The battery is one of the most vulnerable components of a smartphone, and over time, its capacity inevitably decreases. If your Xiaomi, Redmi or POCO has become more quickly discharged, overheated or suddenly shut down, it’s time to check the status of the battery. In this article, we will analyze all the available methods of diagnosing batteries, from standard MIUI tools to hidden engineering menus and third-party applications.
It’s important to understand that even new smartphones can have battery problems due to factory defects, misuse or use of unoriginal chargers, and we’ll show you how to accurately determine the actual wear of the battery without disassembling the phone, and we’ll give you recommendations on what to do if the capacity falls below a critical level.
1. Checking the status of the battery through the standard settings MIUI
The easiest way to assess battery health is to use the built-in MIUI tools, which are available on all modern Xiaomi models, starting with MIUI 12 and later.
Open Settings → Battery and Performance → Battery status. Here you will see two key parameters: Current capacity (in mAh) and Degree of wear (in percent). For example, if the original capacity was 5000 mAh and the current capacity was 4200 mAh, wear will be 16%.
- 🔋 Green indicator (0-10% wear) – battery in excellent condition.
- 🟡 Yellow indicator (10–30%) – a noticeable decrease in capacity, it is worth thinking about replacing.
- 🔴 Red indicator (30%+) — critical wear, the replacement of the battery is required.
Note: on some models (such as the Xiaomi 11T or Redmi Note 10 Pro), this section may be called Battery State or Battery Health. If you don't see it on the menu, upgrade MIUI to the latest version.
⚠️ Attention: Built-in diagnostics MIUI It may show inaccurate data on custom firmware phones or after resetting to factory settings. In such cases, use alternative methods (see sections below).
2. Hidden engineering codes for the diagnosis of battery
For more detailed checks, you can use service codes that open access to hidden test menus, which work on most Xiaomi devices, but may vary depending on the model and version of MIUI.
Enter the following combinations in the Phone app: ##4636## → Select Battery Information.
- 📊 Charge level (B %)
- 🔌 Voltage (in mV, normal: 3700-4200 mV)
- 🌡️ Temperature (optimum: 25–40)°C)
- 🔄 Technology (e.g. Li-polymer)
Another useful code is ##6484## → MBT Info (on some models) which shows the actual battery capacity in mAh, which is comparable to passport data. For example, if your Redmi Note 12 Pro+ is supposed to have 5,000 mAh, and here it says 4300 mAh, the wear is 14%.
| Parameter | Normal value. | Critical significance |
|---|---|---|
| Voltage (mV) | 3700–4200 | <3500 or >4300 |
| Temperature (°C) | 25–40 | >50 or <0 |
| Capacity (mAh) | 80-100% of the passport | <60% |
| Charging cycles | <500 | >800 |
⚠️ Note: If you enter the code and you see a message saying "No connection to the server", your Xiaomi model does not support this method. Try alternative methods or check the codes for a particular line (for example, for a specific line). POCO It can work #663368378##).
3. Applications for deep battery diagnostics
If the built-in MIUI tools seem inadequate, third-party utilities can be installed, providing more detailed information, including discharge schedules, charging cycle history, and lifetime forecast.
Top.-3 Proven applications for Xiaomi:
- 📱 AccuBattery shows real capacity, discharge rate and wear. There's a battery calibration function.
- 🔍 CPU-Z — Battery displays voltage, temperature and battery technology.
- 🛠️ AIDA64 — Provides the most detailed information, including the number of charging cycles and passport details.
Example of working with AccuBattery:
1. Install the app from Google Play.
2. Charge the phone to 100% and turn off charging.
3. Use your smartphone as usual until the charge drops to 20%.
4. In Health section you will see the actual battery capacity and the percentage of wear and tear.
☑️ Preparation for battery test
Tip: For the most accurate results, do the test for 2-3 days, avoid using the phone in extreme temperatures (for example, in the cold or in direct sunlight), as this distorts the readings.
4. Check through ADB (for advanced users)
If you want the most accurate data on the battery, you can use ADB (Android Debug Bridge), which requires connecting the phone to a computer, but gives you access to hidden parameters that standard tools don't show.
