We are in our 3rd winter of owning our 2015 Cayenne S Hybrid. Each winter, the range on a full charge seems to diminish further than the prior year when compared to warmer weather. We typically get 14-16 miles on a full charge in nice weather, and last year saw about 12 miles in the colder weather. This winter it is down to 7-8 miles on a "full" charge, and the dealer keeps telling us it is just what happens when its cold and the battery needs to also power heating etc. Has anyone else seen similar degradation in battery range, or is our experience out of the norm? Thanks!