Car Camping / Trip Reports / Photos / Buildouts / “Overland” / Expedition Rigs Area (homeless?)

This relay plus cables is all you HAVE to have to make a dual battery. You lose some functions such as easy jump starting but you should have cables with you regardless.

https://theinverterstore.com/produc...vBs-oA-MF7oLPwLeWjPL0TMC76ZVecYRoCgPIQAvD_BwE

For just a little more money you can improve upon it.

https://www.wmjmarine.com/c29766.ht...bMgrYPNh9yNzz6o906JA6B8akeZywt-RoCc8IQAvD_BwE

 

some of that "automation" can be added with just a toggle switch for under 10 bucks. or for about 30 bucks more from just the basic isolator will give an automated setup

 

I am quite aware that you CAN do it on the relative cheap...but that's not really how I tend to do things.

 

Trust me, I spent a very long time researching what was needed to make a dual battery system for my needs. My setup is simple but robust and won't leave me stranded. And it has proven itself to be reliable without issue.

 

Not doubting you at all, and that's how I SHOULD do it, but...I'm a mallcrawling dork with #EAF ambitions

 

I plan to go dual battery down the road but for now, I started by upgrading to a northstar 31m + pelfrey battery cage in the stock location. I generally have my fridge plugged in full time and at camp, i usually have a ham radio turned on most of the time and occasionally some lights. the 31m handles all these loads without issues. I just carry one of those jumper packs just in case I need a jump.

Personally, I'd say do the group 31 option and if you think down the road you need a 2nd battery, you can add one then. But from what you're describing, a dual battery setup is overkill.

 

How many days you think you could leave your fridge on continuously? What's your solar set up, if any?

 

The best I've had it run was 13 days with the truck untouched and fridge never opened (left it at my buddy's shop on the lift and was surprised it was still on when I picked it up).

Typically, I've seen it run anywhere from 2-5 days with occasional opening of the fridge and it set at the low cutoff setting. Depends on the weather but its been around 80-100deg outside when I would get closer to the 2-3 days without starting the engine.

No solar yet, thats something on my to do list but so far, i just start the engine for 30 min or so twice a day if its really hot out just as a preventative measure to charge up the battery during the day.

 

Haven't gotten my CTEK d250s dual charger yet to charge my portable solar power pack. If I happen to flatten my starter, I just run jumpers from my aux to my starter to jump. It's real crude but works in a pinch, but like @dtaco06 said keeps you aware and vigilant. I'm personally not running lights bars and headlights while the truck is off for long periods of time. I'll be running a switch pro that has a voltage cut off for all my accessories that run off my main power.

https://www.tacomaworld.com/threads...-with-bs-thread.220278/page-664#post-17472946

 

I have a Columbia Overland dual battery tray for the stock location. Honestly, wish I had moved the batteries elsewhere as I’m starting to see a little bit of sag on the sheet metal.

Your mileage may vary.

 

If I ever go dual battery -OR- stop being lazy, I'd plan to relocate my battery(ies) to a tool box I'll hard mount in the bed. I don't want that much weight on the wheel well knowing its pretty thin sheet metal. I've seen other guys' trucks with the ripped sheetmetal.

 

This is the main reason why I ditched the 31m battery. I have several large cracks and sheet metal separation with in the inner fender core area.

 

Nevermind, continuing with second battery under the tray....I don't really slow down for bumps.

 

It wasn't necessarily the cracks, it was the noise that was associated with the cracks and seperation. All the squeeks, pops, rattles and moaning drove me freaken nuts.

 

What size positive wire from battery to battery ? I am just going to ground battery to frame with big grounding strap. Have some 0/2 copper welding leads laying around just looking for a reason to have some lugs crimped on

 

Why 1/0? I’m assuming both batteries are under the hood?
When I built my dual setup I used all 2 gauge. FYI there is a bolt hole on the top front of both sides of the frame. Easy to ground both batteries together.

 

Im using 2gauge cable. No measured voltage drop with the amount I used. Longer runs between batteries will require larger gauge obviously. 200amp circuit breaker from the starting battery to a 200amp isolator. And a 150amp ANL fuse to the house battery from the isolator. The house battery is grounded to the starting battery and not to chassis.

 

To each there own. I did not put any fuse between the batteries so I can self jump. The aux battery is grounded to the motor and the frame. Then I beefed up the grounds from the frame to main batt as well as the body ground.

I left the main batt out and started soul off the aux and it was just like the main so I knew it would be good in case of a self jump

 

Hmmm, I better get the big stuff then......I gotta run all the way to the bed

 

That might explain the slow but steady increase of noises coming from my front end.....