Why Xiaomi Redmi 4X Battery Fails and When to Change It
Xiaomi Redmi 4X (codenamed santoni) was released in 2017 and became one of the most popular budget devices of the brand. However, even with careful use after 2-3 years, its battery begins to “die”: the phone discharges in a few hours, turns off at 20-30% charge or refuses to turn on at all, the reason for the degradation of lithium-ion cells, which is accelerated by frequent charging, overheating or using low-quality RAM.
If your Redmi 4X is less than a day old and you see a message in your battery settings (Settings → Battery) saying “Battery condition is bad,” it’s time to think about replacing it. In this article, we’ll discuss how to change your battery without damaging your phone, what tools you’ll need and what to look for when choosing a new battery.
⚠️ Replacement of the battery on Xiaomi Redmi 4X It requires care, it can cause the plumes to break off, it can cause the contacts to break off, it can cause the battery to burn, and if you're not sure about your skills, you should go to the service center.
Signs that Xiaomi Redmi 4X battery needs replacement
How do you know that the battery is the problem, not the software failure or the power controller malfunction?
- 🔋 The phone discharges in 3-4 hours with a minimum load (social networks, instant messengers).
- 📉 The percentage of charge “jumps”: for example, from 50% immediately drops to 15%.
- 🔌 The device does not turn on without charging, even if it shows 10-20% charge.
- ⚡ The battery is swelling (this is visible from the raised back cover or screen glass).
- 🌡️ The phone warms up when charging or working.
If you have at least 2-3 items on your Redmi 4X list, it is likely the battery is to blame.
- In the phone app, type ##4636##.
- Select the item "Battery Information".
- If it shows bad, unknown, or below 80%, you should change the battery.
What battery to choose for Xiaomi Redmi 4X: original vs analogues
The original battery for the Redmi 4X is marked BM47 and a capacity of 4100 mAh. However, after 2019, Xiaomi stopped supplying batteries for this model retail, so you will have to choose among analogues.
| Parameter | Original (BM47) | Quality analogue | Cheap analogue |
|---|---|---|---|
| Capacity | 4100 mAh | 4000-4200 mAh | 3,500 mAh |
| Tension. | 3.85 In | 3.8–3.85 In | 3.7 B or 4.2 B |
| Controller | Built-in (KZ protection) | Built-in | Absent or simplified |
| Price (2026) | No, not on sale. | 800–1500 ₽ | 300–600 ₽ |
Where to buy:
- 🛒 AliExpress – Look for sellers with a rating above 98% and reviews about compatibility with Redmi 4X. Popular brands: Baseus, Remax.
- 🏬 Offline stores - like "Svyaznoy" or "MTS", but there are often inflated prices.
- 🔧 Service centers – can offer a battery with a guarantee, but the price will be higher.
Critical: Don’t buy batteries with a capacity above 4200 mAh – they are not designed for the Redmi 4X and can damage the power controller. Also avoid batteries without labeling or with labels like “Ultra Power” – these are low-resource fakes.
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Before buying, check the size of the battery: the original has dimensions of 68 × 65 × 3.85 mm. Even a slight deviation can interfere with the installation.
Preparing for replacement: security tools and measures
To replace the battery with Xiaomi Redmi 4X, you will need:
- 🔧 Plastic blades (mediators) - to separate the body.
- ⚙️ The screwdriver (PH00 or PH0) — screw.
- 🔥 Hair dryer or thermo-air station - for softening the glue.
- 🧲 Suction - to slap the back cover.
- 🛡️ Gloves and safety glasses in case of battery damage.
- 🔋 New battery tested for compatibility.
⚠️ Attention: Lithium-ion batteries can ignite when punctured or heated. Never use metal tools to tamper with the battery - only plastic blades. If the battery is swollen, the replacement is best trusted by professionals.
Also prepare the workplace:
- Work on a clean table with good lighting.
- Turn off the phone and remove it. SIM-memory-card.
- Discharge the battery to 20-30%, which will reduce the risk of short circuit.
Turn off the phone and remove the cards|Discharge the battery to 20-30%|Prepare tools|Wear gloves and glasses|Check the new battery for integrity-->
Step-by-step: how to disassemble Xiaomi Redmi 4X and replace the battery
The replacement process consists of 5 steps. Follow the instructions carefully so as not to damage the plumes or contacts.
Step 1: Removing the back cover
The Redmi 4X back cover is glued around the perimeter to remove it.
- Heat the phone edge with a hair dryer (60–70°C) for 1-2 minutes.
- Suction the lid on the charging connector.
- Carefully conduct a plastic spatula around the perimeter, separating the glue.
⚠️ Warning: Don't use force, there are plumes of the fingerprint scanner and antenna under the lid. If the lid doesn't respond, warm up again.
Step 2: Turn off the plumes
After removing the cover, you will see:
- Battery (black rectangle with contacts).
- The fingerprint scanner plume (thin cable at the top edge).
- Main board plume (wide connector in the center).
Turn off all the plumes with a plastic blade, pulling the tongues of the connectors.
Step 3: Remove the old battery
The battery is glued to the body to remove it.
- Put a plastic shoulder blade on the battery from any angle.
- Slowly pull upwards, separating the adhesive base.
- If the battery fails, warm it up with a hair dryer (no higher than 60°C!).
Warning: If the battery is swelling, don't try to bend or puncture it, it can cause fire, in which case it's better to contact the service.
Step 4: Installation of a new battery
Before installing the new battery:
- Make sure the contacts on the phone and battery are clean (wipe with alcohol if necessary).
- Check that the battery has a thermal shield film.
- Stick the battery to double-sided tape (comes with a new battery).
Step 5: Assembly of the phone
Collect the phone in reverse order:
- Connect the plumes (first the main, then the fingerprint scanner).
- Install the back cover and warm it up with a hair dryer for better gluing.
- Turn the screws (do not pull!).
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The main rule when replacing the battery is not to rush. 80% of damage occurs due to haste when turning off the plumes or removing the battery.
What to do after battery replacement: calibration and testing
After the battery is replaced, the Xiaomi Redmi 4X can show an incorrect charge level or quickly discharge. This is normal - the new battery needs calibration.
- Full discharge: Use the phone before automatically shutting down.
- Charging to 100%: Connect the original RAM and charge to full level (don’t interrupt the process!).
- Re-discharge/charge: Repeat the cycle 2-3 times.
Also check:
- 🔌 Phone Charges Normally (No Overheating or Slow Charging).
- 📊 In battery settings (Settings) → Battery) state is displayed as "Good».
- 🔋 The operating time corresponds to the declared (with moderate use - 1.5-2 days).
If the phone is not switched on after replacement:
- Check if the cables are properly connected.
- Make sure the battery is compatible with the model.
- Connect the charge for 10-15 minutes – sometimes a new battery needs to wake up.
What if your phone doesn’t see a new battery?
Frequent battery replacement errors and how to avoid them
Even experienced users sometimes make mistakes that cause their phones to break down, and here are the most common ones:
| Mistake. | Effects of consequences | How to avoid |
|---|---|---|
| Use of metal tools | Short circuit, battery damage | Use only plastic blades |
| Battery overheating with a hairdryer | Bloating or ignition | Heat no higher than 60°C, do not direct air flow to one area |
| Incorrect connection of plumes | A broken fingerprint scanner or touchscreen | Photograph the location of the plumes before disconnecting |
| Installation of a larger battery capacity | Overheating, rapid degradation, damage to the controller | Choose a battery with a capacity of 4000-4200 mAh |
⚠️ Warning: If after replacing the battery, the phone starts to overheat or discharge quickly, immediately disconnect it and remove the battery.