Been playing my vita a lot lately and it caught the battery glitch ( battery is full but if it drops below 3/4, it reports almost dead) the fix is to open it up and unplug the battery, let the system sit for a minute or so and replug it and re assemble, it worked (I already ordered a new battery yesterday though, guess I’ll have an extra. ) though they say the fix only works for a few months and you have to do it again it apparently only affects the oled model but I managed to do it.
I used a tiny electronics screwdriver that came with my external HD’s case a pair of hospital tweezers that ended up in my go home bag and a guitar center free guitar pick as a spudger. Took maybe 5 minutes all together. And now ol Vita is chugging along with senran kagura.