How to Check Battery Capacity on Xiaomi: From Hidden Codes to Professional Tests

The battery is the most vulnerable part of Xiaomi, Redmi and POCO. Even after a year of active use, the actual battery capacity can be reduced by 20-30%, leading to rapid discharge, sudden shutdowns at 15-20% charge and overheating during charging. But how do you know the exact residual capacity without disassembling the device or contacting a service center?

In this article, you will find 5 proven ways, from standard MIUI tools to engineering codes and third-party applications. We will analyze how to interpret mAh, which means wear percentage, and why data from different sources can differ. And you will learn which Xiaomi models are prone to premature battery degradation due to firmware errors (spoiler: this is for smartphones on Qualcomm Snapdragon 7xx 2020-2022).

1. Standard MIUI tools: What the "Battery State" shows

The easiest way is to use the built-in MIUI diagnostics, which is available on all Xiaomi smartphones since the MIUI 12 (2020) firmware version, but here’s a nuance: the system does not display absolute capacity in mAh, but the percentage of wear relative to factory values.

To open the menu:

1. Go to Settings → Battery and Performance.
2. Slap the gear icon (⚙️) top-right.
3. Select the Battery Status.

Here you will see two key parameters:

• 🔋 Current capacity – for example, “4,000 mAh out of 5000 mAh” (meaning that the battery has lost 20% capacity).
• ⚡ Charging cycles – number of full discharges/charges (norm: up to 500 cycles for lithium polymer batteries).
• 📉 The system will tell you if the battery needs to be replaced (threshold - usually) 60-70% from the reference tank).

⚠️ Note: Some models (e.g. Xiaomi) 11T Pro or Redmi Note 10 Pro, the battery status item may not be available, due to Xiaomi's policy of hiding diagnostics on flagships, in which case use alternative methods from the following sections.

Engineering menu: hidden codes for diagnostics (#4636##)

The engineering menu is the heart of Android diagnostics, where hardware data, including the battery, is hidden. USSD-The main advantage of the method is the exact values of voltage, temperature and real capacity without installing third-party applications.

Instructions:

1. Open the Phone app.
2. Enter the code ##4636##
3. In the menu that appears, select Battery Information.

Decoding of key parameters:

Note the Health field: if Unknown is listed, it may mean that the battery controller is not calibrated, which will help with a full discharge/charge cycle (discharge the phone before turning off, then charge to 100% without interruptions).

Close all background applications

Connect the charger (for stable readings)

Record the values of voltage and temperature

Compare with factory parameters (see table below)-->

3. Testing applications: AccuBattery vs AIDA64

The standard MIUI tools and the engineering menu provide basic information, but for deep diagnostics, it's better to use specialized applications. The two leaders in this niche are AccuBattery and AIDA64, which differ in their approach to analysis and data accuracy.

AccuBattery (free, with premium options):

• 📊 Considers real capacity based on charging cycles (required) 2-3 full cycle for accurate data).
• 🔋 Shows wear in % and predicts remaining service life.
• ⚡ Tracks charging and discharging speed (useful for identifying “gluttonous” applications).

AIDA64 (paid but with trial period):

• 🛠️ Provides technical data about the battery controller (model, manufacturer, release date).
• 📈 Builds voltage and temperature graphs in real time.
• 🔍 Shows current capacity in mAh (but may require root on some models).

⚠️ Note: On Xiaomi smartphones with MediaTek processors (e.g. Redmi) 9A, POCO M3) AIDA64 It can show undercapacity because of the limitations of the chipset, so trust AccuBattery or the engineering menu.

Comparison of application accuracy on the example of Xiaomi 12 Pro (factory capacity of 4600 mAh):

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If AccuBattery shows wear and tear of more than 30%, but the phone is working normally, try resetting the statistics in the app settings and calibrate the battery (discharge to 0%, then charge to 100% without interruption).

4. ADB-Teams: Professional Diagnostics without Root

For users who are ready to dive into technical details, ADB (Android Debug Bridge) offers the most accurate way to test capacity, a method that does not require root rights, but requires connecting a smartphone to a PC and installing Google’s Platform Tools.

Step-by-step:

1. Enable USB debugging in the developer settings (Settings → About Phone → MIUI version – tap 7 times, then go back to Additional settings → For Developers).
2. Connect your phone to your PC and open the command line in the adb.exe folder.
3. Enter the command to obtain battery data: adb shell dumpsys battery

In the conclusion, find the lines:

• Level: 85 is the current charge in %.
• Voltage: 4123 - voltage in mV.
• Capacity: 4500 – Real capacity in mAh (if supported by the controller)
• Li-polymer is a type of battery.

On some models (e.g., POCO F3 or Xiaomi Mi 11), the dumpsys battery command does not show capacity.

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

⚠️ Note: If after the entry ADB-When you see the no permissions error, it means that the manufacturer has blocked access to the battery data, so the solution is to temporarily obtain root rights (for example, through Magisk) or use the method with AccuBattery.

Physical inspection: multimeter and external chargers

If software methods are in doubt, you can measure the capacity of the battery physically using a multimeter or USB-This method is suitable for users with technical background and requires caution (risk of battery damage if the connection is not correct!).

Tools required:

• 🔌 USB-tester (e.g. tester, UM25C or VC830L) — It shows current, voltage and calculates capacity.
• 🔋 External charger (optional, for test without phone).
• 🛠️ Multimeter (to measure voltage at battery contacts).

The verification algorithm with USB-tester:

1. Discharge the phone before automatically switching off (0%).
2. Connect. USB-Tester between charger and phone.
3. Charge the phone to 100% by capturing the tester data.
4. USB-The tester will show the real capacity in mAh, which the battery was able to accumulate.

Example: if the factory capacity of Redmi Note 9 Pro is 5020 mAh, and the tester showed 3800 mAh, wear is ~24%.

⚠️ Warning: Do not disassemble the phone for multimeter testing if you do not have experience with electronics! Short circuit of the battery contacts can lead to fire or explosion. USB-tester.

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USB-The tester is the only method that shows absolute capacity without depending on the software constraints of Xiaomi.

6.When to change the battery: criteria and signs of wear

Even if tests show wear and tear of 20-30%, it doesn't always mean that the battery needs to be changed urgently, it all depends on the actual behavior of the smartphone.

• 🔥 The phone overheats when charging or under load (games, video shooting).
• ⚡ Charge drops off 30% before 0% post 5-10 minutes (symptom of the controller's "break).
• 🕒 Standby time reduced to less than 12 hours (when the screen is off).
• 🔌 The phone does not turn on without charging, even if it shows 10-20% charge.
• 📉 Testing apps show wear over 40%.

Cost of battery replacement in Xiaomi service centers (2026):

If you choose to replace the battery yourself, pay attention to the quality of the battery. Cheap analogues (for example, without a protection controller) can:

• 🔥 ignite when charging.
• 📉 Lose capacity quickly (wear and tear) 50% post 3-6 months).
• 🕒 Incorrectly display the percentage of charge.

- A hologram with a serial number.

- The Mi or Redmi logo is on the label.

- QR-code that can be checked on the Xiaomi website (for new models).-->

FAQ: Frequent questions about Xiaomi battery check