I don't think that charging a cell phone battery every night hurts the battery. It does not matter how long the battery is being charged. The battery is created for specified period of time and then needs to be changed.
Yes, your can charge the battery with the radio on. But why would you want to do this? It will just take longer to charge with something drawing current from the battery.
Dead battery -will no longer charge.
See this link.
A battery no longer able to provide a chemical reaction to create a charge
When the battery will no longer hold a charge. The guys at the parts store can check it for you.
A battery no longer able to provide a chemical reaction to create a charge
You can safely charge it with a 15 amp charger. You can also charge it with a 1 amp charger it will just take longer. Do not overcharge the battery.
A battery can last from 1 year to many years. You change it when it no longer will start the car or when it no longer will hold a charge.
A good auto battery will hold it's charge for at least 6 months or longer.
You can - but it will take a little longer to charge the higher capacity battery.
battery no longer can store a electrical charge, a charging system failure, a parasitic draw,
At least 24 hours and possibly longer depending on how low the battery was.