How to check the battery status on Xiaomi Redmi Note 7: from hidden codes to professional diagnostics

Xiaomi Redmi Note 7 is one of the most popular smartphones of the brand, but over time, even its capacious battery of 4000 mAh begins to lose capacity. If the phone runs out in a few hours, suddenly turns off at 20-30% charge or overheats during charging, it’s time to check the status of the battery. In this article, you will find 5 working methods of diagnosis, from hidden engineering menus to professional applications with detailed statistics.

It is important to understand that batteries based on lithium-polymer cells (Li-Po) degrade even when properly operated. 300-500 Full charging cycles may decrease capacity 20-30%, through 2-3 year of intensive use - before 50%. We will tell you how to accurately measure wear without resorting to disassembling the phone, and what to do if the battery is already tired».

1. Checking through hidden engineering code ##4636##

The fastest way to get basic battery information is to use the Android service menu, which works on all Xiaomi smartphones, including the Redmi Note 7 (lavender and lavenderin models), without installing third-party apps.

Instructions:

• 📱 Open the application "Phone" (standard dialer).
• 🔢 Enter the combination: ##4636### - the menu will open automatically.
• 🔋 Go to the tab "Battery Information" (Battery Information).
• 📊 Note the parameters: Level - current percentage; Status - should be Charging or Discharging; Temperature - normal 25-40°C; Voltage - optimally 3.7–4.2 V.

⚠️ Attention: This menu does not contain any wear data, only current data, if the voltage is below 3.5 V at 20% charge or the temperature is above 45.°C without load, battery requires diagnosis in service center.

Detailed diagnostics through the AccuBattery application

For accurate wear data, we recommend using the AccuBattery app (available on Google Play), which analyzes charging cycles, real capacity and battery degradation rate, and is suitable for all Redmi Note 7 models, including versions with MIUI 10-14 firmware.

How to use:

1. 📥 Install AccuBattery from the official store.
2. 🔄 Charge the phone before 100% and discharge to 0% (pre-shut) 2-3 Once, it calibrates the sensors.
3. 📊 Open the Health tab and it will appear here: 🔋 Design capacity (e.g, 3200 mAh instead of the original 4000 mAhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh); 📉 Percentage of wear (norm to 15-20% post 2 year-end); 🔄 Number of charging cycles.

💡 Useful tip: In AccuBattery settings, enable the option to "Trace the temperature." If the battery regularly heats above 40°C when charging, this is a sign of degradation of elements or a faulty controller.

Charge the phone before 100%|Disable battery optimization for the application|Do not use your phone during discharge|Repeat the cycle 2-3 once-->

3. Analysis via MIUI Battery Care (built-in utility)

Starting with MIUI 12, Xiaomi added a built-in Battery Care tool that tracks battery status, which is less accurate than AccuBattery, but does not require third-party software installation.

How to turn on:

• ⚙️ Go to Settings. → Battery and productivity → Battery status.
• 🔍 Click on Battery Health (Battery Health).
• 📊 The system will show: 🔋 Current capacity as a percentage of factory; 📅 Date of last calibration; ⚡ Recommendations (e.g., “Charge up to 80% to extend lifespan»).

⚠️ Note: If this menu displays the message “Battery needs to be replaced”, the wear has exceeded the limit. 40-50%. Further operation may result in battery bloating or sudden shutdowns.

4. Check through ADB (for advanced users)

If you want the most accurate data, including factory capacity and current wear in milliamp hours, use ADB (Android Debug Bridge), which requires connecting your phone to your computer.

Step-by-step:

1. 🖥️ Install. ADB Tools on PC.
2. 📱 Put the debugging on. USB on the phone: Settings → The phone. → Version. MIUI (Click 7 times to become a developer) → Settings → Additionally. → For developers → Debugging by USB.
3. 🔌 Connect Redmi Note 7 to your computer and execute: Adb shell dumpsys battery
4. 📋 In the conclusion, find the lines: capacity: X - current charge in %; charge counter: Y - real capacity in mAh; health: Z - state (2). = Good, 3. = bad).

Critical information: If the health parameter is 3 (or DEAD), the battery is in a state of disrepair.

5. Visual examination and physical diagnosis

If the software methods show critical wear, check the battery physically.

• 🔧 Screwdriver. T3 or T4 (for disassembling Redmi Note 7);
• 🧲 Plastic blade (so as not to damage the plumes);
• 🔍 Lupa (to inspect contacts).

Signs of a faulty battery:

• 🔋 Bloating – the phone body “splashes”, the screen or back cover is raised;
• 🔥 Traces of oxidation on contacts (green or white plaque);
• 💥 Deformation - the battery is curved, it shows bulges;
• 🔌 Damaged wires (breaks, meltings).

⚠️ Warning: If the battery is swelling, don't try to puncture or bend it! Lithium polymer batteries can ignite if damaged. Turn off your phone immediately and contact the service center.

💡

Before disassembling the phone, take a picture of the location of the plumes and screws - this will help to collect it back without errors.

Calibration of the battery for accurate readings

If the phone suddenly turns off at 10-20% charge or shows an incorrect percentage, it may require calibration of the battery controller, a process that resets data about charging cycles and restores accurate readings.

How to calibrate:

1. 🔋 Discharge your phone to 0% (until it turns off on its own).
2. 🔌 Connect to charge and wait 100% (do not turn on the phone!).
3. ⏱️ Leave it on the charger for more. 1-2 hour.
4. 🔄 Turn off the charger, turn on the phone and again discharge to 0%.
5. 🔋 Repeat the cycle 2-3 once.

💡 Important: Calibration doesn't restore capacity, it only corrects the sensor readings. If the phone still discharges quickly after the procedure, the problem is the physical wear and tear of the battery.

💡

Calibration is recommended every 3-6 months, as well as after updating the firmware or resetting settings.

Frequent questions about the Redmi Note 7 battery