We all know that devices can have their batteries weaken over time if you leave them charging for too long. Why does that happen and why can’t our devices just stop taking in power / cut off right when it’s full?

Question

On my own phone there’s a function where it can stop charging at 95% to protect the battery health. Why can’t it do this at 99.99% and present it as 100%? It would be unnoticeable to users and would prevent the overcharge issue, right?

In: Technology

Answer 1

The thing is, they already do.

What is being presented as 100% isn’t the full potential capacity of the battery. Going any further would be way more damaging and wouldn’t bring any real benefit.

The main issue is that *any* recharging is damaging and the higher you go the damage becomes exponential. So it becomes a tradeoff. Do you want the battery to last a long time until the next recharging or do you want the battery to have a long lifetime?