DIY Semiconductor Cooling Fan Battery Upgrade
If you are interested in a DIY semiconductor cooling small fan, you may want to read this article.
If you happen to have a semiconductor cooling small fan, but its battery life is not very good, you might come up with the idea of upgrading its battery to improve endurance and discharge performance.
There is a screw under the rubber pad at the bottom. You then need to pry out the white part that contains the button and display. After that, the transparent outer shell can be removed.
Black PCB.
After removing the four corner screws, you can lift up the PCB, and underneath it you will find a blue 18650 battery with no markings. After testing with a load tester, its capacity is only about 1900mAh.
If you happen to have a 21700 battery, it fits perfectly inside.
You then take out a spot welding machine, flatten the original nickel strips, and spot weld them in place.
After powering it on, everything works normally and it feels quite cold, with condensation forming on the surface. Then you reassemble the device.
At the highest cooling mode, the fan draws about 2.2A of current. In theory, this battery can last for more than two hours of continuous use. In real-world usage, it may last even longer, but the maximum mode is quite noisy, so hardly anyone would keep it running at full power for long periods.
