Brand new MacBook Air M1, only 9 charge cycles but already at 98% maximum capacity (went from 100% to 98% today in just 3 hours). Should I be worried? : r/mac
MacBook battery cycle count and capacity – How-to - 9to5Mac
Find out if it's time to replace your MacBook's battery - CNET
How to keep your MacBook Pro battery healthy for years | AppleInsider
How To Test A MacBook Battery To See If It Needs Replacing And Replace It | Macworld