I just finished evaluating of the PedalCell, a new rim dynamo that is designed to charge USB devices while you ride. I was impressed by how much charge it delivered. If you tour with USB-chargeable devices, this dynamo will keep them in electricity without requiring you to plug them into wall outlets.
Here is a quick summary: Every time I rode with the PedalCell, my iPhone ended up with more power at the end of the ride than when I started, no matter what apps I ran on it or how long I rode. My estimate is that it provided a 20% charge per hour of riding (at 10 MPH/16 KPH) to a new iPhone 12.
I written up my findings in
a detailed review of the device for those who want more information, including photos and numbers.
