Some pilots like to solder peripheral things to the main battery connection on the FC or PDB board. And we all know the pitfalls of that:
risk heating the board too much,
battery lead coming loose from the board while soldering peripheral lead, or
not melting the existing battery connection completely resulting in a cold joint on the peripheral.

Here is a suggestion that seems to work good.
Solder a servo pin inside the end of the  battery leads, leaving a little stick out to solder your peripherals to.
See photo:


I tin the pins then stick them into the end of the battery leads,

next, tin the battery leads. This makes for a good joint with the pin and battery lead.

finish up with the permanent soldering to the board.

After it cools i bend the pin backwards until it is above and parallel with the newly soldered battery lead. Do not bend it so far as to come in contact with the battery lead.

This will allow you to solder peripherals to the servo pin very easily and securely without the need to heat up the main battery connection.

You may find it necessary (due to limited space) to bend the pin to the side of the battery leads.

that will give an easy clean soldering. it makes it good for later soldering either.
the pins might give a bit more noise to the system than direct wires with one heatup-solder ball.

i use an additional shrinktube as helping hand, to get many wires to one pad with single heatup;
https://intofpv.com/t-many-wires-to-one-pad