Simple soldering question : vbat on cerberus

I apologize in advance for my newbie soldering question!

What’s the recommanded way to solder a battery to the cerberus mainboard’s vbat pin ? Just use the external extension of the pin 8 of the socket 8 or should I desolder the whole socket and solder it again ?

I tried to solder directly a wire to the pin extension, but nothing sticks on it. I don’t have any rosin flux, is that the reason ?

You can also use Extender module. Easier to solder a wire on extender and not as permanent as soldering wire directly to mainboard.

Flux is king. You need flux.

I would use an Extender module or makebread or the breakout module, and solder onto the big solder pads there.

@ Brett - OK thanks, I’ll buy flux ASAP then.

I’ll consider extender/breakout module only in the last resort : the battery is there to power RTC+crystal offline, so it safest to solder directly to the mainboard to prevent any module removal and losing RTC sync.