Xiaomi Redmi Note 3 is a well-deserved legend in the budget segment, but even the most reliable devices are spared time. If your phone starts to discharge quickly, turn off 20-30% of charge or the case is inflated, then it’s time to replace the energy element. This procedure requires accuracy, but it is quite feasible at home with a minimum set of tools and accurate follow the instructions.
It's important to understand that self-repair removes warranty obligations, but for a device released several years ago, this is often the only economically viable option. In the process, we will discuss the choice of quality components, safe opening of the metal case and proper calibration of the new battery.
Before you start, make sure you have a free, well-lit workplace, and the lack of hassle and hassle is key to the successful completion of the operation. Below we will discuss in detail the entire process, from tool preparation to the final assembly and testing of the gadget.
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. Software failures can sometimes simulate a quick discharge, so you should try to reset the settings or reflash the device. If after reinstalling the Redmi Note 3 still loses charge as quickly and the screen displays incorrect percentages, then a replacement is inevitable.
When choosing a new battery, it is critical to avoid cheap analogues of unknown manufacturers. The market is saturated with fakes that can not only hold the charge, but also damage the motherboard power controller. The original or quality analogue from a proven brand (for example, Nohon or Baseus) will last much longer.
⚠️ Warning: A billowing battery can damage the display or touchscreen with its pressure from the inside. If you notice that the screen has started to move away from the frame or colored spots appear, remove the battery as soon as possible.
For the standard version of the Redmi Note 3 (Snapdragon processor), the standard capacity is 4000 mAh, and for the version of the Special Edition (SE) - 4050 mAh. Using a larger battery in a metal case can be physically impossible or dangerous.
- 🔋 Capacity: Must match the original (4000 mAh), otherwise the controller may not display charge correctly.
- 🏷️ Marking: the original Xiaomi battery always has a hologram and QR-code that can be checked on the official website.
- 🔌 Connector: Make sure the location of the contact area matches your module, as modifications may differ.
Don't chase a low price. A good battery can't cost 300-400 rubles. The savings in this case will lead to re-repair in 2-3 months, which will eventually cost more.
The success of the operation depends on preparation for 50%. Xiaomi Redmi Note 3 has an all-metal body, which makes it difficult to access the insides compared to plastic counterparts. You will need a specific set of tools that you better prepare in advance, so as not to look for a screwdriver in the midst of the process.
The main challenge is to attach the back cover to the glue and screws under the display. To safely open it will require heating the edges of the case. A normal hair dryer may not be enough, it is better to use a temperature-adjusted building hair dryer or a special heating pad for smartphones.
Pay special attention to the cleanliness of the desktop. Small cogs tend to roll into the most unexpected places, and losing even one of them can make it difficult to assemble. It is recommended to use a magnetic mat or spread out a white fabric on which all the details are clearly visible.
- 🔧 Screwdrivers: Phillips cross #000 for main screws and Torx T5 button-hole.
- 🧤 Protection: Antistatic gloves will help to avoid fat on contacts and static discharge.
- 🧪 Clay: B-7000 or T-7000 for fixing the back cover after assembly.
Also prepare the screw sorting containers. Redmi Note 3 uses screws of different lengths, and if you screw a long screw into a short hole, you can punch the motherboard, which will lead to fatal consequences.
The process of disassembling the smartphone
We start with the hardest part, the back cover, and the first thing you do is, you extract it. SIM-Then you have to unscrew the two screws at the bottom of the case near the charging socket, and then you have to gently heat the perimeter of the back cover with a hair dryer to a temperature of about 60-70 Plastic should be warm, but not hot to the touch.
Using a suction cup, create a small gap between the lid and the frame in the tray area. SIM-Insert a plastic blade into the gap, and without undue effort, drive it along the perimeter, gradually snapping the plastic latches away. Move slowly so that the fragile plastic latches do not break.
⚠️ Warning: Do not use metal objects (knives, blades) to pluck the lid. Metal may damage antenna inserts or break through the insulation, which will lead to a short circuit.
Once the lid is removed, the main board will be accessed, but the battery in the Redmi Note 3 is hidden under a metal screen that is part of the internal bezels, and you need to twist a lot of screws around the perimeter and remove the plastic frame on which the volume swing and the power button are located.
