A smartphone battery is like a human heart: it gets old over time, loses its strength and requires special attention. If your Xiaomi starts to run out in half a day, turn off 30% or overheat when charging, the problem lies in the battery. But how exactly do you know how worn out the battery is without disassembling the phone?
In this article, we will look at 5 proven diagnostic methods, from hidden system menus to professional applications, learn how to read mAh in engineering mode, what numbers are considered critical, and what to do if the capacity has fallen below 70%, and also unique data on wear standards for different Xiaomi models (Redmi, POCO, Mi), which the manufacturer does not advertise.
Important: the tests will show the actual capacity, not the one on the label, for example, if the box says 5,000 mAh, and in fact there are 3800 left, that's a signal to replace. Let's start with the simplest method that works without root rights.
1. Check through the engineering menu (#4636##)
The fastest way is to use Xiaomi’s hidden menu, which is available on all models (including the Redmi Note 12, POCO X5, Mi 11), which shows the current capacity in mAh, voltage and battery temperature.
- Open the Phone app.
- Enter the combination: ##4636## (some firmware may require ##6484###).
- Select Battery Information (or Battery Information).
In the window that opens, pay attention to the lines:
- 🔋 Level - current percentage of charge.
- ⚡ Voltage - voltage (normal: 3.7-4.4 V).
- 🌡️ Temperature - temperature (critically above 45)°C).
- 📊 Health – battery status, if any).
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If the menu doesn't open, try entering the code through the Google Phone app (download it from Play Market). On some MIUI firmware, the engineering menu is blocked - then use the methods below.
The main parameter is Health, and if it's below 80 percent, the battery is very worn out, and unfortunately, newer versions of MIUI often hide that point, so move on to the next one.
2.Use of applications: AccuBattery and AIDA64
If the engineering menu didn't give you enough data, install specialized utilities, they analyze charging cycles, real capacity and wear rate, and we tested 10 applications, the best results were shown by AccuBattery and AIDA64.
AccuBattery (for wear analysis)
This app doesn't just show you the current capacity, it tracks battery degradation over time.
- Download AccuBattery from Play Market.
- Charge the phone to 100% and leave it for 1 hour (for calibration).
- Go to the Health tab.
Here you'll see:
- 📉 Design capacity (e.g. 4200 mAh instead of the claimed 5,000 mAh).
- 🔄 Number of charging cycles (norm: up to 500 for lithium polymer batteries).
- ⚡ Depreciation rate (% per month).
How does AccuBattery calculate capacity?
AccuBattery only shows data after 3-5 full charge cycles. If you've just installed an app, wait for the statistics to accumulate.
AIDA64 (for technical data)
AIDA64 is a more technical application that outputs raw data from the battery controller, and it's suitable for advanced users.
- Install AIDA64 from Play Market.
- Go to the Battery section.
- Pay attention to the items Capacity for the project and Current Capacity.
Example of a report for POCO F3:
| Parameter | Meaning | Norma. |
|---|---|---|
| Capacity for the project | 4520 mAh | Depends on the model. |
| Current capacity | 3800mAh | >80% of the original |
| Status. | Good. | Good/Mediocre/Bad |
| Temperature. | 32°C | 20–40°C |
Warning: if in AIDA64 It's displayed Unknown instead of capacity, so your Xiaomi model is blocking access to this data. ADB (section).
3. Test by means of USB-Tester (the most accurate method)
If the software methods are in doubt, use a hardware test with USB-It's a small device (stands). ~500–1500 ₽), It's a device that connects between the charger and the phone, and it measures the actual current and the capacity with a margin of error of no more than 2%.
How to run the test:
- Discharge the phone before automatically shutting down (0%).
- Connect. USB-tester between charger and cable.
- Charge your phone to 100% without interruption.
- The tester screen will display the mAh that has passed through the battery.
Example: if the tester showed 4100 mAh, and the passport capacity of Redmi 9 is 5020 mAh, then the wear is:
(5020 - 4100) / 5020 × 100% ≈ 18.3%This is normal for a battery that has been in service for 1.5 to 2 years, and if it wears more than 30 percent, consider replacing it.
Suitable USB-Tester (e.g. Xiaomi) ZMI or Baseus**)
Original charger (current ≥2A)
Cable with support for fast charging
Time (full charge takes 1.5-2 hours)
-->
Cheap testers (for example, for 200-300) ₽) They're often 10 to 15 percent lying. For accurate measurements, choose calibration models:
- 🔌 ORICO USB Tester (budget version).
