How to know exactly the status of the battery on Xiaomi Redmi 9: Step-by-step instructions

The battery is one of the most vulnerable components of the smartphone, and Xiaomi Redmi 9 is no exception. After 1-2 years of active use, the battery capacity begins to decline, leading to rapid discharge, sudden shutdowns and charging problems. But how to objectively assess its condition without disassembling the phone? In this article, we will analyze all available methods, from hidden MIUI menus to specialized applications that will show real wear, the number of charging cycles and current capacity in milliamp hours (mAh).

It’s important to understand that battery performance is not only time-dependent, but also usage-specific: frequent overheating, charging with “cheap” adapters, or a full discharge of up to 0% accelerate degradation. We’re not going to limit ourselves to superficial tips like “look in the settings” – instead, you’ll get specific commands, menu screenshots, and an explanation of what indicators are considered critical for the Redmi 9 (M2003J15SC model and analogues).

1. Check through the engineering menu (#4636##)

The fastest way to get basic information about a battery is to use a hidden engineering menu, which is available on all Xiaomi smartphones without any additional apps or root rights.

1. Open the Phone app.
2. Enter the combination: ##4636###.
3. In the menu that appears, select Battery Information.

Here you will see the following key parameters:

• 🔋 Level of charge (level) – current percentage in digital form.
• 🔌 Power source – shows whether the phone is connected to charging (USB or AC).
• 🌡️ Temperature: critical if the value exceeds 40°C (when charging) or 45°C (under load).
• ⚡ Voltage: The norm for Redmi 9 is 3.7–4.4V.

Now, notice that this menu doesn't show wear or actual capacity, it's just the current state, and for a deep diagnosis, you'll need other methods, which I'll talk about later.

Code for checking the number of charging cycles (##6484##)

One of the least known but useful codes for Xiaomi is ##6484##. It opens the MTK Engineer Mode menu (available on the MediaTek processors used in the Redmi 9), and you can see how many times the battery has been fully discharged and charged, which directly affects its life.

Instructions:

1. Enter the dialer: ##6484##.
2. Go to the Battery section.
3. Find Battery Charge Cycle, which shows the number of cycles.

For reference:

• 📊 0-300 cycles – battery in good condition.
• ⚠️ 300–500 cycles – a noticeable decrease in capacity (by 15–30%).
• ❌ 500+ cycles - critical wear, it is recommended to replace.

💡

If ##6484## doesn't work, try the alternative: #36446337## (for some versions of MIUI).

Important: some Xiaomi firmwares may block this code, so if the menu doesn't open, use the methods in the following sections.

3.AccumBattery application: detailed wear analysis

If standard methods don't give you the full picture, AccuBattery (available on Google Play) will come to the rescue, not only showing current capacity, but also tracking discharge rate, temperature, and even predicting the remaining battery life.

How to use:

1. Install and open AccuBattery.
2. Go through the initial setup (specify the real capacity of the Redmi 9 battery – 5020 mAh).
3. Go to the Health tab – here you will see the percentage of wear.

What do indicators mean?

AccuBattery also shows real capacity (e.g., 4200 mAh instead of the claimed 5020 mAh), which helps to estimate how much the battery has degraded.

Charge your phone to 100% |Distribute to 15-20% without recharging |Repeat cycle 2-3 times for accurate data |Do not use your phone during the test (ideally leave overnight)

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Checking through MIUI Battery Care (built-in function)

Starting with MIUI 12.5, Xiaomi added a built-in battery monitoring tool, Battery Care, which is less accurate than AccuBattery, but does not require third-party apps to be installed.

1. Go to Settings → Battery and Performance.
2. Put it on the icon. ⚙️ (Battery settings) in upper right corner.
3. Select Battery Health (Battery Health) status.

Here you'll see:

• 📉 Total depreciation (percentage).
• 🔄 Number of complete charging cycles.
• 📊 Degradation schedule (if the function is supported by your version) MIUI).

Method limitation: Some firmware versions may not have this partition or show incomplete data. If you have Redmi 9 on MIUI 11 or lower, upgrade or use alternative methods.

5. Diagnostics via ADB (for advanced users)

If you're willing to use a developer tool, ADB (Android Debug Bridge) will give you the most accurate data on the battery, which requires you to connect your phone to your computer, but it gives you access to hidden parameters that the application doesn't show.

Step-by-step:

1. Enable USB debugging in the developer settings (Settings → About Phone → MIUI version – tap 7 times, then go back to Additional settings → For Developers).
2. Connect Redmi 9 to your PC and confirm debugging permission.
3. Open the command line (Windows) or terminal (macOS/Linux) and type:

adb shell


dumpsys battery

In conclusion, pay attention to the following lines:

• Health - battery status (2 = good, 3 = overheating, 4 = dead).
• Capacity is the current capacity as a percentage of the factory capacity.
• charge counter is the actual charge in microcoulombs (divide by 3600 to get mAh).

Example of conclusion:

health: 2


capacity: 85




charge counter: 18072000

This means that the battery is in good health condition (health: 2), but its capacity has decreased to 85% of the original capacity (i.e. from 5020 mAh to ~4267 mAh).

💡

ADB is the most accurate method, but requires command line skills. If you've never used ADB, you'd better choose the simpler methods from this article.

6.Physical Diagnostics: When to Disassemble Your Phone

If the software methods show critical wear and tear, but you doubt their accuracy, the last thing you can do is visual inspection.

• 🔥 The phone is very warm even without loading.
• 💥 The battery swelled (the body deformed).
• ⚡ Charging is jerky or the phone shuts down at 20-30%.

For inspection:

1. Turn off the phone and remove the tray for SIM-map.
2. Illuminate a flashlight along the seams of the back cover - if the battery is swelling, a gap will be visible.
3. Carefully press the screen at the edges: a deflection indicates a deformation of the battery.

⚠️ Warning: If the battery is swelling, you can't keep using it! There's a high risk of fire or damage to the internal components.

Replacing the battery with Redmi 9 will require:

• 🔧 Special suction cup and plastic mediator to open the lid.
• 🔋 Original battery (article: MB11 or DM-09 for the version at 5020 mAh).
• 🛠️ Clay. B-7000 or double-sided tape to fix a new battery.

Replacement cost at the service center: 1500-2500 ₽ (Self-replacement is possible, but requires care - the risk of damage to the plumes or display.

FAQ: Frequent questions about Xiaomi Redmi battery 9