I went out a few days ago on one of my usual routes and I was wearing my cold wet weather gear as it was 3 degrees, a little misty and a light wind. As the ride progressed the wind picked up and the mist turned to drizzle. Riding in sport mode this 25 mile route would normally use 3 of the 5 battery bars on the display but this time only 2 bars had been used.
I put this down to the fact that the battery was fresh off the charger, I was out riding within 5 minutes of the charge cycle completing so the battery didn't get a chance to cool down (Not that it felt warm)
I’m going to try and time my next charge to finish just before a ride, if that’s not possible I may put the battery in my airing cupboard for an hr before going out !