How to know the battery capacity on Xiaomi: from factory data to hidden commands

Have you noticed that Xiaomi’s smartphone is running out too quickly, even though it used to last longer? Or do you want to check if you’ve “swapped” your battery when you’re repairing it? Battery capacity is a key parameter that directly affects the battery life of your device. Unfortunately, manufacturers often give you a rated capacity (e.g., 5,000 mAh), but over time, the actual volume decreases due to the degradation of lithium-ion cells.

In this article, we will explore all the available ways to test battery capacity on Xiaomi, Redmi and POCO smartphones, from standard MIUI tools to engineering teams and third-party utilities. You will learn how to distinguish real capacity from the declared by the manufacturer, why data may diverge, and what to do if the battery “sank” by 30% or more. Instructions are relevant for models 2018-2026, including flagships (Xiaomi 14, 13T Pro) and budget series (Redmi Note 12, POCO X5).

1. Verification through standard MIUI settings

The easiest way is to use the built-in MIUI tools, which will not show the exact capacity in milliamp-hours (mAh), but will give an idea of the state of the battery through the wear index.

Instructions:

• 📱 Open the Settings app → Battery and productivity.
• 🔋 Go to Battery Status (on some models – Battery Health).
• 📊 This will show the percentage of wear (for example, 85% means that the capacity has decreased by 15%).

⚠️ Note: Xiaomi smartphones older than 2020 may not have this section, in which case use alternative methods from the following sections.

Engineering menu: hidden codes for diagnostics

With service codes, you can get detailed information about the battery, including real capacity, voltage and temperature, which works on most Xiaomi devices, but you need to be careful not to change the parameters in the engineering menu!

Steps:

1. Open the phone app and enter the combination: ##4636##
2. In the menu that opens, select Battery Information.
3. Pay attention to the fields: 🔋 Level - current charge in percentage. ⚡ Voltage - voltage (normal: 3.7-4.4 V). 📏 Capacity - real capacity in mAh (may be absent on new models).

⚠️ Note: If the Capacity field shows a value 0 or N/A, It doesn't mean that the battery is dead, but it's likely that your model doesn't support output of that parameter through code.

3. Diagnostic applications: AccuBattery, CPU-Z and others

The utility side allows you to track battery degradation, real capacity, and even predict the remaining lifespan, and we tested 5 popular applications -- the results in the table below.

Recommendation: For most users, AccuBattery or CPU-Z is sufficient. If you need the most accurate data (for example, for diagnostics before replacing the battery), use the 3C Battery Monitor with ROOT rights.

4. ADB-Teams: for advanced users

If standard methods don’t work, you can get battery data through Android Debug Bridge (ADB), which requires connecting your smartphone to your PC, but provides the most complete information, including actual capacity, battery manufacturing technology, and the number of charging cycles.

Instructions:

1. Install. ADB-PC drivers.
2. Turn on USB Debugging on your smartphone: Settings → About Phone → MIUI Version (click 7 times to activate Developer Mode) → Additional settings → For Developers → Debugging over USB.
3. Connect your phone to your PC and execute the command line: adb shell dumpsys battery
4. Find the lines: capacity - current charge in %. voltage - voltage. charge counter - real capacity in μA·h (divide by 1000 to get mA·h).

💡 Example of conclusion: If the charge counter field indicates 3.5 million, the actual capacity of your battery is 3500 mAh (at a nominal value of 5000 mAh this means wear by 30 mAh%).

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If ADB Does not recognize the device, try reinstalling the drivers or using an alternative command: adb shell cat /sys/class/power_supply/battery/capacity.

5. Physical check: what is written on the battery

If you have access to an internal battery (such as when you replace it), you can find out its rated capacity directly, a method that is suitable for devices with a removable battery (a rarity in modern Xiaomi) or when disassembling a smartphone.

Where to look for information:

• 📄 Battery sticker: usually the capacity is indicated (for example, 4500mAh), tension (3.85V) model.
• 🔍 Serial number: it can be found specifications in the manufacturer's database.
• 🛠️ Contact marking: some batteries are applied QR-technical code.

⚠️ Note: Disassembly of the Xiaomi smartphone without experience can lead to damage to the plumes or loss of tightness (relevant for models with protection) IP53/IP68, for example, Xiaomi 13 Ultra or Redmi Note 12 Pro+). If you are not sure, contact the service center.

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Even if the battery has a capacity of 5,000 mAh, the real one can vary by 10 to 15 percent because of manufacturing standards, and manufacturers often round things up.

Comparison with passport data: why the numbers do not match

You checked the container and you found that the actual value was lower than the stated value?

• 🔋 Degradation: Lithium-ion batteries are losing ~20% capacity after 500 charging cycles.
• 📉 Marketing: Manufacturers specify a typical capacity (for example, 5000 mAh), but the real one can be 4800-4,900 mAh.
• 🌡️ Temperature: Overheating (>40°C) or refrigeration (<0°C) capacity is temporarily reduced.
• ⚡ Fast Charging: Using the Turbo Charge (33W/67W/120W) accelerates the degradation of 10–15% yearly.

📊 Xiaomi Battery Degradation Table by Year (Average Values):

7.When it's time to change the battery: signs of critical wear

If the battery capacity has dropped below 60-70% of its value, it's critical.

• ⚡ Smartphone discharges by 30-50% in 1-2 hours without load.
• 🔥 Overheating when charging or using (above 45)°C).
• 📉 Sudden shutdowns at 20–30% charge.
• 🔌 Slow charging (e.g., slow charging, 33W charger 10W).
• 💥 Bloating of the body (seen from the raised screen or back cover).

⚠️ Warning: If the battery is swollen, immediately turn off the smartphone and do not use it until the battery is replaced.

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Xiaomi’s original batteries cost 30-50% more than their counterparts, but last 2-3 times longer.

FAQ: Frequent questions about Xiaomi's battery capacity