External batteries for the iPhone are nothing new. Almost as soon as the iPhone shipped, there were third-party manufacturers building rechargeable, external battery packs that hooked up to the dock connector and allowed you to recharge the phone on the go. The SolarCharger 906 from iTech is just such a device with an added feature: you don’t even have to have electricity to recharge its battery.

The frame is removable if you want to save space or weight, but it’s an essential accessory if you want to mount the SolarCharger on a window. The suction cups attach to the holes in the frame.

Solar power is one of the major thrusts of the “green revolution,” and on the surface, a solar-rechargeable battery sounds like a great idea. You know, just set the SolarCharger by a sunny window during the day (or under a light that’s otherwise on at night, like a desk lamp), get the battery juiced up, and then you’ve got extra power for your iPhone when you need it. Better yet, hook up a solar panel and power your iPhone from the panel, saving the battery for when you really need it. The problem is that the SolarCharger is extremely reluctant to charge or supply power in anything but bright, direct sunlight.

Most people under the age of 35 probably remember using solar-powered calculators at some point during their school careers. These devices, which were usually simplistic but functional, had a solar panel of less than one square inch in size and worked fine in a classroom, even on a cloudy, dreary day with only artificial lighting high overhead. So you’ll forgive me if I expected the SolarCharger to be able to develop enough current from its nearly five square inches of “high-performance monocrystalline solar panel” to at least charge its internal 1260 mAh lithium-ion battery in reflected or artificial light.

In fairness, iTech does explain in their FAQ, “[the] SolarCharger needs to be placed under direct sunlight” and “[c]louds, smog, tinted window or shadows will impede the sunlight from [powering] the solar panel.” They also warn that fully charging the SolarCharger’s battery using only direct sunlight will take around 22 hours, meaning the best you can realistically hope for in a work day is probably about 1/3 of a full charge (and that only if you live somewhere it’s always sunny, like Arizona, southern California, or possibly Philadelphia). Since I live in Michigan and it’s currently winter, it should go without saying that I was unable to test this claim.

For those of you living in sunnier climes and spending a lot of time in your car, iTech includes a suction-cup mount to attach the SolarCharger to your windshield or other window. Maybe you’ve got a corner office on the south side of the building, or you work in a greenhouse? If you happen to be driving into the sun, this is probably helpful. If you’re driving away from the sun…well, good luck. Even on a bright sunny day a few weeks ago, I was unable to get the SolarCharger to charge from the solar panel unless pointed to within about 30 degrees of the sun.

Finally, the SolarCharger won’t recharge from solar power if its internal battery is totally drained, which isn’t that difficult of a state to get into. Fully discharging the SolarCharger into a nearly dead iPhone will get pretty close, and letting the SolarCharger sit for a few more dreary days will finish it off. Then you’ll have no choice but to hook it up to USB to charge it.

Other than the solar panel, the device is actually quite nice. The SolarCharger ships with a multitude of different charging tips, making it useful with a wide variety of portable electronics, most cell phones and gaming systems, in addition to generic USB and micro-USB adapters. The USB adapter lets you plug in Apple’s standard charging cord, making iPhone or iPod charging a snap (and conveniently allowing iTech to avoid shipping a dock connector-specific adapter at additional cost).

The button on the back can be pressed to show the state of charge of the internal battery. Here the SolarCharger has a full charge. A small red LED below the button illuminates steadily when charging via USB and flashes when charging from solar power.

The 1260 mAh battery capacity is on par with that in the Mophie Juice Pack Air, so when fully charged, the SolarCharger will give a totally flat iPhone (which has a 1400 mAh battery inside) about 80% of a full charge. That’s enough to extend my time away from a charging cable by about a day or so or, if traveling on foot through those portions of the Mojave Desert with AT&T service, maybe indefinitely. A button on the back lets you instantly determine the internal battery’s state of charge, and the same charge indicator LEDs also indicate when the device is charging.

The cable management doesn’t play nice with the USB charging port. As you can see here, the port is easily buried under the SolarCharger’s power cable.

There’s one big drawback to the SolarCharger’s design other than the solar panel, and that’s how it handles USB charging. The plug to charge the SolarCharger via USB is located under the non-removable cable used to charge other devices from the SolarCharger, so in order to charge up the SolarCharger from a computer, you have to deal with the rat’s nest of wire created by unwinding the neatly stored power cable. iTech should have put the charging port on the back of the device or designed the cable management for the power cable not to interfere with it.

Bottom line? Sixty bucks is a lot of money for a device whose major selling point is so limited in real-world use. If all you want is an external battery pack for your iPhone or iPod touch, there are literally dozens of simpler options out there for less than half the money and more than triple the capacity. The versatility is nice if you’ve got a bunch of different devices to charge, but sadly, the solar panel in this application is little more than an expensive gimmick.

Copyright © 2010 Chris Lawson. Reviewing in ATPM is open to anyone. If you’re interested, write to us at reviews@atpm.com.