Xiaomi Redmi Note Smartphone 7 It remains a popular device even years after its release, but its battery is still in use. 4000 The mAch inevitably loses capacity. If you notice that the phone runs out in a few hours, it turns off when you're in the middle of a cell. 20-30% When you're charging or overheating while you're charging, it's time to replace the battery. In this article, we're going to talk about how to do it yourself without going to the service center.
The process of replacing the battery with the Redmi Note 7 requires accuracy and the right tools, but it is quite feasible at home. We will describe each step in detail, from choosing a new battery to the final assembly of the device, and pay special attention to critical points that are often missed in standard instructions, such as the correct calibration of the power controller after replacement.
Signs of a faulty battery on the Redmi Note 7
Before you start replacing, make sure the battery is the problem.
- 🔋 Phone's running out of power. 2-3 hours with moderate use (social networks, messengers)
- 🔌 The percentage of charge "jumps" (for example, with a 40% straight away 15%) or the phone is turned off when 20-30%
- 🔥 The body is noticeably heated in the battery area (even without load)
- ⚡ Charging is extremely slow or interrupted (especially on wireless charging)
- 📉 B Settings → Battery → The state of the battery capacity shows less than 70% of the original
If you see at least 2-3 items from the list, the battery should be replaced. Ignoring the problems can lead to a sudden failure of the phone or even bloating of the battery, which is dangerous for the device.
⚠️ Warning: If the Redmi Note 7 body is already swollen (gaps between the screen and the frame, bulges on the back) - do not try to disassemble the phone yourself!
What battery to choose for replacement
The original battery for Xiaomi Redmi Note 7 is marked BM47 or DM47 (depending on the batch) and a capacity of 4000 mAh.
| Parameter | Original | Quality analogue | Cheap analogue (risks) |
|---|---|---|---|
| Capacity | 4,000 mAh | 4,000–4100 mAh | 3500–3800 mAh (rapid wear) |
| Tension. | 3.85V | 3.8–3.85V | 4.2V and above (overheating) |
| Controller | Built-in (NTC thermistor) | Built-in (with protection from KZ) | No thermistor (risk of fire) |
| Manufacturer | ATL, Sunwoda | Desay, Coslight | No-name (China without certificates) |
The best options to buy:
- 🛒 The original Xiaomi (article) MBJ405480) — It's expensive, but it's reliable, it's sold on a branded service.
- 🔋 Analogues from Baseus or Remax – proven brands with a guarantee of 6-12 months.
- 🔧 Kits with tools (for example, on AliExpress) - beneficial if there are no screwdrivers.
⚠️ Warning: Avoid batteries labeled "High Capacity" (e.g., 5000mAh) that are often overrated and can damage the phone's power controller.
Required tools for replacement
To disassemble the Redmi Note 7 will need:
Plastic blades (mediators) – 2-3 pcs.|The screwdriver. PH00 (magnetic)|Screen suction cup (optional)|Tweezers with curved ends|Dryer or thermo-air station (for glue)|Thin plastic card (for example, SIM card)|Antistatic bracelet (recommended)-->
Where to buy it?
- 🛠️ Smartphone repair kits (e.g. iFixit Pro Tech Toolkit) – a universal solution.
- 🔧 Individual tools on AliExpress or in radio stores (cheaper, but longer delivery).
- 📱 In service centers often sell tools "on a day" (ask when buying a battery).
Important: Don't use metal blades or knives - they will damage plumes and the body.Plastic mediators cost pennies, but they will save your phone!
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Before disassembling, take a photo of each stage on a friend's phone or tablet, which will help to properly assemble the device if you forget the location of the parts.
Step-by-step instructions for replacing the battery
We're going to start disassembling. Turn off the phone and take it out. SIM-Work on a clean table with good lighting.
1. Removal of the back cover
The Redmi Note 7 back is glued, so:
- Heat the edge of the body with a hair dryer (~60°C) for 1-2 minutes. This will soften the glue.
- Insert the plastic blade into the gap between the lid and the frame (start at the bottom corner where the charging connector is).
- Carefully drive the shoulder blade around the perimeter, separating the lid. If the glue does not lend itself, warm up again.
Don't force it! There are plumes of fingerprint scanners and antennas under the lid, and they're easy to tear.
2. Battery shutdown
When you take the lid off, you'll see a battery with a black film, and the first thing you do is unplug it from the motherboard.
- Unscrew 2 screws that fix the metal plate over the battery connector (driverdriver PH00).
- Put a plastic blade on the connector and gently unplug the plume.
