At ZP we recommend that you don't solder directly to the SPE, for a couple of reasons:
1) It is time consuming.
2) Some of the pads are made from high temperature pastes (cured at 800 degC) so you can solder to them, whilst others are low temperature inks (cured at 150 degC) so they will be damages if you
try to solder to them, please see adjacent image.
Our advice is to use a connector or cable which we have linked to below.