It depends on the capacity of the battery (usually given in mAh) not the voltage.
I agree that it all depends on the size of the battery. Let me give you an example. How long does it take to fill a 2oz. shot glass compares to filling a one gallon jug? Obviously the smaller container will fill first. But there is one other factor. If the shot glass is empty and the 1 gal jug is just missing one ounce which will fill first. In this case the one gal jug will top out first.
This is the same story with your battery, but let me add one more factor. Will a 1000 amp charger top out your battery faster than a 10 amp one? This like using a larger hose to fill the shot glass and the jug. At some point as the hose gets larger their will come a point where both containers will be full at the same time.
Finally, when recharging a battery we are causing a chemical reaction to take place and that takes time, we just can't rush the reaction.
So what have we learned. The answer is that there are many variables which will effect the answer you seek, so there is no one set answer for you.
You do not charge a 7.2 volt battery with a 9.6 volt charger period unless you want to ruin the battery. You charge it with a 7.2 volt charger.
No, you cannot charge an 8 volt battery with a 6 volt charger. The voltage of the charger must match the voltage of the battery.
With a charger specifically designed to charge this battery.
A .6 amp charger is a trickle charger. It would take days to charge a dead 12 volt battery with this charger. You need a 10 amp charger which will charge it in a couple of hours.
As long as it is a 12 volt battery you can if you set the charger on low.
No, a 12 volt charger will overcharge a 8 volt battery and destroy it.
I doubt the charger is putting out 30 Amps on a slow charge. need more info on battery and charger.
No, an automobile battery charger outputs 12 Volts. This is far too many volts to charge a 5 Volt battery. You would destroy the 5 Volt battery with this charger.
Charge it with a 12 volt battery charger.
3 hours
It is not recommended to use a 12 volt charger to charge a 14.4 volt battery as the charger may not provide enough voltage to fully charge the battery. Using the correct voltage charger will ensure efficient and safe charging of the battery.
It is not recommended to charge a 6 volt battery with a 12 volt battery charger as it can damage the battery. The higher voltage can overcharge the battery and cause it to overheat. It is important to use the correct charger with the matching voltage to prevent damage to the battery.