Hello people! Fellow user of an old Lenovo laptop.
I too fell into this trap, one day trying upgrading the new version of Windows 11 (version 22H2 in my case)
I also lost a lot of work staff when my laptop suddenly shut down.
Here is the solution that I found for my Lenovo 330 15-ikb.
When the battery was at 0 and my charger was not working at all. I went to a PC store. Asked them to check their cables, to see maybe the deal on old charger that wouldn't let accept electricity.
After their charger met mine laptop, battery started working, then I tried mine again and it also worked.
I rushed home, but after a while my charger refused to work again. Then I started just swapping sockets all around house and trying different ways to connect the charger. While my laptop was on 0 battery, after a while it took charge, I let it rest for a while, and then I opened Windows and deleted that nasty update.
Everything is fine now. Shame on you Windows, thanks for 0 help.