Xiaomi Mi 8 — flagship 2018 It's still popular with users today because of its powerful hardware and affordable price in the secondary market. 4-5 In the past, even the best battery has lost 30-40% It's a capacity that causes quick discharge, spontaneous reboots and charging problems. 8 Became “hold” for only a few hours, and in the settings appears a notification “Battery requires replacement”, it’s time to act.
In this article you will find step-by-step instructions for replacing the battery with Xiaomi Mi 8 (including versions of the Mi 8 SE mi 8 Pro, a list of tools you need, tips for choosing a new battery, and answers to frequent questions, and we’ll also tell you how to avoid common errors that can damage the board or display. With the right approach, the procedure will take no more. 30-40 minute.
Before you start, check if the battery is really a problem. Go to Settings → Battery → Battery status (by MIUI 12 And the newer path may be different. If the capacity has fallen lower. 80% from the original, and the smartphone is turned off when 20-30% Otherwise (for example, in case of software failures) resetting or flashing can help.
1. Which battery to choose for Xiaomi Mi 8: original vs analogues
The first and most important step is to buy a quality battery, which not only affects the life of the smartphone, but also its safety. MDY11-EM (3400 mAh, 3.85 V. But it's almost impossible to find them on sale today, because the company has long since withdrawn the model from production?
Criteria for quality battery:
- 🔋 Capacity: at least 3300-3500 mAh (indicated on the sticker) Batteries with declared "4,000 mAh" and above are fake.
- 🏭 Manufacturer: proven brands - Patona, Baseus, Remax, ZMI (Xiaomi subsidiary: Avoid no-name Chinese batteries without certificates.
- 📦 Set: the set should be two protective films (for the upper and lower parts) and adhesive tape for fixation.
- 🔍 Appearance: the original battery has no scuffs, corrosion on the contacts, and the font on the sticker is clear (without blurring).
The average price of a quality battery for the Mi 8 is 1500-2500 rubles (2026). Too cheap options (below 1000) ₽) Most often they are defective or with an understated real capacity. Before buying, check the reviews on the site (for example, on AliExpress or Yandex Market) and ask the seller for a photo of the battery with a capacity tester.
⚠️ Do not buy batteries that say "For Mi". 8/Mi 9» — They're incompatible connectors, and they can damage the charging controller. 8 mi 9 battery-box!
| Manufacturer | Model battery model | Capacity | Average price | Features |
|---|---|---|---|---|
| Xiaomi (original) | MDY11-EM | 3400 mAh | 2500–3500 ₽ | Hard to access, high reliability |
| Patona | PAT-MI8-3400 | 3400 mAh | 1800–2200 ₽ | Good reviews, full compatibility |
| Baseus | BS-MI8-3350 | 3350 mAh | 1600–2000 ₽ | Budget option, capacity slightly lower |
| ZMI | ZB-MI8 | 3400 mAh | 2000–2400 ₽ | Xiaomi subsidiary brand, high quality |
2. Replacement tools: what will be needed
To replace the battery on the Xiaomi Mi 8, you will need a minimum set of tools, most of which can be bought at electronics stores (such as the Chip and Deep) or ordered on AliExpress.
- 🔧 Plastic shoulder blades (mediators) — 2-3 Metals don't work, you scratch the frame.
- 🔨 Screwdriver. T3 and T5 (For the screws of the back cover and the plumes, it is better to use a magnetic one so that the cogs do not get lost.
- 🔥 Hair dryer or thermo-air station - for softening the glue (temperature) 60–80°C. You can replace with hot water in the bag (attached to the back cover on the 2-3 minute).
- 🧲 Suction cup - helps to lid after heating. You can use a glass suction cup from Xiaomi.
- 📏 Tweezers - for careful disconnection of plumes.
- 🧴 Isopropyl alcohol (90%+) — To clean up glue residues. Don't use acetone!
- 🔋 New battery with proven capacity and protective films.
- 🎯 Double-sided tape or glue B-7000 — for battery fixation (if there is no ribbon in the kit).
If you do not have experience disassembling smartphones, we recommend you to purchase a special repair kit (costs about 500-800). ₽). It already includes all the necessary tools. Also prepare the workplace: a table with good lighting, an antistatic mat (or at least dry fabric) and a cog container (so as not to lose your cogs).
⚠️ Warning: Do not use a knife or metal objects to lid - this will lead to irreversible scratches on the aluminum frame and can damage the plumes. Plastic blades cost pennies, but will preserve the appearance of the phone.
☑️ Preparation for battery replacement
3. Step-by-step instructions: how to disassemble Xiaomi Mi 8 and replace the battery
Now, to the most important step, the dismantling of the smartphone. Follow the instructions carefully so as not to damage the plumes or the board. If you have never disassembled the Xiaomi Mi 8, watch the video guide (link at the end of the article) - this will help visualize the process.
Step 1. Turn off the phone and remove the back cover
- Turn off the Mi 8 completely (press the power button and select “Switch off”).
- Heat the back cover with a hair dryer (keep at a distance of 5-7 cm, temperature 60-80)°C) for 2-3 minutes: the glue will become softer and the lid will be removed more easily.
- Suction the lid near the connector USB-C. Pull it up carefully - there should be a gap.
- Put a plastic blade in the gap and slowly lead it around the perimeter, separating the lid. Be careful at the camera and the buttons - there are plumes!
Step 2. Disconnect the plumes and battery
- Unscrew 10 screws (T3) Fold them in a container so you don't confuse them.
