Whay may ipad 3G turn off if not charging

ipad 3G me when charging always reboot back and only put the apple logo and die and come back as it continuously.when charging is terminated, ipad I will not turn on at all. when the charging is done via the PC, the screen just flashes and the screen clears. When connected via itunes can not connect. Why this happen?

whether the battery is in trouble or in another part ?