How to make your own battery for drone to you become independent from buying

In this video you will see that I disassembled the battery casing, leaving intact the head where the electronic parts go and the latch or click that holds it to the body of the drone, the battery, in this type of drone it is very complicated, because it is part of the electronics of the drone, that is, it is turned off and on by a button that is in front of the head of the battery. Online I got the connectors for the male and female cables and soldered the female connectors to the head of the battery and soldered the male connectors to the 18650 lithium batteries, put them in series to raise the voltage to 7.4 volts and you only have to connect it to the head of the old battery and exchange it as they are discharged by flights. I went further and broke the top of the drone's battery storage to install a larger battery. Note: Friends, if you are not sure what you are going to do, you better not do it because if you do not know it is a risk and it increases the possibility of spoiling the drone. Thank you.