There is a cheaper option that may interest you that is convenience personified.

For $100 you can buy a battery "brick" from Officeworks etc.

They'd give you around five full charges (or three quarters the butane charger) on a heavy-use phone like an S6 from flat and it can be plugged into a flat phone for immediate use or just top up the phone any time you want to. It, in turn, can be recharged without fuss from mains or from the car cigarette lighter. And in this age of tech you don't even need to read the manual.

I've been carrying an older lesser rated one in my backpack for phone and cycle lights etc for a couple of years and it is effortless. Indeed, now I see the greater capacity and falling prices I reckon I'll step out and buy another myself.

Example only, they come in all capacities.

http://www.officeworks.com.au/shop/officeworks/p/comsol-dual-port-power-bank-15000mah-cosp150dp

-- Edited by colinoldncranky on Thursday 11th of February 2016 11:58:28 AM