Smartphone owners Samsung often face a situation where the device begins to discharge faster than after purchase. This is a natural process of degradation of chemical elements inside lithium-ion battery. However, in order to understand how critical the wear is and whether it’s time to think about replacement, it is necessary to obtain accurate digital data about the current state of the power source.
Mobile device manufacturers rarely display information about the actual remaining battery life on the main settings screen. Instead, the user is greeted only with general statistics of charge consumption over the past 24 hours. For in-depth diagnostics of capacity, measured in milliamp-hours (mAh), specific methods are required, ranging from simple engineering codes to the use of a computer.
In this guide, we will analyze all the available methods for checking the battery status on smartphones Galaxy. You'll learn how to interpret the data obtained and which tools will give the most accurate results without having to disassemble the device.
Using Samsung's built-in service menu
The fastest way to access technical information about the battery is to use the hidden engineering menu. In smartphones Samsung it is available through the standard “Phone” application and does not require the installation of third-party software. This method is safe because it only allows you to view data, but not change critical system settings.
To enter the diagnostic mode, you must open the dialer and enter a special combination of characters. After entering the last digit, the menu should open automatically. If this does not happen, perhaps your firmware or region of use blocks this functionality, which occurs on some models for certain markets.
⚠️ Attention: Do not press the “Test” or “Start” buttons in sections whose purpose you do not know. Uncontrolled launch of tests can lead to rebooting the device or resetting the calibration of the sensors.
In the menu that opens ServiceMode you should select the section associated with the battery. Usually it is called BatteryStatus or located in the subsection Device Information. This displays the current charge level, voltage and most importantly the health status of the battery. The system may show the value Good (Good) or indicate the need for replacement.
What to do if the code does not work?
If the combination #0228# does not open the menu, try the code #9900#. On some models with the One UI shell, access to the full service menu is limited, and only basic information about voltage and charge level is displayed without capacity data.
It is worth noting that the built-in menu does not always display the exact capacity figure in mAh. Most often it gives a qualitative assessment of the condition. To get specific numbers on how many milliamp hours are left from the factory 4000 or 5000 mAh, you will need other methods described below.
Checking status through device settings
Starting with the update to One UI, Samsung has added a battery health monitoring feature right into the standard settings menu. This is the most user-friendly method that does not require technical knowledge. However, this option appeared relatively recently and is not available on all smartphone models.
To find this information, go to the section Settings → Device maintenance → Diagnostics. In the list of tests, select item Battery status. The system will conduct a quick analysis and give a verdict: “Good”, “Requires replacement” or “Bad”. The number of charge cycles can also be displayed here if the device model supports this function programmatically.
If there is no “Diagnostics” item in the menu, use the “Samsung Members” application, which is preinstalled on all official brand devices. There is a similar diagnostics section.
An alternative way is through the app Samsung Members. Launch it, go to the Support tab and select Phone Diagnostics. Select battery test. This method is convenient because the application is officially supported by the manufacturer and is regularly updated, ensuring correct operation even on new models of the series Galaxy S and A.
Unfortunately, the standard settings often hide the exact numerical value of the capacity. They are focused on informing the user about critical wear, rather than providing data for enthusiasts. If you need a figure “down to the last milliampere,” this method may not be informative enough.
Use of third-party applications for diagnostics
When the built-in tools are not enough, specialized utilities from the store come to the rescue. Google Play. These applications read system logs and kernel configuration files to provide detailed statistics. The most popular and reliable tool is considered AccuBattery.
The operating principle of such apps is based on an analysis of the charging process. The app does not know the exact capacity of your battery initially. It calculates it by comparing the amount of energy that went into the battery (in mAh) with the percentage change in charge level. Therefore, to obtain accurate data, you need to use the application for several days.
- 🔋 AccuBattery: Shows estimated capacity, wear rate and temperature in real time.
- 📊 Ampere: Measures charging and discharging current, helps identify problems with the power controller.
- 🛠️ Battery Info: Provides technical data: voltage, manufacturing technology and health level.
It is important to understand that the readings of third-party apps are calculated. They depend on the accuracy of the system fuel sensor (Fuel Gauge) inside the smartphone. If the battery controller is faulty or not working correctly, the application will show erroneous data. To improve accuracy, it is recommended to run several full charge cycles from 0% to 100% with the app connected.
⚠️ Warning: Avoid apps with names like “Battery Saver” or “Clean Master” that promise to increase capacity. It is impossible to physically increase the number of chemical elements in a battery using software. Such apps only close background processes.
After installation AccuBattery let it run in the background for at least 3-4 charging cycles. Then go to the Health tab. You will see two numbers: “Calculated capacity” and “Design capacity”. The difference between them will show the real wear percentage of your battery Samsung.
Obtaining accurate data through ADB and computer
The most professional and accurate method of obtaining information about the battery is using USB debugging and interface ADB (Android Debug Bridge). This method allows you to request data directly from the power controller, bypassing the graphical interface and possible errors of third-party applications.
