I suspect that you won't do many miles in the lake district. Get a top up in Windermere when you visit, Booths is on the site of the goods yard to the railway station if I remember rightly and 10 minutes walk down to the lake. Both Coniston and Ullswater are pretty and less busy and if you can get over to the west side to Buttermere and Loweswater. Wastwater is dramatic and there is a narrow gauge railway there. You can get a dose of radiation from Sellafield too. I wouldn't worry; with chargers in Keswick, Penrith and Windermere all will be fine. And any chance for a 10 minute top up can add worthwhile miles.