How to charge the iPhone battery in the most correct way in 2021? Teach you charging methods to extend battery life. Mac also works

I believe that when you get an iPhone, iPad or Mac, you will want to know how to charge it to maximize the battery life? What is the best way to charge the battery? Can I charge it all night? Here I will tell you the correct charging method and concept.

The content of the article is a bit rich, but I don’t know if it will be too hard. I try to be simple and clear and give examples to explain. If you want to see the conclusion directly, you can skip the middle of the slide.

|The battery has a memory effect, so it must be charged when it is dead?This concept does not apply anymore

This should be the most common problem. First of all, there are three common batteries.

  • Nickel-cadmium battery (NiCd)
  • Nickel Metal Hydride Battery (NiMH)
  • Lithium ion battery (Li-ion)

Between these three,The severity of the memory effect is Ni-Cd battery> Ni-MH battery> Li-ion battery

The so-called memory effect is that the battery is often recharged without being fully discharged. At this time, the battery will remember the current situation, thinking that its power can only be used up to the present time, resulting in a reduction in battery capacity. For example, imagine a barrel You can hold 100 cc of water, but every time you use only 70 cc, you obviously have 30 cc left. But you fill the bucket with water. Over time, the bucket will mistake you for thinking that you only have 70 cc. can use. This is what it means to think of this bucket as a battery, and the amount of water as electricity.

Correctly charge memory effect

At present, all electronic products of iPhone, iPad, Mac and Apple use lithium-ion batteries, so there is no so-called memory effect problem.Since there is no memory effect, charge it when there is no electricity! But even so, it does not mean that you can use it whatever you want without reservation.

|The behavior to avoid when using lithium-ion batteries

Although the lithium-ion battery used in Apple devices has no memory effect problem, the battery has a lifespan just like other things. In addition, occasionally there must be accidental behaviors that damage the battery, so the lifespan will still vary. The use time drops. As for what conditions can cause lithium-ion battery damage?

Avoid excessive charging and discharging

Lithium-ion batteries are more sensitive to excessive charge and discharge. If you explain a little deeper, you must first know that the structure of the two poles inside the battery can be seen as a grid of separators, and lithium ions will continue to enter and exit these separators in the same direction.

During discharge, the lithium ions inside the battery flow from the negative electrode to the positive electrode. When over-discharged, the negative electrode that releases lithium ions will be excessively worn, and even these separators will be damaged.

When charging, the lithium ions inside the battery flow from the positive electrode to the negative electrode. If it is overcharged, it means that too much lithium ions are plugged into the negative electrode, causing the negative electrode to permanently block the separator.

Correct charging current direction

Therefore, regardless of overcharge or overdischarge, the internal structure of the battery will be damaged.Try not to let the battery maintain too low power or even shut down due to lack of power, which will reduce battery life.

Avoid using batteries at high temperatures

The use of lithium-ion batteries at low temperatures does not have much impact, except that the efficiency will become poor, but not only the efficiency will become poor at high temperatures, sometimes too high temperature may accelerate the chemical reaction in the battery. A large amount of gas is produced inside. These gases are continuously produced but are wrapped by the battery casing. Under strong pressure, there will be a danger of explosion. This must be paid attention to.

Apple officialBattery usage guideIt is also mentioned that 16° to 22° C is the most ideal applicable temperature range. Of course, if it is used outside this periphery, it does not work, but avoid exposing your device to an environment higher than 35° C.

View power consumption program

|Avoid overcharging, should you unplug the power cord immediately after fully charged?Actually not used

As mentioned above, overcharging of lithium-ion batteries can cause permanent damage, so it is reasonable to unplug the battery after fully charged, but Apple’s devices are designed with a charging protection mechanism (in fact, almost most manufacturers will add this mechanism to the product Medium), when the battery is fully charged, it will automatically cut off the current that powers the battery, bypassing the current from the battery and directly brought in by the charging cable to power the device, so again, there is a charging protection mechanism on Apple devices, so you don’t have to worry about overcharging , But please be careful of excessive discharge.