First, you need to activate the developer mode on your smartphone. Go to Settings → About phone → Software information and quickly click 7 times on the “Build number” item. After this, a new section “For Developers” will appear in the main settings menu. Turn on the item USB debugging.
☑️ Preparing for ADB connection
Connect your smartphone to the computer and open the command line in the folder with ADB utilities. Enter a command to test communication with the device. If everything is configured correctly, you will see the serial number of your device. Next, you need to enter a command to display information about the battery:
adb shell dumpsys batterystatsThe output of this command will contain a lot of text. Look for lines containing Estimated capacity or Current capacity. The command adb shell cat /sys/class/power_supply/battery/capacitycan also be useful, although the path to the file may vary depending on the processor model and version of Android.
This method requires some technical training, but it provides “raw” data that is closest to the truth. If you are planning a battery calibration or battery replacement, the data from ADB will be your main guide in making decisions.
The ADB command line provides access to system logs that are not visible to ordinary applications, making this method the standard of accuracy for diagnostics.
Analysis of physical characteristics and markings
Sometimes Software methods may fail due to firmware errors or controller resets. In such cases, it is worth referring to the physical markings of the battery itself. On most modern smartphones Samsung the battery is non-removable, but its model and nominal capacity are indicated on the case or in the documentation.
Knowing the battery model (for example, EB-BG998ABY), you can find its specification on the Internet. Manufacturers always indicate Nominal capacity (typical capacity) and the minimum guaranteed capacity (rated capacity). Usually the first number is slightly higher than the second. For example, 5000 mAh (typ.) and 4900 mAh (min.).
| Samsung model | Battery model | Nominal capacity | Min. capacity |
|---|---|---|---|
| Galaxy S21 Ultra | EB-BG998ABY | 5000 mAh | 4880 mAh |
| Galaxy A52 | EB-BA525ABY | 4500 mAh | 4370 mAh |
| Galaxy Note 20 | EB-BN981ABY | 4300 mAh | 4170 mAh |
| Galaxy Z Flip 3 | EB-BF711ABY | 3300 mAh | 3200 mAh |
By comparing current indicators from applications with the factory minimum capacity, you can understand the degree of degradation. If the app shows 3500 mAh for a battery that should have 4170 mAh, the wear is more than 15%. This is a significant loss that is noticeable in everyday use.
Remember that physical wear and tear is irreversible. Chemical reactions inside the battery slow down over time, and internal resistance increases. No amount of “calibration” will return lost milliamp-hours; they will only help the controller more accurately display the remaining percentage of charge.
Interpretation of results and signs of wear
Having received a capacity figure, many users do not know what to do with it. What percentage of wear is considered normal, and when is it time to go to a service center? Lithium-ion batteries are designed on average for 500-800 full charge cycles before losing 20% of capacity.
If your smartphone shows a residual capacity of 80-85% of the factory one, this is a normal indicator for a device 1.5-2 years old with active use. A decrease to 70% and below is usually accompanied by a noticeable reduction in battery life and possible sudden shutdowns in the cold or under load.
⚠️ Attention: If the phone turns off at 15-20% charge or the charge percentage “jumps” (for example, from 40% immediately to 10%), this is a sign of deep degradation of the cell or a faulty controller, even if applications show normal capacity.
You should also pay attention to the charging speed. Old batteries often cannot accept the high current of fast charging Super Fast Chargingwhich is why the process of filling the battery takes much longer than before. This is the controller's safety mechanism to prevent the worn-out cell from overheating and catching fire.
In conclusion, regularly monitoring the battery health helps plan replacement before the smartphone becomes unusable. Combine data from applications, the service menu and your own observations of the device’s operating time to get a complete picture.
Is it harmful to check the battery with third-party applications?
No, monitoring applications themselves do not harm the battery. They only read data from sensors. However, the constant running of such apps in the background can slightly increase battery consumption, since they use processor time for calculations.
Is it possible to restore the capacity of an old battery?
It is impossible to physically restore the chemical composition of a worn-out battery. All "calibration" methods only train the controller to correctly display the percentage of charge, but do not add actual milliamp hours. The only way is to replace the element.
Why is Samsung not showing the exact capacity in the settings?
Manufacturers deliberately hide the exact technical parameters to avoid user panic due to natural wear and tear. It is more important for them to report a critical condition requiring replacement than to show a daily drop in capacity by a fraction of a percent.
Does fast charging affect the rate of capacity loss?
Yes, frequent use of powerful power supplies (25W, 45W) generates more heat. Heat is the main enemy of lithium-ion batteries. To maximize the life of the battery, it is better to use slow charging at night.
How often do you need to diagnose the battery?
It is enough to check the condition of the battery once every 3-6 months. More frequent checking does not make sense, since degradation occurs gradually. Unscheduled diagnostics should be carried out if you notice a sharp decrease in operating time.