A ​​smartphone battery is one of the most vulnerable components, which degrades even with careful use. After 1–2 years of active use, the battery capacity may decrease by 20–30%, which leads to rapid discharge, sudden shutdowns and charging problems. But how can you find out exactly how worn out the battery of your Androiddevice is?

In this article we will analyze all the available ways to check battery wear - from built-in tools from manufacturers to hidden engineering menus and third-party applications. You will learn which parameters are important for diagnostics (charging cycles, real capacity, internal resistance), how to interpret them and what to do if the battery is critically worn out. The instructions are suitable for devices Samsung, Xiaomi, Google Pixel, OnePlus and other brands based on Android 10–14.

We warn you in advance: some methods require root access or connecting to a PC. If you are not ready for technical manipulations, use simple applications from Google Play, which we will also consider.

📊 How often do you check the battery status?
Never
Once every six months
Only when problems start
After each major Android update

1. Manufacturers' built-in tools

Many brands add hidden menus or separate sections for battery diagnostics to the firmware. These tools are the most reliable, since they pull data directly from the power controller, and do not evaluate indirect indicators.

For example, Samsung has a service menu ##4636##, and Xiaomi has a built-in utility CIT (in some models). Below are instructions for popular brands.

  • 📱 Samsung (One UI): Enter ##4636##in the dialer, select Battery information. Here charge level, temperature, voltage and technology (Li-ion/Li-Po) are displayed. For new models (with Android 13), a code may be required #0# → Battery.
  • 🔧 Xiaomi/Redmi/Poco: Go to Settings → About phone → All specifications → MIUI version. Press 5 times on MIUI Version, then enter in the dialer ##4636## or use the application CIT (if preinstalled).
  • 🤖 Google Pixel: Hold 1 on the dialer to open Field Test Mode. An alternative is the application Device Health Services (pre-installed on new models).
  • ⚡ OnePlus/Oppo/Realme: Enter #808#, select Hardware Testing → Battery. Code may be required for ColorOS 13+ Built-in tools often show only basic data (voltage, temperature), but not #36446337#.

Limitation: Built-in tools often show only basic data (voltage, temperature) but not real capacity or number of charging cycles. For deep diagnostics, third-party methods will be required.

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If the codes do not work, try adding a symbol # at the end (for example, ##4636###). On some firmware, manufacturers block engineering menus for ordinary users.

2. Applications for checking battery wear

If your smartphone does not have built-in tools or they are too limited, third-party applications will come to the rescue. We have selected the most accurate and safe options from Google Playthat do not require root access.

Application Accuracy Requires root? Features
AccuBattery ⭐⭐⭐⭐ ❌ No Shows real capacity, wear, temperature i discharge rate. Works on most devices.
Battery Guru ⭐⭐⭐ ❌ No Monitors charging cycles and offers tips for extending service life. Supports widgets.
CPU-Z ⭐⭐ ❌ No Shows basic information about the battery (technology, voltage, temperature), but does not evaluate wear.
3C Battery Monitor ⭐⭐⭐⭐⭐ ⚠️ Partially The most accurate application, but for full functionality you need root or ADB. Shows full report with graphs.

How to use AccuBattery (step by step):

  1. Install the application and allow access to battery data.
  2. Charge your phone to 100% and wait for the “Charging complete” notification.
  3. Go to the tab Health - it will display calculated capacity and percentage wear.
  4. For accuracy, use the application 2-3 charge cycles.

Charge the phone to 100%|Calibrate the battery (discharge to 0% and charge without interruption)|Disable battery optimization for the application|Do not use the phone during the test-->

Important: Applications without root access estimate wear indirectly (based on discharge time, voltage, etc.), so the error can reach 10–15%. For accurate diagnostics, use methods with ADB or the engineering menu.

3. Check via ADB (without root)

ADB (Android Debug Bridge) is a debugging tool that allows you to get battery data directly from the system. The method works on any Androiddevice without root access, but requires connection to a PC.

