The Xiaomi Mi8 was released in 2018 and is still a popular device among fans of balanced performance. However, time inexorably affects the chemical batteries, and many users face rapid discharge or sudden shutdowns of the gadget. The question of which battery is installed in this model becomes critical when planning repairs or self-maintenance.
Flagship owners often set out to extend the autonomy of the device without changing the usual form factor. Understanding the technical specifications of the battery allows you to choose a quality analog or original spare part, avoiding problems with compatibility. Next, we will discuss in detail the parameters of the regular battery, signs of wear and tear and step-by-step algorithm of actions during replacement.
Technical characteristics of the full-time battery
The Xiaomi Mi8’s power supply is based on a non-removable lithium-polymer battery, which is equipped with a 3400 mAh battery, a standard value for flagships of the period, which provides a balance between the thickness of the case and the operating time. However, the actual capacity available to the user may vary slightly depending on the calibration of the controller.
The cell voltage is industry standard 3.85 V, which corresponds to an energy capacity of about 13.11 Wh. It is important to note that the battery supports Quick Charge 4+ fast charging technology, which allows you to recover charge up to 50% in just 30 minutes using the original adapter.
⚠️ Warning: Using non-original chargers with unsupported voltage profiles can lead to overheating of the power controller and degradation of battery chemistry.
The dimensions of the battery are designed to make the most of the interior space of the housing without protruding parts. The tight layout requires accuracy when changing, because the space reserve is minimal. Any deviation in size when selecting a spare part can lead to the inability to close the back cover or damage to the plumes.
Signs of wear and need for replacement
There are a number of indirect and direct indications that a Li-Po element is exhausted, and the most obvious symptom is a sharp drop in charge as a percentage, for example, from 40% to 5% in a few minutes of active operation, and a sudden switch-off of the smartphone when there is a charge, which the display shows as sufficient.
Physical changes in the body can also indicate a problem: if the back cover has started to recede or the screen has bloated, this indicates the release of gases inside the battery, it is strictly forbidden to operate the device in this state, as this creates a risk of fire or damage to the display matrix.
- 📉 The smartphone is discharged to zero faster than for 3-4 moderate-hour.
- 🌡️ The body of the device is very hot even for simple tasks like calling or reading.
- 🔋 The charge indicator “jumps” or hangs at one percent for a long time.
- 💥 There was swelling, and the phone stopped lying flat on the table.
If before the Xiaomi Mi8 gained full charge in an hour and a half, and now this process takes 4-5 hours, then the internal resistance of the battery has increased, and it stopped taking current efficiently.
The choice of a new battery: original or analogue?
When looking for a replacement, the owner faces a dilemma: look for a rare original or choose a quality analogue. The original Xiaomi BM3E battery (model code for Mi8) has perfect compatibility and claimed cycle life. However, finding a new original part years after the model was discontinued is extremely difficult, and there is a high risk of running into the restored element.
High-quality analogues from well-known brands such as Nohon, Deji or Baseus often offer increased capacity. 3500-3600 The real difference may be small, but the chemical composition in them is fresher than in the deposited “originals».
| Parameter | Original (Xiaomi) | Quality analogue | Cheap analogue |
|---|---|---|---|
| Capacity | 3400mAh | 3400-3600 mAh | Claimed 3400, real 2000 |
| Cycle resource | 500+ cycles | 400-500 cycles | 100-200 cycles |
| Protection | Complete. | Basic | Absent. |
| Price. | Tall. | Medium | Low. |
What are charge cycles?
When buying, check for holograms and QR-Cheap copies often don't have a recharge controller, which can be dangerous.
Tools and preparation for repairs
Replacing the battery in the Xiaomi Mi8 requires accuracy and a specific set of tools. The design of the smartphone involves disassembling through heating the back cover, which is planted on glue. Without a thermophen or special heating pad, it is almost impossible to open the case without damage.
You will need a glass lifting suction cup, thin plastic mediators (scapula) and a set of screwdrivers, including a cross PH000. It is also highly recommended to have tweezers with curved ends and isopropyl alcohol on hand to dissolve old glue. Be sure to prepare a new B-7000 glue or special adhesive tapes to fix the lid.
☑️ Preparation for battery replacement
Before starting work, be sure to turn off your smartphone. Even short-term closure of the battery contacts with the train connected can disable the power controller on the motherboard, which will lead to expensive repairs.
⚠️ Warning: Never use metal objects (knife, needle) to pick under the battery or near plumes.
Step-by-step instructions for replacement
The replacement process starts with heating the back panel. Put the phone on the heating pad or gently warm the perimeter with a hairdryer for 2-3 minutes. The glue should soften, allowing the suction cup to stick and lift the edge of the glass. Insert a plastic card into the gap and slowly guide it along the perimeter, cutting the adhesive layer.
Once the lid is removed, you'll have access to the insides, and the first thing you need to do is to unscrew the screws that hold the protective plate of the charging module and the speaker, and they're usually around. 10-12 They can be different in length, so you better group them into the disassembly steps.
Carefully disconnect the battery connector with a plastic blade, then unstick two traction tongues (if they are preserved) or use a special adhesive solvent to remove the old element. Never pull the battery by force if it is glued, this can cause it to deform and ignite.
Sequence of action:
1. Heating the hull.
2 Removal of the back cover.
3. twisting of the screws of the lower plate.
4. Disabling the battery plume.
5. Removing the old battery.
Installation of new and connection.
7. Test inclusion.Install a new battery, make sure it sits tightly in the niche. Connect the plume to a characteristic click. Before final assembly and sealing of the lid, it is recommended to turn on the phone and check the charging, touchscreen and cameras. If everything works, apply a new layer of B-7000 glue to the frame and press the lid with rubber harnesses for 1-2 hours.
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Leave your phone on charge for 2-3 hours after the first installation of the new battery, even if the indicator is 100%, which will help the controller to calibrate and even out the balance of the cells.
Calibration and extension of service life
After replacing the battery, it is recommended to perform a calibration procedure, which will help the Android system correctly display the percentage of charge. To do this, completely discharge the phone before turning off, then put it on charge in the off state to 100%. After reaching full charge, hold it on the wire for about an hour.
To extend the life of the new battery in Xiaomi Mi8, you should avoid extreme temperatures. Do not leave your smartphone in the sun or in the cold. The optimal temperature range for operation and storage of lithium polymer cells is from +10 to +25 degrees Celsius.
- 🌡️ Try not to bring the charge to the 0% regularly, it is better to put on charging when 15-20%.
- 🔌 Use only certified cables and power supplies with support QC.
- 📱 Disable unused functions (GPS, Bluetooth, if you don’t need it right now.
Also worth paying attention to background processes. Some applications may not work properly after a system update and "wake up" the processor, causing increased power consumption. Check the statistics in the Settings → Battery menu and limit the background activity of voracious programs.
Is it safe to use a high-capacity battery?
Why does the phone turn off 20% of its charge?
Can I charge the Xiaomi Mi8 wirelessly after being replaced?
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A high-quality battery replacement returns the 2018 flagship to the level of autonomy of the new device, making the purchase of an expensive new smartphone optional.
Compliance with replacement technology and the choice of a proven power component will allow your Xiaomi Mi8 to last for several more years.Do not skimp on safety and quality of spare parts, as the battery is the most important and potentially dangerous element of the smartphone design.