Modern smartphones Xiaomi, Redmi and Poco are famous for excellent autonomy, but even the most capacious lithium-polymer batteries lose their original capacity over time.
When the device starts to discharge in a couple of hours or spontaneously turns off when the charge is 20%, the user is faced with the question of replacing the energy source.
The battery extraction process is a delicate procedure that requires an understanding of the design of the gadget, since most models have a non-shattered Unibody type body.
Diagnosis of the state of the battery and signs of wear
Before starting disassembly, you need to make sure that the problem lies in the physical wear of the chemical element, and not in software failures or background processes.
One of the most obvious signs of degradation is the bloating of the body, which can be seen by the edges of the display that have moved away from the frame or the deformation of the back cover.
Bloating is a critical condition that requires immediate intervention, as a damaged battery can ignite during further operation.
Another indicator is a sharp drop in voltage under load when the phone turns off, even if the indicator shows 30-40% charge.
You can check the status through an engineering menu or special applications, but visual inspection and analysis of the behavior of the device often give a more accurate picture.
If you notice that the Xiaomi phone gets very hot in the camera area even in downtime, it could also indicate an internal short circuit in the battery jar.
⚠️ Note: If the battery is very swelled and puts pressure on the display, in no case do not try to force it back or pierce a sharp object to release gases!
Tools and workplace preparation required
A specialized set of tools will be needed for a quality replacement, as conventional household appliances can damage fragile plumes or break glass.
First of all, you will need a hair dryer or a professional thermoplatform to soften the adhesive layer that holds the back panel.
Also indispensable are plastic mediators (scapula), a suction cup for lifting the lid and tweezers with a dielectric coating for working with connectors.
- 🛠️ Thermophen or heating pad for uniform heating of glue.
- 🔧 Torx screwdriver set (usually) T5 or T6) screw-hole.
- 🧤 Thin plastic mediator or guitar plastic for opening.
- 🧪 Isopropyl alcohol or special solvent of glue B-7000.
- 🧲 Magnetic mat for sorting small screws.
The workplace should be well lit and free of metal objects that may accidentally close the board contacts.
It is recommended to use an antistatic bracelet or regularly touch a grounded metal object to remove static electricity from the body.
All screws are better to lay out in order of their extraction, since in Xiaomi smartphones they can have different lengths and threads.
The process of disassembling the smartphone body
The first step is always to completely shut down the device and remove the tray. SIM-cards so as not to damage contacts during heating.
Then you need to heat the perimeter of the back cover to a temperature of 80-90 degrees Celsius, holding the hair dryer at a distance of 3-5 cm for 2-3 minutes.
Do not overheat the glass, otherwise it may burst from thermal shock, especially if the screen already has microcracks.
After heating, the suction cup is attached to the bottom of the rear panel, and a small gap is created, where a plastic mediator is carefully inserted.
Movements should be sliding along the perimeter, without sharp jerks, so as not to damage the plume of the fingerprint scanner or the main camera module.
In some models of the Redmi Note series, the fingerprint scanner is located on the back cover and is connected by a long plume running to the board, so you need to open the lid with maximum care.
When the lid is completely separated from the glue, it should be carefully placed in a safe place, it is best to put on the soft fabric with a screen down.
Next, you should unscrew all visible screws that fix the plastic protective panel that covers the motherboard and the battery.
Often, screws can be hidden under stickers or rubber plugs that need to be inspected carefully in good lighting.
Disconnecting plumes and removing the old battery
After removing the protective plate, access to the insides is opened, where the first thing to do is to disconnect the battery connector from the motherboard.
Use a plastic shoulder blade or nail to plug the connector upwards, avoiding the use of metal tools that can cause a short circuit.
Power outage is a critical step that shuts down the device and prevents accidental power surges when working with other components.
The battery itself in Xiaomi smartphones is usually fixed to double-sided scotch or special adhesive strips located at the edges of the element.
Special pulling tongues are often used for extraction, but if they are not present or they have broken, careful tweaking of the battery housing will be required.
Never squeeze the battery with your fingers too hard and do not use sharp metal objects for tampering, as puncture of the shell will cause ignition.
☑️ Safe extraction
If the battery sits very tightly, you can slightly warm the back of the body with a hairdryer to soften the glue under the power element.
In some models, such as the Xiaomi Mi series, the battery can be closed with an additional layer of graphite thermal insulation, which also requires careful removal.
After removing the old element, carefully inspect the niche for glue residues, debris, or electrolyte traces that need to be removed.
Comparison of original and compatible batteries
Choosing a new battery is key, as the market is full of cheap analogues that may not only not solve the problem, but also harm the device.
The original batteries have special protective boards and markings that meet Xiaomi quality standards.
| Characteristics | Original (OEM) | Quality copy | Cheap analogue |
|---|---|---|---|
| Capacity | Conforms to the stated | Often understated by 10-15% | Maybe 2 times less. |
| Cycle resource | 500-800 cycles | 300-400 cycles | 50-100 cycles |
| Protection | Full set of sensors | Basic protection | Absent or weak |
| Compatibility of SOEs | Complete. | Possible errors % | Frequent calibration failures |
When buying, pay attention to holograms, the quality of font printing and the availability of QR-code for verification on the official website.
Cheap copies often have a plastic case that takes away heat worse, leading to overheating and accelerated degradation.
Using non-original components can lead to calibration errors when the system shows an incorrect percentage of charge.
How to check the battery after installation?
Installation of a new element and assembly of the device
Before installing a new battery, it is necessary to clean the seat of the old glue with alcohol or a special cleaner.
On the new element, fresh strips of bilateral tape are glued to ensure reliable fixation and the absence of backlashes inside the case.
The battery fixation should be rigid, as vibrations when walking or talking can damage the connector if the element moves.
Connect the plume of the new battery to the connector on the board to the characteristic click, making sure that the contacts entered smoothly and without distortion.
Do not turn on the phone immediately, first assemble the case to check the operation of all modules in the assembled state.
Install a protective panel, twist all screws and glue the back cover, pre-degrease the ends of the body.
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Use B-7000 glue to fix the lid: it remains elastic after drying, allowing you to open the phone in the future without the risk of damage to the glass.
For better adhesion, it is recommended to press the phone with rubber harnesses or put under the press for 1-2 hours until the glue is completely dry.
After assembly, turn on the device and check if the battery is correctly determined, and if the connection area is not warming.
If the phone doesn’t turn on, it’s possible the connector isn’t fully inserted or the contact is contaminated, requiring re-disassembly.
Primary charging and calibration of the system
After a successful replacement, it is recommended to hold the first charge in the off state to 100% so that the power controller correctly counts the capacity.
Modern controllers in Xiaomi are smart, but they take time to synchronize the readings of the voltage sensors with the software part of MIUI.
In the first days of use, try not to discharge the phone to zero and do not keep it on charging longer than necessary.
⚠️ Note: Do not use fast high power charges (above normal) in the first 2-3 charging cycle of the new battery so as not to overheat the chemical composition.
If the percentage of charge jumps or the phone turns off by 15%, manual calibration via an engineering menu or third-party utilities may be required.
In some cases, resetting settings to factory helps, but this is an extreme measure that should be resorted to only with obvious software glitches.
Watch the temperature of the device in the first weeks: heating up to 40 degrees with active charging is considered normal, but not more.
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Proper calibration in the first days of use extends the life of the new battery and ensures the accuracy of the charge display in the system.