The secret of removing the frame with buttons
The power and volume button frame is held on very thin plumes. When you remove it, be extremely careful: first unplug the plumes from the motherboard, and only then carefully lift the frame so that the thin conductors do not break. When the frame is removed, you will see the battery closed with another metal sheet with the Mi logo. This sheet is screwed with several screws and glued. Carefully unscrew them and remove the metal plate. Now access to the battery is open. Removal of the old battery and installation of the new battery is safe. You can use the Xiaomi battery in the middle of the fecelet to heat it up the fecelet, and use it in the upper case, you can use it in the fecelet in the upper one to the upper one. Under the gap, carefully insert a plastic card or a spatula, and as you make sawing movements, cut off the glue layer. Move from the top edge to the bottom, gradually separating the battery. After removing the old battery, you need to carefully clean the landing place of the residue of old glue. Use isopropyl alcohol and soft fabric. The surface must be perfectly clean and fat-free for a good adhesion of the new cell. The new battery is installed in reverse order. Apply a thin layer of special glue (B-7000) on the body or on the battery itself, let it dry a little (1-2 Then press the battery tightly, connect the battery plume to the motherboard before the characteristic click. 🧹 Cleaning: Remove all the glue residues so that the new battery lays down exactly without distortions. 🔌 Connection: Make sure the connector sits tightly and smoothly, without distortions. ⏱️ Fixing: Press the battery with your hand on 30-60 You take the time to twist all the screws right away. First, check if the phone is turning on and responding to charging. This will save you time if you need to reconnect. 3 It requires careful sequence, first you put a metal plate over the battery and you lock it in with the screws, and then you put a button frame in place, and you plug in the volume and power button plumes. Only then can you install the main board if it's been removed, or plug in the main plumes of the display. It's important to stow the plumes properly. They should lie in their guide channels and not be squeezed. Once all the plumes (display, touchscreen, main plume) are connected, you can temporarily (without screws) install the back cover and try to turn the device on, and if the phone is turned on, shows charging and reacts to touch, you can start the final assembly. Twirl all the frame screws and the back cover. Use glue to fix the lid with a thin strip around the perimeter. Press the edges and lock the device with rubber bands on the perimeter. 1-2 After the first assembly, you need to calibrate the battery, which is a process that helps the system correctly determine the level of charge. Completely discharge the phone before turning off, then charge it (can be turned off) to the point where it is not charged. 100%. After the 100% hold on to the charger. 1-2 hour. Calibration Step Action 1 Full Discharge Reset Charge Controller 2 Charging to 100% (off) Fill cells to maximum 3 Recharge 1-2 hours Cell Balancing 4 Full Discharge in Operation Real Capacity Check Repeat Full Discharge-Full Charge cycle 1-2 more times in normal use mode. This will help the power controller "learn" the new battery capacity. Typical errors and troubleshooting Even experienced masters sometimes encounter problems after battery replacement. One of the frequent mistakes is poor connector contact. If the phone doesn't turn on a full charge 1-2 times in normal use mode, it will require another battery reload or reloading. If the phone is 1 percent and shuts down immediately, or the percentage of charge jumps (50 percent, 10 percent), it's likely that the battery controller is not interacting properly with the phone's controller. ⚠️ Warning: If the phone starts to warm up in idle mode after replacing the battery, turn it off immediately, which may indicate a short circuit inside the battery or a wrong connection, and users often forget about screws of different lengths. If you find one part of the body protruding or creaking after assembly, maybe a long screw is twisted into a short hole, hitting a board and lifting the structure, in which case the disassembly will have to be repeated. Problems with the touchscreen after assembly are often due to the fact that the touchscreen plume has been clamped or poorly snapped. Check the connection reliability in the connector area on the motherboard. Sometimes it helps to gently press the connector area with your finger when the phone is on (carefully!). 📉 Charge jumps: a sign of poor quality battery or need for calibration. 📵 Not catching the network: it is possible that during the assembly was damaged antenna contact or plume. 🔊 Wheezing sound: often occurs if you pass the speaker during assembly or do not get into the seal. If you are faced with a situation where the phone turns on, but the image on the screen is missing (although there is backlight), check the display plume. In Redmi Note 3, it is quite long and with a sloppy build could jump out of the groove. --> Frequently asked questions (FAQ) Can you replace the battery in the Redmi Note 3 without removing the motherboard? Theoretically, because the battery is opened after removing the metal bezel with the buttons. But for convenience and safety, especially if you're doing it for the first time, it's best to take the board off so you don't damage the plumes when you manipulate glue and tools. 30-40% This is a classic sign of calibrating or installing a defective/incompatible battery. The power controller thinks there's still a charge, but the voltage on the new cell drops dramatically under load. Try the calibration cycles described above. Which glue is best used to fix the lid? The optimal choice is rubber-based adhesives, such as: B-7000 or T-7000. They remain elastic once dry, allowing the phone to reopen in the future without the risk of breaking the case, unlike superglue (cyanacrylate), which makes plastic brittle. How long does it take to replace the battery? 20-30 minute. For a newcomer to the first time to see the Xiaomi Redmi Note 3 disassembled, it’s worth pawning around 1-1.5 hours, given the time to heat the glue, carefully snap the latches and wait for the fixing glue to dry out. Is it safe to use a larger battery (4500-5000 mAh)? In a metal case, Redmi Note 3 is highly discouraged. High-capacity batteries often have increased thickness, which will create excessive pressure on the display and can lead to its crack. In addition, the regular power controller can work with an abnormal power supply.