Single battery setup vs Dual battery setup
- Thread starter Mr_Miyagisan
- Start date
Scoutn79
Adventurer
The idea of a solar panel is to charge a battery(s) when there is no other charging method being used (no generator or alternator being used). So to answer your question yes.
Darrell
Thanks for responding. My concern is that I've read it might not be safe for other components of the car when the battery is being charged by an external source (other than by the alternator). My goal was to find out if there is a safe way to to charge a single battery system while it's still connected to the car. I wanted to avoid having to disconnect the battery from the car every time I need to recharge it via solar or AC at home. With a dual battery setup, it seems that a battery isolator does that job and charges the aux battery.
Scoutn79
Adventurer
I'd like to know where you heard that I never have. You can either wire the controller (depending on the power of your panel you may or may not need a controller) directly to the battery or just use a 12v cigarette plug and plug it into an always hot outlet.
Some very low watt panels are just for maintaing batteries in an RV or boat or ATV since they can sit for months between usage and these don't need a controller but anything over say 10 watts would need a controller. If you are planning on using the solar panel to keep your battery charged whne using a fridge any panel you get will need a controller.
You will want to start a new thread for this instead of hijacking the OP post.
Darrell
Thanks. Just bunch of random forums I read while trying to do research on the issue. I figured folks here would know more, I'll start a new thread.
dwh
Tail-End Charlie
Dunno where you read that, but it's a load of BS.
To fully charge a lead-acid battery, you have to get it up above 14 volts and hold it there for as long as it takes it to absorb all it can.
Since every car builder knows that, every component of every car is designed to handle it.
You can do the job with an alternator, a shore powered charger, a solar system - doesn't matter, they all do the same thing; raise the voltage and hold it there.
Depends on the isolator.
If it's a smart isolator, a.k.a. automatic connection relay (ACR) such as sold by Bluesea, Samlex, National Luna and others, then it detects elevated voltage on either side and automatically connects the batteries together so they both charge - together - from a single source, whether that source be an alternator feeding to the engine battery or a solar system feeding to the aux battery.
I have a single battery setup in my van with a 100w renogy solar panel and charge controller. Pretty much the only thing I power is an indel b fridge. I have a national luna single battery monitor that I stare at way too much. The setup has worked great and I have only had trouble with it on one trip. We were camped in tree cover in 100 degree weather, the sun only hit the solar panel for about an hour each day. I didn't really want to move the van into sun because I had an awning setup etc. That being said I set the fridge on a lower setting but never turned it off and the van fired up fine after a couple days of sitting. We do a couple 1-2 week long trips a year and a lot of weekends.
I keep going back and forth about adding a second battery. The setup has worked great as is, other than like I said earlier I can't seem to not be checking the battery monitor all the time. One thought I had was adding another 100w panel just to keep up with the fridge even easier in hot weather. The controller and roof racks are already setup for it. Any thoughts? Also was wondering about any experience with the jump packs on an older v8? I've also thought about getting a solar suitcase type panel for the shade times. I do really like having the panel mounted and just always setup though. We have kids and anything that take one step less of setting up is kinda the goal. My thinking that maybe the two mounted panels might help makeup for when the exposure is not optimal?
I keep going back and forth about adding a second battery. The setup has worked great as is, other than like I said earlier I can't seem to not be checking the battery monitor all the time. One thought I had was adding another 100w panel just to keep up with the fridge even easier in hot weather. The controller and roof racks are already setup for it. Any thoughts? Also was wondering about any experience with the jump packs on an older v8? I've also thought about getting a solar suitcase type panel for the shade times. I do really like having the panel mounted and just always setup though. We have kids and anything that take one step less of setting up is kinda the goal. My thinking that maybe the two mounted panels might help makeup for when the exposure is not optimal?
Bear in NM
Adventurer
Bsk,
I built a couple of "choices" last year for solar. I first started with a second battery in my truck. While I find it fun to piddle with the solar when camping, having a single battery and a fridge would tend to stress me out, as well. The second battery in my truck and the batteries in my homemade solar generator mean that I can camp stress free, even in non-perfect sun.
