Why does the iPhone11 battery capacity drop by 3% over a month?

The lithium-polymer battery of a smartphone has a service life. Under normal circumstances, after more than 500 charge and discharge cycles, the capacity of the phone will drop to about 70%. In this case, the battery life of the phone will be obviously insufficient. However, 500 charge-discharge cycles do not refer to 500 charges, but the entire process of mobile phone power from 0 to 100% to 0. Apple mobile phones usually take 2 days to complete a complete charge and discharge cycle under normal conditions. 500 cycles are enough to use the iPhone for 1,000 days, which means that the battery capacity of the iPhone will be reduced to about 70% after about 2 years and 7 months under normal use.

Therefore, the battery capacity of the iPhone 11 drops by 3% a month. According to this schedule, it will be used up to 30% in 10 months. This is obviously abnormal. However, the loss of lithium polymer batteries is not linear, and it may lose 3% in the first month, but it still remains at 97% in the second month. Therefore, it is best to observe the phenomenon that new mobile phones wear out too quickly. If it falls below 80% within 1 year, it may be a battery quality problem. You can go to Apple’s after-sales service to request a new battery replacement for free.
In addition, Apple mobile phone wear and fast charging have little to do with overnight charging. Because the iPhone 11 itself supports the fast charging function, this function has been repeatedly tested by Apple, and normal use of fast charging will not cause the battery to decay quickly. Similarly, the iPhone has a charging protection chip, and when the phone detects that the battery is fully charged, it will stop charging the battery. So under normal circumstances, even charging overnight every day will not cause the battery to quickly decay. However, some netizens’ bad habits can also cause battery consumption. For example, charging while playing a game, in this case, high heat will be generated inside the mobile phone, which will cause the chemical materials inside the battery to fall off from the positive and negative poles, which will shorten the battery life. Also, the battery is used up every time you use the mobile phone, and it is not charged until it is automatically turned off, which will also seriously affect battery life.

In addition, the environment is relatively cold, which will have a certain impact on the battery. This is because in a low-temperature environment, the electrolyte viscosity of lithium ions in the battery will increase, resulting in a slower lithium ion conductivity. Especially when charging at low temperature, lithium ions can easily form lithium dendrites on the negative electrode surface of the battery, resulting in a decrease in battery capacity. Therefore, Apple’s official website clearly states that the iPhone’s operating environment is. When the iPhone detects that the ambient temperature is too low or too high, it will shut down forcibly to protect the battery.

Therefore, when charging, the phone should be placed in a cool, ventilated place to dissipate the heat generated during charging in time. If you must play the game while charging, it is best to use a small fan to blow heat at the phone, and use an air conditioner to lower the indoor temperature. In addition, in the process of using the mobile phone, try to charge it in time when the battery is about 40% left, and do not wait for the battery to automatically shut down and then recharge. In the iOS 13 system, you can also turn on the “optimize battery charging” option, so that every time it is charged to 80%, the phone will enter a trickle charge state, thereby protecting the battery. As the battery capacity of the iPhone 11 is relatively large, as long as you develop good charging habits, the battery of the iPhone 11 is not too problematic for 2 to 3 years. In addition, battery consumption is irreversible. When the capacity is low to a certain extent, battery life can only be guaranteed by replacing the battery. So if you want the iPhone 11 to last longer, you must develop good charging habits.