Dual Battery Setup Help Needed Gen 3

I am wanting to put a dual battery setup in my 2016 Gen 3 Taco. I am going to be doing lots of camping/hiking/off-roading in it and need some help on which battery to use how/where I should mount the battery.

I'm currently building out the bed of my truck (camper shell on the bed) to have a bed inside it so that I can sleep in the truck while I'm out on the road and not hiking. During those cold nights up north (CO,UT,AZ,MI,KS, etc.) during the winter, I was hoping to run, sparingly, a small space heater inside and the one I have picked out is 900W. I'm no electrical guy so this is why I'm asking...

If I wanted to run that for a few hours on the cold nights but most of the use would be for computer/cell phone/LED rope lights, what size battery, isolator and wire should I be using? Please help a new Taco owner out, can't wait to get this whole thing built out!

Thanks!

 

I installed a dual battery system in my truck for similar reasons. 110 amp hour AGM. I'm no expert, but from the research I've done I don't think you're going to be able to run any kind of electric space heater, or even an electric blanket, for any meaningful amount of time on a battery system you're going to want to have in your bed. They simply draw too much power. My understanding is that even full size RV's don't use electric heat. There are calculators online you can use to calculate power draw. Keep in mind that if you want to use laptops and other electronics, lights, maybe a fridge, that's all going to draw power too. You also don't want to run your battery too low, so my 110 amp hour battery realistically will only have ~55 amp hours to give before I should charge it.

I'm planning to use a Mr Buddy style heater, and install a LP/CO detector that runs off my battery. Run it for a short time just before going to bed to warm things up, and just after waking up to change etc. I'll rely on a warm sleeping bag while actually sleeping.

I mounted my battery just behind the cab on the passenger side. I figured that was the most balanced place to put it, considering the gas tank and driver will be on the driver side.

I ran 4 gauge wire from the starter battery to my charge controller, as recommended by the documentation in the charge controller for my length of run. Then of course much smaller wire for all my peripherals. You can use the online wire gauge calculators again to figure out what size those need to be.

 

900W at 12v = 75 amps. Meaning a 75 amp hour batt will run for 1 hour at most. Then to recharge that batt will take many hours.

But that also answers your wire gauge question. Wire needs to handle more than 75 amps.

 

Check out this thread:
https://www.tacomaworld.com/threads...ts-see-them-multiple-batteries-thread.295653/

Lots of info if you have the time to read through. Can also search for different terms

I doubt you will be able to run a heater off of battery alone for any length of time though

 

Yeah, I'm seeing that a space heater is not a viable option now... I'm reading in other places that folks have had success with 12V electric blankets. Does anyone have any advice on that?

I'm looking at adding a Flat Plate AGM Exide Battery. I am also wondering where the best place to mount it is... I currently was going to put it in the bed of the truck under the bed frame that I am building. I will have an inverter and fuse panel with it.

 

Thanks for this!

 

Yeah he can

 

You're going to have to find the blanket you are thinking about getting, and then do the math to find out how much power it will draw, and then decide for yourself if you think it's practical for your needs. When I did the math, I found it was impractical even for an electric blanket.

You may also want to consider avoiding using an inverter if at all possible. There is a relatively high percentage of power loss/waste when you use one, and most of the time the devices you'd be using are going to be DC anyway, so you'd be converting from DC to AC back to DC for no reason. For laptops etc you'd be better of just buying a new 12v power cable in my opinion.

 

Buy a good quality down sleeping bag and a sleeping pad. This will work out to be less than the battery, bracket, isolator switch, wiring etc. in the long run. Use a buddy heater or a small stove in the morning to warm up, have coffee, and get dressed. I had used this setup for many years.