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0 pointsCoolGuySteve4y ago0 comments

Yeah, every time I post about this somebody on here comes and tells me the Battery Health monitor can’t possibly be lying and that my lived experience must be wrong.

The Battery menu didn’t even present the togggle in the first place because it assessed my battery as healthy. Just like with Rachel here, the Battery menu seems to miss a lot of fucked up batteries. It’s not immaculate.

But if the voltage is not being supplied correctly I would consider that to be degraded “Battery Health”.

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derefr4y ago· 3 in thread

Please don’t conflate “the causal chain I have mentally-modelled to be responsible for my lived experience” with “my lived experience.” I don’t doubt that you saw what you saw; but that doesn’t mean that you’re suddenly uniquely qualified to judge what particular interaction of hardware and software features could have led to you seeing what you saw.

> But if the voltage is not being supplied correctly I would consider that “Battery Health”.

“Battery health” as a feature — i.e. the thing Apple implemented as a response after being sued about not having exposed it to users — only tracks what voltage the battery is putting out, compared to what voltage it would be expected to put out given its lifetime number of discharge cycles and current charge. Which is all the previous, hidden algorithm for “battery health” was basing its decisions on, and so is all that got exposed for manual control.

(As it happens, it’s exactly the same algorithm that leads to a macOS laptop saying “Battery Needs Servicing.”)

This algorithm is meant to detect one thing: whether your battery is like a leaky gas tank, where the amount of voltage * amperage you get out, is less than the amount you put in. Unlike other battery problems that are down to faults in the battery, this problem is an inevitable (100% eventual failure-rate) problem for old, used batteries to suffer, so it’s important to remediate and impractical to offer free replacements for. It’s literally just “wear and tear”, like, say, tyres going bald.

If a battery issue is something that only happens when the CPU boosts i.e. if it’s flaky in a “sometimes perfect, but situationally does the wrong thing” way — then that’s not regular wear-and-tear, but is instead an actual fault in the battery.

The battery health tracking algorithm has no way of knowing† if your battery is faulty. If it could, it would probably say “this battery is broken, please contact Apple for a free replacement.” Because a faulty battery, of exactly the type you described, is a warrantee-covered problem.

† Really, no software can know/predict how a given power source will cope with increased load. This is why we don’t have OS logic in desktop PCs that can convert “a PSU too weak to power your CPU + GPU together at maximum load” into “so they down lock” rather than “your computer spontaneously powers off.”

dundarious4y ago

Your comment applies equally to the Apple techs or the policy they follow, that says Battery Health indicator is a necessary condition for there to be such battery problems, leading to the spurious "it's the logic board" claim. That's the complaint.

AlisdairO4y ago

seems like you could get a reasonable idea by performing a brief workload that should reliably trigger boosting, and see if boosting occurs?

derefr4y ago

A flaky battery is unpredictable; it’s likely that it will boost “sometimes” but not other times. And that “sometimes” will probably not even be able to be locked down to a simple model of having precise conditions where it works or doesn’t.

For example, the battery might be able to boost if the phone is cold, but not if the phone is hot—or vice-versa. It might work to boost for one long boost (i.e. the battery test), but then not be able to do it again for three minutes after that. It might take several tries (pulses of demand) to get it going, and then work. Etc.

Think of a flaky battery like an engine with a bad/clogged carburetor. What pattern of starts does it take to get the engine to turn over? Without seeing the gunk inside the carburetor and doing a turbulent-flow model, you can’t really say.

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