This may come as a surprise, but winter and lithium batteries do not play well! Colder temperatures can damage lithium batteries and slow them down.
There's a massive drop in performance between temperatures. The ideal temperature for our lithium batteries' performance is 80F/30C. When the weather goes down to 50F/10C then performance drops by 30%. Anything under 50F/10C and the performance can drop down very dramatically.
Please avoid keeping your scooter outside and make sure to keep it charged regularly, the performance will improve as the weather gets warmer.