The Xiaomi Redmi 5 Plus, launched in early 2018, has proven to be a reliable device with excellent autonomy. However, time is inexorable, and after a few years of active use, the capacity of the built-in lithium polymer battery inevitably decreases. Users begin to notice that the phone discharges in half a day, warms up when charging or even turns off at 20% charge.
This is a question of replacing the battery, and many service centers offer their services, but the cost of the work can be a significant part of the cost of the device itself in the secondary market, and if you have minimal electronics and accuracy skills, then self-replacing will be a cost-effective solution.
In this article, we will discuss in detail the process of dismantling the old battery and installing a new one. We will pay special attention to the nuances of disassembling the body, since the design of the Redmi 5 Plus has its own features of attaching the rear cover and plumes. The right approach will allow you to extend the life of your gadget without risking damage to other components.
Diagnostics and workplace preparation
Before you start physically disassembling the Redmi 5 Plus, you need to make sure that the problem lies in the wear of the battery. Sometimes rapid discharge is caused by software failures or background processes. Check the usage statistics in the Settings → Battery menu. If you see sharp spikes in percentages or bloating, then a replacement is necessary.
You'll need to have a clean, well-lit space to do this, and you'll need to have small parts like screws that are easy to lose on a carpet or table, and you'll need to use a magnetic mat or screw sorter to avoid confusing the different lengths of the fixtures when you build them.
You will need the following tools and materials:
- 🔧 Set of screwdrivers (cross-haired) PH000 flat)
- 🎈 Suction or mediator for opening the body
- 💳 Plastic card or spatula for disconnecting plumes
- 🧴 Isopropyl alcohol or special glue liquid
- 🌡️ dryer or warmer
It is important to prepare the isopropyl alcohol in advance, as it will be needed to dissolve the adhesive base. Also make sure the new battery is compatible with the BN44 model (standard labeling for this series).
Disassembly of the hull and removal of the back cover
Xiaomi Redmi 5 Plus design involves using a glue layer around the perimeter of the back panel for fixation, which is done to improve tightness and aesthetics, but greatly complicates the dismantling process.
Use a hair dryer to warm up the edges of the back cover evenly. Keep the heat source at a distance of 3-5 cm for 2-3 minutes. Don't overheat the center part where the camera and main boards are located, so as not to damage the optical stabilizer or display. The temperature should not be too high, enough tangible heat to touch.
⚠️ Warning: If you feel the glass is too hot, stop heating.Excessive temperature can damage OLED-matrix or lead to the dissection of the display.
After warming up, insert a suction cup at the bottom of the back cover, closer to the edge. Pull up carefully, creating a small gap. Insert a mediator or a thin plastic card into the resulting gap. Move the tool along the perimeter, cutting the glue layer. Move smoothly, without jerking, so as not to break the plastic latches.
Be especially careful in the area of the camera module and fingerprint scanner, if it is integrated into the cover (in this model, the scanner is on the back and connected by a plume). Do not pull the cover too much until you make sure that all the adhesive connections are severed. The scanner plume is quite short and easily breaks when handled carelessly.
Disabling plumes and dismantling the protective plate
When you successfully remove the back cover, you'll see the interior of your smartphone, and most of the components are covered with a black plastic safety plate that's screwed to the metal frame. The Redmi 5 Plus uses multiple screws of different lengths, so it's better to remember or photograph them.
Unscrew all the visible screws that fix the protective plate. 10-12 They're located around the perimeter of the board and in the center, and use a magnetic screwdriver to keep the screws from falling inside the case, and after you remove the fastener, carefully remove the plastic lining by lifting it with a plastic blade.
Under the plate, you'll see the motherboard, the plume connectors, and the battery connector. The first thing you need to do is disconnect the battery plume from the motherboard. This is a critical safety step. Use a plastic blade or nail to push the connector upwards. Don't use metal tools to avoid short circuits.
