10 ms·

Hi, Battery engineer here at an electric vehicle company. The crux of it is this: when you draw high current from a small battery, the voltage will sag (1). T

Hi, Battery engineer here at an electric vehicle company. The crux of it is this: when you draw high current from a small battery, the voltage will sag (1). The manufacturer has an on-board battery management system that MUST turn off the battery if it goes below a certain voltage threshold. As the battery ages, the sag effect increases significantly, up to 2-3x. Thus, when your phone clearly indicates say 20% battery remaining, if a high load were to be applied, the last 20% would be inaccessible because the battery sag from the spontaneous high load would cause a reboot. Thus, Apple acted in good faith to maximize the battery life on these older devices. The reason is technical, so it's hard to communicate this in a way that all consumers can understand. Yes, they failed at this. Look at all the confusion. (1) Exercise: Suppose no-load 3.4V corresponds to 20% remaining. Suppose that the battery cut-off is set to 3.2V. The battery % is usually derived from a current sensor (coulomb counting), NOT from the measured voltage. But the battery cut-off is a safety feature and needs to be measured hard against the voltage (and the current sensor needs to be ignored due to cumulative error). On a new phone, fully loaded voltage drop = 0.1V On a used phone, fully loaded voltage drop = 0.3V Low-load condition, @20% = 3.4V, OK Full-load condition, @20% = 3.4 - 0.3 = 3.1V, Emergency OFF.

