Why is my new battery exhausted after a few mins in the cold? (X-T4)

Hello guys,

I bought my fuji X-T4 in 2020 and I have been using it mainly during summers for my canoe expeditions and in winter while skiing. I never had any issues with it until this winter season.

Every time I go out to ski in the Whistler area, the camera tells me that the battery is exhausted after just a few minutes. (the red empty battery logo flashing before shutting down)

I then bought 2 new fuji batteries and and still tells me the same thing. Weird because this camera and the lens I use are WR (weather resistant) and can technically function to -10 degree celsius. It used to be the case easily the last 2 winters. The batteries were dying a bit faster but at least I could use the camera.

It's annoying because I just can't shoot with it anymore...

I have been reading a lot on the internet over the last few days and I can't find proper information to help me.

Could it be the way I charge them ?(using an extension from the wall socket and then the fuji external charger... which would maybe result in a full battery but with less power)

Could it be corrosion? (I looked at every battery and the camera battery chamber and everything looks super clean)

Could it be moisture in the camera? (Maybe, but the camera works really well in a warm environment, no issues at all)

Anything else ?

Thanks for your time and help

Nick