The air temperature at higher altitudes tends to be below freezing, thus there is a risk that the batteries in the payload won’t operate effectively. Batteries in cold climates are know to have a higher resistance and will usually become flat very quickly.
I don’t want to risk the chance of my payload loosing power, as it will certainly result in a lost payload.
One solution is to choose batteries that function better in cold climates. According to battery university all batteries are impacted by the cold, however some handle it better than others. Certain NiCad and Lithium Ion Batteries can still operate at -40 Degrees C but at a reduced discharge.
So to attempt to keep the payload at a warmer battery friendly temperature, I am considering some air activated toe warmers, the type you place in your ski boots when in the snow.
I still need to test this functionality to ensure it actually works, and that camera lenses won’t fog, but I;m feeling confident.