The newer shimano satelite button sends some kind of order to the battery to power up. The satelite button has it's own battery that provides this command pulse. So turning on the battery with out it could be a little tricky.
But of course, when the battery is connected to the bike, pressing...
Winter is fun! Only real broblem is that the oneup dropper v2.1 gets really slow in freezing temperatures.
EDIT: I will regrease the upper bushing and test if it helps.
Just built up a second hand 2020 Orange P7 29 frame from few spare parts and some new. Uses same drivetrain, brake rotor size and wheel size as my ebike so now I have 3 different tyre/wheel combos to choose from and easy to swap from bike to the other (burly with inserts, fast rolling light and...
I think that switch has a battery. You can verify this by removing the main battery and pressing the button. The button lights up, so there is a battery inside.
Shimano says that the minimum temperature for their system is -10C.
One is not better than the other. It comes down to the user.
Clips are not just about pedaling efficiency, its about constant spinning motion that also benefits E-bikes motors to deliver smooth torque.