If you want some real-world info on building a Li battery bank, check out my cousin's blog, where they've been gutting and rebuilding a '64 GM bus. Will be using an entire Nissan Leaf Lizard battery (plus 1 extra module) to power it, with 8 435w panels on the roof. URL is
http://www.beginningfromthismorning.com/. Fascinating stuff. Had I a spare grand to play with, I'd build a smallish battery, with only 8 modules, paired into 12v (actually 14.8v) batteries, then paralled. Gives almost 500 ah capacity with a total weight of the batteries right at 67 lbs, or about the same weight of a single T105 6v. :-)
Lyle