DIY External Power Pack

That’s the thing I made. I’ll edit this post with more detailed information later.

MeterialCountin CNYin USD(6.4:1)Comment
Box100from a box of Hershey’s
Wire100.150.02
Glue stick30.90.14
Battery1203.133.7v/3700mhA
protective circuit for battery13.80.59
Solar pannel16.81.064.5v/78mA
Schottky diode10.50.08ID 5819
booster circuit181.25pre-made, output 5V/500mA
LED10.10.02
Resister10.0202.2k
USB mini port10.280.04
self-lock button10.330.057*7mm
capaciter30.060.011μf
Battery Charger IC191.41MAX1555
bread board140.63
Total price53.948.43
DIY External Power Pack_cost accounting