Had you thought about how to change the batteries in a battery pack? Apparently it’s impossible for many portable chargers, but Griffin TuneJuice battery pack can do it easily.
Unlike other some extended battery packs that integrate rechargeable lithium battery, Griffin TuneJuice battery pack uses three available-everywhere AA batteries to feed your device. Of course, the most advantage is that you can change the batteries at any time for your next device without waiting the charger fully charged. In addition to all models of iPhone and iPod, TuneJuice allows you to charge your other USB devices through built-in standard Type A USB port.
Griffin TuneJuice battery pack is priced at $39.99 USD. If you’re interested, jump to Griffin official site for more details.
Additionally, if you need more options, you might like to check Primo Power Core and the smaller USB emergency charger.