Xiaomi Redmi Note 5 battery calibration: a complete guide with proven methods

The charge indicator on your Xiaomi Redmi Note 5 shows 20% and the smartphone suddenly turns off? Or after charging to 100%, the battery runs out in an hour? These symptoms signal desynchronization of the BMS controller (Battery Management System) and the real state of the battery. Battery calibration is the process of matching the controller data with the actual capacity of the battery.

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3 working methods

Many people mistakenly believe that calibration will return the battery to its original capacity, but it only solves software inaccuracies of the charge display, if the battery is physically worn out (more than 500 charge cycles), you will need to replace it, and before starting the procedure, check the battery status through an engineering menu or an application like AccuBattery.

Signs Redmi Note 5 battery needs calibration

The BMS controller on the Redmi Note 5 may fail due to deep discharges, charging interruptions, or the use of non-original adapters.

• 🔋 The smartphone is turned off when 15-30% The indicator shows the remaining energy.
• 🔄 After connecting the charging percentage immediately jumps from 1% before 20-40%.
• ⚡ Battery's charging to 100% post 10-15 minutes (false operation of the controller).
• 📉 Monitoring applications (e.g, CPU-Z) Disparity with the system indicator by more than 10%.
• 🔌 The phone does not turn on after full discharge, although charging is connected.

If you see at least 2-3 signs from the list, proceed to calibrate. Except that if the battery is swelled or deformed, the procedure is useless, you need to replace the battery.

⚠️ Attention: Don't confuse calibration with battery training (discharge-charge cycle). On modern Xiaomi smartphones, no training is required - this is a myth from the era of nickel-metal hydride batteries. Calibration is only needed to reset the controller data. BMS.

Calibration Preparation: What to Do in Advance

Incorrect preparation can damage the power controller or make problems worse.

Charging up to 100% with the original adapter (5V/2A)

Disabling all background applications

In-plane mode activation

Check the battery temperature (must be 20-35°C)

Creating a backup copy of data (in case of reset)

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Use only the original cable and adapter from Xiaomi. Non-original chargers can deliver unstable voltage, which will distort the calibration results. If you do not have a native adapter, take a certified Quick Charge 3.0 (for example, from Anker or Baseus).

Battery temperature is critical: at values below 15°C or above 40°C, the BMS controller blocks the recording of data. Check the temperature through the engineering menu:

#4636## → "Battery information"

Or install the AIDA64 application (Battery section).

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If the battery temperature is above 40°C, let the smartphone cool off for 15-20 minutes. Do not use cooling stands - a sharp temperature drop is harmful to lithium polymer cells.

Method 1: Calibration without ROOT (via engineering menu)

This is a good way for 90 percent of Redmi Note 5 users, because it doesn't require super-user rights, and we're going to reset the controller data through the hidden MIUI menu.

Steps:

1. Charge your phone to 100% and hold it for another 1 hour (to stabilize the voltage).
2. Turn off the charging and go to the engineering menu: ##36446337####
3. Choose Battery Information → Battery Calibration.
4. Press Calibrate and confirm the action.
5. Discharge your phone until it is automatically turned off (don’t manually turn it off!).
6. Charge up to 100% without interruptions (use the original adapter).

After the cycle is complete, the BMS controller will overwrite the capacitance data, and the effect is noticeable after 1-2 charging cycles.

⚠️ Attention: If the phone starts to run out faster after calibration, it means the battery is physically worn out. In this case, the calibration will only accelerate the degradation - consider replacing the battery.

Method 2: Calibration through ADB (for advanced users)

If the engineering menu is not available, use Android Debug Bridge (ADB).This method requires a computer and basic command line knowledge.

Instructions:

1. Enable USB Debugging in the Developer Settings → About Phone → MIUI Version – Press 7 times, then go back to Additional Settings → For Developers.
2. Connect your phone to your PC and open the command line (Windows) or terminal (macOS/Linux).
3. Enter the commands in order: adb shell su dumpsys battery set ac 1 dumpsys battery reset (If there is no ROOT, skip the su command).
4. Turn off the cable and discharge the phone before it turns off.
5. Charge to 100% without interruption.

The dumpsys battery reset command resets the battery's data cache, and the set ac 1 emulates the network connection, a method that is more efficient than standard, but requires caution.

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The ADB method is the most versatile, but if you don't have any command line experience, use the engineering menu. TWRP reset gives you the best result, but requires unlocking the bootloader and installing a custom Recovery.

Method 3: Completely reset the controller BMS (for ROOT-user-user)

If the two previous methods didn't work, and the battery is still behaving unpredictably, you'll need to reset the BMS deep through the controller files, a method that's risky, because if you make a mistake, the phone might stop turning on.

Step-by-step:

1. Install. TWRP Recovery and you'll get it. ROOT-rights (e.g. through Magisk).
2. Download the file. battery_stats.bin (can be found on the forums 4PDA or XDA).
3. Reboot to TWRP and connect your phone to your PC.
4. In the terminal, perform: adb pull /data/system/battery_stats.bin adb shell su rm /data/system/battery_stats.bin reboot
5. After rebooting, discharge the phone to 0% and charge to 100% without interruptions.

This method completely erases the charging history, forcing the controller to retrain from scratch, only use it if other methods have not worked.

⚠️ Attention: Removal battery_stats.bin firmware MIUI If the phone starts to overheat after the procedure, reset to factory settings.

How to check the calibration result

To make sure that the calibration is successful, use these tools:

• 📊 AccuBattery shows the actual capacity and wear of the battery, and after calibration, the difference between Design Capacity and Estimated Capacity should be reduced.
• 🔧 AIDA64 — Check the battery voltage in the Battery section. 100% It should be a charge. 4.35-4.40V.
• 📈 MIUI Battery Care — track the discharge schedule. Once calibrated, it should be smooth, without jumping.
• 🔄 Cycle test: Discharge your phone to 15%, then charge to 80% and check if the percentage matches real-life life.

If the problems returned after 2-3 days, it means:

1. The battery is physically worn out (replacement is required).
2. The BMS controller is damaged (motherboard repair is required).
3. The MIUI firmware contains bugs (try updating or reflashing your phone).

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For accurate wear diagnosis, use the Battery Guru app. It shows the number of charging cycles and current capacity in mAh. If the value is below 2500 mAh (at the initial 4000 mAh), the battery must be replaced.

Frequent Mistakes and How to Avoid Them

Many users are making battery problems worse by doing things wrong, and this is what you can't do when calibrating the Redmi Note 5:

• ❌ Interrupt the charging/discharge cycle (this knocks the controller down even more).
• ❌ Use "fast charging" during calibration (stable current required) 5V/2A).
• ❌ Calibrate the battery at a temperature below 10°C or higher than 45°C.
• ❌ Install applications to “battery optimization” (they only interfere with the system) BMS).
• ❌ Reset your phone settings to factory without backup.

Also avoid these myths:

❌ "We need to unload the phone before 0% every month is bad for lithium polymer batteries: 20-80%. ❌ "Calibration restores capacity – no, it only corrects the controller data. ❌ "You can calibrate it with apps like Battery Calibration — these programs are useless without them. ROOT.

If after calibration the phone began to discharge faster, check:

1. Background processes (use Greenify to stop them)
2. Battery condition (swelling, deformation).
3. Energy saving settings (Settings → Battery → Energy saving mode).

FAQ: Answers to popular questions