Windows 11 always freezes or restarts when unplugged

Because it happens right when the charger is removed, I would focus on battery power state, firmware, and power drivers. You already updated BIOS, chipset, and VGA, so next create a battery report with `powercfg /batteryreport` and check design capacity, full charge capacity, and recent critical events. In Lenovo Diagnostics, save the battery test result and attach it by using the camera or image attachment button in the Tech Community reply editor if available; otherwise paste the key lines from the report. Also test one balanced power plan with default settings: open an elevated Command Prompt and run `powercfg -restoredefaultschemes`, then restart. If the laptop still crashes on battery after defaults, it may need Lenovo hardware service even if Windows logs only show Kernel-Power.