Hi Gareth, I'm happy to give you a day by day account of events.
Saturday 17th July I had my new car 18 days. Travelling around the south circular, at Clifton's roundabout the screen said Battery Discharging. Two minutes later at the Yorkshire grey roundabout the car shut down. After several attempts to restart her the screen said Start car with key. It started and I headed for the dealership not far away. Up to this point there had been no warning lights or messages. At the dealership I was told that the service department was closed and I should try and get the car home (8 miles away)and phone the AA. I got home and rang AA. He could only manage to clear the fault lights and said it would need to go to the dealership. I then had Audi assist who had similar advice. They arranged for the RAC to take the car to the dealership. Same one I got the car from and had been to on the Saturday. Five days later the dealership rang me saying that they had replaced the battery and car was ready to collect. When I got there I was handed the keys and a letter by a receptionist. Happily I had my car back and drove home. Expecting this had been repaired on warranty I was shocked to open the letter and find the bill for a new battery and labour charge. I tried several times to talk to the dealership but could not get past the service reception who said I had damaged the battery by not driving the car enough, apparently modern cars have a lot more electrics and take longer to charge. I contacted Audi uk who said they will contact the dealership on my behalf. I'm still waiting for someone to get back to me.
Regards Paul