Help! Thinking of adding a second battery as backup

[superslidestyle]

I'm thinking of adding a second battery to my Xterra but not sure as to how it should be wired.  I'll probably use an Optima Group 31 size, but not sure if I should use a kit like this one:

http://www.dfna.info/html/dual_battery_kit.html?gclid=CKz_34bjwaQCFRL6iAodByzVEQ



Thought this article might help me also:  http://www.expeditionportal.com/equipment/vehicles/feature_vehicle/part3/

[Paul]

I have one.

I wanted one that I could take out of the vehicle so that I could:

1. Use to to provide power to a distant requirement - like a ham radio during RACES duty or to jump a stalled truck along a trail.
2. To lighten up the truck - batteries are pretty darn heavy already.

I ended up putting in a large solenoid isolation system, a switch to drive it, and a jolly big plug to pair with a jack on the battery.

Help! Thinking of adding a second battery as backup

Help! Thinking of adding a second battery as backup

Help! Thinking of adding a second battery as backup

Help! Thinking of adding a second battery as backup

Help! Thinking of adding a second battery as backup

Help! Thinking of adding a second battery as backup

[AV Xterra]

Ah, is there nothing PowerPoles won't do.

[superslidestyle]

 i bought a 160A battery isolator on ebay.  What I still don't know is whether I should mount it inside a battery box with the battery, or in the Trunk area somewhere?  Do I still need a selector switch to change with battery is in use?  what size cables shoud I be using?  

How do I wire in a 1000/2000W power inverter?  What size and type of protection do I need for the battery and the inverter?  I saw the inverters at Harbor Freight and the 1000W owners manual specified min. 4AWG wire with a 240A fuse with 4-40A automotive blade fuses inline inside.  I don't know how they got their math buth that would be literaly the biggest fuse in the whole vehicle.  I could always use stereo quality fuses and wires for a cleaner look.  Should I look into a Blue Sea fuse block also?

Hey Paul?  The pic of the wires coiled up and large alligator clips, that's the one inside the battery box right?  Are those big enough to carry the neede amps to restart the vehicle if the main one goes low?  How do you have the other wires going under the carpet wired up?  To the dash switch or straight to the main battery?  Where do you buy those types of connectors?

I know it's alot of questions so thank you for your patience and help.

[superslidestyle]

Ok, I got a 100A fuse assy. from Lightning Audio/Pep Boys and 4GA amp wire from the engine bay to the trunk area.  With the battery isolator, do I still need a lrg. battery selector switch?