poor man's power bank // 18650 battery

I have found this electronic device at chinese supplier of your choice.
It supports charge control and discharge safety switch of lithium cell.
Combine with a 18650 cell from an old laptop computer.
Add an insulation plastic sheet between electronics and cell.
It does not support full 5 Volt, but most cellphones will accept this. I'll reactivate a bluetooth speaker with not working battery.
print colour: check LED colour of your device and print in this colour translucent or natural filame