cheeze 6y ago
I agree about the confusion, btu the issue AFAICT is more about the fact that they didn't offer consumers any way to rectify the issue
- sthnblllII 6y ago
  Have the plaintiffs requested some kind of battery notification? Their angle has always been accusing Apple of planned obsolescence, which seems laughable compared to how little long-term support Android phones get.
  - Karunamon 6y ago
    I think they added that around the time the lawsuit was initially filed. You'll get a popup notice when throttling is applied, you have an option to disable throttling (at risk of shutdowns at low charge), and the health metric is exposed in settings now.
  - onion2k 6y ago
    Their angle has always been accusing Apple of planned obsolescence, which seems laughable compared to how little long-term support Android phones get. Apple making phones that last a little longer than Google doesn't mean Apple make products that last. That just means that both Google and Apple are designing products that fail unreasonably quickly.
    - sthnblllII 6y ago
      https://en.wikipedia.org/wiki/IOS_14#Supported_devices https://en.wikipedia.org/wiki/IOS_14#Supported_devices Google isn't the one failing to keep software up to date, its the hardware partners like Samsung. https://www.theverge.com/2020/8/18/21373308/samsung-three-generations-android-updates-upgrades-11-12-13-os https://www.theverge.com/2020/8/18/21373308/samsung-three-ge... > Samsung generally promised two years of updates After 2 years you are at the mercy of zero days and hackers. iOS 14 works on phones that are over 5 years old.
inquirerofsorts 6y ago
> Thus, Apple acted in good faith to maximize the battery life on these older devices. The reason is technical, so it's hard to communicate this in a way that all consumers can understand. Yes, they failed at this. Look at all the confusion. Nothing in your longwinded explanation of battery basics says anything about why I can't go into an Apple store and pay full price for a replacement.
comeonseriously 6y ago
I still read this as they mismatched the CPU and battery size in their obsession with getting iPhones thin.
electro_blah 6y ago
LOL stop defending a shitty company.
gpm 6y ago
The fix for this is simple. Appropriately size the battery when designing and manufacturing the device so that it is still capable of running the device a few years into it's lifetime, instead of a few months. The after the fact fix for this is also to not refuse to fix your defective devices when customers bring them in under warranty claims, and definitely to not lie about them not being defective. You don't make pay out the better part of a billion dollars in settlements and fines because you acted responsibly in a way that is hard to explain to consumers. You pay out a billion dollars in settlements because you broke the law.
- epistasis 6y ago
  Yikes, how many phones did this affect after only a few months? That's an entirely new thing that I hadn't heard before.
  - gpm 6y ago
    Not sure in terms of numbers, you might be able to find it if you dug through the court documents. It's not a rare anecdote though, for instance see this comment currently slightly below this thread: https://news.ycombinator.com/item?id=25144122 https://news.ycombinator.com/item?id=25144122
  - Bud 6y ago
    Approximately zero. And obviously, those would have been covered under warranty. The reason you haven't heard this before is that it didn't happen.
    - gpm 6y ago
      Apple did not consider "my (friends) phone has been throttled because of the battery" as sufficient cause to replace the battery under warranty.
    - darksaints 6y ago
      They weren't covered under my warranty.
yyyk 6y ago
The issue is that Apple knew about the bad batteries* , denied it and discouraged battery replacement, thus leading to increased iPhone sales if users wanted a decent experience - defrauding its own customers. That's not good faith at all. That apologists keep talking about batteries but ignore the real problem smacks of a PR campaign. * We actually don't know if the slowdown was only for bad batteries - that's Apple's version, but it could be that they applied the throttling generally. I'm unaware of any third party who has verified this.
- thirdsun 6y ago
  It's not a bad battery. The degrading performance over time applies to every battery ever sold. Apple decided that keeping your device functional by slightly reducing the performance once the battery is degraded is preferable to randomly shutting your device down. I agree with them.
  - yyyk 6y ago
    The battery isn't good for the entire warranty term. Sure it's bad. Apple decided to lie to users about this, and that just happened to encourage expensive iPhone sales, rather than a cheap battery replacement. I sure hope Apple isn't taking your approach to HW reliability across the board. After all, memory and disk eventually go bad too.
  - La1n 6y ago
    >It's not a bad battery. The degrading performance over time applies to every battery ever sold. It's not a bad banana. Rotting after a while applies to every banana ever sold. Yes it's a natural thing to happen, but it doesnt mean it's not bad.
swiley 6y ago
Most people here are aware of this, at least at the university I went to this was explained in physics class and anyone who's messed with an arduino has experienced it. The problem is that you really need to be able to override things like this. Sometimes users do in fact have a better grasp of the nuances of the particular situation they're in than the programmers do. Sometimes it makes a lot of sense to make this kind of trade off of stability vs performance.
xchip 6y ago
So what? You can still recalibrate the battery estimator and show that the battery each time last less, hiding that was bad faith, and you saying this shows bad fairh too.
- SulfurHexaFluri 6y ago
  You don't know how much time you have less though. You could last 30 minutes on the home screen or you could go flat instantly when you load a 60fps video.
  - xchip 6y ago
    still they could have told people that they could change the battery
Karunamon 6y ago
Again, it's not that Apple didn't violate the laws of physics on their "magical" device, it's that they: 1. Applied the throttling fix silently 2. Denied warranty replacements 3. Wouldn't even replace the battery with cash in hand until after the suit was filed 4. ..leaving people with no good way to have a working device.
- arcticbull 6y ago
