For sure. All mine are 1x18650 or 1x14500. 2x21700 is for when you mean it.
But if I was hiking across Antarctica, this is probably the headlamp I'd want. It even comes with an extension cable so you can wear the battery box under your parka to keep the batteries warm and happy.
Well in the Antarctica I would want to have some headlamp from this guy : https://luciferlights.net/en/
I own one of his first headlamp called S and recently seen his new designs and they look superb!