I'd like to do a home project where I take temperatures inside of my freezer and inside liquids. Liquid-compatibility aside, I'm mostly curious about whether or not anyone can recommend some best practices for the board design. I haven't found any resources online that explain what will happen in applications that are intended for 0C temperatures. I assume the solder joints will contract due to the cold, but does this mean that a surface-mount design will inherently fail? Therefore, should I limit my temperature (and possibly microcontroller) selections to through-hole parts? Is there a better solder formulation to go with, i.e. lead-free or not? Should the pads or through-holes be larger than what's normally found on the IC data sheets in the footprint section?
Any advice or insight would be really appreciated. I'm more than willing to experiment and learn from my mistakes, but if I could get a better head start, that would be nice. :)