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As the owner of an HTC Evo 4G, I'm quite familiar with the need to recharge my mobile device at least twice a day. But when I'm not commuting to and from CNET's New York offices, locating an accessible outlet can sometimes be a problem.
I tried using third-party extended batteries that made my phone bulkier than it already is, but on top of the additional size I found that after a few months they could never hold the maximum charge they were once capable of.
It seemed like a fitting coincidence that I recently was sent two i.Sound Portable Power Max batteries for review. The mobile chargers come in two sizes, 8,000 mAh and 16,000 mAh, retailing at $90 and $120 respectively.
Each portable charger offers five USB charging ports, an onboard LED battery meter, and a built-in LED flashlight. Also in the box are a protective cloth carrying case and a USB-to-Micro-/Mini-USB cable.
Both Power Max batteries are surprisingly small, with the 8,000 mAh version measuring just 1x3.25x3.5 inches (HWD). The 16,000 mAh Power Max has a wider, 5.75-inch body. They're both lightweight and small enough to fit in any bag and their slick gray and black design is inoffensive.
Obviously the most important detail in our review is whether or not the Power Max works. The short answer is yes, but the long answer is that we can't judge definitively. As a way to assess the Power Max's ability to repower and hold a full charge, we used an iPad 2 as a subject device.
Of course it's tough to make such tests truly accurate without special battery-testing equipment, but we felt a real-world test would suffice.
i.Sound says that the 8,000 mAh Power Max can fully charge an iPad while the 16,000 mAh can fully charge an iPad twice. After topping off the smaller Power Max we attached a fully discharged iPad 2 to it overnight. The next morning, the iPad 2 was 99 percent charged and the Power Max was depleted. Count that as a successful test.
Next we moved on to the larger-capacity Power Max. After an overnight charge, it had fully powered up our iPad 2. We then attached a second depleted iPad and let the Power Max charge it. On the second attempt, the Power Max gave our iPad only 90 percent, but considering there was no way to tell when exactly the first iPad had finished charging, we'll consider this successful as well.
The problem with testing this type of device is that it's tough to tell how the item will do in the long run, as portable chargers are notorious for losing their ability to hold a charge. During our three weeks of testing, we didn't notice the Power Max batteries lose anything.
The only slowdown in charging we did notice was when we attached multiple USB devices at once. Also, while it's great that these items can charge so many devices at once, the space between the USB ports is tiny. Any type of USB dongle with a larger frame will probably cover the port next to it--just something to keep in mind.
Overall we liked these portable power offerings from i.Sound. We can't yet judge how they stand up to long-term wear and tear, so we'll update this review accordingly if we encounter any bumps along the road. As for price, the Power Max rechargers seem to fall in line with other similar items, and can be found online for up to 30 percent off the original retail price.