  The other option Apple had at their disposal was basically to throttle the device literally all the time so that even when the battery was old the phone would never draw enough current to trigger a brown out condition. Instead what they did was make the most power possible available from the battery at all times, and yes that changed over time. This seems like a much better alternative. I really don’t understand the criticism. The marketing is at issue here. If instead of calling it throttling down when the battery was old they called it boosting up when the battery was new it would have been a best in class feature instead of a $100 million dollar settlement. And yes, at the point where the throttling was taking place, the battery wasn’t defective. That was a completely expected place along the performance curve of a consumable part. So why replace it when it’s working as designed? In my opinion this is the opposite of planned obsolescence, they took devices that would otherwise have to be replaced due to shut downs and allow them to remain in service.
  - marcosdumay 6y ago
    The other option Apple had here was notifying people their battery was bad, not hiding the throttling, and letting people buy new batteries for a reasonable profit.
    - arcticbull 6y ago
      It's not bad though, it's normal, and functioning as expected at that part of the age curve. You can avoid this by reducing performance for the entire time you owned the device so nobody noticed, I guess, but that's all.
coronadisaster 6y ago
> if a high load were to be applied, the last 20% would be inaccessible you are saying that they don't know how to calculate battery percentage left?
salamandars 6y ago
How do these numbers work to be relevant in a phone? Surely without throttling it never draws more than 1A, that's actually enough to cause significant sag like the 0.3V example?
SulfurHexaFluri 6y ago
>The reason is technical, so it's hard to communicate this in a way that all consumers can understand "The battery in your iphone has degraded. Phone performance will be lowered to ensure stability. See an apple store or visit apple.com/battery to have a replacement battery installed" It would have been so easy.
- wlesieutre 6y ago
  For reference, the actual message they added later, which should have been included at the same time as the performance limiting feature: "This iPhone has experience an unexpected shutdown because the battery was unable to deliver the necessary peak power. Performance management has been applied to help prevent this from happening again. [Disable…]" Which still isn't perfect because "performance management" is such a weasely way of saying "reduced performance", but it's a lot better than nothing.
rasz 6y ago
Phone is not an electric car. Capacitors are a feasible solution for momentary high load. Those phones just had tired depleted batteries and the proper thing to do was offer users battery replacement, not lie to their faces while upselling new model.
- udba 6y ago
  A high power workload on a phone might require ~5-10W over 100ms, i.e. ~0.5 joules. At 4V capacitor voltage, you would need ~30mF capacitor. Not likely to fit in a phone. This assumes you’re powering the phone solely off the cap. Even with a battery you’d still need something in the mF range to make up for the battery’s degradation.
  - Dylan16807 6y ago
    The first data sheet I pulled up has an option for 47mF at 4.5V in 20x15x2.3mm of supercap. So it would fit if you really wanted.
    - deleted 6y ago
      [deleted]
    - Dylan16807 6y ago
      Okay the reply got deleted but I already did all this math so I'm going to post anyway. > [only able to use the cap from 4V to 3V] > (C * 1V * 1V)/2 > [you'll need 1000mF] Wrong equation. That's the energy from 0V to 1V. Each incremental volt stores more power than the last. 0V-3V is 9x that amount, and 0V-4V is 16x that amount, so 3V-4V is 7x that amount, and you'll need 140mF. But also it shouldn't be connected directly in parallel to the battery; so I'd think of it more as 4.2V to 2V of supply. That would mean you need 74mF. So put in two and you'll more than hit the target. Even better, if you expect the battery to contribute some, you only need the one.
- aetherspawn 6y ago
  Computers don’t create transient loads that last only a few hundred ms. (The components are already decoupled for that kind of transient). When you open your mail and it has to perform a sync, for example, the transient may last for 10+ seconds and it’s not something you can fix with a supercap. You’d be better off adding more battery at that stage, as a larger battery has lower proportional sag for a given current (coulomb rates). Another thing you can do is size your battery, say 20% larger than you require it, and only charge to 80%. This reduces ageing significantly, BUT consumers would never see this as a feature. They would just complain that the latest Apple phone has 20% less battery than the competitor and is $50 more expensive and heavier than the last model. I’m taking it at a punt that 99% of regular consumers want to change their phone every 2-3 years (to get the latest camera, Face ID or car keys or whatever feature it might be), so that’s what Apple has targeted for the maximum age of their battery. Anything more is making a collective trade-off for the, perhaps, 1% no?
phonon 6y ago
It's Business/Design side vs. Engineering side. Engineering side-- 1. Overprovision the battery 2. Make clear to user if the phone is operating in a degraded mode, and why, and how to fix 3. Make battery replacements cheap and easy Business/Design side-- 1. The phone won't look as sleek, and will cost more! 2. We can't tell consumers their phones aren't perfect! It makes us look bad, and maybe they'll force us to fix it for free! 3. The phone won't look as sleek, and will cost more! 4. Bonus--it encourages users to buy a new phone after a few years!
exabrial 6y ago
The key being here they completely and utterly failed at communication :/
ashtonkem 6y ago
This doesn't actually feel like it's responding to GP, which was actually about how Apple treated the customer and not the realities of batteries.
murukesh_s 6y ago
Then they should show battery at 0% or 1%, so we can go and update the battery not the device itself. Instead they decided to throttle CPU silently. And oh it conveniently timed with new product launches and iOS version releases, so your then flagship device now "feels" sluggish compared to the new models.
- Veen 6y ago
  It either "feels sluggish" or shuts itself down when the power draw peaks. Those are the only two options, and neither looks good compared to a new phone with a new battery.
  - murukesh_s 6y ago
