2006 Chevy Express here,...and in wanting to add a battery bank that will PRIMARILY POWER THE 2 Cig Lighters (i.e., Aux Outlets) in the van for trickle charge while the van is not on,....I have been following the article below as a reference and have a very basic question about the installation of the battery with a continuous duty solenoid...


Van Dwellers: Adding Extra Batteries to Your Van Dwelling - Yahoo Voices - voices.yahoo.com




perhaps he is leaving a step out, or I am not grasping the concept....


but I am at a loss as to how the Aux battery will be separate from the main battery while powering the Auxiliary Outlets through the Solenoid. The Aux outlets are always hot as we know... but.... I'm wondering how they will be powered from the Aux and leave the Main alone unless I do some rewiring I have not seen mentioned.


Should I assume that this continuous duty solenoid will simply do it for me? Will I need to add something to the fusebox (slot 29) that goes directly to the Aux Batteries? And if I do so,....would that not open up flow back to the main battery (which is what I wanted to separate while the car is off to begin with)?


Would I have to install a diode somewhere to cut off the flow back to the main while the car is off? All replies are appreciated!

 

The way I read it, the solenoid would connect both batteries when the van is on and running (or at least in the "run" key position)

But the Aux battery is separate when the solenoid is powered on (no key in "Run")

What he does not explain is how the house 12v plugs are powered via the aux battery.

I would think that you would just connect (and fuse) a separate 12v plug directly to the aux battery so when the van not in run position the "aux" 12v plug is powered from the "aux" battery, then when the van in run position both batteries are charged.

The expensive battery isolators are usually High Power Diodes, but can be expensive, the solenoid of course can be quite affordable but will be two way when the solenoid is powered up.

Not a bad way to do things...

Hope that makes sense...

 

Why not just pickup a cheap battery maintainer?

 

Use the original power source for the 12v outlets to charge the battery. Just route it through a 30 amp Bosch relay. Use a switched power source to activate the relay. (I just run from the plug to my auxiliary battery to my 12v fridge and unplug for overnight).

 

This is the "classic" dual battery setup. Basically when the key is ON the solenoid links the batteries so that the alternator charges both of them. When the key is OFF or out the batteries are separated so that you can drain your auxiliary battery without fear of draining the starting battery.

I prefer Cole Hersee's smart battery isolator (about $80-100) which is like the other solenoid BUT monitors the starting battery and charges it before charging the auxiliary battery. It also has a "jump start" feature so that if your starting battery is low, you can link the batteries for added cranking power.

Attach your 12v plugs to the + terminal of the aux battery with a 15 amp fuse and you'll be good to go.