how to restore battery capaciy
the battery's capacity is significant reduced, how to restore the capacity?
MacBook Air 13″, macOS 11.1
Question marked as
If your battery is getting to the end of its effective life and starting to lose capacity it can be replaced by Apple Service. Use links from Apple Repair and Repair Status Check - Official Apple Support to arrange repair.
Also see 13-inch MacBook Pro (non Touch Bar) Battery Replacement Program - Apple Support which might be relevant, otherwise if it is out of warranty and AppleCare cover the likely repair fees can be found in Mac Repair - Official Apple Support