    How about i realize my battery drains "quickly" now, i will go to the store & Apple advices to keep the phone but change the battery for 50 bucks. My device still runs as smooth as it was once the "flagship". But it didn't happen and my device is so slow now (as if the CPU is tired of running) and a new "flagship" is released with 2x the speed and feels so smooth but costs $1000. Hence the lawsuit.
eecc 6y ago
I’m a software developer contractor. By the nature of my work I often have to suffer the “corporate fog”, a sort of induced stupor caused by multiple layers of middle management, generic performance objectives, knowledge loss due to churn and ineffective information management. This drama sounds like a typical corporate misunderstanding: engineers follow technical specs, no written requirements, management doesn’t understand the subtleties - nor do their care for them and they’re busily enough already with all the other tugs. Eventually shit hits home, PR digests and translates into requirements, management gropes along in the fog. There’s no malice, it’s just a large org, and there’s no SJ that agonizes over the details (and even then, he also let big fuckups slip past, remember the iPhone antenna issue)
thaumasiotes 6y ago
> Thus, when your phone clearly indicates say 20% battery remaining, if a high load were to be applied, the last 20% would be inaccessible because the battery sag from the spontaneous high load would cause a reboot. So, I treat the battery readout as basically a scale of "high / medium / low". This works well with the empirical fact that a 20% readout might in fact last longer than a 50% readout. What I don't understand is that most other people seem to treat the percentages as meaningful. They certainly aren't based on "time until a recharge is needed", which is what people want. What are we notionally seeing percentages of?
- jack_h 6y ago
  Disclaimer: I've had to deal with batteries a lot in my career so I'm familiar with their complex nature. I am not an expert though, so I'm sure there are a million more confounding variables that complicate things further. > What I don't understand is that most other people seem to treat the percentages as meaningful. They certainly aren't based on "time until a recharge is needed", which is what people want. What are we notionally seeing percentages of? So yes it kind of is based on "time until recharge". The problem is batteries are more complicated than that. I think a lot of people tend to view batteries as like a power supply that has a certain capacity you consume. This isn't an accurate view. First capacity isn't static, it depends on temperature. Lithium batteries generally have thermal cut-off circuity so temperature compensation is pretty standard to add in. Second batteries have internal resistances which affects its behavior. Internal resistances naturally rise as batteries age, or more accurately go through recharge cycles. This changes voltage sag behavior as GP noted. Third, as GP mentioned, batteries don't supply a constant voltage. A lot of people realize battery voltage drops as a battery is used, which is true in a very simple sense. A cell can have a fully charged open circuit voltage for 4.2, but it quickly goes down to 3.7 where it spends most of its cycle around. Note that I specified an open circuit voltage. The second you apply a load the voltage will drop in relation to the load applied. This voltage sag and the subsequent recovery is not instantaneous either, it takes time to reach equilibrium states. So in essence a battery percentage is simplistically portraying the capacity remaining in a battery, but isn't - nor can't - portray the fact that some of that capacity is unusable depending on loading conditions combined with safety cut-offs to protect the battery. Apple's solution was to change the load so there was less unusable capacity. I'd like to re-iterate that I'm not an expert here. Batteries are complicated electrochemical devices. Edit - Let me illustrate a hypothetical analogy. Let's say you have a car with a fuel tank and a poorly designed fuel pump. You fill up the tank with ten gallons, and start driving. The fuel pump heats up as you press on the accelerator, the harder you accelerate the more it heats up. However the fuel acts as a heat sink for the fuel pump. After driving for a while you have two gallons left. At this point you go full throttle and suddenly the engine cuts out because the thermal protection circuitry on the fuel pump kicked in. Your fuel gauge still reads two gallons, the problem is you simply can't consume it at full throttle because the pump won't operate under those conditions. You can still drive at maybe half throttle though.
KuhlMensch 6y ago
I'd rather they just consumed the battery of my 4 year old iphone 4, until it was useless. What they did was practically make my iphone 4 useless, forcing me to abandon the phone due to an OS upgrade. This single experience re-defined my relationship with Apple. Much more than the butterfly keyboard fiasco. I certainly don't buy the "good faith" invocation.
pjc50 6y ago
Look, you can continue to stan for Apple in the comments if you like, but even they admitted they were in the wrong to the tune of a hundred million dollars. What's the old sales motto again .. "Sometimes the customer is actually right"?
seebetter 6y ago
Using iOS feels like someone developed it without using it ever. The iPhone is the most obtuse and mindless device I’ve ever used. I daisy chain Rune Goldberg-style systems to do basic tasks involving a PDF or large file. Save the PDF to iBooks, oh I can’t export it now let me try the print to PDF trick etc etc. All this seems designed to encourage me to pay more for iCloud or other Apple products. Nothing makes sense, everything’s broken and people still love it.
washadjeffmad 6y ago
The lawsuit wasn't over the characteristics of the known degradation curves of the batteries, but how Apple mishandled this by 1) not acknowledging the performance characteristics to customers with sufficient clarity or notice, depriving them of information required to make a reasonable choice to repair their phones over promoting sales of their newer phones, and 2) denying legitimate battery claims, forcing customers to seek out and pay for aftermarket service and parts in lieu of receiving warranty support. The problem was that engineers up and down the chain could say with complete honesty "this isn't a problem because there's nothing unusual about how these are failing", missing the point entirely that no customer would ever be happy knowing they could have fixed it for free/$45 instead of $1000.
deleted 6y ago
[deleted]
someguydave 6y ago
Apple would not have any of these problems if they provided support for third parties to maintain Apple products.

