The Anker Battery pack will out put 5, 12, 16, 19V DC and you can buy the adapter cable for the SP3 to charge with. You have to be very careful on your voltage and polarity of the cable. considering the one in the
amazon link is only 20,000 mah, I'm unsure of the mah rating of the sp3 battery, I doubt you're going to get more than a few charges from it. Be very careful of course, not to choose the wrong voltage, plug your cable into any other device, etc.
Correction. That anker battery supposedly will NOT work. Others have said it does NOT put out enough amperage. Seems the magic number is 2.15A at 12V.
Battery pack:
http://www.amazon.com/gp/product/B00B45EOYS/
Cable:
http://www.amazon.com/dp/B00PBGVQQU/
I don't personally use the above combo. I have a different "big battery" that does 5v and 12v and I made my OWN cable to I know it's wired right that I use on occasion. I could get 2 charges out of it but not while powered ON. I'd always do the recharge cycle with the devices OFF. I have a solar charger for the big battery, but that honestly takes forever to charge it with. LOL