I think you are spot on tighed1.

I checked the battery with a volt meter at lunch and it was reading 12.3 with the car off which is low as should be 12.6/7 if i am not mistaken. With the car running (dont ask me how or why it started at lunch time but not in the morning) it was measuring 14.4 which shows that the charging system is working ok.

I am going to source a new battery tonight and see what happens when i change them over.