It seems to me that based on your single experience of camping in a shady spot gave you some good perspective. If adding a second fixed panel to the same location as your first, that configuration will not beat shade. A second panel that can be run into better sun would make more sense. But then you do have kids and maybe dogs and wires on the ground to contend with. My single 135 panel is moveable, and I like it that way, as I too am likely to not want to park in direct sun. I am going to add a second 135 panel this summer, but it will also be portable.
For me, I like to look at options. The second battery gives me the ability to jump start myself. The other options there would be the jump pack, or relying on other rigs to help with a jump. I decided the second battery was a better investment, as now I can help myself when remote, even if I do not pack my solar/fridge for the trip. I guess more bang for my buck and less stress. And if you can add a second battery that gives you 30 or 40 amp hours of usable juice (above the 50% discharge), you could almost go an entire 2 day weekend on the fridge with no solar.
My thoughts on the second panel would be to have it not fixed, especially with just one battery. It would leave you more flexible.
Craig
BagiMT
Naturalist
I have been trying to find a marine/deep cycle battery at Costco. The only one I saw was a 27DC but that does not seem to be a AGM and only has 12 months of warranty. Price is $80 for that one. Not a bad deal but I would ratter get an AGM for a bit more. What model did you get? What Costco?
High Country
Member
This thread has some good info, debating this myself.. thank you
rickc
Adventurer
My approach is a little different; I have only one vehicle and I don't want to leave all my expensive goodies inside when it's at an airport parking lot for a week or more or when I'm not camping. Also, my 2016 Colorado 3.6, despite having a standard sized battery tray, has the tiniest stock truck battery I have ever seen; as commented on earlier in this thread, modern electronics have changed; batteries are smaller and even alternators have lower outputs than were typical in the past. I'm gone with a modular approach:
Up front in the engine bay, a Wirthco 150A Battery Doctor will be connected to the main battery live and a big (expensive) 2 gauge live will run down, along and up to the front left of my truck bed. Inside it will connect to a 150A circuit breaker and on to connect to the live big connection of my ArkPak 730, loaded with a Group 31, AGM, 105Ah, 1000 MCA battery. The negative from the ArkPak will go down to a chassis ground, yet to be located.
This setup will allow me to run my fridge and anything else I want from the back, give me an emergency start back up and charge the ArkPak when I'm driving. I'm also planning to make a secondary power connection for my ARB Twin Compressor in-a-box so that I can connect it directly to the Arkpak Anderson outlet and leave the thing in the truck bed when using it. I'll post pictures when I get it all set up.
Up front in the engine bay, a Wirthco 150A Battery Doctor will be connected to the main battery live and a big (expensive) 2 gauge live will run down, along and up to the front left of my truck bed. Inside it will connect to a 150A circuit breaker and on to connect to the live big connection of my ArkPak 730, loaded with a Group 31, AGM, 105Ah, 1000 MCA battery. The negative from the ArkPak will go down to a chassis ground, yet to be located.
This setup will allow me to run my fridge and anything else I want from the back, give me an emergency start back up and charge the ArkPak when I'm driving. I'm also planning to make a secondary power connection for my ARB Twin Compressor in-a-box so that I can connect it directly to the Arkpak Anderson outlet and leave the thing in the truck bed when using it. I'll post pictures when I get it all set up.
ArkansasDon
Observer
I made the choice to go a single battery. I run a VMax Tank 125ah AGM. The solar system I have gives more than enough power to charge & keep a reserve. I wanted to design a simple basic electrical system in my tongue box. I looked at many & talked with a guy who wires RV's. As you see you can not get much simpler than what I have. It's reliable, & safe.
My solar set up is Renogy, 2 100 watt portable suit case panels were I can connect both with a branch connector & pigtail cable parallel or just one 100 watt, 30 amp Renogy Wanderer Charge Controller w\ Battery Temperature Sensor, 20 ft 10 AWG cable.
My solar set up is Renogy, 2 100 watt portable suit case panels were I can connect both with a branch connector & pigtail cable parallel or just one 100 watt, 30 amp Renogy Wanderer Charge Controller w\ Battery Temperature Sensor, 20 ft 10 AWG cable.
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