Most likely the battery bro, when you change the battery remember to full charge it then completely discharge about 3 times.
Sounds like a battery power retention issue.
Your battery is likely running out of charge cycles. Replace it.
I Will say if you've been leaving your Vita charging over night you just killed the battery. The same thing will happen to a cellphone or tablet.
Sounds like either the battery itself or the charge indicator but in most cases it's the battery. That's how they die naturally.
Is it full when plugged in? If the vita is charging when plugged in then the cord is ok. How old is vita?
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