I have one of the LVMs from NRS and it's not nearly the battery hog some would lead you to believe. I carry a small SLA battery that is rated at only 7 ampere/hours. I can use it to inflate and deflate my 10 1/2 foot Scadden Outlaw Renegade (which has five air chambers including an inflatable floor) as well as inflating my Exped Downmat sleeping pad, and I can do it multiple times without recharging the little battery. The battery I use only cost $13.50 at Amazon too. I use a K-100 and K-Pump's Kwik Gauge to top the 'toon off to the recommended 3 PSI. It's a great combination.
I run mine off a lawnmower battery. Inflates my big boy cataraft easily. I get dozens of float tube fill ups on it before needing to recharge.
