Your Kindle is a pretty decent e-reader. It has everything you would need to get reading done at home and on the go. The battery life of these E-ink e-readers is pretty decent. You could always get a battery extender to get even more out of your e-reader. There are plenty of them around. These 3 stand out for the fact that they let you use AA batteries to charge your Kindle and other handheld devices:
System-S Backup Battery Charger Extender: we were able to use this to charge the Nexus 7 and Kindle. It works for other gadgets too. Just bring 4 AA batteries, and you are set.
Verbatim AA Power Pack: lets you charge a variety of devices such as iPhones, iPods, and e-readers. It even works for wireless Bluetooth headsets. A full charge can add up to 75% iPhone charge. Requires 4 x AA batteries.
MintyBoost Kit: want to make your own battery extender for your phone or tablet? This kit is for you. It is compatible with Kindle, Kindle DX, NOOK, and many other devices.
These battery chargers let you use regular AA batteries to recharge your Kindle and other e-readers. They are great to have in emergencies.