Following widespread criticism for reducing SoC frequency because of battery degradation, Apple announced plans to cut down the price of an out-of-warranty battery replacement for the iPhone 6 and newer models to $29 (from $79) throughout 2018. The battery swap program was expected to kick off early in 2018, but Apple has decided to initiate it immediately in the US, starting December 30. Later on, the company plans to update its iOS in early 2018 to give its customers a visibility of battery wear out and help them to decide whether they need a swap or not.

We expected to need more time to be ready,” Apple said in a statement published by TechCrunch. “But we are happy to offer our customers the lower pricing right away. Initial supplies of some replacement batteries may be limited.

Earlier this month Apple confirmed that it reduces the iPhone SoC frequency, among other things, as its battery capacity depreciates over time in order to avoid unexpected shutdowns from high current draw. The company claims that at times its processors demand a higher peak current than a degraded battery can provide. In particular, as batteries age (or are operated in a low temperature environment), the impedance grows and the ability to supply enough current at a stable voltage drops. Apple’s power management monitors a combination of the iPhone temperature, battery charge, and the battery’s impedance (the company does not say how it can monitor the impedance of a battery). Since all components require certain voltages and currents to operate, in a bid to avoid unexpected shutdowns, iOS reduces the SoC frequency and therefore reduces the performance of the smartphone until the power management IC finds it reasonable.

We have already published two stories covering the Apple battery fiasco, where we covered some additional details on the matter:

While an iPhone is guaranteed to make an emergency call, its aged battery may not provide required performance for all the third-party applications needed. In a bid to remedy the battery situation, Apple offers owners of the iPhone 6, 6S, SE and 7 in the US to install a new battery for $29, starting today. To do so, owners of the said iPhones will have to either send their smartphones to Apple, bring them to the company’s stores, or bring them to an Apple authorized service provider. The final details yet have to be published. Apple says that it usually takes 7-9 days to replace a battery, but if a large number of clients decide to replace their existing units straight away, the service will take longer and shortages of certain battery units may occur. It remains to be seen how Apple deals with its customers in Asia and Europe.

Sometimes early next year Apple intends to update its iOS to give their customers a clear understanding of the health of their iPhone’s batteries. This probably indicates that Apple will continue to lower performance of its SoCs going forward to prevent shutdowns, prolong battery life and guarantee phone operation in case of emergencies for all of its customers. 

Source: TechCrunch

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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.

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