Why does my laptop go out when I unplug the power cord?

My laptop has 95% but when I pull the power cord, does the laptop just go out? What can I do there?

Broken battery? Buy new one.

Could have loose battery contact somewhere in the laptop

Does it go out immediately or let it stand after a few minutes.

Have you ever looked at the settings under energy saving?

I've already looked at everything the laptop goes straight out when I remove the cable