The ENERGI 10K is the perfect solution for someone looking for days of power. The huge 10,400mAh internal battery will fully charge your smart phone four times.buy here
Rechargeable 10,400mAh internal battery
Universal USB ports for charging most devices, including iPod®, iPhone®, and iPad®.
4.2 Amp rapid charging of up to 3 devices simultaneously.
LED light indicates remaining battery capacity.
Battery Cell: Lithium Ion
Battery Capacity: 10.4k
Output Voltage: 4.75V-5.25V
Output Current: 4.1A
Battery Charge Time: 6 hours
Dimensions: 24mm x 80mm x 120mm
CNET I'd prefer it over the many smaller, cheaper, and more versatile battery packs available go »
Making of a Mom Energi 10K is so far one of my favorite portable battery packs to carry around [and] use on the go. go »
BW One Energi 10K is so far one of my favorite portable battery packs to carry around [and] use on the go. go »
Android Headlines Featured as a Top 10 battery pack in Android Headlines go »
7x7SF The TYLT Energi 10K Battery Pack gives you peace of mind when your portable gadgets are running low go »
Huffington Post are among my favorite chargers, period. go »
Tech Bargains: "We found the Energi 10K to be one of the most useful and longest lasting batteries we have ever tested out. 4.5/5" go »