Xiaomi Redmi 4X, released in 2017, is still popular thanks to its reliability and metal body. However, time is inexorable: Lithium polymer batteries lose capacity after 500-800 charging cycles, leading to rapid discharge and unexpected phone shutdowns. If your gadget stopped holding a charge for at least half a day or shuts down at 20-30% charge, it’s probably time to think about replacing the power source. Self-replacement battery is a real way to save money and extend the life of your favorite device for another year or two.
The process of replacing the battery in the Redmi 4X is technically simple, but requires care, since the model has an all-metal body and a hidden screw under the sticker. You do not need complex soldering stations, a basic set of tools and patience. In this article, we will discuss in detail each step from preparing the workplace to calibrating the new battery.
It's important to understand that the quality of a new battery is crucial. The market is full of cheap copies that can swell in a couple of months, we'll tell you how to distinguish the original from the fake, and what labels to look for when you buy it, and you'll learn about the nuances of working with adhesive bases and connecting the connector correctly, which is critical for safe operation of a smartphone.
Diagnostics and selection of a new battery
Before you start disassembling, you need to make sure that the problem lies in the physical wear of the battery, and not in software failures or malfunction of the power controller. On Xiaomi smartphones there is a hidden engineering menu that allows you to check the current state of the battery. To do this, in the application "Phone" dial the combination ##6485##. In the list of parameters you are interested in items MB_06 (the state of battery health; and MF_05 (charge-cycle).
If the value MB_06 It's shown as "Good," but the phone is acting strangely, and it may require calibration or firmware, but if the status changes to "Bad" or "Overheat," and the charging cycles are longer than the current one. 600, And visual inspection can also provide answers: if the back cover of the smartphone is swollen or the screen begins to move away from the frame, the battery needs to be changed urgently, as it can damage the display matrix.
When choosing a new battery for Redmi 4X (battery-model BM47) It is worth focusing on the capacity of 4100 mAh. the original batteries have a hologram of Xiaomi and QR-Pay attention to the voltage, it should be 3.85V. Don’t chase 5,000-strengthened batteries+ MAC from unknown brands: often it is a marketing ploy, and the real capacity there is even lower than the regular one.
⚠️ Note: Buying a battery without a protective charge (BMS) Make sure that there is a contact charge on the end of the new battery, similar to your old battery.
Low-quality analogues often don't have the correct labeling and may not be determined by the system or show the wrong percentage of charge, and it's better to overpay for a trusted supplier than take the phone down again in a month.
Tools and workplace preparation required
To successfully replace the battery with the Xiaomi Redmi 4X, you will need the minimum set of tools that any home craftsman will have. The main requirement is a clean, well-lit workplace. Small parts are easy to lose, and dust entering the case can lead to closure of contacts in the future. Cover the table with light cloth or paper so that the fallen screws do not get lost.
The list of equipment required includes:
- 🔧 Set of screwdrivers: cross (Phillips) size PH00 or PH000 hull-board.
- 🔪 Thin metal scalpel or blade for cutting adhesive base.
- 📱 Plastic blade (mediator) for snapping latches and working with plumes.
- 🌡️ A dryer or heating platform for softening the glue (optional, but desirable).
- 🧲 Magnetic mat or sheet of paper with a drawn scheme for rotor layout.
Be sure to turn off your smartphone before work begins. Although modern lithium-polymer batteries are less prone to fire than older ones, short-circuiting the battery contacts can disable the power controller on the motherboard. Do not use metal tools near the battery contacts and display plumes.
☑️ Checking readiness for repair
The process of disassembling the Redmi 4X hull
Redmi's disassembly 4X Start with the removal of the tray SIM-This is a standard procedure that prevents damage to the body on further opening. After removing the tray, turn the phone over and carefully examine the back metal panel. Unlike many modern models, there are no hidden screws under the stickers, but there is one important nuance.
At the bottom of the back cover, closer to the charging socket, is a decorative plastic insert antenna, and underneath that is a single screw that holds the lid. Carefully tuck the edge of this insert with a blade or a thin plastic card. Act without fanaticism, plastic can be fragile. Smack the edge, slowly snap the plug all the way.
You'll see a screw under the antenna that's taken off. Unscrew it with a cross screwdriver. Then you can start removing the main back cover. It's held on a two-piece glue and around the perimeter at the latches. Warming up the back with a hairdryer to 60 to 70 degrees (the hand must endure to the touch, but feel the heat) will make it much easier. Put the mediator in the junction between the frame and the cover and drive it around the perimeter, snapping the clips.
