Most of them you don’t have a choice. There are fans that light up when the fan has any power at all. Motherboards have integrated lights. GPUs have internal LEDs…

Sure, you could desolder some of them, but that’s harder.

Googles already been doing this for years.

Pretty sure this is root only. Normal apps don’t have access to the charge controller and I’ve never seen an app that claims to do this without root.

I don’t know why Google hasn’t put this feature directly into Android. It’s honestly one of the biggest pushes away from Pixel devices for me and it’s absolutely silly.

Honestly, this is more bad “charging hygiene” than anything else. I thought this was the case too until like 10 years ago when I learned how Li-on batteries worked, and since then, I’ve had negligible battery deterioration after 3+ year old devices.

The TLDR is don’t charge your phone past ~80% except on rare days you need the extra juice, and by extension, definitely don’t leave your phone on the charger overnight. Most people do exactly that and it absolutely murders your battery health.

If you’re on Android, AccuBattery is helpful with charge alarms and detailed info if you want to learn about it.

If you have a Samsung with the “protect battery” quick option, it’s a god send and makes this all super easy.

Foldables are the only interesting thing to have happened to smartphones in the past like 6-8 years. It’s kind of sad.