Symptoms
- BIOS/UEFI screen shows no battery information
- Windows or macOS reports no battery installed
- Laptop only functions while directly plugged in
- Problem persists even after a restart
Likely causes
- CommonLoose or disconnected internal battery connectorEspecially likely after any recent internal work or a drop.
- CommonBattery has failed completely and no longer communicates with the systemA dead battery pack can stop reporting entirely rather than just showing 0%.
- PossibleOutdated BIOS/firmware with a battery detection bugSome firmware updates specifically fix battery recognition issues.
- PossibleBattery has been disconnected by its own safety circuitBatteries can self-disconnect if they detect an internal fault, including swelling.
What to do
- Check for any visible swelling before doing anything else, since a self-disconnected battery for safety reasons should not be forced back into use.
- Check the manufacturer's support site for a BIOS/firmware update that addresses battery detection.
- If the battery is user-removable, power off, remove it, wait 30 seconds, and firmly reseat it.
- Try booting into BIOS/UEFI setup directly to see if the battery shows up there even if the OS doesn't detect it.
- Test with a different known-good battery if available, to isolate whether the issue is the battery or the laptop's circuit.
- If nothing restores detection and there's no visible swelling, the battery has likely failed internally.
Tools and parts
- None required
Replacement laptop batterySearch: “[laptop model] replacement internal battery”
When to call a pro
If you find swelling, stop and have it professionally removed rather than reseating or reinstalling it; otherwise a repair shop can confirm and replace a failed battery.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.