New Battery Drops To Exactly 6% When Laptop Is Shut Down At Below 43% For Some Hours

I'm reaching out because I'm having a persistent issue with the battery on my Dell device  Lattitude e5570 that seems to be occurring across multiple replacement batteries. The problem manifests as follows:

1. Sudden Battery Percentage Drop:

   • When the battery level drops below 43%, if I then power off the device for some hours, when I power it back on the reported battery level is consistently 6%, even though it was higher before powering off.
   • This sudden drop in reported battery percentage does not seem to match the actual battery drain.

2. Consistent 6% Reporting on Reboot:

   • Regardless of the actual remaining battery charge, whenever I power the device back on after a low-battery shutdown, the reported percentage is always exactly 6%.

I've now had to replace the battery on this device once before due to this same issue, and the replacement battery is exhibiting the identical problem. The battery information reported by upower looks healthy, with a full 57Wh design capacity.

This leads me to believe the issue is not with the battery hardware itself, but rather some kind of firmware or software-level problem with how the battery reporting is being handled on this Dell model.

Has anyone else encountered a similar persistent battery percentage reporting problem, even across multiple replacement batteries? I'm hoping the Dell community can provide some insight or guidance on how to properly troubleshoot and resolve this frustrating issue.

Any help would be greatly appreciated. I rely on accurate battery information for my usage, so finding a solution to this problem is important.

Thank you in advance!