3600mAh Extended Battery & Cover for Novatel MiFi 2200 - Lasts up to 3x Longer than Standard MiFi Battery!
[HLI-MIFI2200XL]

Well it works. I mean you get BIG battery, you get MORE time to use the device. And it is a chunky battery, but it still fits in my pocket. I haven't calculated exactly how much more I get out of it. But I know I can go 6-7 hours without charging again. Road warriors who need connectivity and don't have the luxury of being able to plug in often will appreciate this. 4 stars. The only thing they can improve on is the bulkiness of it. Nobody's perfect.