Oh lawdy my sweet summah child! Do not rely on battery power anything to keep you warm in the depths of a Maine winter. Get yourself a good winter coat, hats, mittens or gloves, good waterproof BOOTS!!!, and a base layer to wear under your pants ...at least. People mention layers. So that means your coat on top, and a fleece light jacket or hoodie or sweater under that, and a turtleneck or base layer shirt under that. You'll want a base layer under your pants, especially if your going to wear jeans because the wind will blow right through the fabric. Oh and socks. Buy some Darn Tough or Smartwool socks. Good quality wool socks will keep your feet in good shape even if they get wet or sweaty. Cotton socks will feel gross once they get damp. If you can't afford a pair of $20 socks, then always bring a spare set with you. You will be glad after you step into your first slush puddle on your way to work.