https://wccftech.com/battery-health-management-is-coming-to-macbooks-with-macos-catalina-10-15-5/

Apple is adding a new Battery Health Management feature to MacBooks with macOS Catalina 10.15.5 developer beta. The feature will be released to all MacBook models with Thunderbolt 3 once macOS Catalina 10.15.5 stable update goes live.

Apple says that it is implementing this feature to prolong battery lifespan and improve efficiency by reducing its chemical aging. It sounds familiar because the company had introduced this feature in iPhones sometime back and it was met with criticism due to the company's lack of transparency in how it works. While on iPhones, the performance of the device takes a hit, as battery ages, to prevent unexpected shutdowns, on MacBooks it is implemented differently. It seems to work similarly to the 'Optimized Charging' feature in iPhones.