PROS / The single USB outlet can be switched from the regular 1.x USB to a device with preferred Apple charger settings.
CONS / The smaller-than-average battery has to be charged from a USB outlet if you allow it to drain completely.
VERDICT / While this solar charger is friendly to Apple devices, the undersized battery and low efficiency panels might make this device more trouble than it’s worth.
For a seemingly nondescript device, the Solio BOLT is worth a look. It has its usefulness, but it also has its limitations. The BOLT has two Mono-Si panels that generate 5-volts of electricity for the 2,000 mAh battery. It can be charged from any USB outlet, and is compact enough for easy storage with one panel that rotates over the other. There’s also a single indicator light on the back tells you the device’s mode and charge level.
The panels on this solar cell phone charger are small, and in our testing their output was low enough that the solar charging time that took well over the advertised 10 hours to charge the device’s battery. We attribute this to their combined 160-mAh output. This gives them a lower-than-average output efficiency; however, their configuration is convenient and allows the small design to maximize space.
The Solio BOLT’s 2,000-mAh battery is very undersized compared to others models listed in our best solar phone chargers review. This makes the device better for basic feature phones than anything else, especially considering today’s top smartphones that have an average battery size of over 2,800 mAh.
Despite its size, the BOLT is designed to provide the preferred power output for Apple devices. The battery does compliment most Apple devices up to the iPhone 6 with its 1,810-mAh battery, but is still underpowered for the iPhone 6 Plus. Still, few solar chargers have that kind of output, and only Solio devices offer than in a single port.
The other drawback to this battery is that you will have to immediately begin a solar charging cycle after charging a large device to keep the battery from becoming completely discharged. The BOLT’s battery simply cannot charge from zero on solar power. It must have at least an initial charge for the solar cells to convert energy, otherwise you have to charge it from a USB outlet.
The indicator light on the back is actually a button. It glows green in its normal mode and red when charging from USB. To change to its Apple mode, simply press the button for five seconds, until it turns blue. Checking the battery levels also happens here as tapping the button triggers a series of flashes; each flash after the first indicates an increment of 20 percent. One flash indicates a charging status of 1 percent; the second, 20 percent; the third, 40 percent and so on.
The greatest strength of the BOLT is its ability to change the USB’s normal output to an output that charges at Apple’s preferred rate. The battery is undersized for most modern smartphones, but reasonable for Apple devices up to the iPhone 6, which would take almost a full two hours to charge.