cheeze 6y ago

I agree about the confusion, btu the issue AFAICT is more about the fact that they didn't offer consumers any way to rectify the issue

sthnblllII 6y ago
Have the plaintiffs requested some kind of battery notification? Their angle has always been accusing Apple of planned obsolescence, which seems laughable compared to how little long-term support Android phones get.
- Karunamon 6y ago
  I think they added that around the time the lawsuit was initially filed. You'll get a popup notice when throttling is applied, you have an option to disable throttling (at risk of shutdowns at low charge), and the health metric is exposed in settings now.
- onion2k 6y ago
  Their angle has always been accusing Apple of planned obsolescence, which seems laughable compared to how little long-term support Android phones get. Apple making phones that last a little longer than Google doesn't mean Apple make products that last. That just means that both Google and Apple are designing products that fail unreasonably quickly.
  - sthnblllII 6y ago
    https://en.wikipedia.org/wiki/IOS_14#Supported_devices https://en.wikipedia.org/wiki/IOS_14#Supported_devices Google isn't the one failing to keep software up to date, its the hardware partners like Samsung. https://www.theverge.com/2020/8/18/21373308/samsung-three-generations-android-updates-upgrades-11-12-13-os https://www.theverge.com/2020/8/18/21373308/samsung-three-ge... > Samsung generally promised two years of updates After 2 years you are at the mercy of zero days and hackers. iOS 14 works on phones that are over 5 years old.

inquirerofsorts 6y ago

> Thus, Apple acted in good faith to maximize the battery life on these older devices. The reason is technical, so it's hard to communicate this in a way that all consumers can understand. Yes, they failed at this. Look at all the confusion. Nothing in your longwinded explanation of battery basics says anything about why I can't go into an Apple store and pay full price for a replacement.

comeonseriously 6y ago

I still read this as they mismatched the CPU and battery size in their obsession with getting iPhones thin.

electro_blah 6y ago

LOL stop defending a shitty company.

gpm 6y ago

The fix for this is simple. Appropriately size the battery when designing and manufacturing the device so that it is still capable of running the device a few years into it's lifetime, instead of a few months. The after the fact fix for this is also to not refuse to fix your defective devices when customers bring them in under warranty claims, and definitely to not lie about them not being defective. You don't make pay out the better part of a billion dollars in settlements and fines because you acted responsibly in a way that is hard to explain to consumers. You pay out a billion dollars in settlements because you broke the law.

epistasis 6y ago
Yikes, how many phones did this affect after only a few months? That's an entirely new thing that I hadn't heard before.
- gpm 6y ago
  Not sure in terms of numbers, you might be able to find it if you dug through the court documents. It's not a rare anecdote though, for instance see this comment currently slightly below this thread: https://news.ycombinator.com/item?id=25144122 https://news.ycombinator.com/item?id=25144122
- Bud 6y ago
  Approximately zero. And obviously, those would have been covered under warranty. The reason you haven't heard this before is that it didn't happen.
  - gpm 6y ago
    Apple did not consider "my (friends) phone has been throttled because of the battery" as sufficient cause to replace the battery under warranty.
  - darksaints 6y ago
    They weren't covered under my warranty.

yyyk 6y ago

The issue is that Apple knew about the bad batteries* , denied it and discouraged battery replacement, thus leading to increased iPhone sales if users wanted a decent experience - defrauding its own customers. That's not good faith at all. That apologists keep talking about batteries but ignore the real problem smacks of a PR campaign. * We actually don't know if the slowdown was only for bad batteries - that's Apple's version, but it could be that they applied the throttling generally. I'm unaware of any third party who has verified this.

