The battery is one of the most vulnerable spots in the Xiaomi Redmi Note 8 Pro, especially after 2-3 years of active use. Even if the smartphone looks like new, the battery can lose up to 30-40% of its original capacity, leading to a sharp drop in autonomy.
Many users misguidedly focus on the percentage of charge in the status bar or battery life, but these numbers do not reflect real capacity — they depend on MIUI optimization, application background activity, and even ambient temperature. To make an objective diagnosis, we need special tools and methods, which we will discuss in detail below.
In this article, you will find 5 proven ways to measure the capacity of the Redmi Note 8 Pro battery – from simple (through standard settings) to advanced (using ADB and engineering menus).
1. Verification through MIUI settings (the easiest way)
If you don’t want to install third-party apps or dig through the engineering menu, start with the built-in MIUI tools. This method won’t give you accurate data on capacity in milliamp hours (mAh), but will show the overall battery health status and approximate wear.
Instructions:
- Open the Settings. → The phone.
- Tap 5-7 times on the MIUI version until the notification “You became a developer!” appears.
- Return to the main settings menu and go to Additional → For developers.
- Find the Battery Status section (may be called Battery or Health in English firmware).
Here you will see one of three meanings:
- 🟢 Good – less than 10% wear, capacity close to factory (4500 mAh).
- 🟡 Normal - wear and tear 10-30%, There is a marked reduction in working hours.
- 🔴 Bad: Wearing more than 30%, replacement is required.
⚠️ Note: In some versions MIUI This is due to Xiaomi's policy of hiding technical information in recent updates. If there is no item, move on to the next method.
The advantage of this method is that you don't have to install anything or connect the smartphone to the PC, but the data is evaluative and doesn't show the exact capacity in mAh.
2.Use of the engineering menu (#4636##)
The Engineering Menu is a hidden Android tool that provides advanced information about the hardware of the smartphone, including the battery. On the Redmi Note 8 Pro, it is available via the phone. USSD-code, but requires caution: do not change the settings unless you are sure of their purpose!
How to open it:
- Launch the Phone app.
- Enter the combination: ##4636## (no spaces).
- In the menu that opens, select Battery Information.
Here you are interested in the following parameters:
- 🔋 Level of charge (level) - current percentage.
- ⚡ Voltage - should be in the range of 3.7-4.3 V at 100% charge.
- 🔄 Temperature (Temperature) – the norm is 25–40°C (values above 45)°C critical!).
- 📊 Health - similar to the method of settings (Good/Normal/Bad).
⚠️ Note: The Redmi Note 8 Pro’s engineering menu may not have direct information about the capacity in mAh. However, the Health setting is more accurate than the standard settings, as it takes into account real-world charging cycles.
If you want specific capacity numbers, go with ADB or specialized applications, and for now, here's some useful advice:
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If the battery voltage at 100% charge is below 4.1 V, this is a sign of severe wear and tear. Try calibrating the battery: completely discharge the smartphone before turning off, then charge to 100% without interruption (preferably the original RAM).
Precise verification via ADB (for advanced users)
The Android Debug Bridge (ADB) method is the most reliable way to get real battery capacity in milliamp hours, requiring a smartphone to be connected to a PC, but providing the most accurate data, including factory and current capacity.
What you need:
- 🖥️ A computer with installed Xiaomi drivers and ADB.
- 🔌 USB-cable (preferably original).
- 📱 Initiated Debugging Mode USB smartphone.
Step-by-step:
- Download and install Google’s Platform Tools (includes ADB).
- Connect the Redmi Note 8 Pro to your PC and allow debugging (a request will appear on the smartphone screen).
- Open the command prompt (cmd) in the folder with ADB and type:
adb shell
dumpsys batteryIn the conclusion, find the lines:
- Capacity: X is the current charge in percentage.
- charge_counter: Y is the real container in microcouldons (divided into 3600, to get a mAh).
- Voltage: Z is the voltage in millivolts.
For example, if charge_counter = 16200000, that current capacity = 16200000 / 3600 ≈ 4500 mAh (factory value) If the result is less 3500 mAh - battery is severely worn out.
Install Platform Tools on PC|
Enable debugging by USB on your smartphone |
Connect the original USB-cable|
Start the command line on behalf of the administrator-->
⚠️ Attention: Meaning charge_counter It can be reset after rebooting or turning off the battery. 100% charge and do not disconnect the smartphone from the network during the test.
Critical note: On some firmware, Xiaomi blocks access to full battery data via ADB. If the dumpsys battery command outputs incomplete information, try an alternative command:
adb shell cat /sys/class/power_supply/battery/capacity
adb shell cat /sys/class/power_supply/battery/charge_full4. Capacity testing applications (AccuBattery, CPU-Z, etc.)
