Dual battery setup. What auxiliary battery are you running?

[Buckaroo]

it's difficult to imagine the perfect dual battery setup.
Technologies and personal budgets change just as you think you have tweaked yours to perfection :-(

 

[Bingham]

I had a lithium battery in my landrover, can't remember the specs but it would run everything for a few days without charging it. It cost a lot but IMHO it was worth it. I will be doing it again as some little asshole stone my disco and set fire to it

 

[Yroundrdn]

I went with 2 $78 costco deep cycle batteries. I have 100 wt solar but run a compressor style fridge and a few other things. One battery seemed to get lower than I wanted in the winter so I went with the two batteries and have never dropped below 12 V on them with the 100 amp solar. Obviously if I'm driving the alt charges them both up instantly but when parked or at home, the panel keeps them both charged and I have had not issues with the batteries.