thirdsun 6y ago
It's not a bad battery. The degrading performance over time applies to every battery ever sold. Apple decided that keeping your device functional by slightly reducing the performance once the battery is degraded is preferable to randomly shutting your device down. I agree with them.
- yyyk 6y ago
  The battery isn't good for the entire warranty term. Sure it's bad. Apple decided to lie to users about this, and that just happened to encourage expensive iPhone sales, rather than a cheap battery replacement. I sure hope Apple isn't taking your approach to HW reliability across the board. After all, memory and disk eventually go bad too.
- La1n 6y ago
  >It's not a bad battery. The degrading performance over time applies to every battery ever sold. It's not a bad banana. Rotting after a while applies to every banana ever sold. Yes it's a natural thing to happen, but it doesnt mean it's not bad.

swiley 6y ago

Most people here are aware of this, at least at the university I went to this was explained in physics class and anyone who's messed with an arduino has experienced it. The problem is that you really need to be able to override things like this. Sometimes users do in fact have a better grasp of the nuances of the particular situation they're in than the programmers do. Sometimes it makes a lot of sense to make this kind of trade off of stability vs performance.

xchip 6y ago

So what? You can still recalibrate the battery estimator and show that the battery each time last less, hiding that was bad faith, and you saying this shows bad fairh too.

SulfurHexaFluri 6y ago
You don't know how much time you have less though. You could last 30 minutes on the home screen or you could go flat instantly when you load a 60fps video.
- xchip 6y ago
  still they could have told people that they could change the battery

Karunamon 6y ago

Again, it's not that Apple didn't violate the laws of physics on their "magical" device, it's that they: 1. Applied the throttling fix silently 2. Denied warranty replacements 3. Wouldn't even replace the battery with cash in hand until after the suit was filed 4. ..leaving people with no good way to have a working device.

arcticbull 6y ago
The other option Apple had at their disposal was basically to throttle the device literally all the time so that even when the battery was old the phone would never draw enough current to trigger a brown out condition. Instead what they did was make the most power possible available from the battery at all times, and yes that changed over time. This seems like a much better alternative. I really don’t understand the criticism. The marketing is at issue here. If instead of calling it throttling down when the battery was old they called it boosting up when the battery was new it would have been a best in class feature instead of a $100 million dollar settlement. And yes, at the point where the throttling was taking place, the battery wasn’t defective. That was a completely expected place along the performance curve of a consumable part. So why replace it when it’s working as designed? In my opinion this is the opposite of planned obsolescence, they took devices that would otherwise have to be replaced due to shut downs and allow them to remain in service.
- marcosdumay 6y ago
  The other option Apple had here was notifying people their battery was bad, not hiding the throttling, and letting people buy new batteries for a reasonable profit.
  - arcticbull 6y ago
    It's not bad though, it's normal, and functioning as expected at that part of the age curve. You can avoid this by reducing performance for the entire time you owned the device so nobody noticed, I guess, but that's all.

coronadisaster 6y ago

> if a high load were to be applied, the last 20% would be inaccessible you are saying that they don't know how to calculate battery percentage left?

salamandars 6y ago

How do these numbers work to be relevant in a phone? Surely without throttling it never draws more than 1A, that's actually enough to cause significant sag like the 0.3V example?

SulfurHexaFluri 6y ago

>The reason is technical, so it's hard to communicate this in a way that all consumers can understand "The battery in your iphone has degraded. Phone performance will be lowered to ensure stability. See an apple store or visit apple.com/battery to have a replacement battery installed" It would have been so easy.

wlesieutre 6y ago
For reference, the actual message they added later, which should have been included at the same time as the performance limiting feature: "This iPhone has experience an unexpected shutdown because the battery was unable to deliver the necessary peak power. Performance management has been applied to help prevent this from happening again. [Disable…]" Which still isn't perfect because "performance management" is such a weasely way of saying "reduced performance", but it's a lot better than nothing.

rasz 6y ago

Phone is not an electric car. Capacitors are a feasible solution for momentary high load. Those phones just had tired depleted batteries and the proper thing to do was offer users battery replacement, not lie to their faces while upselling new model.

