Winter: Can I put my spare battery inside insulated bag with hand warmer?

I will be travelling to somewhere cold that can get to 5 to -10 degrees next year. I live in a tropical country that has no snow so this will be our (me and my hubby) first time.

We have only an Insta 360 Ace pro camera with 3 extra batteries. I read that battery tends to drain faster in winter. I was reading and browsing that people said to put it inside cargo pants or pocket. My pockets will always have hand warmer so was only thinking if we can buy a small insulated pouch and just throw in a small hand warmer and the 3 spare batteries inside. or maybe we will just wrap the hand warmer with a cloth so that it will not have contact with the battery.

What do you think?

https://preview.redd.it/v56e1lmbry6e1.png?width=738&format=png&auto=webp&s=4f4ad333c47f9bfec77dc5aa347ef910f4349f03

https://preview.redd.it/qf5kf53cry6e1.png?width=558&format=png&auto=webp&s=620b88d65922050d2b31cd9c846d8ef25276dd50