What do you do when the battery is exhausted and you can't recharge, and you don't have adequate gear and you're getting cold?
Carry warmer stuff.
People who do a lot of seriously cold outdoor activities learn how to stay warm without electrical gizmos, chemicals or fuels.
Maybe okay for the rank noob out for a night or 2, or for car camping.
Five Basic Principles of Going Lighter (not me... the great Cam Honan of OZ)
“If everybody is thinking alike, then somebody isn't thinking.” ~ Gen. George S Patton
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