The battery is one of the most vulnerable components of a smartphone, and over time, its capacity inevitably decreases. If your Xiaomi starts to run too fast or shut down at 20-30% charge, it's time to check the real state of the battery. But how do you do this correctly without having to disassemble the device?
In this article, we will discuss 5 Proven methods – from built-in tools MIUI You'll learn how to interpret wear indicators, what values are considered critical, and what to do if the capacity falls below. 70%. We will pay special attention to the Redmi Note models. 10/11/12, POCO X3/X4 and flagships Xiaomi 12/13/14, Where diagnostic algorithms may differ.
Important: Battery capacity data in smartphone settings (Settings → Battery) often show a nominal value rather than a real one. For example, if a manufacturer has declared 5,000 mAh, the system can display this figure even if the actual capacity has dropped to 3800 mAh.
1. Check through the engineering menu (#4636##)
The fastest way is to use the hidden engineering menu available on all Xiaomi smartphones running MIUI. This method does not require root rights and works even on blocked downloaders.
Instructions:
- 📱 Open the phone app and enter the combination: ##4636##
- 🔧 In the menu that appears, select Battery Information)
- 📊 Note the lines: Level - current charge level in percentage Health - battery state (Good means wear up to 20%) Capacity - real capacity in mAh (if there is no field, use other methods)
⚠️ Note: On some models (e.g, POCO F3 or Redmi K40) The Capacity field may not be displayed correctly or correctly, in which case move on to the next method.
Try another one. USSD-code (#6484##)
Use the AccuBattery application
Connect to the PC and check through ADB
Reset your network settings (sometimes helps)
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2.AccumBattery application: detailed wear analysis
AccuBattery is one of the most accurate battery monitoring apps that works on all Xiaomi smartphones without root.It not only shows real capacity, but also calculates wear percentage, discharge rate and even predicts the remaining battery life.
How to use:
- Download AccuBattery from Google Play.
- Charge the phone to 100% and plug it into charging for another 1 hour (for calibration).
- Open the app and go to the Health tab. Here you'll see: 🔋 Design capacity (e.g. 4200 mAh instead of the claimed 5000 mAh) 📉 Percentage of wear (if more than 30%, it is time to change the battery) 🔄 Number of charging cycles (norm - up to 500 cycles)
at least 3 days
💡 Useful tip: AccuBattery has Charge alarms. Set the notification up to 80% – this will extend the battery life, as constant charging up to 100% accelerates degradation.
Once a month
Once in 3 months
Only when the problems start.
Never calibrated.-->
3. USSD-battery-diagnostic
In addition to the standard engineering menu, Xiaomi smartphones work specialized USSD-These are especially useful if you have a Redmi or a battery checker. POCO with custom firmware where standard methods may not work.
List of working codes:
| Code. | Appointment | Application |
|---|---|---|
| ##6484## | Battery test | Shows voltage, temperature and condition |
| ##44336## | Information on software and battery | Displays MIUI version and battery data |
| ##284## | Equipment test | Includes battery testing in the Battery Test section |
⚠️ Note: Some models (e.g. Xiaomi 13 Pro or Redmi Note 12 Pro)+) These codes can be blocked by the manufacturer. If nothing happens after you enter the code, try using the app. MTK Engineering Mode (for MediaTek processor devices) or move on to the next method.
What to do if USSD-codes don't work?
4. Check through ADB (for advanced users)
If you want the most accurate data on battery capacity, including factory values and current wear, use Android Debug Bridge (ADB).This method requires connecting a smartphone to a PC, but gives the most detailed information.
Step-by-step:
- Download and install ADB Tools on your computer.
- Turn on USB Debugging on your smartphone: Go to Settings → About Phone and 7 times click on the MIUI Version to activate Developer Mode. Return to Settings → Additional → For Developers and enable USB Debugging.
adb shell
dumpsys battery- Capacity – current charge in %
- Voltage - voltage mV
- Technology: A type of battery (usually Li-ion or LiPo)
- charge_counter — Real capacity in mkAh (divided by 1000, to get a mAh)
🔍 Example of conclusion: if in a row charge_counter: 3800000, This means that the actual capacity of your battery — 3800 mAh (instead of the stated 5000 That's the wear and tear (24%) It has a significant impact on autonomy.
💡
ADB is absolutely accurate because it reads information directly from the battery controller, and it’s the only method that works even on smartphones with damaged firmware or a locked bootloader.
5. Comparison with battery wear table
Once you have the actual capacity data, compare it to the factory values and estimate the wear and tear. Below is a table that will help determine whether to change the battery.
| Percentage of wear and tear | Real capacity (from nominal) | Symptoms | Recommendations |
|---|---|---|---|
| 0–10% | 90–100% | No noticeable problems. | Keep using. |
| 10–20% | 80–90% | Moderate reduction of autonomy | Calibration of the battery every 3 months |
| 20–30% | 70–80% | Fast discharge, overheating when charging | Limit the charge to 80%, avoid overheating |
| 30–50% | 50–70% | A sharp drop in charge, spontaneous shutdowns | Battery replacement is recommended |
| >50% | <50% | Phone does not hold charge, battery bloating | Immediate replacement! smartphone damage risk |
💬 Example from practice: If you have Xiaomi Redmi Note 10 Pro with a factory capacity of 5020 mAh, and the real capacity of AccuBattery is 3700 mAh, wear is ~This means that the battery has lost a quarter of its capacity and should be replaced in the next 6 months.
⚠️ Warning: If the actual battery capacity has dropped below 60% of its face value and the smartphone has started to swell (visible by the raised back cover or screen film), immediately stop using it.
6. Alternative methods: applications and service centers
If none of the above methods worked, try the following options:
- 🔧 Annex CPU-Z: It shows the voltage and temperature of the battery, but not the capacity.
- 📱 Mi Service Center: Xiaomi’s official app for checking device status (not available in all regions).
- 🏠 Service center: if you want 100% accurate measurement, contact the authorized Xiaomi service. C7400), which show a container with an error of no more than 1%.
- 🔄 Battery replacement: If wear exceeds 30%, consider replacing.Original batteries for Xiaomi cost between 1500 and 3500 rubles (depending on model).
💡 When replacing a battery, choose only original batteries or certified analogues (for example, from the same battery). ZMI Cheap, unoriginal batteries often have understated capacity and can damage the power controller.
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If you decide to replace the battery yourself, be sure to use a plastic mediator to separate the adhesive layer. Metal tools can puncture the battery and cause a short circuit!