The battery only lasts 14 minutes. Then you have to charge it for a few hours. Hmm, you're better off really doing this by hand.
Considering this is a 10.8v system, and you've got a 14 minute runtime, you can calculate that using a 3 cell li-ion battery composed of the standard 18650 cells, or in this case a 6 cell 2s2p 16340 pack. You've got about 24 watt hours lasting about 14 minutes. And I'm pretty sure that's exaggerated a bit. The motor will put quite a strain on the li-ion batteries so you'll drop probably somewhere around 1/4 to 1/2 the power between the motor and batteries. And if you make a habit to use it completely, expect battery longevity to go down the toilet. You'll end up ruining the batteries long term.
So you've got maybe a 50 watt motor. About equivalent, to a little less than a 6" wax spreader polisher. But the downside is you've only a 3/16" orbit. Which is less than the orbit diameter of 5/16" on the wax spreader. The wax spreader in this case having similar power and a larger orbit diameter will be more effective.
So it'll be better to just get a 6" wax spreader, mod it like I have done for foam pads, put an extension cord, then for power buy a deep cycle battery and 120 volt inverter and an inexpensive charger or even a good one to charge it faster like this hobby one.
http://www.hobbyking.com/hobbyking/store...Warehouse_.html
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3359414/6"_wax_spreader_mod#Post3359414
A 115 Ah deep cycle battery will easily last 8 continuous hours of use with less than 50% depletion. With a wax spreader I can usually do a complete polish and wax with about 3 hours of continuous polisher use. So you can size your battery accordingly. This is actually the setup of last resort I used when detailing professionally and I had no access to power, it could last a whole day of detailing and then I would charge it up overnight and the battery would be no worse for wear and would easily last the full warranty period. I didn't want to run a noisy generator for hours on end annoying the neighbors of my clients.
Better than the 30 minutes of use you get with a $270 Griots polisher and I guarantee you'll have better results.
Or if you're not using this for a business and just need some power polishing, just get an inverter and connect it to your car's battery. As long as you don't use it for more than an hour or two, you won't be draining your battery enough to hurt things.
I'm guessing you're in an apartment and want to polish under your covered parking which has no power. I was often in a situation like this. Mobile detailing for apartment complexes can net you pretty good business as you have a whole lot of people in the same situation, the people want their cars cleaned but don't have space to wash and wax their cars like a driveway. Rinseless washing and a portable rig like I described was a real moneymaker for me back in the day. I even had a 12v "wet dry" vacuum that although I couldn't extract carpet with it I could vacuum and use a two bucket scrub/wash and rinse/blot to do interiors.