So my friend gave me this ipod shuffle clone and said it wont start because of not charching. So to see if its still working i connected it to my pc via usb and it detected the ipod (i could copy paste etc). Then after some tinkering i came to know it was the battery problem.Also the battery was rated 3.7v but no current capacity was stated. Then i disconnected the battery from the ipod and used the Arduino's 3.3v as power source and it worked, but frequently kept on restarting(maybe because of low voltage). I could now hear music playing. The question is If i use a battery from a mobile phone which is also rated 3.7v (but larger current rating) will the ipod get damaged? I want to keep the size of the ipod small but making it work is top priority. Looking forward for suggestions.