Replaced & installed old battery/ Screen flickering

I have an ipod video 5th generation that I've had for about 4 years. Just recently, the ipod stopped working and would not turn on at all. After plugging it in to a wall charger it would not charge, let alone turn on. Then I tried connecting it via USB to my macbook pro and still nothing. I ordered and installed a new battery. When I tried to turn it on the Apple simple came on then it switched off a few seconds later. I then plugged it into my macbook pro and the display on the ipod said "very low battery, connecting" After it sat for a while I unplugged it to see if it was charged and attempted to turn it on. Upon trying to turn it on, the screen began flickering white light and has been doing so ever since. I've done everything to try to get it to boot up but nothing has worked. The flickering white light only stops when I unplug the battery. Any suggestions??