Comment on Is Fast Charging Killing the Battery? A 2-Year Test on 40 Phones
sugar_in_your_tea@sh.itjust.works 3 weeks agoI’m saying when your phone charges to 100%, some manufacturers take that to mean 80% of capacity, whereas others actually charge the battery to 100% of capacity.
BillBurBaggins@lemmy.world 2 weeks ago
Exactly, which is neither a user setting or relatively new. Battery manufacturers have always had to decide what voltage is what state of charge (percent).
The user setting where you limit it to 80% is on top of what the previous commenter was describing
sugar_in_your_tea@sh.itjust.works 2 weeks ago
Sure, if the manufacturer sets it to not charge to the max. I’m saying some manufactured charge to the max by default, hence why that setting is useful.
BillBurBaggins@lemmy.world 2 weeks ago
I think you’re leaning too much into the false assumption that “the max” is some final and definite thing.
Batteries aren’t charged from “empty” to “max”, there is no “max”. They’re charged from one voltage level to another which isn’t in a percentage value. How do you think your phone knows what percentage a battery is at?
sugar_in_your_tea@sh.itjust.works 2 weeks ago
“The max” is the highest voltage the battery can safely store with reasonable losses, and “empty” is the lowest voltage the battery can safely charge from. Or something like that, I’m not a battery engineer. There’s surely a bit of buffer here since users will use it outside of ideal circumstances (ambient temperature, heat dissipation, etc).
Regardless, those numbers come from the battery manufacturer. I’m guessing phone manufacturers add some extra buffer given the properties of the phone (heat generated by electronics, heat dissipation of the case, etc).
None of that has anything to do with what I’m talking about.
The 20-80% range is on top of that and is based on efficiencies in battery tech. That’s the sweet spot of battery longevity, and some phone manufacturers limit charging to the top end and most (all?) warn when you hit the lower bound. But not all manufacturers report 100% when it hits that upper bound of that range. Many do, but not all. Some report 80% and let you bypass it, and some don’t cap that upper bound.