Apple’s $29 iPhone Battery Replacement Program Accelerated, Available From Today

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• Sarah Terra - Saturday, December 30, 2017 - link

  What a scam, seems to me a simple toggle in settings to enable or disable the throttling would cost customers exactly $0.
  
  I bet they make a lot of money battery swaps, which was the plan all along.

• ddrіver - Saturday, December 30, 2017 - link

  The toggle you're talking about would still leave people with severely degraded batteries. How many people want to get the extra performance when it could come at the cost of random reboots? Phones with good batteries aren't slowed down. And the phones that are slowed down have poor batteries anyway so it makes sense that the people would like to change them. It's a good deal.

• basroil - Saturday, December 30, 2017 - link

  ddriver, you're assuming Apple's definition of "severely degraded" matches yours. Most companies state a 20% loss in total charge capacity is "severely degraded", which can happen in as little as a year with iphones (which are often recharged more than once a day from experience). Will a 20% loss in charge cause random reboots? Absolutely NOT, at least not with batteries designed to the maximum current specifications needed to run the damn phone.
  
  Basically, Apple's been using underspecified (low margin, high internal resistance) batteries in their phones and "fixing" the over-current issue with software limits

• shadowjk - Saturday, December 30, 2017 - link

  20% degradation is the battery industry standard for "end of life". From experience I can tell battery performance at that point can be off from original specifications by some orders of magnitude.
  
  Still, you are correct in that if they had been more conservative in their design choices, it wouldn't have been an issue.

• basroil - Saturday, December 30, 2017 - link

  "From experience I can tell battery performance at that point can be off from original specifications by some orders of magnitude."
  
  I don't think you understand what an "order of magnitude" is. Even when a battery is basically dead, the voltage only drops ~25%, and maximum power output (i.e. current at that voltage) drops equivalently down by as much as 50%. That is LESS THAN ONE ORDER OF MAGNITUDE. And this is assuming internal resistance jumps ridiculously high too.
  
  Apple seriously underestimated their margin or, much more likely, purposefully cut a corner in terms of battery specification to claim a much larger capacity than they actually had (since capacity is measured in energy output between a peak voltage and minimum voltage, they just set the min voltage lower than anyone else)

• Jaaap - Saturday, December 30, 2017 - link

  Research Li-ion battery degradation.
  A degraded cold battery will have a much higher internal resistance.

• ddrіver - Sunday, December 31, 2017 - link

  basroil, a severely degraded battery is one that cannot support the device functioning in standard operating conditions. It's not degraded capacity, it's degraded output voltage. Meaning it's not just a few hours less battery time, it's a reboot when power consumption spikes.
  
  When a battery cannot deliver the necessary output in all standard operating conditions then I guess you can call it severely degraded. And I guess apple agrees since they eliminated the spikes by throttling the SoC.
  
  I see most people here wrongly consider just the capacity. But this is meaningless in this case. The measure has nothing to do with the standard 80% capacity at 500 cycles. It's limiting instant power consumption, not extending battery life/autonomy.

• basroil - Sunday, December 31, 2017 - link

  @ddriver Voltage degradation without capacity degradation isn't a thing with Li-ion batteries. In fact, voltage degradation doesn't really exist either, just loss of capacity (which means lower voltage at any given time for the same discharge profile)
  
  Like I said, the issue is high internal resistance and low margins, which means the same current draw drops voltage that much more. Since margins are razor thin to wrongfully state capacity, the battery ends up supplying less voltage than expected

• ddrіver - Monday, January 1, 2018 - link

  Those are not 2 graph lines that go together linearly. Plenty of batteries lose a lot of their capacity but the voltage is still enough to support any peak. Meaning they don't exceed any recommended operating condition. Which is why I'll say it again: the theory has nothing to do with reality until we know what those peaks in SoC power consumption are. It's very likely that the tolerances are a lot lower for Apple's A SoCs so a battery that you'd normally consider works within parameters except for decreased capacity is not enough to power this SoC through peak usage.

• ddrіver - Monday, January 1, 2018 - link

  It's not lack of capacity that kills the phone, it's the inability to provide the necessary voltage. I'm pretty sure there is no term for battery capacity in the power equation, which is what the SoC cares about. The lower capacity is the side effect of not being able to provide the necessary voltage, not the other way around.
  You're drawing an amateurish conclusion that if the battery capacity and voltage both go down in time then capacity is to blame. Hair turns white with age so white hair is the reason for the body deteriorating, no?
  
  Your engine doesn't shut off even if your gas tank shrinks and is too small. It will just run for a shorter time. It turns off when your fuel pump is too weak regardless of capacity. So a battery might as well be a 10.000mAh, when the voltage drops below the required level to support peak power consumption the phone will reboot.
  
  And that depends on the peak power consumption. Which is why I believe that Apple's SoCs trigger much higher spikes than other ARM SoCs. Capacity is irrelevant but the higher spikes trigger reboots earlier than in other phones due to the more powerful SoC exceeding operation conditions.