RE: Picture Tutorial: Swapping out your 10X / 12X batteries
The green thing you are referring to is not a diode. It is a 10amp fuse which can be bought at most electronic stores. It protects against reverse polatity if charger is hooked up wrong.
You are correct that the other thing is somekind of thermal resistor. When I replaced my battery pack with the Eneloop I did not use the thermal resistor.