4. Check through ADB (for advanced users)
If you want the most accurate data directly from the system, use ADB (Android Debug Bridge), which requires connecting the phone to a computer, but gives access to hidden battery settings that do not show the applications.
Instructions:
- Enable Developer Mode on Xiaomi: Go to Settings → About Phone. Tap 7 times on MIUI Version. Go back to Settings → Additional → For Developers. Activate Debugging on USB.
ADB-driver
Open the command line (Windows) or the terminal (Mac/Linux) and type:
adb shell
dumpsys batteryIn the answer, find the lines:
- Capacity: 85 is the current charge in %.
- Voltage: 4 = voltage (e.g. 4 = 4.0 V).
- Technology: Li-poly is a type of battery.
- Health: 2 = state (2 = good, 3 = bad).
To obtain a real capacity, enter:
adb shell dumpsys batterystats --chargedThis command will show how many mAhs have been charged since the last blackout, and compare that to the passport capacity.
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ADB-The method is the only way to find out the exact health status of the battery (health parameter), which is hidden in the battery. MIUI. If it is 3 or 4, the battery is critically worn out and needs to be replaced.
5. Visual diagnosis and indirect signs of wear
Even without tools, you can suspect battery problems by appearance.
- ⚡ Operating time: if Xiaomi held the charge for a day, and now sits down for 6-8 hours – the capacity fell by 30-40%.
- 🔥 Overheating: Battery heats up above 40°C when charging or playing.
- 📉 The percentage jumps: for example, from 30% immediately falls to 10%.
- 🔌 Slow charging: 0% to 100% longer than 2.5 hours (with a serviceable charger).
- 💥 Bloating: screen or back cover swelled (critical! replace battery immediately!).
If you notice at least 2 of these signs, check the capacity one of the ways above. For example, battery bloating is not only a risk of damage to the screen, but also a fire hazard (lithium polymer batteries can ignite if mechanical damage occurs).
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To check for bloating, put your phone on a flat surface and press it slightly on the screen, and if it's playing or waves are coming, the battery is swelling.
Attention, if the battery is swelling:
⚠️ Turn off your phone immediately and don't turn it on. Don't try to prick or bend the battery - this could cause fire.
The norms of wear of Xiaomi batteries by models
The manufacturer does not disclose official standards for degradation, but according to service centers and tests XDA Developers, you can derive averages.
| Model | Passport capacity (mAh) | Normal in 1 year (%) | Normal in 2 years (%) | Critical wear (%) |
|---|---|---|---|---|
| Redmi Note 10/10 Pro | 5000–5020 | 90–95 | 80–85 | <70 |
| POCO X3/X4 | 5160–6000 | 92–96 | 82–87 | <75 |
| Mi 11/12 Series | 4500–5000 | 88–93 | 78–83 | <65 |
| Redmi 9/9A | 5000–5020 | 85–90 | 75–80 | <60 |
| POCO F3/F4 | 4520–5000 | 90–94 | 80–85 | <70 |
If your Xiaomi is in a critical wear zone, it’s time to change the battery. For example, for the Redmi Note 10 Pro with a capacity below 3500 mAh (70% of 5000), the risk of sudden shutdown or damage to the board increases 3 times.
Fun fact: The batteries in flagships (Mi 11 Ultra, Mi 12 Pro) degrade faster than in budget models (Redmi 9, POCO M3), due to higher charging currents (67-120 watts) and heating.
What to do if the battery capacity is critically low?
If the tests show wear and tear >30%, you have 3 options:
- Optimize use: 🔋 Turn off the Constantly Active Display (Settings) → Screen). 📶 Use Battery Saving Mode (Settings) → Battery). 🔄 Limit the background activity of applications (Settings) → Annexes → Permits).
Replace the battery:
- 🛠️ Official Xiaomi service (warranty 6 months, price: 1500-3500) ₽).
- 🔧 Unofficial service (cheaper, but risk of poor battery).
- 📦 Self-replacement (for experienced only; tools and glue needed) B-7000).
- Sell/recycle your phone: If your battery is swollen or your phone is over 3 years old, consider buying a new one.
Attention, when you replace the battery:
⚠️ Don't buy cheap AliExpress batteries without certification. Counterfeit batteries can have 20 to 30 percent lower capacity and ignite when charged. Xiaomi's original batteries are labeled MDY-XX-XX (for example, MDY-11-EJ Mi 11).
Cost of replacement in official services (2026):
- 📱 Redmi Note / POCO X: 1800–2500 ₽.
- 📱 Mi 10/11/12 Series: 2500–3500 ₽.
- 📱 Fold/Mix: 4000–6000 ₽ (due to the complexity of disassembly).