Well, you don't have to do this...
However if you enjoy doing this, go ahead.
You just don't have to drain it! You can but I wouldn't recomend doing it simply because you only have a limited amount of recharges until the battery will die really quickly.
Disconnect the battery and drain the coolant.
The battery should drain slowly on an iPhone 5s. If the battery was charged correctly the first time. It should take around 10 hours to drain.
No
i normally do, before recharging
It can put out too many volts and destroy the battery but not drain it. The alternator should put out between 13.5 to 16 volts.
No, a bad coil will not drain the battery.
Battery drain would depend on what else is on, for example headlights, courtesy lights, glove box light etcetra. If there is nothing electrical on then there should be no drain.
If you are going to store your vehicle for a long period of time it is a good idea to remove the battery to avoid battery drain.
When the battery light is on. That means your charging system isn't working. You should have your system check. It will drain your battery.
While the car is running the alternator should be recharging the battery faster than stereo can drain it. I suspect you either have a problem with the alternator or its time to get your battery replaced. Until you get it fixed, if you don't turn on the radio, it wont drain your battery :) If it is a high power model, it needs to be wired directly to the battery.
For an iPod Nano-video 3rd generation, it should take twenty-four hours to drain with playing only music, and five hours to drain with playing video.
Yes you sure can. It is a myth that sitting a battery on concrete will drain the battery. It will not drain it at all.