Dual battery for under $400

Here’s the set up for a dual battery for just around $400 and that includes a $200 battery that I used

Parts:

$135 Cole hersee 48530 Smart Battery Isolator 200A

Cole hersee 48530 12v smart battery isolator solenoid 200 amp. You can find one on eBay for around 80-90 and it’s usually Pre-wired

About 50 feet of 2 gauge red wire

5 feet of black (this is all depending on where you ground your battery)

Terminals for the battery

2 gauge eye hole terminals for the wiring to the battery and fuses (15)

2x 200 amp fuses with housing

16 gauge red and black wire for the volt reader and to ground the solenoid

Volt meter

Then whatever battery you decide to go with. If you’re doing in cab find a sealed battery.



If you don’t have one a hydraulic crimper for the 2 gauge terminals


Photo of the set up:



Here is the wiring diagram that I used:

 

I was looking around for battery options and found this thread. Your workmanship is impeccable but you have an unprotected cable from the main battery all the way back to the fuse at the solenoid.

 

That's a true statement. That battery cable needs to be fused no more than a foot or two from the battery.