View power consumption program

The “optimized battery” function prevents the phone from always being fully charged

In the past, a lot of information would suggest that you don’t leave your mobile phone to be charged and people go to sleep. The main reason is that there are not so many protection mechanisms in the past. Even with overcharge protection, the battery will not be charged after it is fully charged. After a little bit of discharge, it will be fully charged again. This is repeated to keep the battery at 100%, which is not good for the battery; now Apple has added it to iOS 13, MacOS, Apple Watch and AirPods devicesThe function of “optimize battery” mainly allows the system to learn the user’s usage habits, And adjust the battery charging method according to the situation,Let the battery be charged to 80% as soon as possible, and then it will be trickle-charged, Continue charging to 100% in a slow manner.

Optimize the battery with proper charging

For example, the mobile phone has learned through learning that the user will get up and unplug the charging cable every day between 7:00 and 8:00, then when the phone is charged to 80%, the charging current will be adjusted, and the charging will be as slow as possible until 6:00 and 7:00. The left and right are filled to 100%,To protect the battery from being maintained at 100% for a long time.

Charging correctly, optimizing charging

But if you don’t have the battery optimization function, although there is an overcharge protection mechanism, you don’t need to unplug the charging cable too deliberately when you are fully charged, but it is still recommended not to plug the power cable for too long to avoid charging the battery continuously. Repeat charging with self-discharge.

The “Battery Optimization Function” can be used on devices with iOS/iPadOS 13 and Mac devices with MacOS 15.5.5 and above and Thunderbolt 3. (MacBook Pro 2016 (inclusive) and later and MacBook Air 2018 (inclusive) and later)

|Can I use my mobile phone/notebook while charging?Free, free

As mentioned above, avoid using the battery in a high-temperature environment. However, it is normal for the battery’s temperature to rise during charging, because the voltage at this time is greater than the normal battery discharge, so the high temperature at this time is already in the battery. It is defined as within the range of normal consumption during design, but if you are using apps or mobile games that consume more power at the same time, the temperature of the battery may be higher, and the situation at this time is not as expected during normal design. .

So since the temperature increase during charging is within an acceptable range,Charging and using mobile phones are actuallyis allowed, butIt is recommended not to use mobile games or apps with heavy loads while charging, Because the temperature is too high, even if it does not explode,Still have an impact on battery life.

Charge and use while charging

The above statement is the same even if it is used in MacBook laptops. It is not because the battery configuration of MacBook is relatively large, so there is no need to worry about overcharging or running power-consuming programs during charging. On the contrary, laptops It is more commonly used than mobile phones to execute programs with heavier loads, so the same principle isIf it does not overheat, there is no problem using it while charging, Otherwise, it is recommended to let him charge well when charging. If it is really necessary but the Mac is dead, then use it. (Otherwise, what should I do if I can’t hand over my work…)

|How to know which program consumes more power?

There is a battery health function on the iPhone/iPad to view the apps that consume more power. This article has a detailed introduction

2021 iPhone power consumption reason analysis: iOS 14 quickly runs out of power, power consumption abnormal solution

On Mac, you can click on the battery symbol in the upper right corner, which will display programs that are currently open and consume a lot of power.

View power consumption program

Or use the “Activity Monitor” application to see the CPU load level and power consumption of each software and program.

View power consumption program

|The number of battery cycles is also an important indicator of battery life

First introduce what is the number of battery cycles. When the battery consumes 100% each time as a cycle, the consumption of 100% here means not completely dead, but no matter how many times the discharge time, the total discharge capacity is 100%. An example.

Today I used the battery from 100% to 40%, so I discharged 60%, and then I charged it to 90%.

Tomorrow I will use the battery from 90% to 50%, so I discharged 40%.

A total of 100% of the electricity is used in two days, so this is considered a cycle, so if you only consume 20% of the electricity every day and then recharge it, you will get a battery cycle after 5 days.

