:ö: to solder batteries together, solder + of your first battery to the - of your second battery and so on... 'till you are left with one + and one -
it looks like this;
to (+) of your rx or esc --------- switch ----- +[battery1]- *** +[battery2]- *** +[battery3]- *** +[battery4]- ------- to the (- ) of your rx or esc.
¤ +[battery]- = battery with negative and postive poles
¤ *** = points to solder a battery to another battery
¤ -------- = wire
you can use thin strip of conductive metal or electric wire to connect one battery to another.
:TIP:
After you have soldered everything on the battery don't forget to insulate it!, cover those exposed battery terminal, because short circuit will damage your electronics in a sec!
....
-æ