Hello,
Thanks again for you advice. I checked the pins on the battery holder and one of the pins was sticking (not springing back like the other). I managed to press it down with my hand and took it for a short test ride.
This seems to have sorted it, the battery did not go to empty though it did cut out briefly a few times.
I suspect some dirt or grit may be affecting the pin springing up and down. Is it easy to dismantle the battery holder to clean the pins?
Cheers