Xiaomi Redmi 5, released in 2017, has proven to be a reliable device with a metal body and good performance for its time. However, lithium-polymer batteries have a limited resource of charge-discharge cycles, and after several years of active use, owners face rapid discharge, spontaneous shutdowns in the cold or battery bloating. Replacing the battery is the most effective way to return the device to its former autonomy, avoiding buying a new gadget.
The recovery process requires accuracy and understanding of the design of the device, as the Redmi 5 has not the simplest disassembly scheme compared to modern models with removable covers. You will have to work with adhesive joints, plumes and small screws, so rush is unacceptable. Properly executed procedure will extend the life of the device for another 2-3 years of active use.
In this guide, we will discuss all the steps in detail: from the preparation of the workplace and tools to the final test of the tightness and operability of the system, and pay special attention to the nuances of unsticking the display and working with connectors, the damage of which can lead to more serious consequences than just a discharged phone.
Diagnosis of the condition and selection of components
Before you start disassembling, you need to make sure that the problem lies in the physical wear of the chemical current source. Software failures or background processes sometimes create the illusion of rapid discharge. Check the energy consumption statistics in the Settings → Battery menu and pay attention to the behavior of the indicator: if the phone turns off at 15-20% charge or the percentage of charge jumps sharply (for example, from 60% immediately to 10%), this is a sure sign of cell degradation.
The choice of a new battery is a critical stage.The market is crowded with cheap copies that can not only quickly lose capacity, but also damage the motherboard's power controller.The original battery for the Redmi 5 is labeled BM3B 3300mAh, and pay attention to hologram availability, font printing quality and, ideally, availability. QR-code for verification on the official website of the manufacturer.
⚠️ Warning: Avoid buying batteries without protective film on contacts and with damaged packaging. Using poor-quality batteries can cause the device to overheat and even catch fire.
If you're not sure about your ability or you can't find a trusted supplier, you'd better go to an authorized service. However, self-replacement with the original part saves a lot of money. It's also important to check the status of the plume connecting the bottom to the main one, because if you disassemble it carelessly, it's easy to damage it.
- 🔍 Check the current capacity through an engineering menu or third-party utilities like AccuBattery.
- 📦 Make sure that the new battery has a voltage. 3.85V (standard).
- 🏷️ Look for a battery production date: the fresher, the better (optimum up to 6 months).
- 🛡️ Xiaomi’s original batteries often have a protective sticker with a changing color when heated.
It is worth noting that calibrating the battery after installing a new element is mandatory for the correct display of the percentage of charge by the Android system. Without this procedure, the phone can show incorrect data, which will lead to inconvenience in operation.
Tools and workplace preparation required
Xiaomi Redmi 5
The main tool will be the heating element. The glue that holds the display to the frame is very strong at room temperature. Using a hair dryer (construction or household at minimum power) or a special heating pad will soften the adhesive and open the case without cracks in the glass. Don't try to poke the screen cold - the result will be disastrous.
☑️ Checklist of instruments
Also, prepare the screw tank, as the smartphone design uses fasteners of different lengths, confusing them, you can break the motherboard or damage the thread in the plastic pillars of the case. Organize the workspace: the table should be clean, well-lit and not conduct electricity (wooden or covered with antistatic mat).
- 🌡️ Hair dryer for heating glue around the perimeter of the body.
- 🔧 Screwdrivers: Phillips #00 and Torx cross T5 charge-pen.
- 🧲 Magnetic mat or organizer for sorting screws.
- 🧹 Isopropyl alcohol and lilac-free wipes for cleaning glue.
Remember to turn off the device before starting work. Even when switched off, residual current can pass through the circuits, but turning off the power minimizes the risks of short circuits when disconnecting the connectors.
Disassembly process: Display dismantling
The most important step is to separate the display module from the metal frame. Turn on heating and evenly warm the face of the smartphone for 2-3 minutes. The temperature should not exceed 80-90 degrees Celsius, so as not to damage the matrix or adhesive layer of the oleophobic coating. Check the heating can be with the back of the palm: if the hand is hot, but tolerant, the temperature is sufficient.
After warming up, place the suction cup at the bottom of the screen (above the Home button if there is one, or just below the center) and pull up slightly to create a gap. Insert a plastic mediator into the resulting gap carefully. Driving the instrument along the perimeter, cutting the adhesive layer. Movements must be sliding, without much effort upwards, so as not to push through the glass.
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To facilitate disassembly, you can introduce a little isopropyl alcohol into the gap between the glass and the frame - it will dissolve the glue and make the process safer.
