MacBooks are known for their great battery life, the new Macbook Air models can last up to 12 hours on a single charge. However if that still isn't enough, it may be a good idea to invest in a BatteryBox.
BatteryBox is a powerful 50Whr cell hidden inside a minimal casing styled on the lines of a MacBook power adaptor. It has enough capacity to power a MacBook Air for 12 hours or a MacBook Pro for 6 hours as well as fully charge eight iPhones. Surprisingly, the rechargeable Lithium-ion battery pack within it doesn't make the BatteryBox heavy at all. The accessory weighs just 255 grams and features cutting-edge battery technology that allows it to charge up to 80% in under four-and-a-half hours. There's also a MagSafe2 cord and an universal port for charging other USB devices.
You can pre-order the BatteryBox now for $139 and have it delivered to your door by the end of the year.