With the same 11,000mAh capacity as uNu's Enerpak Vault, and requiring around the same amount of space, Lenmar's Undead Power Helix External Battery Pack ($100) is most noteworthy for its output capabilities. The three full-sized USB ports can put out a total of 4.4 Amps, meaning you can charge two iPhones and a third- or fourth-generation iPad, all at the same time. It's the first charging accessory of any kind we've seen with that sort of power.…
