The new smart phones can get very hot when watching movies or when used as GPS devices. 120 deg F is the typical thermal safety cutoff. It’s not the battery that causing this heat, it’s the phone’s CPU. They are computers after all, just not equipped with cooling fans.
1. 30 mm 5VDC fan (.21 A).
2. USB cable. Who doesn’t have several of these?
3. Phone back cover. Can get at phone store or online
4. Super glue
5. Electricians tape
6. 5 VDC rechargeable battery with female USB port (1000 mAh shown)
7. USB extension cord (optional)
8. USB car cigarette lighter adaptor (optional)
1. Cut off male end of cord. About 2” inches.
2. Strip wires #1 (red +), #4 (black -) about 1”. Cut off green / white wires.
3. Strip fan wires about 1”
4. Wrap and / or solder wires - red to red, black to black
5. Wrap connected wires with Electrocutions tape. First individually then together to form cord.
6. Super glue cord and USB plug to fan body.
7. Locate where to mount fan and cut 1” dia hole in phone cover. Close is good enough. Just make sure hole isn’t bigger than fan body.
8. Super glue fan to cover. Make sure air movement is away from phone.
For long trips I use a VogDuo 3 port USB adaptor with extension cord to car adaptor. Can keep Phan, phone, and UDB reading light going from 1 USB car cigarette lighter adaptor