Xiaomi Redmi 8 has proven to be a reliable device with impressive autonomy, but over time, even the best battery loses its capacity. If your phone stops holding charge, turns off in the cold or the body is swollen, you need to replace the battery. Replacing the battery is a procedure that requires accuracy, understanding the design of the device and the availability of specialized tools.
Unlike older models with removable covers, modern gadgets are assembled on adhesive basis, which makes it much more difficult to access the internal components. The adhesive layer securely fixes the rear panel, preventing dust and moisture from entering, but it becomes the main obstacle during repairs. Incorrect opening of the case can damage the plumes, break the glass or, worst of all, damage to the battery itself.
In this article, we will take a closer look at the process of dismantling an old power source and installing a new power source, learn what tools will be required to safely run the work, how to turn off the plumes, and what precautions are critical to keeping your Redmi 8 running. Remember that self-repair always comes with risks, so follow the instructions Step-by-step.
Tools and workplace preparation required
Before any electronic manipulation begins, you need to have a comfortable and safe workspace, you need a table with good lighting to see the small details and screws, the absence of statics and foreign objects is the key to successful repairs, it is important to prepare all tools in advance so that you do not interrupt the work process when the internal components of the device are open.
To disassemble the Xiaomi Redmi 8, you will need the following set of tools:
- 🔧 Hair dryer or heating pad for heating the adhesive layer around the perimeter of the housing.
- 💳 Plastic card or mediator for tidy detachment of the cover.
- 🪛 Sets of screwdrivers (cross Phillips #00 and flat).
- 🧲 Magnetic mat or container for sorting screws of different sizes.
- 🧤 Tweezers with dielectric tips for working with small details.
⚠️ Warning: Never use metal blades or knives to open the case from the screen or back unless you are sure of the depth of the immersion.The metal can damage the display plumes or puncturing the lithium polymer battery, which will cause a fire.
Pay special attention to the preparation of the battery. If you plan to remove the old battery for recycling, make sure that it does not have external damage. In case of bloating, you need to work with it extremely carefully, avoiding pressure on the body. Lithium polymer cells are sensitive to punctures, so tweezers should only be used for special tongues or edges of the board, but not for the soft shell itself.
The process of heating and removing the back cover
The most time-consuming step is to separate the back glass panel from the metal frame. The B-7000 factory glue or its analogues become very hard when drying. To soften the adhesive, you need to warm the perimeter of the device evenly. Use the dryer at medium temperature, driving a jet of air along the faces for 2-3 minutes. Do not hold the hair dryer at one point for too long, so as not to overheat the OLED or LCD matrix.
After heating, insert a plastic mediator into the joint between the frame and the glass at the bottom of the smartphone, where the speaker is usually located. Carefully steer the instrument along the side faces, listening to the characteristic sound of the adhesive being torn. If you feel strong resistance, warm up the area again with a hairdryer. The rush at this stage often leads to cracks on the back cover, so act slowly and methodically.
When the mediator passes through the perimeter, the lid should be lifted up easily. But don't open it like a book! There may be thin plumes inside the device that connect the main board to the additional modules. In Redmi 8, the main connections are at the top, but it's better to be safe and not make any sudden movements until you make sure that there are no stretched wires.
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Use a glass suction cup to create an initial gap after heating, which will make it easier to insert a plastic mediator and reduce the risk of crushing the glass with your fingers.
Disabling plumes and dismantling protective screens
Once you successfully remove the back cover, you'll have access to the insides of your smartphone. The first thing you need to do is turn off the device. Find the battery connector on the motherboard and gently unplug it. Use a plastic blade or nail to do this by putting the connector up, and only after the battery is turned off can you safely work with other components.
Next, you take out the metal plate that covers the main connectors and mounts, and it's fixed by several screws of different sizes. Remember or draw the location of the screws, because their length may vary. A short screw screw screw screwed into the hole for the long one can penetrate the board through, causing a short circuit.
