- #1
ffp
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I want to build a usb charger that works with solar power (and later add a crank dynamo too). The photovoltaic cell will charge rechargeable batteries and they will charge the usb device, like my smartphone.
The smartphone charges with 5V and 1500mAh. I'm planning to use 2 AA batteries 3.4V 3000mAh, but i don't know how sometings will work.
First, what should be the voltage of the solar cell? What will determine how fast does the solar cell charge the batteries, is the current? I don't have much knowledge in batteries...
The smartphone charges with 5V and 1500mAh. I'm planning to use 2 AA batteries 3.4V 3000mAh, but i don't know how sometings will work.
First, what should be the voltage of the solar cell? What will determine how fast does the solar cell charge the batteries, is the current? I don't have much knowledge in batteries...