My iPhone 8 Refuses to Die: Now It's a Solar-Powered Vision OCR Server

> The phone’s battery health held up reasonably well. After over a year of constant operation, it’s at 76% capacity.

I have an iPhone SE that I've tried keeping plugged in all the time and its battery has turned into a spicy pillow three times, first with Apple replacing the whole device (since they won't touch it with a swollen battery), then using third-party replacement kits.

This isn't going to work for long if the battery is usually at 100%.

My #1 wish for being able to repurpose old phones is to operate without touching the battery, and/or keeping the battery at 50%. Newer Apple phones have an 80% limit option which is an improvement, but I'm not sure how much. And unfortunately the option isn't there on any but the most recent phones, even on up-to-date iOS.

Most of these devices can't run "without touching the battery" because the external supply can't provide the required peak current, so during some CPU burst it would shut off.

I've seen hacks that replace the battery with a supercapacitor though.

> since they won't touch it with a swollen battery

Interesting. I've had a spicy pillow on a 2017 MBP, they fixed the poor thing, and while at it: replaced the cursed keyboard, and left some kind of tape to reinforce the loosened USB-C ports.

Unfortunately, they didn't do the thermal paste - I had to do DIY, which is something I will never touch again. It did pay off though, it's cooler by some 10°C under load, and runs faster too. It's still loved and in everyday use.

Plug your charger to any Homekit-compatible "smart plug," and create a shortcut that turns the the plug on when the battery reaches 45%, and off when it reaches 55%.

This will of course require a Homekit hub.

Couldn't the power management simply throttle the CPU to never go above supplied power in a battery-free mode? Don't they already implement a power threshold for degraded batteries? It seems like that would just be part of the feature I'm asking for, and easy to implement.

It really seems like, if it weren't for the battery part, these phones could run for decades... but right now you have to replace the battery every couple years because it swells when constantly kept at 100% which it is not designed for.

This

It's frustrating that Apple doesn't offer a proper "battery bypass" mode or even let you set charge limits

A timer is sufficient. No need to be precisely 45% or 55%.

I don't believe a battery bypass mode is physically feasible, since the user could be charging the phone with a cheap 5V 1A charger, and yet the peak power consumption of an iPhone could very well exceed that.

I can't imagine that a timer wouldn't quickly drift and either drain it to zero or charge it fully

That's an intriguing idea, I had no idea that was a possibility.

Unfortunately it wouldn't work for my particular usage, which was keeping it plugged into an old but expensive smart speaker as a music player via its lightning port. A smart plug would turn off the speaker along with the phone... But I appreciate the suggestion, as complicated as it is!

it would still work if you used some kind of lighting/audio splitter (yes, that's a thing) into your speaker, but yeah, that's definitely a fringe case