- Carefully tuck in and unplug the plumes: 📱 Battery plume (black connector near the bottom of the board). 📸 Camera plumes and fingerprint scanner (upper part). 🔊 Dynamics plume (if disturbing).
black-ribbon
Step 3: Install a new battery
- Remove the old battery and clean the installation site of glue residues with isopropyl alcohol.
- Stick a new battery: If you have adhesive tape in the kit, remove the protective layer and press the battery. If you don't have tape, apply a thin layer of glue. B-7000 perimeter and centre.
Connect the new battery plume to the circuit board connector, make sure the contacts match!
Secure the battery with protective films (they come with a set).
Step 4. Get your phone together.
- Connect all the plumes back (in the same sequence as disconnected).
- Set the middle frame and twist the screws (do not pull!).
- Press the back cover, starting at the bottom (near the bottom). USB-C). If the lid does not sit tightly, warm it up with a hair dryer again.
- Turn on your phone and check: 🔋 Charging (plug the cable – the battery icon should appear). 📸 The operation of the camera and fingerprint scanner. 🔊 Sound in dynamics.
1) Is the battery plume connected (sometimes it falls out during assembly).
(2) Are the contacts closed on the board (check for foreign objects).
3) Whether the back cover is properly installed (if the proximity sensor is closed, the phone may not respond to the power button).-->
4.Typical battery replacement errors and how to avoid them
Even with careful disassembly, you can make mistakes that will cause your phone to fail, and here are the most common problems and ways to prevent them:
- 🔌 Damage to the battery plume. When you disconnect the connector, don't pull the wires, just take a black plastic tongue. If the plume is off, you can solder it, but it takes experience.
- 🔥 If you heat the board too long, you can melt the elements on the motherboard. Keep the hair dryer at a distance and don't direct the air flow to one place for longer than 10 seconds.
- 🧲 Loss of cogs. Mi 8 screws of different lengths. If you mix them up, you can damage the board. Use a magnetic substrate or a container of cells.
- 🔋 Incorrect battery installation. If the battery is glued to a curve, it may press on the plumes or board.
- 💧 Liquid intake: Isopropyl alcohol must dry completely before assembly. Do not use wet wipes to clean.
If after replacing the battery, the phone began to discharge quickly, check:
- Is the battery plume connected to the end (sometimes it does not reach 1 mm).
- Has the new battery swelled (this can be seen from the bulge of the back cover).
- Are your energy saving settings broken (go to Settings) → Battery → Modes and select “Performance»).
⚠️ Note: If after the battery change Xiaomi Mi 8 does not turn on, but when you connect the charging icon appears battery — the problem in the plume of the display or board. Do not try to turn on the phone repeatedly: this can lead to a short circuit.
What to do if the new battery does not hold the charge?
5. How to Calibrate a New Battery on Xiaomi Mi 8
After the battery is replaced, it is recommended that calibration be performed to help the system correctly determine the capacity and prolong the battery life, which takes about 4-5 hours, but you only need to do it once.
Step-by-step calibration:
- Charge your phone to 100% (use Xiaomi’s original 18W adapter).
- Turn off charging and let your phone work for 2-3 hours (you can play games or watch videos) until the charge drops to 0% and the phone turns off.
- Don't turn the phone on right away! Wait 10-15 minutes, then plug in the charger and wait 100 percent.
- Repeat the discharge / charge cycle 2 more times.
After calibration, check the battery status in Settings → Battery → Battery status: Capacity should be displayed close to nominal (e.g. 3300-3400 mAh). If the value is greatly underestimated (e.g. 2500 mAh), problems with the charging controller may occur.
💡
Calibration of the battery should be done only after full replacement, if done more often, the battery life will be reduced due to unnecessary charging / discharging cycles.
6. Alternative methods: replacement of the battery in the service
If you are unsure of your abilities or are afraid of damaging your phone, you should contact the service center.The cost of replacing the battery with the Xiaomi Mi 8 in 2026:
- 🏠 Official Xiaomi service: 3000-4500 ₽ (battery cost warranty 6 months.
How to choose a reliable service?
- 📌 Check reviews on Yandex Maps or 2GIS (pay attention to the latest reviews over the past 6 months).
- 🔍 Ask if you have a work warranty and battery (at least 3 months).
- 💬 Check if they use original or certified batteries (ask for a photo before installation).
- ⏱ Execution time: in most services, the replacement is done in 1-2 hours.
If you decide to give the phone to the service, be sure to:
- Make a backup copy of the data (in case of resetting).
- Remove the pattern lock or fingerprint (the master may ask you to enter the password).
- Check the phone after repair: charging, camera, speaker, sensors.
7. Frequent questions about replacing the battery with Xiaomi Mi 8
❓ Can I replace the battery with the Mi 8 without disassembly (via the phone) USB)?
❓ How long will the new battery last?
❓ The phone doesn't turn on after the battery is replaced. What do you do?
❓ Can I put a battery of higher capacity (for example, 4000 mAh)?
❓ Do I need to glue the protective glass after replacing the battery?
8. Video instructions and additional materials
For clarity, we recommend watching the video guide for replacing the battery with Xiaomi Mi 8:
🎥 Video: Replacement of the Xiaomi Mi 8 battery (Step-by-step with comments)
If you have any questions or are faced with an unusual situation (for example, the phone does not turn on after replacing), contact our forum or leave a comment below.
Also useful materials on the topic:
- 📄 Technical characteristics of Xiaomi Mi 8
- 🔧 Full disassembly of Xiaomi Mi 8 (photo report)
- 🔋 How to extend the life of the smartphone battery