Why is it important to monitor the battery status of the Redmi Note 8?
The battery is one of the most vulnerable components of the smartphone, and Xiaomi Redmi Note 8 is no exception. Over time, the battery capacity decreases: if the new device held a charge for a day, then after 2-3 years it can discharge in a few hours. The causes of degradation are diverse, from natural wear to improper charging or overheating. For example, the constant use of fast charging on 18W accelerates the wear of lithium polymer cells, and a discharge below 15% increases the load on the power controller.
Battery problems are not just about fast discharge. A smartphone can spontaneously shut down at 30-40% charge, overheat during charging or playing, and sometimes even swell (which is dangerous for the screen and motherboard). In this article, we’ll look at 5 reliable ways to test a battery, from built-in MIUI tools to third-party apps and physical inspection. You’ll learn how to interpret wear metrics, when it’s time to change the battery, and how to prolong its life.
The Redmi Note 8 features a 4,000 mAh battery that is not removable, making it difficult to replace, so early diagnosis can avoid costly repairs, such as if the wear has exceeded 30%, it is recommended to plan a replacement within six months to avoid sudden device failure.
Method 1: Check through hidden engineering menu (#4636##)
The fastest method is to use the built-in Android engineering menu, which is available on all Xiaomi smartphones, including the Redmi Note 8, and does not require the installation of additional applications.
- Open the Phone app.
- Enter the combination: ##4636###.
- In the menu that appears, select Battery Information.
In this section you will see the key parameters:
- 🔋 Level of charge (level) – current percentage in digital form (may differ from the one displayed in the status bar).
- 🔌 Status Charging (charged), Discharging (discharged) or Not charging (no power).
- 🌡️ Temperature – Optimal range of 25–40°C. Exceeding 45°C critically!
- 📊 Voltage – should be within 3.7–4.2V fully charged.
⚠️ Warning: If the battery temperature exceeds 50°C in normal use (not during charging or gaming), this is a sign of critical wear or failure of the controller!
Method limitation: the engineering menu doesn't show actual capacity or percentage of wear. It will require other tools (see below), but it can quickly detect overheating or unstable voltage, the first signs of problems.
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If the engineering menu doesn't open, check to see if the hidden settings in Settings → Special Features → Developer Menu is disabled. Turn on USB Debugging and try again.
Method 2: Using AccuBattery for detailed diagnostics
AccuBattery (available on Google Play) is one of the most accurate tools for analyzing battery status. It tracks charging cycles, measures real capacity, and predicts the remaining battery life. This is especially true for the Redmi Note 8, as it takes into account the features of Xiaomi's lithium polymer batteries.
How to use:
- Install AccuBattery from Google Play.
- Charge your smartphone to 100% and discharge to 0% (before automatically shutting down).
- Open the app and go to the Health tab.
In the Health section, pay attention to:
- 📉 Estimated capacity: The actual battery capacity in mAh. For example, if it was originally 4,000 mAh, now it's 3200 mAh, the wear was 20%.
- 🔄 Number of charging cycles – each full cycle (0 to 100%) reduces battery life. After 500 cycles, the capacity usually drops to 80%.
- ⚡ Charging/discharge speed – if the discharge is too fast (e.g. 10% per hour in standby mode), it is a sign of wear and tear.
| Indicator. | Norma. | Critical significance |
|---|---|---|
| Battery wear and tear | 15% | 30% |
| Temperature during charging | 40°C | more than 50°C |
| Discharge speed in anticipation | up to 1% per hour | more than 5% per hour |
| Voltage at 100% charge | 4.2–4.3V | more than 4.4V or less than 4.0V |
AccuBattery shows the most accurate data after 3-5 full charge-discharge cycles. If after the first test the capacity seems to be understated, repeat the procedure.
Method 3: Checking with MIUI Battery Care (built-in utility)
Starting with MIUI 12, Xiaomi has added a built-in Battery Care tool that analyzes battery status and offers recommendations.This method doesn't require installing third-party apps and is suitable for users who don't want to go into technical details.
How to find Battery Care:
- Open the Settings.
- Go to the battery and performance.
- Put it on the icon. ⚙️ (Battery settings).
- Choose Battery Care (Battery Care).
In this section you will see:
- 📊 Battery status – Good to Critical.
- 🔋 Charging recommendations – for example, tips to avoid overheating or use the original adapter.
- 📅 Usage statistics – screen time, most energy-consuming applications.
⚠️ Attention: In some firmware MIUI Battery Care may not be available. If not, upgrade to the latest version or use alternative methods (e.g. AccuBattery).
The advantage of this method is that it's simple and integrated with the system, but the data here is less detailed than in AccuBattery. For example, you won't see the exact capacity in mAh, but you'll get a general idea of the battery's health and tips for keeping it.
