[Johnmed]

I feel your pain.

I recently drove around France in my 8, and too was concerned about getting a flat battery. I took jump leads with me, especially as I had a cool box in the boot. On the ferry out I even left the cool box plugged in by mistake. D'oh!

Thinking of your issue, an intermittent fault, the worst kind in my book, would it be prudent to go one better than jump leads and invest in a jump starter?

While not a fix, at least you would have peace of mind to enjoy France.

I can't imagine what I'd have done if I couldn't start the car with a ferry load of cars behind me!