Model: Power Tube 2200
Compatible: Dock Connecting iPods, All iPhones
Mipow Power Tube 2200 Universal Mobile Charger
We strongly support and encourage the development of distinctive-looking -- and -operating -- accessories for Apple's devices, so at first blush, we were intrigued by Power Tube 2200 ($39) from China's Mipow. Apparently certified as an iPod and iPhone battery pack, Power Tube 2200 promises 2200mAh of recharging power in a distinctive aluminum tube shape. And it's regrettably not particularly impressive once you get past how interesting it looks.
Power Tube 2200’s body uses the same sort of hyper-saturated, metallic anodized aluminum that was found in Apple’s iPod nano series up until the polished fifth-generation models came out; you’re given a choice of eight different colors that aren’t apparently designed to match older Apple tones, but look enough like them. Each Power Tube ships with a set of two cables and eleven charging tips for iPods, iPhones, competing cell phones and portable game systems—ten beyond the ones needed for the iPod and iPhone—plus a decent frosted clear plastic box that holds everything.
Whereas Mipow could have really augmented the Power Tube with buttons, lights, and ports, it decided instead to keep things simple. There’s one hole on one side that attaches to two included custom charging cables. You refuel the unit with a cable that includes a full-sized USB plug, then detach the entire cable so that you can attach the second cable, adding an “Apple” connector tip for iPod and iPhone charging. A single light surrounds the connected cable, glowing red when Power Tube is recharging, but not when it’s charging another device. No remaining power indicator, power button, or other frills are included.
And that’s really the primary problem with Power Tube 2200. When it’s used with an iPod, there’s no truly precise way of knowing how much power the device has left, say nothing of the accessory, so everything’s a little fuzzy. How much longer can the Power Tube keep going? It’s unclear. We wound up plugging it into two discharged iPod touches, one fourth-generation and one third-generation. The 2200mAh capacity should have been enough to fully refill the fourth-generation model with at least a half charge to spare for the other one. But after refilling the first iPod, it only had enough juice to make the second one’s “connect to power” screen light up, and not to bring it back to the Home Screen.
That leads us to the other issue. We tried it with an iPhone, and noticed that it was charging very slowly—despite the supposed Made for iPhone certification, it works only at half the iPhone’s peak speed. That 0.5A refueling capability is fine for an iPod, but means that it doesn’t even register as a charging device with the iPad—“Not Charging” appears in the status bar when it’s connected—and leaves it technologically outdated by comparison with the most recent batteries we’ve reviewed.
So the Power Tube 2200 looks nice, but lacks for the sort of status indicators and full-speed iPhone charging we’d expect to find in a good battery accessory these days. It’s an okay option, buoyed more by its nice looks and variety of included charging tips than anything else. By the standards of batteries with metal enclosures, it’s aggressively priced, but we’d sooner recommend options with superior functionality.