☑️ Preparation for battery testing
Method 4: Visual examination and physical diagnosis
Sometimes battery problems are visible to the naked eye, a physical exam will help identify critical malfunctions that are not displayed in software tests, and for the Redmi Note 8, this is especially true, since its non-removable battery can deform over time.
Signs of malfunction:
- 🔍 Bloating - if the back cover or screen starts to "go away", it is a sign of a bloated battery!
- 🔥 Overheating without loading – if the phone is heated in standby mode, it may indicate a short circuit inside the battery.
- ⚡ Uneven charging – for example, the charge “stuck” by 80% or jumps from 50% to 20%.
- 🔌 Charging port problems – if the cable is not holding or charging is only in a certain position, this may be due to the deformation of the battery pressing on the connector.
How to do the inspection:
- Put your smartphone on a flat surface and check if it is swinging (a sign of bloating).
- Check the case for gaps between the screen and the frame.
- Feel the back cover – if it is “soft” or convex, the battery is swollen.
⚠️ Warning: If you find a battery bloating, do not attempt to puncture or bend it! Lithium polymer batteries may ignite if damaged. Contact a replacement service center.
For a deeper diagnosis, you can use a multimeter (if you have experience with electronics), measure the voltage at the contacts of the battery when fully charged - it should be in the range of 4.2-4.3V. If the voltage is below 3.5V, the battery is deeply discharged and may not recover.
What to do if the battery is swelling?
Method 5: Testing with ADB (for advanced users)
If you're familiar with Android Debug Bridge (ADB), you can get detailed battery information through the command line, a technique that's suitable for tech-savvy users, as it requires a PC connection and knowledge of basic commands.
Instructions:
- Turn on USB Debugging in Settings → About Phone → MIUI version (shap 7 times, then go back to Additional Settings → For Developers).
- Connect Redmi Note 8 to your PC and open the terminal (or Command Prompt on Windows).
- Enter the command: adb shell dumpsy battery
In the conclusion of the command, pay attention to the following parameters:
- 📋 Level - current level of charge in percentage.
- 🔌 status (2) = Charging, 3 = discharge).
- 🌡️ Temperature: Temperature in tenths of a degree (e.g, 320 = 32.0°C).
- ⚡ Voltage - Microvoltage (divided by 1000 to get volts).
- 🔄 charge counter - charge counter in microamper-hours (divided by 1000 for mAh).
Example of conclusion:
level: 85
status: 2
temperature: 310
voltage: 4120 (4.12V)
charge counter: 3200000 (3200 mAh)Compare charge counter to rated capacity (4,000 mAh for the Redmi Note 8) If the difference is greater than 20%, the battery is worn out. This method is more accurate than the engineering menu, because it shows real capacity, not just voltage.
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ADB-Testing is the most accurate way to determine the actual capacity of the battery, but requires command line skills.
When is the time to change the battery to the Redmi Note 8?
Even if the battery is still holding a charge, there are signs that it should be replaced.
| Sign. | Action. |
|---|---|
| Wearing more than 30% (accuBattery or ADB) | Plan a replacement within 3-6 months |
| Working hours were halved (for example, instead of 12 hours – 4-5). | Replacement recommended |
| The smartphone turns off at 20-30% charge | Critical wear and need replacement |
| Bloating or overheating without loading | Immediate replacement! Risk of damage to the device |
| Charging is only in a certain position of the cable. | Check the battery and charging port |
The cost of replacing the battery on the Redmi Note 8 in Xiaomi service centers is about 1500-2500 rubles (2026). Self-replacement will cost less (800-1200 rubles per battery), but requires experience: you need to carefully disconnect the plumes and do not damage the adhesive base.
If you choose to change the battery yourself, choose original or certified counterparts (such as from ZMI or Baseus). Cheap non-original batteries may have lower capacity or work incorrectly with the Xiaomi charging controller.
How to extend the life of the Redmi Note 8 battery?
Even if the battery is still in good condition, following a few rules will help delay its wear and tear:
- 🔌 Use the original adapter on the 18W. Fast charging is convenient, but the constant use of powerful power supplies accelerates degradation.
- 📱 Avoid full discharge. Optimal range is 20-80%. Regular discharges to 0% reduce battery life.
- 🌡️ Do not overheat the device. Do not leave your smartphone in the sun or near heat sources. 4K heat the processor, which affects the battery.
- 🔄 Calibrate the battery once every 3 months: fully discharge, then charge to 100% without interruptions.
- 🛌 Keep your smartphone with a charge of 40-60% if you do not use it for a long time (for example, during vacations).
It is also useful to turn off background activity of unnecessary applications. To do this, go to Settings → Battery → Battery use and limit power consumption for underutilized programs.
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MIUI has Smart Charging, which automatically stops charging by 80% and then up to 100% before waking up, and turn it on to Settings → Battery → Battery Care.