I'm going on a 5 day trip and I have no control over when and where I will have access to power outlets. I do not want to invest in an expensive mobile battery charger, as after this trip I'd probably never use it again. I've seen the Eneloop Stick Booster years ago, but today it seems like it disappeared or has been discontinued, and it only seems to exist in Japan and the US (I'm in Europe) for some reason, even though it sounds like the exact thing I'd need. I have tonnes of Eneloop AA batteries, is there a way to put them in some box that has a USB port, and voila? That sounds like it would be cheap as I wouldn't be paying for the batteries which I already own. In addition to my Eneloops, I could just buy AA batteries in any shop and use those as well. Does this method not work, or why am I not seeing anyone do this? It sounds like it would make a lot more sense than paying for an expensive battery pack just to charge your iPhone.