Help Phone charging slow, not charging, and making vibration noise

[lgoptiumusl9]

Phone: LG Optimus L9

I started getting the "slow charging" notification, but the phone would still charge. Then my phone started to vibrate randomly (the you plugged in charger notification.) Now my phone has the charging sign, but the battery goes down while "charging".

 

[Stannis the Mannis]

It sounds like you may have a faulty battery.