On my Volvo 855 TDI 1996 with 300.000 km I noticed that the previous owner´s battery died at a young age of 3 years. I bought a new one and found out that it is never fully charged even after 2 hours driving/day. I always could charge it with my external charger. The alternator voltage is indicated 14 Volts on the cover. I consulted the battery manufacturer company MOLL, at which voltage the battery should be fully charged - the answer was 14,2 - 14,4 Volts.
On my Volvo 745 TD 1989 with 375.000 km the charging voltage is around 14,4 Volts, no label any more visible. I bought a battery many years ago, no problem still, when driving enough, the battery is fully charged.
When consulting lists of alternator voltage regulators of companie selling these units for all brands of cars I was surprised to find variations in regulating voltages from 14,0 to 14,5 Volts. Still the batteries and physics are the same in all cars.
2 - Would I take any risk when installing a 14,4 Volt regulator in my 14 Volt alternator? The lights would have a shorter life, I can live with that, just the computer stuff in my car should not die, the airbags should not go off, this would be lethal for the whole car having no more real economic value working still perfect for me.
Franz47