If ADB seems complicated, you can use third-party applications that won't give you the same accuracy as engineering methods, but they will provide enough data to estimate wear.
Top.-3 apps for Redmi Note 8 Pro:
| Annex | Pluses | Cons | precision |
|---|---|---|---|
| AccuBattery | Monitors charging cycles, shows wear, optimizes charge | Requires calibration (multiple charging cycles) | ⭐⭐⭐⭐ |
| CPU-Z | Shows voltage, temperature, battery condition | No data on capacity in mAh | ⭐⭐⭐ |
| Battery HD | Beautiful interface, history of charging | Advertising, paid functions | ⭐⭐⭐ |
How to use AccuBattery (recommended!):
- Install the app from Google Play.
- Charge your smartphone to 100% and leave it on charge for another 1 hour (for calibration).
- Use your smartphone in normal mode until discharge to 20%.
- Repeat the cycle 2-3 times - the application will show the real capacity and percentage of wear.
Example of the report from AccuBattery for Redmi Note 8 Pro:
- 📱 Factory capacity: 4500 mAh
- 🔋 Current capacity: 3800 mAh (wear and tear) ~15%)
- 🔄 Number of cycles: 312
⚠️ Attention: Apps like CPU-Z or AIDA64 Shows data from system files that may not be relevant after updates MIUI. For accuracy, use AccuBattery or ADB.
Why does AccuBattery have a lower capacity than the factory?
Physical inspection (disassembly and multimeter)
If software methods don't give a definitive answer, you can measure the capacity physically with a multimeter and completely drain the battery, which requires disassembling the smartphone and is only suitable for advanced users.
What you need:
- 🔧 Set of screwdrivers (star) T3, T4).
- 📊 Multimeter with current measurement function (10A).
- 🔌 Resistor (e.g. 10 ohms, power 5 watts).
- ⏱️ Timer (secondometry).
Instructions:
- Turn off your smartphone and remove the battery (on the Redmi Note 8 Pro, it’s glued – be careful!).
- Connect the multimeter in ammeter mode sequentially with the resistor to the battery contacts.
- Take a look at the time it takes for the voltage to drop from 4.2 V to 2.8 V (total discharge).
- Calculate the capacity by the formula: Capacity (mAh) = (Discharge current in amperes × Time in hours) × 1000
Example: if the current is discharged 0.5 A, and time. 7 o'clock, then capacity = 0.5 × 7 × 1000 = 3500 mAh.
⚠️ Warning: It is dangerous to discharge a battery below 2.8V, it can lead to irreversible damage. Also, remember that the Xiaomi Redmi Note 8 Pro has a non-removable battery: if you disassemble the battery carelessly, you risk damaging the plumes or display.
This method is as accurate as possible, but it requires electronics skills, and if you're not sure, you should go to a service center.
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Physically testing the capacity is the most reliable way, but it's also the riskiest way, and only use it if the software methods have shown critical wear and tear, and you want to confirm that you need to replace the battery.
When to change the battery: table of critical values
Even if you have measured the capacity accurately, how do you know if you need to change the battery? Below is a table with recommendations for the Redmi Note 8 Pro (factory capacity is 4500 mAh):
| Current capacity (mAh) | Percentage of wear and tear | Signs. | Recommendation |
|---|---|---|---|
| 4000–4500 | 0–10% | Normal autonomy, no sudden shutdowns | 🟢 Battery in excellent condition |
| 3500–4000 | 10–25% | Smartphone discharges faster, but holds the charge all day | 🟡 You can use it, but watch the charging cycle. |
| 3000–3500 | 25–35% | Requires recharging by evening, possible accidental shutdowns | 🟠 We recommend replacing them soon. |
| 2500–3000 | 35–50% | Battery sits down in 3-4 hours, the smartphone overheats when charging | 🔴 Replacement is needed |
| Less than 2,500. | More than 50% | The device does not hold a charge, turns off at 30-40% | 🚨 Critical wear and tear, urgent replacement. |
Additional signs that it is time to change the battery:
- 🔥 The smartphone is very hot when charging or under load.
- ⚡ Sudden spikes in percentage charge (e.g., 30% to 1% per second).
- 🔌 Slow charging (longer than 3 hours to 100 hours%).
- 📉 Battery bloating (seen by the raised display or body warping).
If you see at least 2-3 items from the list, don’t delay replacing. A worn-out battery not only spoils the user experience, but can also damage other components of a smartphone (such as the display or motherboard).