What you will need:

  • 🖥️ Computer with Windows/macOS/Linux.
  • 🔌 Cable USB-Type C (original to avoid connection problems).
  • 🛠️ Installed drivers ADB i Fastboot (you can download from the website Google).
  • 📱 Enabled USB debugging on the phone (Settings → About phone → Number assembly → press 7 times → return to Settings → System → For developers).

Instructions:

  1. Connect the phone to the PC and confirm permission to debug.
  2. Open the command line (cmd in Windows or Terminal in macOS/Linux) and enter: 
    adb shell dumpsys battery
  3. Find the lines in the output: 
    capacity: 3500

    charge counter: 3200

    Here capacity is nominal capacity (according to the passport), and charge counter — real capacity at the moment.

  4. Calculate wear by formula: 
    Wear (%) = (1 - (charge counter / capacity)) × 100

    For example, if capacity=3500, and charge counter=2800, then wear = 20%.

What to do if ADB does not recognize the device?

1. Check if USB debugging is enabled (Settings → For Developers).

2. Install drivers for your model (for example Samsung USB Driver for Samsung devices).

3. Try a different cable or USB port.

4. Restart your phone and PC.

5. Enter in the command line:

adb kill-server

adb start-server

⚠️ Attention: Some manufacturers (for example, Huawei or Xiaomi on MIUI 14+) batteries via ADB. In this case, you will have to use root or specialized applications.

4. Engineering menu (for advanced users)

Engineering menu (Engineer Mode or MTK Engineer Mode) is a hidden section of the firmware where all the technical data of the device is collected, including detailed information about the battery. It can be accessed through special codes or applications.

How to open the engineering menu:

  • 📞 For Mediatek (MTK): Enter ##36446337## or ##4636## → Battery Information.
  • 🤖 For Qualcomm Snapdragon: Enter ##7378423## → Service tests → Battery.
  • 🔧 For Exynos (Samsung): Use code *#0228# (shows voltage, current i temperature).

In the engineering menu, pay attention to the following parameters:

  • Battery Capacity (mAh) — actual capacity.
  • Voltage (mV) —voltage (norm: 3700–4200 mV for Li-ion).
  • Temperature (°C) —temperature (optimally: 20–40°C).
  • Charging Cycles —number of charging cycles (critical if > 500).
  • Impedance (mΩ) —internal resistance (the higher, the worse the condition of the battery).

Example of interpretation data:

If the menu indicates Battery Capacity: 2800 mAh, and the battery case says 3500 mAh, then the wear is ~20%. If Impedance > 200 mΩ, the battery is severely degraded and may swell.

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The engineering menu is the most accurate way to check without root, but incorrect actions (for example, changing settings) can lead to malfunctions of the phone. Do not change the parameters if you are not sure of their purpose!

5. Physical inspection of the battery (visual signs of wear)

Even without special tools, you can suspect problems with the battery. by external signs. If you notice at least one of the listed symptoms, most likely the battery requires replacement.

  • 🔋 Bloating of the case: The phone no longer lies flat on the table, the screen or back cover “moves away” from the frame. Dangerous! ignite.
  • ⚡ Sudden charge jumps: For example, the level drops from 50% to 15% in a few minutes or the phone turns off at 20-30% charge.
  • 🔥 Overheating: The battery heats up even under minimal load (for example, during a call or browsing video).
  • ⏳ Accelerated discharge: The phone discharges in 2-3 hours with normal use (previously it held the charge all day).
  • 🔌 Charging problems: The device does not charge to 100%, charging is interrupted or goes too long slowly.

⚠️ Warning: If the battery is swollen, Do not attempt to puncture, heat, or continue to use it. Unplug your phone, remove the battery (if possible) and dispose of it at a designated collection point. Lithium batteries may ignite or explode if damaged.

How to check for bloating:

  1. Put the phone on a flat surface (e.g. table).
  2. Lightly press the screen or back cover along the edges.
  3. If the case “plays” or a bulge is felt under your finger, the battery is swollen.
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To check for swelling, you can use level for construction work (apply to the back cover). If the phone shakes, the battery is deformed.

