Apple publishes a new document on the “Battery Performance of the iPhone”
After the release of beta 2 of iOS 11.3, Apple has posted a new page dedicated to the lithium-ion batteries mounted on the iPhone, explaining how they work, and why it is needed a limitation of the performance and how it is handled all on the iPhone after the update to iOS 11.3.
In this page, we talk about how the process of chemical ageing of a battery affect the power that can be supplied to an iPhone. Apple explains that the voltage drops are the charge of one-off that is “intentional from the point of view of the device“, but “unexpected”user:
The batteries have a complex technology and their performance depend on many variables, which in turn affect the performance of the iPhone. All rechargeable batteries have a limited lifecycle, and therefore with time, the capacity and performance diminish, and may need to be replaced. The ageing of the batteries may lead to changes in the performance of the iPhone. The present information has been created for those who want to learn more about this topic.
The batteries of the iPhone use the lithium-ion technology. Compared to the traditional ones, the lithium-ion battery load faster, last longer and have a high power density. The advantage for you? Greater autonomy in a more compact format. Technology rechargeable lithium-ion battery is currently the best for your device
Apple then begins to explain what it means to optimize battery performance:
With “battery life” means the number of hours for which the device can operate before needing to be recharged. With “battery life” means the period of time expected for the operation of the battery before you need to replace it. The duration and the cycle life of the battery is dependent on usage of the device. In any case, it is always possible to improve the performance of the battery. The cycle life of the battery depends on its “age of chemistry”, which does not correspond to the chronological age, but also takes into account various factors, such as the number of cycles of charging and how it has treated the battery. For example, if you think you do not use your iPhone for a long time, set it up in half. Avoid to reload or leave the iPhone in very warm environments, for example, exposed to the sun for prolonged periods of time.
With the aging chemical, and the ability to hold charge decreases, so you may need to recharge the device more often. You can define the maximum capacity of the battery of its capacity from new. In addition, the battery can decrease its capacity to provide peaks of performance or “peak power”. For the correct operation of the telephone, the electronic components must be able to draw from the instant energy of the battery. A characteristic that affects the provision of instant energy is the impedance of the battery. A battery with high impedance may not be able to provide the energy required by the system. The impedance may increase with the age of battery chemistry. The impedance increases when the battery is low or if it is in a cold environment, but it is a temporary condition. The increase of the impedance will be greater if it is associated with an age chemical high. These characteristics related to battery chemistry are common to all lithium-ion batteries in use in the industry.
The demand for energy in a battery with high impedance will result in a greater reduction of the voltage at the poles of the battery. The electronic components require a minimum voltage to operate. Among these, the internal memory of the device, the power circuits and the battery itself. The energy management system determines whether the battery is capable of delivering such energy and manages loads to keep the device in operation. When the energy management system is no longer able to ensure the operation of the device, the system will shut down to preserve these electronic components. This off, intentional from the point of view of the device, it may be unexpected to the user.
He then enters in detail on how iOS prevents the sudden shut down of your iPhone. In extreme cases, may occur with more frequency, to the point of making the device unreliable or unusable. For iPhone 6, iPhone 6 Plus, iPhone 6s, iPhone 6s Plus, iPhone IF iPhone 7 and iPhone 7 Plus, iOS manages dynamically the peak power to avoid the unexpected shutdown of the device in order to continue to use it. This function of performance management is specific to the iPhone and not about other Apple products.
Specifically, Apple does know that if the need for a performance management more effective, the user may notice effects such as:
There are also many important aspects that do not suffer from the effects of the function of performance management. Among these:
Apple has therefore made it clear that performance management is not about other products, but only the iPhone from 6 to 7/ - Plus. It is confirmed that the problem should not repeat itself on the iPhone 8 and iPhone X with the new upgrade hardware.
The company reminds us that “If you encounter these behaviors, and you want to improve the performance of the device, it may be useful to replace the battery“.
Apple also makes reference to iOS 11.3, explaining the innovations that allow to better manage the battery and performance.
Link to the original article: Apple publishes a new document on the “Battery Performance of the iPhone”