iPod mini battery replacement instructions will be available as part of the Apple iPod manual sold with the product and many electronic retailers will provide advice on how to replace these batteries
Use your key in the door.
All rechargeable batteries will lose capacity eventually -- the ones in the iPod mini are no different. Apple offers a service called the "out of warranty battery replacement" that may be of some assistance to you, or you can try searching the internet for "iPod battery replacement service" to find a third party solution. Good luck.
Key backup?
The iPod mini is very tiny it has music and I don't know what else
Use another vehicle to jump start it, or replace the battery, or charge the dead battery with a charger.
No, In a hydroelectric system force of water rotates a dynamo that generates power. The power must be used or stored in a battery. If the battery is dead you cannot store power.
No, the iPod mini only has music, games, contacts, and calendars.
No. There are no mini apps for iPod nano 6th gen
Trying to see what your asking there... Has Apple released the iPod Mini? If that's the question, no, no it hasn't.
ipod nano
It can have a dead battery, is faulty, or needs to be reprogrammed(usually after work was performed or battery changed).