On: PinePhone – KDE Community edition

[josteink]

I believe all those concerns were put to rest once the modularised design of the phone was taken into consideration.

https://news.ycombinator.com/item?id=24596248

[Causality1 → josteink]

Not at all. The specced hardware charge controller has no thermal circuitry and only disables the battery at a 6 amp current draw.

[DoingIsLearning → Causality1]

I'm not a power electronics guy but can a charging circuit realistically be a fire hazard without an initial overcurrent?

It seems like good redundancy to have thermal cut-off but theoretically a fire would have to be preceded by a massive overcurrent anyway, no?

[megous → DoingIsLearning]

Heat can accumulate. You just need to operate near the safety cutoff limit and over the battery spec for long enough.

Anyway, there are layers of protection. More the better.

[Causality1 → DoingIsLearning]

A chip can only detect current that's running through it or a sensor. A breached or shorted cell has a massive overcurrent between two parts of the cell and hence can only be detected by heat

[josteink → Causality1]

> A breached or shorted cell has a massive overcurrent between two parts of the cell and hence can only be detected by heat

But that's not an error which can be caused by badly written software (i.e. like a Linux kernel).

So there's theoreticly no increased risk with running different "home-brew" OS builds on this phone due to software-related aspects of those builds.

[megous → Causality1]

Shorted cell is game over regardless of software, most probably.

[megous → josteink]

"All those concerns" is a bit too much optimistic. There are several concerns, and while there were some ideas put forward, and some patches applied to non-mainline Linux trees, all of those are untested. Values for the NTC were taken from some random datasheet on the internet in the hopes most 10kOhm NTCs have a similar R-T characteristic (they don't), and that the random datasheet I picked matches NTC that's in the battery.

Just to give you a perspective on the level of quality of existing solution.

It's better than before, though.