Be careful in the corners and in the plume area. Don't remove the mediator completely until you've passed the entire circuit. If you feel strong resistance, warm up the problem area again. Trying to open the case by force is guaranteed to lead to cracks in the glass display.
⚠️ Warning: Do not use metal blades or knives to open the case. Metal can damage the touch scanner or close contacts under the frame, which will disable the smartphone.
When the module is separated around the perimeter, don't make any sudden movements. The display is connected to the motherboard with a loop that is limited in length, and put the phone up on the soft surface with the screen and proceed to the next step.
Disconnecting plumes and removing the old battery
When you successfully lift the display, you'll see a metal screen covering the main components, which is secured by a few screws that you need to unscrew, and underneath the screen are the display connectors, the touchscreen, and most importantly, the main board plume, and the first thing you need to do is turn off the battery to shut down the system.
Find the battery connector (usually closer to the bottom edge of the board) and gently snap the connector with a plastic blade. The movement should be straight up, without distortion. Only after the power is turned off can the display and touchscreen plumes be disconnected. It's the golden rule of electronics repair: the power is turned off first, which prevents power surges.
Now you can take the display module completely off and put it back up to a safe place with a screen, and you can access the battery, which in Redmi 5 is glued to the body with two strips of double-sided tape, you need to retrieve it, you need to heat it up again, warm up the back of the case (metal back) in the battery area.
- 🔋 Disconnect the battery connector first, before removing other plumes.
- 🌡️ Heat the case from the back to soften the glue under the battery.
- 🏺 Use a plastic card or spatula to tamper with the battery.
- 🧵 If you have special tongues for pulling – pull them slowly.
If the tongues are not there, gently shovel the battery from one edge, gradually moving inwards. Do not try to pull the element out with a jerk - this can damage the lithium-polymer cell shell. Also be extremely careful with the plume going to the bottom board (with the charging connector), as it often passes under the battery or next to it.
What to do if the battery is blown?
Installation of a new battery and assembly
Before installing a new battery, you need to thoroughly clean the seat of the residue of old glue. Use isopropyl alcohol and a plastic card. The surface should be smooth and clean, so that the new bilateral tape (usually complete with the battery) lays perfectly and provides reliable fixation.
Stick new strips of tape onto the case or on the battery itself (according to the instructions for the specific spare part). Place the battery in a niche, making sure it lies flat and does not protrude beyond the edges. Connect the connector to the motherboard before the characteristic click. Make sure the locks fall into place.
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It is critical to check that the plumes are not twisted or clamped with the body, otherwise they can get damaged or move away when assembled.
Now you can test the system to full build. Without screwing the screen, press the power button. If the phone starts, shows the image and reacts to touch, you're on the right track. Check the charging: plug the cable in and make sure the charge indicator is active.
If everything works, get to the final assembly. Put the plumes neatly along the guide channels. Set a metal shield and twist all the screws. Pay special attention to the screws in the corners - they can be of different lengths. Then apply a new adhesive B-7000 or use a ready-made adhesive frame around the perimeter of the body to fix the display.
| Phase | Action. | Important nuance |
|---|---|---|
| 1 | Cleaning the hull | Remove all old glue with alcohol |
| 2 | Fixing the ACB | Use a new bilateral scotch |
| 3 | Connection | A clear click of the connector is heard. |
| 4 | Test | Checking the inclusion before gluing |
| 5 | Hermetization | Applying B-7000 glue along the circuit |
After applying the glue, press the screen tightly around the perimeter and lock the smartphone with money bands for 30-60 minutes until the adhesive is completely dry, which will provide the necessary tightness and protection from dust.
Primary calibration and result verification
After the glue is assembled and dryed, turn on the smartphone. The first charge-discharge cycles will determine how the system will display energy levels. Android may not correctly show percentages immediately after replacement, so it is recommended to conduct a calibration procedure.
Discharge the phone until it is completely turned off (0%). Then, when it is off, charge it to 100%. After reaching full charge, do not turn off the cable for another 1-2 hours. This will allow the power controller to write down new values of capacity. Repeat the cycle 2-3 times for best results.
Also, pay attention to the touchscreen and display, there should be no dead zones, color distortions or flickering, if the battery is warming to a idle after replacing, or the phone is quickly discharged, you may have got a defective instance or a poorly connected connector.
- ⚡ Take it. 2-3 Full charge cycle for calibration of the controller.
- 🌡️ Keep an eye on the temperature of the body during the first hours of work.
- 📱 Check the operation of all sensors (approach, lighting).
- 📶 Make sure that the communication modules (Wi-Fi) work consistently, GSM).
A successful battery replacement will not only restore comfort of use, but also protect the device from the risks associated with the operation of an old, degraded battery.