How to find out the level of wear of the battery on the smartphone Xiaomi

Xiaomi’s current smartphones, which run MIUI or HyperOS shells, have powerful iron and capacious batteries, but over time, even the best lithium polymer cells lose their original capacity. Owners often notice that a device that used to run for two days without recharging now runs out by evening or suddenly shuts down at 15% charge.

Determining the exact percentage of battery health on Android is more difficult than on iOS, where it is built into the default system. However, in the Xiaomi ecosystem there are several hidden tools, engineering menus and third-party utilities that allow you to get comprehensive information about the status of the Li-Po battery. We will look at all the methods available, from simple codes to professional diagnostics via the computer.

Understanding the current state of your battery is critical not only for battery life, but also for device safety. A severely worn battery can swell, damaging the screen or motherboard, or causing a power controller to malfunction, so regularly checking the capacity should be a useful habit for any user who wants to extend the life of their gadget.

Symptoms of battery degradation and when to check

Before we get to the technical diagnostics, we should look at the indirect signs that the smartphone itself gives. Android can analyze the behavior of voltage, but it does not always display this data in a prominent place. If your Xiaomi has begun to behave strangely, this may be the first bell.

One of the most obvious symptoms is a sharp drop in battery percentage, such as a phone showing 40%, and after 5 minutes a sudden drop to 10% or an instant shutdown, which indicates that voltage under load drops below critical levels, which is typical of old battery cells, and you should also be alert if the device is very warm even for simple tasks like watching social networks.

• 🔋 The smartphone is turned off when the remaining charge is more than 20%.
• 🌡️ The device is significantly heated in the area of the camera or screen during charging.
• ⏳ The working time has been reduced by half compared to the period after the purchase.
• 🔌 Charging occurs unevenly: quickly dialed up to 80% and very long stays on 100%.

It's important to understand that software failures can mimic wear, and sometimes calibration or resetting helps, but if the physical wear of the chemistry is too great, software won't fix it, and if you see at least two of the signs in the list above, you need to do a deep diagnostic.

Using the CIT Engineering Menu for Diagnostics

The most reliable way to access hidden hardware settings on Xiaomi smartphones is through the CIT (Customer Inspection Test) engineering menu, a tool created by plant engineers to test devices before sale and contains data that is not displayed in the normal interface.

You don't have to be a programmer to log in to the menu. You just have to open a standard caller and type a special code. On most Xiaomi models, this is a combination of ##6485##. Once you enter the code, the phone will automatically open a window with technical information. If the code doesn't work, try #4636#, although it is more commonly used to set up networks, but may contain battery data.

The list that opens will include the lines that contain information about battery health. The interface may vary depending on the version of MIUI, but the key parameters are usually standard notations:

• 📊 MB_06: The battery health status (Good, Bad, Overheat).
• 📉 MB_00: Current percentage of battery charge.
• 🏭 MF_02: Number of full charge cycles (Cycle Count).
• 🔋 MF_05: Actual capacity (residual capacity in mAh).

⚠️ Warning: Do not change the values in the engineering menu unless you know exactly what they are responsible for. Some parameters may recalibrate the power controller, which will lead to incorrect display of the charge.

If in a line MB_06 "Good" means that the controller does not see critical errors. 100% A more accurate picture is the current capacity compared to the factory capacity. For new firmware versions, some codes may be blocked, so you should pay attention to the built-in Security app".

Analysis through the built-in application "Security"

The MIUI and HyperOS shells have a Security system application that combines antivirus, memory cleanup and optimizer. Few people know, but the latest firmware versions have a battery diagnostic feature that gives a more intuitive score than the dry numbers of the engineering menu.

To use this method, open the Safety app, go to the Battery section or click on the gear icon in the upper right corner, then select Battery Status. The system will run a quick test and give a rating: "Normal", "Good" or a recommendation to replace the battery.

This is a good way to be simple, but it's less informative for advanced users. You won't see the exact number of cycles or the current voltage here. But for the average user who wants to quickly figure out whether to worry, that's enough. It analyzes charge history and current performance.

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To get more accurate data in the Safety app, pre-discharge the phone to 0% and charge to 100% without interruption, which will help the system recalibrate the controller.

Third-party applications for accurate diagnosis

If Xiaomi’s built-in tools don’t seem detailed enough, Google Play Store apps can read data directly from the power controller and provide detailed statistics, graphs, and forecasts.

One of the most popular and accurate tools is AccuBattery, which is a data-storage app, where the longer you use a phone with an app installed, the more accurately it determines the actual capacity, and it compares the declared capacity with the actual energy consumed.

Another powerful tool is CPU-Z or Ampere, which shows current voltage, temperature and current in real time, and is useful for identifying faulty chargers or cables that can accelerate battery wear.

Using third-party software has one caveat: applications must be constantly hanging in the background, which is self-consuming, so after diagnosis (usually requires 3-5 full cycles for accuracy), they are better off or removed.

Professional Method: Diagnosis through ADB

For those who want to get the most accurate data without installing unnecessary applications and having superuser rights, the ideal solution is to use the Android Debug Bridge (ADB) debugging bridge, which allows you to read raw data from the system files of the battery.

To start, activate the developer mode on your smartphone. Go to Settings → About Phone and quickly click on the MIUI Version 7 times. Then, in the Advanced Settings menu → For developers, turn on Debugging over USB.

Connect your smartphone to your computer with a cable and open the Command Prompt (CMD) or PowerShell in the folder with the ADB installed. Enter the following command for full battery information:

adb shell dumpsys battery

You will get a list of parameters. We are interested in scale strings (maximum charge, usually 100), level (current level), and most importantly, status. However, to get exactly the capacity (mAh) and cycles through ADB on Xiaomi, you often need to execute a command:

adb shell cat /sys/class/power_supply/battery/capacity

Or a deeper request to the file system:

adb shell cat /sys/class/power_supply/battery/charge_counter

Received value charge_counter It will show the current capacity in mAh, dividing this number by the factory capacity of your model (for example, 5000 mAh) and multiplied by 100, You get a real percentage of the battery's health, and that's the most objective method, because it takes data directly from the core of the system.

⚠️ Attention: Teams ADB Register sensitive letters. Type them exactly as you're told. Error commands may not be executed, but are generally safe for the system if you only use reading (cat/dumpsys).

Factors accelerating the wear of Xiaomi battery

Understanding the causes of degradation will help you extend the life of a new battery or slow down the death of an old one. The lithium polymer batteries Xiaomi uses are sensitive not only to time but also to operating conditions.

The main enemy is heat. Playing heavy games (PUBG, Genshin Impact) while charging is a guaranteed way to kill a battery in a year. Heating above 40-45 degrees Celsius triggers irreversible chemical reactions inside the cell.

Extreme states of charge are also harmful: 100% phone retention (like charging at night without a smart controller) or regular zero discharge create stress for chemistry, the optimal range for a long life is between 20% and 80%.

• 🌡️ Use of non-original power supplies with unstable current.
• 📱 Operation in extreme cold conditions (below) -10°C).
• ⚡ Frequently using fast charging of maximum power without the need.
• 🔋 Long-term storage of the phone in a completely discharged state.

Xiaomi implements protection features such as Optimized Charging, which learn your habits and slow down charging at night to complete it by the time you wake up, and it is recommended not to turn off these features, as they really help save life.

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The fastest way to kill a battery is to heat it above 45 degrees during fast charging.Try not to cover the charging phone with a blanket and remove the thick case.

Frequently Asked Questions (FAQ)