Over the past two years, Apple has made significant efforts to reduce concerns over the audio run time of its portable media players: with the exception of the 12-hour shuffle model, the company’s iPod nanos, videos, and iPhones now play music for between 14 and 24 hours on a single charge. But when it comes to video — or, on iPhone, making calls or accessing the Internet — their batteries run down 4 or 5 times faster. Since there’s no easy way to pop a replacement inside an iPod or iPhone’s body, accessory makers have for years released add-on battery packs that connect using Apple’s standard 30-pin Dock Connector port, typically adding hours if not days of additional run time.
Best known by its APC initials, American Power Conversion has been selling spare batteries and other power accessories for years—typically large items that you’d never expect to toss into a pocket. Roughly iPod-sized and made from glossy black plastic with a single chrome button, the company’s new Mobile Power Pack UPB10 ($70) changes all that. It’s a 10 Watt-hour battery with two USB ports on its top, one a mini-USB port designed to recharge the Lithium-Polymer cell, and the other a full-sized USB port designed to transfer the power stored inside to virtually any USB device. APC provides a wall adapter and USB-to-mini-USB cable to charge UPB10; you provide the iPod, iPhone, or other USB device and a cable to connect it to the battery.
In practice, UPB10’s operation is extremely simple.
Once you’ve recharged it—a 3- to 3.5-hour process—you just plug in the USB-to-Dock Connector cable that came with your iPod or iPhone, and the power starts to flow from one device to the other. The chrome button on its face serves to activate its remaining power indicator, a bar of white LEDs that signals rough 25% marks of residual juice. If there’s power left over when you’re done charging, you can connect it to a second USB device, or keep it around for another go once your first device’s battery is empty again.
Under ideal circumstances, a battery like this one could conceivably add tons of run time to an iPod: the 10 Watt-hour battery has nearly enough power to fully power an iPhone for twice its standard run time, a 60/80GB fifth-generation iPod 3 times, and a nano or 30GB iPod 5 or 6 times. However, unlike some of the batteries out there, UPB10 actually recharges an iPod or iPhone’s battery rather than just serving as an alternate power source, an inefficient process that substantially diminishes its potential run time. Consequently, rather than promising around 85 hours of added audio for a 30GB fifth-generation iPod, APC says that UPB10 will add around 55 hours of audio or 10 hours of video life.
Our testing generally agreed with APC’s findings. We were able to recharge a repeatedly emptied 30GB iPod three times using a completely filled UPB10, which added around 45 hours of audio play time, or 9-10 hours of video play time, under our (and Apple’s) standard testing conditions.
A partially or completely filled full-sized iPod will do better, and a more power-efficient second-generation iPod nano or iPod shuffle will do much better still. By comparison, the iPhone, which uses much more power than iPods and iPod nanos, can fully recharge once off of the UPB10, with a bit of extra juice to spare. On a cross-country trip, this means that the iPhone can be used for extended video viewing on a plane, as well as Internet and calling between flights in the airports, without ending the day empty.
Because of its relative inefficiency and other concerns, using a spare battery pack to recharge your iPod or iPhone isn’t Apple’s preferred way for such a device to work. Rather, Apple recommends—and apparently requires Made for iPod developers to create—devices that tell your iPod to stop draining their own batteries, then drain the spare one first and instead, which would yield longer run times than UPB10 assuming you’re willing to carry both parts around at once. By contrast, APC’s approach fills your iPod or iPhone with more juice, eliminating your need to carry two items in your pocket at once when the recharging is finished.