How Wind-up Cell Phone Chargers Work

Using Wind-up Cell Phone Chargers

Using a wind up cell phone charger is as easy as it looks -- just grab onto the crank and start turning.
Using a wind up cell phone charger is as easy as it looks -- just grab onto the crank and start turning.

So what do you do when your battery on your cell phone runs out and you're forced to use some muscle with your wind-up charger? Fortunately, most chargers are very small and lightweight, even smaller than most cell phones, so they're easy to carry with you and could easily store in a car's glove compartment, a purse or backpack. They typically weigh no more than a couple of ounces.

When your phone needs some extra juice, simply connect the wind-up charger to your cell phone's input. To give the phone's battery its power, you'll need to turn the crank vigorously. Most wind-up charger instructions say to crank at a rate of two revolutions per second, although turning the crank slower or faster is fine and will still provide power to the battery. Depending on the model, you can get 25-30 minutes of extra standby power to a cell phone after just a few minutes of solid cranking. You should only be able to get about 6 minutes of call time from the same amount of exercise, however, since it requires more power to send out signals.

If you have a hands free set like a Bluetooth earpiece, you can even hold the charger and talk at the same time, since charging is a two-handed operation. As long as you keep turning the handle, the power you provide to charge the phone should be greater than the power needed to keep the phone on. This allows you to talk and provide a charge continuously.

What about the different types of inputs on cell phones? Often one of the more frustrating things about losing battery power on your cell phone is when someone else actually has a charger available, but the parts don't fit. Fortunately, many wind-up cell phone chargers come with adapters that fit most phones so you should be able to find the right charge input.

And if the potential to create battery power without the use of an outlet wasn't enough, some models, such as the Sidewinder, even have a built-in LED light that will work after a few seconds of cranking. This feature could be helpful in the event you've lost your phone and there's no other available illumination.

For lots more information on cell phones, batteries and cell phone accessories, see the links below.

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  • Noguchi, Mei, and Ming-Chun Li. "Portable charger." U.S. patent 2007/025053 A1. Dec. 13, 2007. (Jan. 19, 2009) charger&id=cEWjAAAAEBAJ&output=text
  • The Travel Insider. "Sidewinder portable cell phone charger." (Jan. 19, 2009)
  • U.S. Department of Energy. "How wind turbines work." Nov. 30, 2006. (Jan. 19, 2009)
  • "Wind up phone charger keeps you powered." Nov. 7, 2007. (Jan. 19, 2008)