Limiting My Laptop Battery to 90% Really Makes a Difference
I've been using it with the charge limit set to 80–90%, and even though it's a 2-year-old model, I've noticed almost no battery degradation. If you always keep your laptop plugged in, be sure to set this up.
7 answers
Agreed—I also use it with an 80% limit, and by the third year the cycle count definitely goes up less.
Well, that's a bit... Isn't the perceived effect of a 90% limit mostly placebo? For lithium-ion, the real problem is leaving it at 100% full in the first place; I don't think the difference between 90 and 80 is that big. In fact, if you look at the cell voltage curve, even at 90% the voltage is already in a fairly high range, so stress remains, and there's a reason manufacturers recommend 80. And the fact that there's hardly any degradation after two years could just as easily mean that the battery on that model was good to begin with or your usage pattern was gentle. It's too early to conclude causation from the single fact that you set a limit.
Got a source? I'd like to see a comparison based on real-world measurements, not manufacturer docs.
Same here. I only ever use mine plugged in at work, and at first I just left it plugged in—then I was shocked when the battery dropped a lot. So now I set a cutoff at 85%, and it really makes a difference. Especially when it lines up with summer heat, leaving it fully charged is genuinely bad for it.