm ready for house power I'll probably grab the Yeti 400 cause they're reasonably discounted, and that way I can bring it inside my house if there's a power outage, or put it on the patio with solar panels (which I already bought, d'oh!). Would be inside the truck, where I have a sleeper platform built, so I don't know if I could get away with a poorly-sealed battery. Any brand recommendations?

 

[IAm_Not_Lost]

Thanks for the reply! I decided to hold off and buy a drone for this trip instead of a battery – I don't have a fridge yet so I think I can probably get away with an inverter for the electronics I want to run right now. When I'm ready for house power I'll probably grab the Yeti 400 cause they're reasonably discounted, and that way I can bring it inside my house if there's a power outage, or put it on the patio with solar panels (which I already bought, d'oh!). Would be inside the truck, where I have a sleeper platform built, so I don't know if I could get away with a poorly-sealed battery. Any brand recommendations?

Battery brand? If you’re on a budget a cheap agm can be found online for around $100-150 dollars. That would be sealed. Otherwise I don’t have any strong recommendations.