Xiaomi Battery Replacement: A Complete Guide from Battery Choice to Assembly

Replacing the battery on Xiaomi smartphones is a challenge that every device owner over the age of 2-3 will face sooner or later. Even the best quality lithium polymer batteries degrade: capacity drops by 20-30% after 500 charging cycles, and the phone starts to run out in a few hours. If your Redmi Note 10 or POCO X3 suddenly turns off at 30% charge or heats up during charging, these are sure signs that the battery needs to be replaced.

In this article, we will look at the whole process from A to Z: how to choose the original battery (and not run into a fake), what tools you will need to disassemble, how to safely disconnect the plumes and not damage the motherboard. We will separately focus on the nuances for popular models — from Mi 11 to Redmi 9A — where the location of the glue and mounts may differ, and at the end we will give a checklist to check the health after replacement.

Should you change the battery yourself? If you have experience with small electronics and patience, yes. The service center will charge you between 1,500 and 3,000 rubles (plus the cost of the battery itself), whereas a self-replacement will cost 2-3 times less, and the main thing is to follow the instructions and take your time.

Signs that it is time to change the battery

Sometimes the problem is the background software, a faulty charger, or a damaged USB-C connector, but there are symptoms that directly indicate battery degradation:

• 🔋 The phone turns off at 20-40% charge, although it used to run to 5-10%, due to incorrect calibration of the power controller due to wear and tear of the cells.
• 🔥 The case heats up even when it's lightly loaded (like when you call or watch a video), and older batteries have increased internal resistance, which causes them to overheat.
• ⚡ Charging is snatching, rapidly gaining interest, then "hangs" at the same level, which is a sign of damaged contacts or battery bloating.
• 📉 Battery life has been reduced by 2-3 times compared to the new device (e.g., instead of 8 screen hours, just 3-4).

To diagnose the problem accurately, check the battery status through an engineering menu or apps like AccuBattery (available on Google Play). If the capacity has dropped below 70-75% of the factory capacity, the battery must be replaced. For Xiaomi models with removable batteries (such as the Redmi 4X), the process is simplified, but most modern smartphones have a glue case, and you will need a complete disassembly.

⚠️ Warning: If the battery is swelling (the phone body is convex, the screen is moving away from the frame), immediately turn off the device and do not try to charge it. The billowing battery may ignite or explode when mechanically exposed.

Which battery to choose: original vs analogues

The battery quality is not only the life of the phone, but also the safety of the phone, and cheap fakes often lack protection from overheating and can cause fires.

Xiaomi’s official batteries can be found on AliExpress (sellers with a rating above 98% and reviews of product inspection), in branded service centers or on sites like Beru/Ozon (look for sellers with a mark “Official Partner”).

• 🔍 Article – Must be the same as the original (for example, for the Redmi Note 8 Pro it is BH41 or BH42).
• 📦 Package – The original battery has a hologram, a barcode and the inscription Made in China for Xiaomi.
• 🔧 Contacts must be clean, without oxidation, with uniform soldering.
• 📏 Thickness – counterfeits are often thinner than the original by 0.5-1 mm.

For models with fast charging support (Mi 10T, POCO F3), it is important that the new battery has the same current marking (e.g. 6.5A or 9A).

Battery replacement tools

Without the right tools, it’s almost impossible to disassemble Xiaomi without damage.

• 🔧 Screwdrivers: cross PH00 (for most screws), flat 1.5 mm (for lid tweaking), five-point Security Torx T3/T5 (for some models, for example, Mi 11).
• 🧲 Magnetic mat or screw tray – so as not to lose small details.
• 🔥 Hair dryer or thermo-air station - for softening the glue (temperature) 60-80°C).
• 📱 Plastic mediators/blades—to separate the cover and the battery.
• 🛠️ Suction - helps to tamper with the display (relevant for models with glued screen, for example, Redmi Note 9 Pro).
• 🧴 Isopropyl alcohol (90%+) — glue-residue.
• 🔌 Tweezers for working with plumes.

If you’re replacing the battery for the first time, we recommend buying a smartphone disassembly kit (costs around 500-800 ₽ on AliExpress) that usually includes all the necessary tools, including a device to remove the display.

💡

Before disassembly, take a picture of the location of screws and plumes at each stage - this will greatly facilitate reverse assembly.

For models with a waterproof body (Mi 10, Mi 11), you will need an additional sealant (such as LOCTITE 577) to restore protection after replacement.

Step-by-step instructions for replacing the battery

The disassembly process may vary slightly depending on the model, but the overall scheme is the same. Consider the universal algorithm using the example of the Redmi Note 10 Pro (similar to most Xiaomi 2019-2023).

Turn off the phone and remove it. SIM-map|Make a backup copy of the data|Charge the phone before 30-50% (to avoid short circuit)|Prepare a workplace with good lighting|Wear an antistatic bracelet (optional)-->

Step 1: Removing the back cover

1. Heat the hair dryer edge of the back cover (30-40 seconds on each side) at a temperature of 70-80 ° C. The glue will become softer, and the cover will separate more easily.

