Just last week we featured the battery-cover-busting ZeroLemon 7000mAh extended battery for the Galaxy S III. If that's not enough for you and your globe trotting, electricity eschewing lifestyle, the company also offers an even more expansive 9300mAh battery for the Samsung Galaxy Note II. In case you're wondering, yes, it's perfectly normal to imagine Also Sprach Zarathustra playing in the background right now. Amazon's got the battery for a mere $39.99 (US price) at the moment.
At 9300 milliamp hours, the extended battery is exactly three times as capacious as the standard battery. Naturally this requires an extended housing, provided by ZeroLemon in the form of a TPU plastic battery back (it's the slightly grippy, rubbery material that a lot of cases are made from).