Answer to "Why my android phone draining while charging?"While i havent solved this issue with my LG V20 on Android 7, i have gathered some interesting data points. When the condition ocurrs, 2 of the 4 cores are static above 1.0 GHz, while the other 2 fluctuate as they all 4 should be. A battery app shows a very low mA charge rate 100 or even negative rates. After a reboot, all 4 cores are back to dynamic fluctuating. The battery app now shows 600 to 900 mA charging. Also worth mentioning, the play store begins updating apps right after the reboot. So either there was a process out there nailing up 2 cores preventing the play store updates from running or the play store service itself could be suspect. Next steps is now to find a cpu core app that shows what threads and app are running during the event.