Under the protective plate are the plumes of the display, touchscreen and camera modules. They also need to be turned off before fully removing the motherboard if you plan to deep clean. However, for a simple battery replacement in the Xiaomi Redmi 8, it is often enough to simply bend the board or remove the top plastic speaker frame, which is also glued. Carefully warm up the top of the case and remove the plastic speaker plug to access the bottom of the battery.
- 🔌 Turn off the charging module plume located at the bottom.
- 📸 Be careful with camera plumes, they are very thin and easily break.
- 🔋 Check the condition of the battery connector for oxidation or sodium.
☑️ Ready to retrieve the battery
Removal of the battery and cleaning of the seat
The battery in Redmi 8 is glued to a metal frame or plastic base on double-sided tape. The adhesion strength here is less than that of the back cover, but still significant. Use a plastic card or a special tool with a fishing line to extract it. Carefully enter the tool under the battery from the bottom end, where there is usually a small gap.
Move the tool or the fishing line back and forth, gradually cutting off the adhesive layer. Don't use force to not bend or pierce the battery body. If the battery is swelled, it will take up more space and press the components, so you need to remove it with double caution. In some cases, it helps to lightly heat the lower part of the body with a hairdryer, but the temperature should not exceed 60-70 degrees.
Once the old battery is removed, you need to thoroughly clean the seat of glue residues. Use isopropyl alcohol and a soft wipe. The surface must be perfectly smooth and clean so that the new battery will lie flat and tight. Remains of the old glue can create voids, which will lead to uneven pressure distribution and possible damage to the new battery during assembly.
⚠️ Warning: If you smell chemicals or see sparks when you're extracting, stop working immediately, take the device outdoors and dispose of it in a special lithium battery container.
Comparison of characteristics of the original and analogues
When choosing a new battery, it is important to pay attention not only to the manufacturer’s brand, but also to technical parameters. The market is filled with many copies, which may differ in real capacity and quality of materials. Below is a table to compare the main characteristics that you should focus on when buying components for the Xiaomi Redmi 8.
| Parameter | Original (OEM) | Quality analogue | Cheap copy |
|---|---|---|---|
| Capacity (claimed) | 5,000 mAh | 4800-5000 mic | 3500-4000 mic |
| Tension. | 3.85V - 4.4V | 3.85V - 4.4V | Unstable. |
| Protective fees | Got it (BMS) | There's (simplified) | Often absent |
| Cycle resource | 800+ cycles | 500-600 cycles | 200-300 cycles |
| Guarantee | Official. | From the store. | No. |
Original batteries have a logo marking MI And the exact technical data, printed indelibly, on cheap copies, the font can be blurry, and the capacity can be overstated in the description, but not in reality. BMS-controllers in cheap batteries can lead to improper display of percentages of charge or sudden switching off of the smartphone.
How to check the battery multimeter?
Device assembly and initial start
The new battery is installed in reverse disassembly order. First, stick the new battery onto special adhesive strips (usually complete with a new part), or apply a thin layer of B-7000 glue around the perimeter. Connect the battery plume to the motherboard before you click. Make sure the connector is flat and not skewed.
Before the final sealing of the case, it is recommended to perform a test run. Connect the charger and check if the charger is going and whether the screen is reacting. If everything is working correctly, you can proceed to the final assembly. Apply a new layer of glue around the perimeter of the back cover, combine all the holes and tightly press the panel. Lock the device with rubber harnesses for 15-20 minutes to polymerize the glue.
Calibrate the battery after assembly, completely discharge the smartphone before it turns off, then charge it to 100% without interrupting the process, which will help the power controller to correctly display the charge level. Calibration is especially important if you notice that interest rates "jump" or the phone turns off at 15-20% charge.
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High-quality assembly and use of original adhesives ensure the preservation of moisture protection (at the basic level) and prevent backlash of the case in the future.