udba 6y ago
A high power workload on a phone might require ~5-10W over 100ms, i.e. ~0.5 joules. At 4V capacitor voltage, you would need ~30mF capacitor. Not likely to fit in a phone. This assumes you’re powering the phone solely off the cap. Even with a battery you’d still need something in the mF range to make up for the battery’s degradation.
- Dylan16807 6y ago
  The first data sheet I pulled up has an option for 47mF at 4.5V in 20x15x2.3mm of supercap. So it would fit if you really wanted.
  - deleted 6y ago
    [deleted]
  - Dylan16807 6y ago
    Okay the reply got deleted but I already did all this math so I'm going to post anyway. > [only able to use the cap from 4V to 3V] > (C * 1V * 1V)/2 > [you'll need 1000mF] Wrong equation. That's the energy from 0V to 1V. Each incremental volt stores more power than the last. 0V-3V is 9x that amount, and 0V-4V is 16x that amount, so 3V-4V is 7x that amount, and you'll need 140mF. But also it shouldn't be connected directly in parallel to the battery; so I'd think of it more as 4.2V to 2V of supply. That would mean you need 74mF. So put in two and you'll more than hit the target. Even better, if you expect the battery to contribute some, you only need the one.
aetherspawn 6y ago
Computers don’t create transient loads that last only a few hundred ms. (The components are already decoupled for that kind of transient). When you open your mail and it has to perform a sync, for example, the transient may last for 10+ seconds and it’s not something you can fix with a supercap. You’d be better off adding more battery at that stage, as a larger battery has lower proportional sag for a given current (coulomb rates). Another thing you can do is size your battery, say 20% larger than you require it, and only charge to 80%. This reduces ageing significantly, BUT consumers would never see this as a feature. They would just complain that the latest Apple phone has 20% less battery than the competitor and is $50 more expensive and heavier than the last model. I’m taking it at a punt that 99% of regular consumers want to change their phone every 2-3 years (to get the latest camera, Face ID or car keys or whatever feature it might be), so that’s what Apple has targeted for the maximum age of their battery. Anything more is making a collective trade-off for the, perhaps, 1% no?

phonon 6y ago

It's Business/Design side vs. Engineering side. Engineering side-- 1. Overprovision the battery 2. Make clear to user if the phone is operating in a degraded mode, and why, and how to fix 3. Make battery replacements cheap and easy Business/Design side-- 1. The phone won't look as sleek, and will cost more! 2. We can't tell consumers their phones aren't perfect! It makes us look bad, and maybe they'll force us to fix it for free! 3. The phone won't look as sleek, and will cost more! 4. Bonus--it encourages users to buy a new phone after a few years!

exabrial 6y ago

The key being here they completely and utterly failed at communication :/

ashtonkem 6y ago

This doesn't actually feel like it's responding to GP, which was actually about how Apple treated the customer and not the realities of batteries.

murukesh_s 6y ago

Then they should show battery at 0% or 1%, so we can go and update the battery not the device itself. Instead they decided to throttle CPU silently. And oh it conveniently timed with new product launches and iOS version releases, so your then flagship device now "feels" sluggish compared to the new models.

Veen 6y ago
It either "feels sluggish" or shuts itself down when the power draw peaks. Those are the only two options, and neither looks good compared to a new phone with a new battery.
- murukesh_s 6y ago
  How about i realize my battery drains "quickly" now, i will go to the store & Apple advices to keep the phone but change the battery for 50 bucks. My device still runs as smooth as it was once the "flagship". But it didn't happen and my device is so slow now (as if the CPU is tired of running) and a new "flagship" is released with 2x the speed and feels so smooth but costs $1000. Hence the lawsuit.

eecc 6y ago

I’m a software developer contractor. By the nature of my work I often have to suffer the “corporate fog”, a sort of induced stupor caused by multiple layers of middle management, generic performance objectives, knowledge loss due to churn and ineffective information management. This drama sounds like a typical corporate misunderstanding: engineers follow technical specs, no written requirements, management doesn’t understand the subtleties - nor do their care for them and they’re busily enough already with all the other tugs. Eventually shit hits home, PR digests and translates into requirements, management gropes along in the fog. There’s no malice, it’s just a large org, and there’s no SJ that agonizes over the details (and even then, he also let big fuckups slip past, remember the iPhone antenna issue)

thaumasiotes 6y ago

> Thus, when your phone clearly indicates say 20% battery remaining, if a high load were to be applied, the last 20% would be inaccessible because the battery sag from the spontaneous high load would cause a reboot. So, I treat the battery readout as basically a scale of "high / medium / low". This works well with the empirical fact that a 20% readout might in fact last longer than a 50% readout. What I don't understand is that most other people seem to treat the percentages as meaningful. They certainly aren't based on "time until a recharge is needed", which is what people want. What are we notionally seeing percentages of?

