Hey guys, I got the same issue, so i'm reopening the thread since I can't find any clue on internet (everything is about fast drain because of lollipop)
My batterie goes instantly to 0% which result in a shut down of the device, it happens randomly, I am still trying to guess what could cause it
Things to know : My phone is rooted, and I did change the screen (which means I touched the inside, and could be the connectors...
But since the guy before had this problem without any of those manipulations..
Here is a screen of the battery. It happens once a day at least if i'm not plugged (otherwise no problem when plugged)