We are almost finished assembling our quadcopter. Now the last part is to connect the battery. As we are using, S500 frame, it comes with a board, where you can connect the battery by soldering the connectors to the board and later just plug the battery while flying the drone. You can use zipties to lock the battery under the body of the copter, as shown in the following figure:
To summarize the connections, let's recap. The BLDC motors will be connected to the four-in-one ESC (or four individual ESCs). The ESCs will be connected to the ArduPilot's output pins (only signal cables, 5V, and ground cables). The power cables of the ESC (or ESCs) will be directly connected to the battery (in our case, we have connected on the body plate first and later used connector pins to be connected to the battery.). The radio and the RC receiver will be connected...