⚠️ Attention: Don't try to rip the lid off with a sharp jerk! Inside, at the top, is a fingerprint scanner plume that's glued to the lid.
Once the perimeter is past, don't open the lid completely. First, turn off the scanner plume, which is on the top of the circuit board and is connected to the board by a small connector. Gently bend the lid, put the connector in the nail or plastic blade, and disconnect it. Now you can put the lid aside.
What to do if the lid does not open?
Replacement of the battery and connection of plumes
When you remove the back cover, you'll see the inside of the smartphone, and the battery takes up most of the space and is covered with a black film that is both a heat pad and a hold. In the Redmi 4X, the battery is glued to the frame with double-sided tape, which loses its properties over time but often holds it tight.
The first thing you do is you disconnect the battery plume from the motherboard, which is on the top, next to the display connector, and you flip it off with a plastic blade, and then you remove the metal shield covering the connectors of the display and touchscreen, and it's screwed with a few screws (usually 3-4 screws), and you unscrew them, you take the plate off carefully.
Now you can take out the old battery, you can tuck it in by a special tongue (if you have one), or you can gently poke it around with a plastic card on different sides, trying not to damage the shell. If the battery is very tight, you can slightly warm the back of the smartphone with a hairdryer. Never prick the battery or bend it, it can cause a chemical reaction and fire.
Installation of the new battery is in reverse order:
- 🧹 Cleanse the seat of the remnants of old glue and dust.
- 🔋 Apply a new double-sided scotch (usually comes complete with battery) or use glue B-7000.
- 🔌 Install the battery and immediately connect the plume to the motherboard before clicking.
- 🖥️ Make sure the display plume is also securely connected.
Before the final assembly, it makes sense to check the system's performance. Press the power button. If the screen catches fire and the phone starts to load, you did everything right. If the screen is black but there's a vibration or a charging sound, check the connection of the display plume.
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For reliable fixation of the new battery, use high-quality double-sided 3M Scotch. Liquid glue is better applied with a thin layer around the perimeter, avoiding getting into the center where the controller is located.
Assembly of the device and checking leakage
Once the test is successful, you can start the final assembly, which requires careful stacking, so that the back cover is tight and clear, and you can put the metal plate over the display connectors and twist all the screws, and make sure that no wiring or plume is hit by the screws.
Then we plug the fingerprint scanner plume into the back cover, and that's the slimmest part of the build, and combine the plume connector with the back end on the lid, and press it carefully until it's fixed, and put the plume in the groove that's meant to be there so it doesn't get squeezed by the lid.
Now, we're going to put the back cover on. Start snapping it from the top of the camera, and then gradually move up to the bottom. The characteristic perimeter clicks will tell you that the plastic clips are in place. At the bottom of the antenna, make sure that the cover is tightly attached to the frame.
Table of the main assembly stages:
| Phase | Action. | Checkpoint |
|---|---|---|
| 1 | Installation of connector protection | All screws are swirling, the fee is not staggering. |
| 2 | Connecting the scanner | The plume is flat in the groove. |
| 3 | Installation of the lid | No perimeter clearances. |
| 4 | Fixing the antenna | The screw is twisted, the plug is in place. |
Completes the process of installing a decorative antenna stub and tray SIM-Turn on your phone and check the touchscreen, the camera and, of course, the fingerprint scanner, and if all the features work, you can consider replacing it successfully.
Calibration and features of the operation of the new battery
After replacing the battery with Xiaomi Redmi 4X, the system may not display the charge level correctly, because the power controller “remembers” the parameters of the old, worn-out cell.
The idea is simple: discharge the phone to zero. Then, without turning it on, charge it. When the indicator shows 100%, do not remove the cable for another 1-2 hours. Then turn on the phone. If the charge has dropped below 100%, put it on charge again (you can directly charge the phone) and wait for full charging. Repeat the cycle 2-3 times.
To extend the life of a new battery, follow the following simple rules:
- 🌡️ Avoid overheating: Do not leave your phone in the sun or near heaters.
- 🔋 Do not discharge to zero regularly: try to put on charging at 15-20%.
- 🔌 Use original or certified chargers.
⚠️ Warning: Don't use the "calibration" apps from the Play Market. They're often useless and waste battery life. The best calibration is the natural charge-discharge cycle.
Compliance with these recommendations will allow the new battery to work out its life, ensuring the stable operation of your Redmi 4X for a long time. Remember that lithium polymer batteries do not have a “memory effect”, so you can put them on charge at any time.
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Proper calibration in the first days of use is the key to accurately displaying the percentage of charge and long life of the new battery.