Recharge the battery cycle correctly

So why is the number of battery cycles an important indicator?becauseThe battery will be worn out after each battery cycle, which is naturally inevitable (please recognize the facts), In the data given by Apple, the battery cycle times standard for each device is different.

  • iPod: 1,000 times
  • iPad: 1,000 times
  • iPhone: 500 times
  • MacBook: 1,000 times
  • Apple Watch: 1,000 times

If the device is under normal conditions, the number of battery cycles reaches this number, which means that the natural consumption of the battery’s power may have reached 20%, and the battery can be used for only about 80% of the original brand new time. In other words For example, the latest M1 laptop can be used for 20 hours when it is fully charged. Under the same conditions of use, it can only be used for 16 hours when fully charged.

Apple’s suggestion is that you can consider replacing the battery at this time. Of course, if you think that the use time is enough, you can not replace it. After all, after the cycle times are usually exceeded, the warranty period is over one year. Replace it with a 13-inch MacBook Pro. Take the battery as an example, it costs 5,900.

View Mac repair and battery replacement prices and policies

Check the iPhone battery replacement price and policy

Check iPhone battery cycle

The built-in iPhone does not provide a number of battery cycles, but you can use other third-party programs to check or confirm the battery health. As long as it is maintained above 80%, it means that the official recommended battery cycle number has not been exceeded.

How healthy is the battery health of the iPhone in 2021?A guide to battery replacement, warranty, and battery maintenance

Check Mac battery cycle information

On Mac, you can hold down the Option key and click on the “” symbol in the upper left corner to select “System Information”

The “power” item inside can view the number of battery cycles of the computer

Recharge the battery cycle correctly

|So if I don’t use the battery cycle, there will be no loss?Do not be silly

The battery cycle mentioned above will be depleted after each cycle, but the battery cycle is only an indicator to help us judge the current battery condition. It is not the use of this method to cause battery consumption, so even if your computer or mobile phone is bought If the battery is plugged in and not used until the battery is cycled, the battery’s capacity will still drop, and it may drop faster, because this is not the way the battery works under the normal design, just like the above When we say that electricity is always plugged in while sleeping, it is not good to always maintain 100% electricity.

|Can I use a high-power charger?it’s OK

Use more powerful chargers. For example, in the past, they used iPad chargers to charge iPhones. Everyone was worried about whether it would have a bad impact because the power was higher than the iPhone can withstand. But as I said before, Apple’s The safety mechanism has been designed, so when a high-power charger wants to input current to the iPhone, it will consider the iPhone’s endurance and charge at the highest endurable limit.

And this problem is indeed very common, so you don’t need to worry, using high-power chargers for mobile phones or other Apple devices will not affect it.

But still the same sentence, pay attention to the temperature, if the temperature is too high, it will still be bad for the battery, then please change back to the original charger to charge.

Charge the high-power charger correctly


We must clearly recognize that the battery is a consumable, Even in the case of 100% normal use, there will be natural consumption, so don’t pay too much attention to whether the battery is reduced, the consumption is normal, whether it is a MacBook or an iPhone,The battery can be charged at any time when the battery is reduced, no need to worry.

  • Lithium-ion battery has no memory effect and can be charged at any time
  • The three major factors affecting battery life are overcharge, discharge, and high temperature
  • Do not over discharge or use no electricity, try to maintain between 20% to 80, 90%
  • It is recommended not to use an app with a heavy load during charging to avoid excessive temperature
  • Under normal charging and with the “optimized battery” function, there will be less overcharge
  • The battery cycle rate reaches the original factory standard value, which means that 80% of the battery capacity is left. The battery can be replaced according to personal use
  • The use of high-power chargers will not affect, but still pay attention to not too high temperature

Further reading

How much health is left in the iPhone battery to be normal?Consolidation of half-year, one-year and two-year surveys

iPhone battery health questionnaire results

How healthy is the battery health of the iPhone in 2021?A guide to battery replacement, warranty, and battery maintenance

How much is the iPhone battery health maintenance

New macOS features that can extend the life of laptop lithium batteries

macOS battery management