2. Insert a plastic mediator into the gap between the lid and the body (start at the bottom edge where the USB-C connector is). Carefully drive the mediator around the perimeter, separating the lid. Be careful - there may be plumes under the lid (for example, the POCO X3 NFC has an NFC antenna there).

3. If the lid doesn't respond, reheat the problem area. Don't force it, you can break the latches!

Step 2: Disconnect the plumes and remove the battery

1 Unscrew all the screws that fix the metal plate above the battery (usually 6-8 pieces).

2. Gently disconnect the battery connector with a plastic blade. Don't pull the wires! Better put the connector on the side.

3. heat the battery with a hairdryer (not higher than 60°C!) for 1-2 minutes. Tap it from any corner with a plastic blade and slowly pull up. If the battery is glued heavily, use a thread or a special pull-tab (included in some remakes).

Step 3: Installation of a new battery

1. Remove the remnants of old glue from the case (you can use alcohol and a lilac-free wipe).

2. Stick a new battery. It's usually double-sided tape -- remove the protective film gradually, pressing the battery from the center to the edges. If there's no tape, use 3M VHB or similar glue.

3. Connect the battery connector to the motherboard. Make sure the contacts are clean (wipe with alcohol if necessary).

4. Secure the metal plate and twist the screws (do not pull!).

Step 4: Assembly of the phone

1. Connect all the plumes (display, cameras, buttons) to make sure they sit tight but are not skewed.

2. Stick the back cover. For moisture-proof models (Mi 11, Redmi K40), apply a new perimeter sealant.

3. Twirl the screws of the lid (usually 10-12 pieces). Keep track of the length - in some models, screws of different lengths!

💡

After replacing the battery, be sure to calibrate: completely discharge the phone before turning off, then charge to 100% without interruptions. Repeat the process 2-3 times.

Nuances for popular Xiaomi models

Xiaomi’s smartphone design is constantly changing, and some models have their own “chips” to consider when replacing the battery.

For the POCO F3 and Redmi K40, note the extra screw under the tray for the SIM- card - it's easy to miss when disassembling. In the Mi 11 Lite, the battery is located under a metal plate with many screws - don't lose any!

⚠️ Warning: In wireless charging models (Mi 10, Mi 11), a coil is located under the battery. When installing a new battery, make sure it is compatible with this feature (it must have a Wireless Charging Supported tag).

What to do after replacing the battery

Successful battery replacement is only half the battle, and in order for a new battery to last, you need to run it right and monitor the condition of the phone.

• 🔄 Calibration: As mentioned earlier, execute 2-3 a full discharge/charging cycle, which will help the power controller accurately determine the capacity.
• 📊 AccuBattery check: install the application and compare the actual capacity to the declared capacity. Acceptable error is up to 5%.
• 🔌 Charger: Use an original adapter or certified analogue (like Baseus or Anker). Cheap charging speeds up battery degradation.
• 🌡️ Temperature control: Avoid overheating (do not play heavy games while charging) and hypothermia (do not leave your phone in the cold).

If the phone is not switched on after replacement:

1. Check if the battery connector is connected to the motherboard.
2. Make sure all plumes sit tight (especially the display and power buttons).
3. Connect your phone to charge for 10-15 minutes – sometimes the new battery is discharged to zero.
4. If nothing helps, the motherboard may be damaged (for example, when short circuit).

💡

If the battery is too fast to discharge after replacement, check the background processes in Settings → Battery. Sometimes it is not the hardware that is to blame, but the software (for example, unoptimized applications or viruses).

Top-5 errors when replacing the battery

Even the most experienced craftsmen sometimes make mistakes that cause the phone to break down.

1. Using metal tools to separate the battery, one careless move, and you puncture the battery, which can cause fire. Always use plastic blades!
2. Overheating of the battery with a hair dryer. Temperatures above 80°C damage the adhesive and can deform the body. Optimal range is 60-70°C.
3. Incorrectly installed plumes. For example, in Redmi Note 9, the fingerprint scanner plume is easily confused with the power button plume. Always check the photos taken before disassembly.
4. Ignoring waterproofing. If you don't replace the sealant in the Mi 10 or POCO F2 Pro, the phone will lose water protection, even if everything looks normal on the outside.
5. Buying a battery without checking. Counterfeiting often has an understated capacity (for example, instead of 5020 mAh, a real 4000 mAh). Always test a new battery with a multimeter or through AccuBattery.

Another common problem is that the phone doesn't see the new battery.

• Bad contact of the connector (check if it is bent).
• Incompatible battery (for example, took the battery from the Redmi Note 8 Note 8 Pro – they look similar, but have different controllers).
• Resetting the power controller settings (sometimes helps reset via Fastboot command fastboot erase config).

FAQ: Frequent questions about replacing the battery with Xiaomi