Why it’s important to watch the Xiaomi Mi 8 Pro battery – and when to sound the alarm
Xiaomi Mi 8 Pro, released in 2018, is equipped with a battery capacity of 3000 mAh with support for fast charging Quick Charge 4+. After 3-4 years of active use, even the original battery loses up to 30-40% of its original capacity - which means that the smartphone discharges 2 times faster, overheats when charging and can suddenly turn off 15-20% of the charge.
Compounding the problem, MIUI hides real battery health data in standard settings. Users often experience a phone suddenly turning off in the cold or not holding charge — and the cause is critical battery wear. In this article, we will discuss 5 working ways to check battery health, including hidden engineering menus, third-party apps and hardware tests.
⚠️ Critical signs of battery wear Mi 8 Pro:
- 🔋 Phone discharges by 10-15% in 30 minutes in standby mode
- ⚡ Charging is interrupted by 80-85% (overheating protection is triggered)
- 🌡️ Body heats up above 40°C when charging or playing
- 🔄 The percentage of charge "jumps" (for example, from 30% immediately to 10%)
- ❄️ Phone shuts down in the cold (-5°C and below)
Method 1: Hidden code of the engineering menu (#4636##)
The fastest way to get basic information about a battery is to use service code, which runs without root rights and does not require application installation.
- Open the Phone app.
- Enter the combination: ##4636###.
- In the menu that appears, select Battery Information.
In this section, pay attention to the following parameters:
- 📊 Level of charge (level) – current percentage in numbers (may differ from the indicator in the status bar).
- 🔌 Power source – Must be a battery (if connected to a charge, will be usb or ac).
- 🌡️ Temperature (Temperature) – the norm 25-35°C on standby, up to 40°C when charging/playing, if the temperature is above 45°C – the battery is degraded or malfunctioning!
- ⚡ Voltage: 3.7-4.2 V at 100% charge, below 3.5 V critical discharge.
⚠️ Note: If the menu does not open after entering the code, check whether access to engineering settings is disabled through security policies (relevant for firmware with corporate management).
💡
If the battery temperature is consistently above 40°C, try calibrating it: completely discharge the phone before turning it off, then charge to 100% without interruption. Repeat 2-3 times.
Method 2: AccuBattery App - Detailed Wear Analysis
AccuBattery (available on Google Play) is one of the few apps that shows real battery wear as a percentage rather than abstract “health scores.” For the Xiaomi Mi 8 Pro, it’s especially useful because it can bypass MIUI’s limitations on battery data.
How to use:
- Install and open AccuBattery.
- Connect your phone to charging and wait until the application collects data (you need at least 2-3 charge/discharge cycles).
- Go to the Health tab, and it shows here:
| Parameter | Normal for Mi 8 Pro | Critical significance |
|---|---|---|
| Battery capacity | 2800-3000 mAh | < 2000 mAh (65% of the original) |
| Wearing | 10–20% | > 40% |
| Temperature during charging | 35–40°C | > 45°C |
| Standby discharge speed | 0.5-1% per hour | > 3% per hour |
🔹 Important: AccuBattery is designed to have a capacity, not a factory capacity. If it's below 2,500 mAh, the battery needs to be replaced.
Turn off battery optimization for the application in MIUI | settings
Charge your phone to 100% without using |
Do not interrupt the charging/discharge cycle |
Repeat the test 2-3 times for accuracy-->
Method 3: ADB-Teams for Advanced Users
If the engineering menus and apps don't give you the full picture, you can use ADB (Android Debug Bridge) to get raw data from the battery controller, a method that requires a PC and minimal command-line skills.
Instructions:
- Download ADB Tools and unpack it into a folder.
- Turn on USB Debugging on your phone: Settings → About Phone → MIUI Version (click 7 times), then Settings → Additional → For Developers → Debugging over USB.
- Connect the Mi 8 Pro to your PC and execute:
adb shell
dumpsys batteryIn conclusion, note:
- 📋 capacity - current capacity in mAh (compare with passport 3000 mAh).
- 🔄 charge counter – the number of full charging cycles (norm – up to 500).
