mike_etape a handwarmer to the back of it
nope that gets way too hot which is also negative for not only battery life but overall battery health, ideally you want it lukewarm
turn off all the extra crap (voice control, wifi, bluetooth, e-stabilization), make sure the rear LCD stays off for as long as possible, and film in only the highest resolution/framerate you need to for your particular shot, not just maxing it out 4k60p all the time which will rip through battery way faster than more reasonable 1080p formats