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Re:A Message to Our Customers about iPhone Batteries and Per... by mikeash on Thursday December 28, 2017 @05:46PM (#16025719)
It’s not about battery life. It’s about not pulling so much current that it suddenly shuts down the entire device. Why do so many people think this is just about making a charge last longer?
Re:A Message to Our Customers about iPhone Batteries and Per... by PhasmaFelis on Thursday December 28, 2017 @06:37PM (#16026104)
The hardware/software behavior could be 100% justified and it still wouldn't excuse the fact that they've hidden it all this time, driving millions of people to buy new phones when they really just needed a new battery.
Re:A Message to Our Customers about iPhone Batteries and Per... by mikeash on Thursday December 28, 2017 @06:53PM (#16026221)
I completely agree, I just want criticism to rest on the facts. There’s far too much useless noise because of this misunderstanding.
Re:A Message to Our Customers about iPhone Batteries and Per... by colejohnson66 on Thursday December 28, 2017 @06:00PM (#16025846)
Because it fits their biases better. Simple as that.
Re:A Message to Our Customers about iPhone Batteries and Per... by blensor on Thursday December 28, 2017 @06:41PM (#16026137)
No. Because it is still about battery life. If it were only about the spurious shutdown then the throttling would happen once in a while, but the reports are about long lasting performance reductions, sometimes down to 50%.

If the battery is in a state where the only solution to prevent sudden shutdowns is to continuosly throttle the system to 50% then my hardware is seriously degraded and someome REALLY needs to tell me that.

Re:A Message to Our Customers about iPhone Batteries and Per... by j_coder on Thursday December 28, 2017 @06:39PM (#16026115)
It is about battery life. This is how the battery should be measured: 100% -> Doesn't charge more 0% -> Do no provide enough voltage/current for safe operation at current power mode.

At 5% the phone could switch (configurable) to extended battery mode (low power mode) and alert the user.

As the battery ages the user will notice better a faster battery discharge (from 100% to 0%) and not the performance slowdown.

Re:A Message to Our Customers about iPhone Batteries and Per... by garmaine on Thursday December 28, 2017 @10:46PM (#16027350)
Your demonstrating the same ignorance the post you’re replying to is complaining about. It is not physically possible for the phone to draw sufficient power off a degraded battery to power it in high performance modes. The battery just doesn’t provide enough electrical current. Apple isn’t stepping back performance on degraded batteries to keep battery life. They are doing it to keep peak current draws at a level the battery can support so that the phone doesn’t hard shutoff when it is receiving insufficient power.
Re:A Message to Our Customers about iPhone Batteries and Per... by ezioamf on Thursday December 28, 2017 @11:47PM (#16027610)
I think you don’t read the comment. If the battery do not have enough power the level would be 0%. The time from 100%(plugged in) to 0% will depend on how degraded is the battery. It is not difficult to understand. You are repeating Apple excuses. Mobile phones had been dealing with degrading batteries for a long time.
Re:A Message to Our Customers about iPhone Batteries and Per... by garmaine on Friday December 29, 2017 @02:17AM (#16028179)
That’s not how batteries work. Degration over time causes a battery to not just store less total capacity on a “full” charge, but also to output less current at the required voltage. The latter is what is preventing the phone from operating under a full load at peak performance without a hard shut off.

The issue is the device shutting off while there is still charge on the battery, not the battery reaching 0% faster.

Re:A Message to Our Customers about iPhone Batteries and Per... by ezioamf on Friday December 29, 2017 @02:39AM (#16028254)
To be clear: 0% would be when current voltage or current mAh level is bellow what the phone needs to operate at maximum capacity.

“Voltage and mAh are two different, but interrelated, things. voltage is a measure of the electrical power a battery can deliver, while mAH (milli-Amp hours) is a measure of how long the battery will maintain usable voltage at a given output current.” https://www.quora.com/How-much-mAh-will-equal-to-1-v

Re:A Message to Our Customers about iPhone Batteries and Per... by j_coder on Friday December 29, 2017 @03:50PM (#16031890)
It is the opposite. Batteries degradation acts as an internal resistance at rest (Rd) that increases over time. There is a second resistance (Rc) that increases as you discharge the battery. As you draw current (I) from the battery the nominal voltage decreases according to Omhs law V = Vn - I*(Rd + Rc).

You can plot different voltage charts as the battery discharges at different stages of degradation (increased Rb). As you know the peak current that phone drains at maximum load you know the minimum voltage it requires to operate. At this minimum voltage you show 0% (or a little higher so the phone can have enough power to gracefully shutdown).

What Apple is doing is slowing down the processor so it drains a smaller current reducing the minimum voltage the phone needs to operate extending the battery life (that also measures the time between 100% to 0%). This way you don't complain that an one year old phone battery is discharging too fast probably because of battery fault or wrong specification. There also a good side effect for Apple of decreased performance perception that induces to premature phone upgrades.