Switching to Lithium Ion Battery Bank?

That's a pretty good read though I think his pockets are a bit deeper than most thus giving him some additional options.

In his blog he linked to this company for his battery source:

http://lithionicsbattery.com/product-category/12-16-volt/

They don't have any pricing that I can see so difficult to tell if they are an affordable option or not at this time.