Battery Drain while phone is off

[akhenax]

My battery was at 70% last night. I didn't have my charger handy, so I just turned the phone off doing a shutdown. This morning, I boot the phone up, and the battery is at 5%.

Is this a battery issue, a boot up battery drain issue, or a MIUI issue?

 

[illmatic636]

My battery was at 70% last night. I didn't have my charger handy, so I just turned the phone off doing a shutdown. This morning, I boot the phone up, and the battery is at 5%.

Is this a battery issue, a boot up battery drain issue, or a MIUI issue?

On a different note, my phone showed 5% battery left and I rebooted to a 70 % battery left. I think in some cases, our battery meters are a bit wacky. I would attempt a simple reboot next time that happens.