ELIF: Why would it be better to not charge a phone/car battery to 100%


iOS 13 plans to save battery life by only charging your phone to 80%. It will learn from your schedule and not charge the phone to 100% until it believes the phone is likely to come off the charger soon. This will in some way save the battery life over time? Apparently tesla does something similar.

In: Technology

Because the battery chemistry weakens as max capacity is reached.

Consider a balloon. It has a maximum capacity. The capacity right before it pops. If you inflate the balloon is just this max capacity every time, it wears on the latex. However if you inflate to only 80% of this max capacity, there’s less stretch wear on the latex.

Same principle on battery chemistry. As the state of charge approaches maximum capacity, there’s a resistance to take more charge. If you’re forcing more charge in, it’s going to wear on the battery. 80% is the chosen balance point between having capacity and putting wear on the battery