alt Hacker NewsAnother problem is the constant charging and discharging of battery while connected to external power. I believe the latest pixels got or will soon get the ability to run directly off the wall when connected to certain chargers.
I would love to see this technology come to all phones. 80% cap might be controversial but I don't think what I am asking for is controversial in the least.
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That's... really not how this works. As a person designing lithium management circuits, you typically have a very small delta-V for top-off charging. We're talking ~0.1V. Once full, the charge circuit disconnects. If the battery is under load or self-discharges below your dV, charging starts back up usually at a very low current. Top-off is also totally optional, it's just a common feature.
Additionally, only the cheapest of cheap garbage phones would behave the way you imply. Charge controllers are readily available from TI et al with battery bypass. When the battery is full, the system runs on external power exclusively, except for the top-off charge.
It's really a pretty standard feature. You can get controllers with and without this, but you'd have to be either extremely cheap or extremely dumb to not use a controller with battery bypass in an application like a phone.
Based on my own testing, my pixel 8 will run on USB. No current fluctuations that would indicate battery cycling, just a constant draw. My previous Samsung also behaves this way.
You're right that cycling the battery this way is bad for them, that's why competent engineers don't.
> Another problem is the constant charging and discharging of battery while connected to external power.
Is that actually the case? Anecdotally, all my devices which spend 99% of their time connected to external power show the least degradation in reported capacity and the best preservation of their original battery life. I'm talking about iPhones, macbooks and hp laptops.
For the latter, I have two basically identical ones, one for work and the other for home (same model number, same generation, same battery p/n). The home one rarely if ever runs on battery, it has something like 50 cycles in 4 years. The battery lasts pretty much as when it was new. The other runs often on battery and it only lasts half as much. I doubt it's a lemon, because it's the standard issue laptop at work, and my colleagues' are in the same boat.
My iphone 14 pro's reported battery health has also degraded much faster than my iphone 7's. I use it much more often on battery than the old one which spent 90% of its time plugged in. But since the devices are different, the comparison isn't as meaningful as with the laptops.