I think that the battery is fine , but i am going to check it, sorry just everything is going wrong at the moent lol and its just my luck at the moment that it will be the ecu, Im going to see when it hapens again, as when it does the engine just cranks over, if it does I will use the other key to see if it faults with that also. Im going to try and find the obd 2 connector which I think is under the glove box? Ill check to see if there any fault codes.
Cheers