Xiaomi Redmi Note 8 is one of the most popular smartphones in the budget segment, but over time, even its capacious battery of 4000 mAh begins to lose capacity. If the phone runs out too quickly, turns off by 20-30% or overheats when charging, itβs time to diagnose the battery. In this article, 5 proven ways to find out the real status of the battery, including hidden engineering menus, third-party applications and data analysis through ADB.
We're going to not only look at how to see battery wear, but also what to do with the data: when to change the battery, how to reset the charging cycle statistics and why MIUI figures can lie. All the instructions are relevant for the Redmi Note 8 (the ginkgo model) on any firmware version, including MIUI 12/13/14 and custom builds.
1. Check through the hidden menu ##4636##
The fastest way to get basic information about a battery is to use the Android Engineering Menu, which is available without root rights or additional apps, but shows limited data.
How to open it:
- π± Open the phone application (calling).
- π’ Enter the combination: ##4636##.
- π Select the Battery Information tab).
On this menu you will see:
- π Level of charge (level) - current percentage.
- π Power source: battery (from battery) or USB/AC (charge-free).
- π‘οΈ Temperature: in tenths of a degree Celsius (for example, 325 = 32.5Β°C).
- β‘ Voltage β should be in the range of 3.7-4.3 V when fully charged.
β οΈ Warning: If the voltage is below 3.5 V at 100% charge or the temperature is above 45Β°C in simple β the battery is critically worn and needs replacement.
The downside of this method is that the menu doesn't show the capacity or the number of charging cycles. For a deep diagnosis, use the following methods.
Code ##6484## - Battery and hardware test
The service code for Xiaomi devices allows you to run an automatic test of the battery and other components, which is more informative than the standard engineering menu, but does not work on all firmware.
Instructions:
- Open the phone and type in ##6484##.
- From the Manual Test menu, select Battery.
- Press the Start Test and wait for the results (10-30 seconds).
In the results, pay attention to:
- π Health - battery status (Good/Unknown/Replace).
- π Charge cycles β number of full charging cycles (normal up to 500).
- π Capacity - current capacity in mAh (compare with factory 4000 mAh).
β οΈ Note: If Unknown is in the Health column, it doesnβt always mean a malfunction, as it happens on custom firmware. Use AccuBattery for accurate diagnosis (see section 4).
On some versions of MIUI, this code may not work, and the alternative is code ##64663## (hardware component test), which also includes battery checks.
π‘
If the code doesnβt work, try typing it without stars: #6484# or adding a space after the bar: # *6484#.
Data via ADB: How to find out the real capacity of the battery
For advanced users, the most accurate method is readable data via ADB (Android Debug Bridge), which shows the actual battery capacity per mAh, the number of charging cycles, and even the date of first use (if the statistics were not reset).
What you need:
- π» Computer with installed ADB Tools.
- π USB-cable (preferably original).
- βοΈ Included debugging by USB (How to turn on - see spoiler below).
How to enable USB debugging on Redmi Note 8
Instructions for data acquisition:
- Connect the phone to the PC and allow debugging (on the smartphone screen will appear a request).
- Open the command prompt (cmd) in the folder with ADB.
- Enter the commands in turn: adb shell dumpsy battery
In the conclusion, find the lines:
- Capacity: Current charge in %.
- charge counter: - real capacity in ΞΌAh (divide by 1000 to get mAh).
- cycle_count: β charge-cycle.
| Parameter | Normal for Redmi Note 8 | Critical significance |
|---|---|---|
| charge counter (mAh) | 3800β4000 | < 2500 |
| cycle_count | < 500 | > 800 |
| temperature (Β°C) | 25β40 | > 45 |
| voltage (B) | 3.7β4.3 | < 3.5 or > 4.4 |
If the charge counter shows less than 3000 mAh, the battery is worn out by 25% or more - it's time to think about replacing.
π‘
ADB provides the most accurate data, but requires command line skills. It is easier for beginners to use applications like AccuBattery (see next section).
4.AccumBattery application: monitoring battery wear and health
AccuBattery is a free (premium) application that analyzes battery status based on charging/discharge data, which does not require root rights and is suitable for beginners.
How to use:
- Install AccuBattery from Google Play.
- Charge your phone to 100% and leave it on charge for another 15-20 minutes (for calibration).
- Use your smartphone as usual until the charge drops to 20-30%.
- Open the app and go to the Health tab.
What AccuBattery shows:
- π Design capacity - compared with the factory (4000 mAh).
- π The number of cycles is approximate (more precisely only through the ADB).
- π Depreciation - in percentages (norm to 15-20%).
- β‘ Charging/discharge speed β helps identify βgluttonousβ applications.
Example of data interpretation:
- π΄ Capacity 2800 mAh β wear ~30%, replacement is required.
- π‘ Capacity 3200-3500 mAh β 10-20% wear, can be operated, but monitor the temperature.
- π’ Capacity 3800+ mAhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh β battery in good condition.
Calibrate the battery (discharge to 0% and charge to 100% without interruption)|
Check the temperature during charging (not higher than 40Β°C) |
Turn off fast charging in MIUI | settings
Use the original power supply unit (5V/2A or 9V/2A)-->
5. Reset battery statistics: when and how to do
Sometimes MIUIs show an incorrect percentage of charge due to a downed calibration, such as a phone that shuts down by 30 percent or jumps from 50 percent to 20 percent, and then resetting the battery statistics helps.
How to reset:
- Charge your phone to 100% and disconnect from the network.
- Use your phone until it is completely discharged (until it turns off).
- Connect to charging and charge up to 100% without interruptions (at least 3 hours).
- Reset with ADB (optional): Adb shell dumpsys batterystats --reset
β οΈ Attention: Resetting the statistics doesn't restore the battery capacity! It only corrects the charge display errors. If after calibration the phone still discharges quickly, the problem is the physical wear and tear of the battery.
Alternative method (without ADB):
- Go to Settings. β Battery.
- Slap the icon. βοΈ (battery settings).
- Select Reset Statistics (if the option is available).
After reset, monitor the battery for 2-3 days. If there is no improvement, check the wear through AccuBattery or ADB.
Physical Diagnostics: When to Change the Battery
Even if software tests show normal values, physical signs often indicate battery wear earlier than software.
- π₯ Overheating β if the body is heated above 40Β°C to simple (check in ##4636##).
- π Sudden shutdowns β for example, 30-40% of the charge.
- π’ Slow charging β if 0% to 100% longer than 3 hours (with the original power supply).
- π₯ Battery bloating β check if the screen or back cover is moving away (especially dangerous!).
If you notice any of these signs, don't delay replacing them. A worn-out battery not only shortens your life, but it can also:
- Damage the motherboard due to unstable stress.
- It is a fire (rarely, but there is a risk).
- Reduce performance due to constant trottling (processor frequency reset).
The cost of the original battery for the Redmi Note 8 β from 1500β2500 β½ (You can make the replacement yourself (youtube guides are available) or at a service center, but you can only buy the original battery with the label. BM47 or BM48 (For the Redmi Note 8/8T).
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If the battery is swollen, turn off the phone immediately and don't try to charge! The billowing battery can damage the screen or burst when heated.