Switch Save Data

Having to change my switch save data over onto an sd card with 16 gbs and it taking MULTIPLE times is gonna be the end of me like... I know this is entirely a first world problem, but it said a half hour for the first change

Shocker! It's now an hour and 40 minutes!

And then I have to change over more data after which I have a feeling will take the same amount of time

I JUST WANTED TO KEEP THE SAVE DATA SO I CAN SEND IT IN FOR FIXING BECAUSE OF THE SHITTY BATTERY

Speaking of, does anyone know why a Nintendo Switch Lite might have it's battery go to absolute shit after less than a year of owning it and me having kept it safely in my backpack while not using it for months? I'm really confused