Instructions:
1. Enable USB Debugging in the Developer Settings (Settings → About Phone → MIUI Version – Press 7 times, then return to Additional → For Developers).
2. Connect your phone to your PC and open the command prompt (or Terminal on Mac/Linux).
3. Enter the command:
adb shell dumpsys batteryYou'll get data like this:
level: 85
voltage: 3987
temperature: 320 (32.0°C)
capacity: 4500Decoding of key parameters:
- Level is the current charge in %.
- Voltage is voltage in mV (normal: 3700-4200).
- temperature - temperature in tenths of °C (320 = 32.0 °C).
- Capacity - current capacity in mAh (compare with passport).
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If the dumpsy battery command is not working, try the adb shell cat. /sys/class/power_supply/battery/uevent — It will display similar data in a different format.
5. Physical Diagnosis: When to Open Your Phone
If software methods show critical problems but you doubt their accuracy, you can do a visual inspection of the battery, which is true for phones older than 2-3 years or after falling/watering.
Signs of a faulty battery:
- 🔥 Bloating – the phone body is deformed, the screen “steps away” from the frame.
- 💧 Contact oxidation – green or white coating on the battery connector.
- 🔌 Traces of overheating - blackened areas on the battery or motherboard.
How to safely remove the battery:
1. Turn off the phone and remove the SIM- card.
2. Use a plastic shoulder blade or mediator to gently plug the back cover (on models with a non-removable battery, such as the Xiaomi 13, you will need to heat up the adhesive with a hairdryer).
3. disconnect the battery plume from the motherboard (don't pull the wires!).
4. Examine the battery for bloating or damage.
⚠️ Attention: A bloated battery can explode if punctured or pressed hard. If you notice a deformity, take the phone to a service center immediately!
What to do if the battery is blown?
6.How to extend the life of the Xiaomi battery: 7 rules
Even if your battery is still in good condition, following simple rules can slow its wear and wear and extend its lifespan by 20 to 30 percent.
- 🔌 Avoid full discharge – charge your phone at 20-30% charge, without bringing it to 0%.
- ⚡ Don’t keep charging all night – turn off the cable after 100% (or use smart charging in settings) MIUI).
- 🌡️ Watch the temperature – do not play heavy games while charging and do not leave your phone in the sun.
- 🔄 Use original chargers – cheap cables and power supplies accelerate the degradation of batteries.
- 📵 Disable unnecessary functions — GPS, Bluetooth and 5G in the background, the battery is severely discharged.
- 🔋 Calibrate the battery once every 3 months – discharge the phone to 0%, then charge to 100% without interruptions.
- 🛠️ Update. MIUI — In new versions of the firmware optimized energy consumption.
On Xiaomi models with fast charging support (such as the Xiaomi 12 Pro or POCO F4 GT), try not to use turbo mode all the time. Better to charge in the standard way (18W) - this reduces heat and wear.
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The optimal charge level for battery life is 30-80%, and constant charging up to 100% reduces battery life by 15-20% per year.
7 When it's time to change the battery: signs and cost
If the diagnosis showed wear and tear of more than 30%, or you observe the following symptoms, it is time to think about replacing the battery:
- ⚡ The phone will run out in 2-3 hours with normal use.
- 🔌 Charging jumps (for example, from 50% immediately to 20%).
- 🔥 The body is very hot even without loading.
- 📉 In applications like AccuBattery, capacity fell below 60% of passport capacity.
The cost of replacing the battery in official Xiaomi services (for 2026):
| Model | Cost (₽) | Time to change |
|---|---|---|
| Redmi Note 10/11 | 1 800–2 500 | 1-2 hours |
| Xiaomi 12/13 | 2 500–3 500 | 2-3 hours |
| POCO X3/X4 | 2 000–2 800 | 1 hour |
| Xiaomi Mi 11 Ultra | 3 500–4 500 | 3 hours |
Important: In informal services, replacement may cost less (20–40%), but there is a risk of installing a poor-quality battery. The original Xiaomi batteries are marked MDY-XX (where XX is the model code) and a hologram on the package.