Simply and easy to make
Step 1: Materials
Electronic part from a old powerbanck,plexy,soldering materials,hot glue,transparent scotch,new slim battery
Step 2: Assembly
Open the old Pb and take only the electronic circuit,change battery(same type on volts) 2200 mA or above
fix all parts on the plexiglas with hot glue and cover with transparent scotch.
use the old cable to charge battery from a USB.this project is for many and différents usage like bluetooth boombox,smartphones,camping lamp(with mini usb led light in my other instructables)....
thank you to watch....