What happens if you don’t turn off the battery before work?
3. Removal of the old battery
The battery is glued to the body to remove it.
- Put the battery on the side with a plastic card (where there are no plumes).
- Pull slowly with the glue. If the battery doesn't respond, heat it with a hair dryer (not above 70°C!).
- Dispose of your old battery according to local regulations (don’t throw it away in regular trash!).
Installation of a new battery
Before installing the new battery:
- 🧹 Clean the place under the battery from glue residues (use alcohol and cotton swab).
- 🔌 Check that the connector of the new battery coincides with the connector on the board.
- 📏 Make sure the battery is flat - without distortions and gaps.
Stick the battery with double-sided tape (complete with the new battery) or a special glue B-7000. Connect the plume to the motherboard.
5. Build the phone
Collect the phone in reverse order:
- Install the back cover, making sure all plumes are in place.
- Turn the screws (do not pull!).
- Warm up the edges with a hair dryer and press the lid for reliable fixation.
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After assembly, be sure to check the phone for performance before installation. SIM-If something goes wrong, it'll be easier to disassemble.
Calibration of the new battery
The new battery requires proper calibration to ensure that the power controller correctly displays the charge level.
- Use your phone before you turn off automatically (do not charge even if a low charge warning appears).
- Full Charging: Connect the original RAM and charge up to 100% without interruptions (preferably off).
- Recycle: Discharge to 0% and recharge to 100%.
Once calibrated, the battery capacity will be displayed accurately, and the phone’s life will increase by 20–30% compared to the old battery.
⚠️ Warning: If the phone doesn't turn on or charge after the replacement, check: Is the battery connector properly connected (sometimes it flies off when assembled); is the charging plume damaged (look at the breaks); is the contacts on the board closed (check under the magnifying glass). In 90 percent of cases, the problem is solved by redisassembling and checking connections, and frequent errors and how to avoid them, even experienced users sometimes make mistakes when replacing the battery. Error Consequences How to avoid Using metal tools Scratches on the body, damage to plumes Only plastic blades and mediators! Battery overheating with a hairdryer (>80°C) Bloating or ignition of the battery Keep the temperature at 60–70°C Unswitched battery when disassembling Short circuit, burnt controller Disable the battery first thing Installation of the battery with another voltage Fast wear or overheat Check the marking: there should be 3.8–3.85V Expert advice: If you are disassembling the phone for the first time, practice on an old unnecessary device or watch the Redmi Note 7 video disassembly on YouTube. Visual guide will help to avoid errors. How much does it cost to replace the service vs self The cost of replacing the battery varies depending on the region and the selected service: 🏠 Self-replacement: Battery: 800-1500 ₽ (analogue / 2000-3000 ₽ (Original) Instruments: 300-1000 ₽ (If you buy a set) Total: 1100-4000 ₽ 🔧 Service center: Official Xiaomi: 3,500–5000 ₽ (Original battery) Local workshops: 1500–2500 ₽ (Self-replacement is 30-50% more profitable, but it takes time and care. If you are not sure about your skills, you should contact a professional, especially if the phone is warranty (self-repair will cancel it). FAQ: Frequently asked questions: Can you replace the battery with a Redmi Note 7 without a hair dryer? Yes, but it is more difficult. Alternative ways: Use hot water in the bag (apply to the lid for 1-2 minutes). Apply isopropyl alcohol, which dissolves the glue (but it works slowly). However, the hair dryer remains the most reliable and fastest method. How to check that the new battery is original? The original Xiaomi battery has: Clear labeling BM47 or DM47 Serial number matching the number on the package, smooth welding seams on the contacts (fakes often have curves), buy only from trusted sellers with a guarantee! What to do if the phone dies quickly after replacing? Possible reasons and solutions: Uncalibrated battery → Conduct 2-3 cycles of full discharge/charging. → Check the Settings. → Battery → Use and disable power-intensive applications. Charging plume damaged → Take the phone apart and check the connections. Can I put a larger battery (e.g., 5,000 mAh) on it? Absolutely not! The Redmi Note 7 power controller is designed to run on the original battery, and if you install a battery with different parameters, you'll see: Overheating and bloating, rapid wear on the charging controller, loss of warranty (if it's still valid), how do you dispose of an old battery? Lithium-ion batteries can't be thrown away in regular trash! recycling options: 🔄 Take to the reception points of electronics (available in every city). 📦 Take to the service center Xiaomi – there are containers for batteries. ♻️ Use the Ecotechnologies program (in some regions, discounts are given for repairs for battery delivery).