The Xiaomi Redmi Note 5, launched in 2018, has earned a reputation as one of the most reliable “people’s” devices of its time. However, even the most hardy devices require a replacement power source over time, as the chemical composition of lithium polymer cells degrades after hundreds of charge cycles. Owners often wonder what kind of battery is in their device to find a worthy replacement and extend the life of the gadget.
In this article, we will discuss in detail the technical characteristics of the standard battery, consider compatible models for the global version and the Indian version of the Redmi Note 5 Pro. You will learn how to correctly diagnose wear, what tools will be required for self-replacement and what to look for when buying a new part to avoid problems with the power controller.
The main task of the user at this point is not just to find the battery of the right size, but also to make sure that it is safe and meets the declared characteristics. The market is oversaturated with counterfeit, so knowing the exact marking and appearance of the original becomes a critical skill.
Technical characteristics and battery model
The standard power supply for the Xiaomi Redmi Note 5 (global version) and Redmi Note 5 Pro (Chinese and Indian versions) is a lithium polymer battery with factory code BN46. It is a unified part that is physically and software-friendly for both devices, despite differences in processors and cameras. The nominal capacity is 4000 mAh, which for a 5.99-inch FullHD+ screen is the optimal indicator, providing up to two days of moderate operation.
The battery's operating voltage is 3.85V and the maximum voltage at full charge reaches 4.4V. It is important to understand that the energy density in modern Li-Pol cells allows you to maintain compact dimensions at high capacity. The dimensions of the BN46 battery are selected to densely fill the inner space of the housing, leaving minimal gaps for heat sinks and plumes.
Inside the case, there's not just a chemical jar, but a BMS (Battery Management System) board that protects the device from overheating, overcharging and short circuiting. It's this circuit board that communicates with the smartphone motherboard, transmitting data about charge levels and temperature. Using substandard analogues without proper protection can cause the power controller to fail or even fire.
What is the difference between BN46 and BN45?
For visual control of the conformity of the part, check the table below, which gives the main parameters:
| Parameter | Meaning | Note |
|---|---|---|
| Model | BN46 | Primary identifier |
| Type | Li-Polymer | Lithium-polymer |
| Capacity (nom.) | 4,000 mAh | Typical 3900-4100 mAh |
| Tension. | 3.85B | Max. 4.4B. |
How to distinguish the original battery from a fake
The spare parts market for the popular Redmi Note 5 model is crowded with low-quality copies.The original Xiaomi battery has a clear labeling applied with a laser or quality printing that does not erase when lightly rubbed with a finger, QR-code, serial number and production date.
Pay attention to the build quality and materials. The original battery should not have bloating, skewing or glue marks on the contacts. The connection plume should be flexible but elastic, with neatly soldered contacts. Copies often sin with rigid plumes that can move away from the connector at the first disassembly or, conversely, break during installation.
- 🔍 Barcode check: scan QR-Battery code – it must lead to the official authentication site or contain a logical serial number that matches the batch.
- ⚖️ Part weight: The original battery weighs around 75-80 Too light batteries often have less actual capacity due to the use of cheap materials.
- 🏷️ Logos: the Mi or Xiaomi logo should be clear, without blurring edges and typos in writing specifications.
💡
When buying a battery, smell it (carefully). Original Li-Pol cells don't have a sharp chemical smell. The smell of solvent or burn indicates leakage or use of cheap glue.
One of the most reliable ways to check is software. After you install a new battery, connect your smartphone to your PC and run the Mi Flash Tool or engineering menu. The Battery Health bar should display the "Good" status and the number of charge cycles close to zero (for the new battery).
Signs of wear and the need for replacement
The average life of a lithium polymer battery is 500-800 full charge-discharge cycles, which is equivalent to 2-3 years of active use. You can see that your Redmi Note 5 battery has run out of life, from a number of indirect and direct indications. Ignoring these symptoms can lead to a sudden shutdown of the phone at the most inopportune moment.
The first and most obvious sign is the bloating of the body, and if the smartphone is no longer flat on the table and starts to rotate when you press the corner, or if the back cover (if it's removable or unstuck) starts to move away, that's a critical signal, and there are chemical reactions inside the battery that release gases, which makes it fire-prone.
⚠️ Warning: If you notice a bloating battery, stop charging the device immediately. Do not try to punctur or compress the ballooned battery - this can cause the electrolyte to ignite. Remove it as carefully as possible without damaging the shell.
Other symptoms of degradation include:
- 📉 Sharp jumps in percentage charge: the phone shows 30%, then abruptly switches off or goes to 5%.
- ❄️ Heat: the body warms up strongly even with simple tasks (calls, SMS) or while charging.
- 🔌 Charging problems: the phone takes a long time to gain the first percentage or, conversely, shoots off charging on the phone. 80-90%.
Also, you need to consider the software aspect. Sometimes the system will miscalibrate the battery. Before replacing, try to do a full calibration cycle: discharge the phone to zero before turning it off, then charge to 100% when it's off, then turn it on and finish it to 100% again. If the problem is not gone, you need to physically replace the element.
Tools and preparation for replacement
Replacing the battery in Xiaomi Redmi Note 5 requires accuracy and the presence of a special tool. The design of the smartphone involves disassembling from the screen, since the back cover here is not the main access element (although in some versions it is removable, it is better to work through the front panel for a qualitative replacement or carefully heating the rear window). However, the classic and safest method for this model is dismantling through the screen, since the rear window is glued very strongly and easily bursts.
You will need the following set of tools:
- 🔥 Thermophen or heating pad: to soften the adhesive layer under the display (temperature) 80-90°C).
- 💳 Plastic blades and mediators: metal tools can damage plumes or break the matrix.
- 🔧 Screwdrivers: Phillips cross #00 and #000 for twisting frame screws.
- 🧴 Clay. B-7000 or T-7000: to fix the screen and battery after completion of work.
⚠️ Warning: Before any work begins, be sure to turn off your smartphone. Shutting down the battery is the first step after removing the top cover of the frame. Do not turn off the plume while the phone is on - this can cause the backlight of the display or power controller to burn.
Prepare the workspace: it should be well lit, spacious and not have a fluffy coating, so that small screws do not get lost. It is recommended to use a magnetic mat or organizer for screws, since the Redmi Note 5 design uses screws of different lengths, and you can not confuse their installation places.
☑️ Ready for replacement
Step-by-step instructions for replacing the battery
The replacement process begins with heating the perimeter of the display. Carefully warm the edges for 2-3 minutes, without holding the hair dryer for a long time in one place, so as not to damage the matrix or plastic frame. After heating with a suction cup, raise the edge of the screen and insert a plastic card, gradually passing along the perimeter, peeling the display off the body.
Once the screen is raised, don't pull it sharply -- it's connected to the board by plumes. Open your smartphone like a book and find a metal protective plate covering the connectors.