After the power outage, you can safely disconnect the remaining plumes:
- 🔌 The main camera module plume
- 📡 Antenna cable (located diagonally)
- 🔊 Lower board plume (dynamics and microphone)
- 🖱️ Fingerprint scanner plume
The antenna cable is often attached with special latches. Be careful when you snap them off, because they're very fragile. If the antenna wire interferes with access to the lower board screws, you can carefully pull it aside without completely disconnecting it, if the length allows.
☑️ Check before removing the battery
Removal of the old battery
The battery in the Redmi 5 Plus (model BN44) is glued to the inside of the case on double-sided tape. Over time, the glue loses its properties or, conversely, polymerizes, making extraction difficult. Force should not be applied, since damage to the battery shell can lead to fire.
Use a hair dryer again to warm up the battery area through the open rear window, 1-2 minutes of moderate heating is enough, then apply a few drops of isopropyl alcohol or a special liquid (for example, B-7000) under the edges of the battery, the liquid should leak under the battery and dissolve the adhesive layer.
Use a plastic card or a special blade with a neckline to rattle the battery. Start at one of the lower corners. Move the tool parallel to the plane of the housing, gradually separating the battery from the frame. If you feel strong resistance, add more alcohol and wait.
Some versions have a stretchable tape to make it easier to extract. Pull the tongue (usually black or blue) slowly and evenly. If the tape is broken or missing, continue with the solvent and the shoulder blade. Never use sharp metal objects to avoid piercing the battery case.
⚠️ Warning: When removing the battery, watch out for the plume that can be glued to or under the battery itself.
Installation of a new battery and assembly
Before installing a new power supply, you need to clear the seat of the residue of old glue. Use a fabric slightly moistened with alcohol to degrease the surface of the metal frame. A clean surface will provide better adhesion of the new adhesive layer.
New batteries often come with a glue layer already applied. If there is no glue, use double-sided electronics tape or a thin layer of B-7000 glue. It is strictly forbidden to use superglue (cyanacrylate) as it hardens and can damage the battery the next time you replace it.
Connect the battery plume to the motherboard before you click, make sure the contacts are in exactly the same, and then you can temporarily install the protective plate and try to turn the device on by pressing the power button, and if the phone is on and shows the charge, then the installation was successful.
The reverse assembly process follows:
- Put the antenna cable in the original slots.
- Roll the protective plastic plate with all screws.
- Connect all other plumes (camera, screen, lower board).
- Apply a new adhesive layer to the frame of the case or use a ready-made adhesive circuit.
- Press the back cover and fix it with rubber bands for 15-20 minutes.
What to do if the phone is not turned on?
Calibration and primary charging
After a successful battery replacement, Xiaomi Redmi 5 Plus is recommended to conduct a calibration procedure, which will help the system correctly display the level of charge and work correctly energy saving algorithms. Modern power controllers are smart, but initial calibration will not be superfluous.
Discharge the phone until it's completely turned off naturally. Then set it to charge when it's off to 100%. After reaching full charge, leave it on charge for another 1-2 hours. Then turn on the phone and check the charge level. If it's dropped, reconnect to 100%.
The table below gives the main battery parameters for comparison:
| Parameter | Original BN44 | Quality copy | Cheap copy |
|---|---|---|---|
| Capacity | 4000 mAh | 3800-4000 mAh | 2500-3000 mAh |
| Tension. | 3.85 V | 3.85 V | 3.7-3.8 V |
| Cycle resource | 500+ cycles | 300-400 cycles | 100-150 cycles |
| Weight. | ~85g | ~80-85g | ~60-70g |
Pay attention to the weight of the battery when you buy. Lithium has a certain density, and a significant deviation in the lower direction often indicates a low real capacity.
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Keep the check and packaging from the new battery for at least 3 months, a period in which factory defects or rapid wear and tear of substandard items usually occur.
Frequently Asked Questions (FAQ)
Can I charge my phone while changing the battery?
What to do if an old battery is blown?
Why does the phone say "Unknown battery"?
Do I need to reset the settings after replacement?
How long does the glue dry after assembly?
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A high-quality battery replacement returns 80-90% of its original autonomy to the smartphone, making the device relevant for another 1-2 years of use.