Have you considered something like a CTEK intelligent battery charger and charging it with the battery still connected and in the car?
Battery has never been removed from the car, the IAN 102626 CAR BATTERY CHARGER ULGD 3.8 A1 from Lidi is very like the Ctek, all stages are constant current where one stage of the Ctek has constant voltage, it will not unlike the Ctek return to full output, once it has dropped out of 3 amp rate it will not return on its own, and it will not restart after a power cut, and minimum voltage is 7.3 for a 12 volt battery under that it assumes a 6 volt battery, and it has a built in volt meter, but it is a Smart charger which I know I must use with an AGM/VRLA battery.
As far as I am aware there is nothing the Ctek would do which is any different to Lidi as far as battery care goes, if I have it wrong then all ears.
Thank you
@chris1982 reassuring to realise it can take that long.
After talking to my wife and queried her she says she may have used front screen heating, which would explain why stop start did not work, I was unaware of this when I started post, sorry had I known at the time of starting thread I would not have asked the question.
Gone are the days when you could just bung a Lucas ACR alternator on and it gives full charge all the time!
That was a blast from the past, I remember repairing them, there was a fault with regulators which first caused a non-regular charge patten and then failure, we started using an oscilloscope to monitor charge pattern to reject faulty regulators. Also battery sensed worked OK for years, but machine sensed would burn a hole in centre of the slip rings, and the rectifying pack was poor, the Durite replacement was a lot better with same diodes for field as main output, so we added an extra 3 small diodes and used the original to form a split charging alternator. They were so much better than the old 10 and 11 AC Lucas alternators.
I only found one alternator with current control the old CAV used mainly on Buses with a 440 regulator that had M1 and M2 terminals connected across a lump of steel with saw cuts, which acted as a resistor for regulator and ammeter. However I note now Sterling do a special regulator to stage charge batteries so I suppose that has all changed?
Worked with a few weird alternators including a Delco with 12 and 24 volt outputs used on a Grove crane, crane used 12 volt for all but starting, and the system did not really work, each service we would swap batteries as other wise one would go flat, the relay Bosch used worked better.
Also the French single phase alternators.
Today more interested in the Tonum regulator used on railway engines with the steam turbine generator, dynamos were still used when I started, but things like bucking coils were only found on Buses and like, so since mainly wagons I worked on never got into them.