6. When is it time to change the battery?

Even if the battery is not swollen, it should be replaced when the following indicators occur:

Parameter Critical value What does this mean
Wear (%). (mΩ) > 30% The capacity has dropped by a third, the phone is discharged in a few hours.
Number of cycles > 500 Lithium batteries are designed to last 500–1000 cycles before degrading.
Internal resistance (mΩ) > 200 High resistance leads to overheating and rapid discharge.
Battery life < 2 hours With normal use (social networks, instant messengers, calls).

Battery replacement cost:

  • 💰 Samsung: 2,000–5,000 ₽ (original) / 1,000–2,500 ₽ (analog).
  • 💰 Xiaomi/Redmi: 1 500–3 500 ₽.
  • 💰 Google Pixel: 3,000–6,000 ₽ (due to the complexity of disassembly).
  • 💰 OnePlus: 2 500–4 500 ₽.

⚠️ Attention: Cheap battery analogues often have a lower capacity and can fail faster. When replacing in an unofficial service, make sure that they use high-quality batteries (for example, with marking ATL or SDI).

7. How to extend the life of the battery?

Even if the battery is still in good condition, following simple rules will help delay it degradation:

  • 🔌 Avoid full discharge: Optimal charge range - 20–80%. Regular discharges to 0% reduce the service life.
  • ☀️ Do not overheat the phone: Do not leave it in the sun, under a pillow or near heat sources. — 10–35°C.
  • ⚡ Use original chargers: Cheap chargers can supply unstable voltage, which harms the battery.
  • 📵 Disable unnecessary functions: GPS, NFC, 5G and background activity of applications if they are not needed.
  • 🔄 Calibrate the battery: Once every 2-3 months, completely discharge the phone until it turns off, then charge it to 100% without interruptions.
  • 🛌 Keep your phone half-charged: If you do not use it for a long time (for example, in a warehouse), leave the charge at level 40–60%.

Myths about batteries that you should not believe:

  • ❌ “You should always charge to 100%” - on the contrary, this shortens the service life.
  • ❌ “Fast charging spoils the battery" - modern controllers regulate the current, but constant use fast charging can accelerate wear.
  • ❌ “The phone must be discharged to 0% once a month” - this was true for nickel batteries, but not for lithium ones.
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The most harmful factor for the battery is - high temperature. If the phone heats up while charging, remove the case and do not use it at this time.

FAQ: Frequently asked questions about battery wear

Is it possible to check battery wear without installing applications?

Yes, but the accuracy will be lower. Use the manufacturer's built-in tools (codes ##4636## or *#0228# for Samsung) or connect via ADB. These methods do not require third-party software, but may not show the actual capacity.

Why do applications show different wear?

Applications without root estimate wear indirectly (by discharge time, voltage, temperature), so the data may differ by 10-15%. The most accurate results are obtained ADB, the engineering menu or specialized utilities like 3C Battery Monitor with root access.

What to do if the phone turns off at 20-30% of the charge?

This is a sign of severe battery wear or malfunction controller. Try calibrating the battery (discharge to 0% and charge to 100% without interruption). If it doesn’t help, the battery needs to be replaced.

Is it possible to restore the battery capacity?

No, it is impossible to restore a worn-out lithium battery. All “miracle methods” (freezing, flashing the controller, special charging) are a myth. The only solution is to replace it with a new battery.

How many charging cycles can a modern battery withstand?

The average resource of lithium batteries is 500–1000 full cycles (from 0% to 100%). After this, the capacity drops to 70–80% of the original. Cheap batteries may have a lower lifespan (300–400 cycles).

If you notice that your smartphone battery is draining too quickly or is behaving unstable, do not delay diagnosis. The sooner you identify the problem, the cheaper and its solution will be safer. For most users, free applications like AccuBatteryare enough, but if you need accurate data, use ADB or the engineering menu.

Remember: a worn-out battery is not only an inconvenience, but also a risk of fire. Do not ignore signs of degradation!