Disk utility

Within Disk Utility click "View" and select "Show All Devices" so that the hidden Container appears on the left pane of Disk Utility. Run First Aid on the hidden Container so that First Aid checks all of the APFS volumes. Even if First Aid says everything is "Ok", click "Show Details" and look through the report to see if any unfixed errors are listed. If there are any unfixed errors listed, try running First Aid from Recovery Mode, otherwise you will need to erase the drive and restore from a backup or clone.

Batteries are considered Consumable Products. Over time it will degrade to a point where it needs to be replaced. The usage is normal as the capacity will go up and down all the time and never stay always at 100%. Apple Batteries are rated for 1000 Full Battery Cycles and / or 80% Capacity before needing Evaluation or replacement.

And yes, if the battery has truly dead and running off the Charger / Cable - the computer will run very slow

Running Disk Utilities will not fix the above issue

Start by telling us what you are trying to achieve with Disk Utility. This is a powerful tool that you should rarely use. Badly used it can lead to data loss or your mac no longer booting.

So: what are you trying to do with Disk Utility?

Disregard Double Posting

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