I had the same problem with this tablet.
Original charger didn't work, battery symbol appeared and disappeared again and again.
I fixed it in a quite simple way without opening the device.
I remembered that I got a bad charger, very bad, so bad that a conected smartphone won't even work properly, as there is so much high frequency noise on the 5V-output. By means of this noise this very-very-bad charger put the needed extra-portion of energy into the battery, that the device was able to get behind this critical point at startup, that made it switch off before, and charging could be finished with a proper charger.