- 🌡️ Temperature - temperature in tenths °C (e.g, 345 = 34.5°C).
- ⚡ Voltage - voltage in microvolts (4200000 = 4.2 V).
⚠️ Note: If the health parameter is relevant COLD, OVERHEAT or DEAD, The battery is defective and needs immediate replacement. GOOD It does not guarantee the absence of wear and tear, it only means that the controller does not detect critical errors.
What if the ADB does not recognize the device?
Method 4: Multimeter Test – Testing voltage and current
If software methods don't give a definitive answer, you can measure the actual electrical parameters of the battery with a multimeter, which is the most accurate way, but requires disassembling the phone.
What you need:
- 🔧 Multimeter (with constant voltage measurement mode up to 20 V).
- 🔌 Thin probes or needles.
- 🛠️ Plastic blade for disassembly.
Procedure:
- Turn off the phone and remove the back cover (on the Mi 8 Pro it is glued - gently tuck around the perimeter).
- Disconnect the battery plume from the motherboard (usually it is fixed by the connector).
- Connect the multimeter probes to the battery contacts (+ and -).
- Measure the voltage:
| Charge level | Normal tension | Critical tension |
|---|---|---|
| 100% | 4.2–4.3 In | < 4.0 Included |
| 50% | 3.7–3.8 | < 3.5 V |
| 0% | 3.0-3.2 V | < 2.8 V (deep discharge!) |
🔹 Important: If the voltage on a fully charged battery is below 4.0V, its capacity is critically reduced. If below 3.5V, the battery is damaged and may swell.
⚠️ Warning: Don't touch the other components of the board with probes - this can cause a short circuit! If the battery is swelling (as seen from the deformation of the lid), do not try to test it - immediately take the phone to the service!
Method 5: Visual Diagnostics – When to Run to the Service
Some battery problems with the Xiaomi Mi 8 Pro can be detected without tools, just by carefully examining the phone.
- 📱 Bloating: If the back cover or screen is raised and the phone is worse on the table, the battery is bloated!
- 🔥 Overheating: If the phone heats up to 50°C and higher when charging or simple tasks (such as calls), this is a sign of battery degradation or controller failure.
- ⚡ Uneven charging: if the charge indicator is stuck by 80-85%, the protection against overheating is triggered. Try charging the phone when it is turned off - if the percentage reaches 100%, the problem is in the software or battery.
- 🔋 Sudden shutdowns: If the phone is turned off at 15-30% charge, this means that the actual battery capacity is below the shutdown threshold (usually 3.2-3.4 V).
📌 Checklist for visual inspection:
Check if the phone is on the table (no swelling)|
Check the charging connector for oxidation |
Try charging your phone with another cable/power supply |
Check if the screen is floating when pressed (a sign of a bloated battery)-->
If you find any of these signs, don't delay replacing the battery. A billowing battery can damage the screen, the motherboard, and even cause a fire.
How to extend the life of the battery Xiaomi Mi 8 Pro: 7 rules
Even if the battery is still in good condition, following simple rules will help delay its replacement by 1-2 years:
- 🔌 Use an original or certified power supply with Quick Charge 4 support+. Cheap charging overheats the battery.
- 🌡️ Avoid extreme temperatures: Do not leave your phone in the sun or in your car in the summer, do not charge at temperatures below 0°C.
- 🔋 Keep the charge in the range of 20-80%: full cycles (0-100%) reduce the lifespan. In AccuBattery settings, you can turn on a notification when you reach 80%.
- 📵 Disable unnecessary functions: GPS, NFC, Automatic synchronization in the background discharges the battery once again.
- 🔄 Calibrate the battery once every 3 months: completely discharge the phone, then charge to 100% without interruptions.
- 🛡️ Update: In new versions MIUI Optimize energy consumption. Current firmware for the Mi 8 Pro — MIUI 14 (Android 10).
- 🚫 Do not use your phone while charging for games or videos – this increases battery heat.
💡
The optimal charging mode for the Mi 8 Pro is 0.5-1A (standard 18W adapter). Fast charging speeds up wear, so use it only when necessary.