I wonder if from a cost perspective, they actually benefited from doing this. $500 million to make people buy newer iPhones. Wouldn't be surprised if they did the math here to justify the cost of a lawsuit.
How can that be? Replacement batteries are somewhere in the neighbourhood of 1/10 the cost of a new phone.
Not quite accurate. They were preventing the phones from spontaneously shutting down by limiting CPU. Processor spikes can drain older, feebler batteries.
Arguably a “worse is better” experience because although a crash is theoretically to be avoided at all cost because it could result in data loss, this way at least the issue is completely transparent.
The "unexpected shutdown", as Apple called it, was a result of a voltage drop in the battery. Voltage drop occurs when the max current capacity of a battery is exceeded, it has nothing to do with battery age.
Also, when you experience a voltage drop you have generally exceeded the c-rate of the battery and caused some damage which increases it's internal resistance and further reduces the max current capacity of the battery.
The iPhones experiencing "unexpected shutdown" weren't very old, generally a battery is spec'd with a c-rate that takes into account degradation over time. The fact that Apple shipped software to limit the max current draw of the device demonstrates that this wasn't expected behavior AND they were attempting to hide it rather than own up to a defect that might result in a recall.
My understanding is that the flaw was in the batteries. The c-rating was out of spec so every time the device drew max power it would damage the battery causing it's internal resistance to increase.
Once the internal resistance of the battery was high enough, the max power current draw would result in a voltage drop and "unexpected shutdown".
Did a supplier deliver under spec batteries? Did Apple underspec them? Did they know they were underspec and anticipate power management or something would limit exceeding the c-rating? No one knows because Apple refused to acknowledge that it was a defect or take accountability. All we can do is speculate.
I don't like this explanation because the term "life" is loaded and could mean a few different things.
The issue wasn't with the battery's capacity, ability to hold a charge, and not really how long the phone could run before needing to be charged. The issue was that the battery's C-rate was too low for the load.
The C-rate is the rate at which a battery can safely be charged or discharged without damaging it. When you exceed the C-rate you damage the battery and increase it's internal resistance. As a battery's internal resistance increases, the amount of current it can supply decreases. When the amount of current a battery can supply drops below what the load draws, the voltage drops.
This voltage drop would cause what Apple described as "unexpected shutdown". Apple throttled the devices to reduce their maximum current draw, not because the batteries were discharging too quickly but because they were drawing too much current which was further damaging the battery AND causing low voltage drops AND unexpected shutdowns.
It's not clear if the batteries were out underspec, of spec from the supplier, or had an issue which caused them to prematurely degrade. In any cause, they were defective and Apple manipulated the defective devices to hide the issue and when called out offered people discounts rather than issue a recall.