jack_h 6y ago
Disclaimer: I've had to deal with batteries a lot in my career so I'm familiar with their complex nature. I am not an expert though, so I'm sure there are a million more confounding variables that complicate things further. > What I don't understand is that most other people seem to treat the percentages as meaningful. They certainly aren't based on "time until a recharge is needed", which is what people want. What are we notionally seeing percentages of? So yes it kind of is based on "time until recharge". The problem is batteries are more complicated than that. I think a lot of people tend to view batteries as like a power supply that has a certain capacity you consume. This isn't an accurate view. First capacity isn't static, it depends on temperature. Lithium batteries generally have thermal cut-off circuity so temperature compensation is pretty standard to add in. Second batteries have internal resistances which affects its behavior. Internal resistances naturally rise as batteries age, or more accurately go through recharge cycles. This changes voltage sag behavior as GP noted. Third, as GP mentioned, batteries don't supply a constant voltage. A lot of people realize battery voltage drops as a battery is used, which is true in a very simple sense. A cell can have a fully charged open circuit voltage for 4.2, but it quickly goes down to 3.7 where it spends most of its cycle around. Note that I specified an open circuit voltage. The second you apply a load the voltage will drop in relation to the load applied. This voltage sag and the subsequent recovery is not instantaneous either, it takes time to reach equilibrium states. So in essence a battery percentage is simplistically portraying the capacity remaining in a battery, but isn't - nor can't - portray the fact that some of that capacity is unusable depending on loading conditions combined with safety cut-offs to protect the battery. Apple's solution was to change the load so there was less unusable capacity. I'd like to re-iterate that I'm not an expert here. Batteries are complicated electrochemical devices. Edit - Let me illustrate a hypothetical analogy. Let's say you have a car with a fuel tank and a poorly designed fuel pump. You fill up the tank with ten gallons, and start driving. The fuel pump heats up as you press on the accelerator, the harder you accelerate the more it heats up. However the fuel acts as a heat sink for the fuel pump. After driving for a while you have two gallons left. At this point you go full throttle and suddenly the engine cuts out because the thermal protection circuitry on the fuel pump kicked in. Your fuel gauge still reads two gallons, the problem is you simply can't consume it at full throttle because the pump won't operate under those conditions. You can still drive at maybe half throttle though.

KuhlMensch 6y ago

I'd rather they just consumed the battery of my 4 year old iphone 4, until it was useless. What they did was practically make my iphone 4 useless, forcing me to abandon the phone due to an OS upgrade. This single experience re-defined my relationship with Apple. Much more than the butterfly keyboard fiasco. I certainly don't buy the "good faith" invocation.

pjc50 6y ago

Look, you can continue to stan for Apple in the comments if you like, but even they admitted they were in the wrong to the tune of a hundred million dollars. What's the old sales motto again .. "Sometimes the customer is actually right"?

seebetter 6y ago

Using iOS feels like someone developed it without using it ever. The iPhone is the most obtuse and mindless device I’ve ever used. I daisy chain Rune Goldberg-style systems to do basic tasks involving a PDF or large file. Save the PDF to iBooks, oh I can’t export it now let me try the print to PDF trick etc etc. All this seems designed to encourage me to pay more for iCloud or other Apple products. Nothing makes sense, everything’s broken and people still love it.

washadjeffmad 6y ago

The lawsuit wasn't over the characteristics of the known degradation curves of the batteries, but how Apple mishandled this by 1) not acknowledging the performance characteristics to customers with sufficient clarity or notice, depriving them of information required to make a reasonable choice to repair their phones over promoting sales of their newer phones, and 2) denying legitimate battery claims, forcing customers to seek out and pay for aftermarket service and parts in lieu of receiving warranty support. The problem was that engineers up and down the chain could say with complete honesty "this isn't a problem because there's nothing unusual about how these are failing", missing the point entirely that no customer would ever be happy knowing they could have fixed it for free/$45 instead of $1000.

deleted 6y ago

[deleted]

someguydave 6y ago

Apple would not have any of these problems if they provided support for third parties to maintain Apple products.