Replacement of the battery on Xiaomi Redmi 4X: video review + instruction with a photo

Xiaomi Redmi 4X (codenamed santoni) remains popular even years after its release, thanks to reliability, low price and upgrade capabilities. However, over time, even the best battery loses capacity: the phone begins to run out in a few hours, turn off at 20-30% charge or refuse to turn on altogether. If your Redmi 4X began to “hold” for less than a day, and after diagnosis it turned out that the battery was to blame, replacing it will return the device a second life.

In this article, you will find a step-by-step guide to replacing the battery with all the nuances of the model, a video review of the process from experienced craftsmen, as well as tips for choosing a quality battery. We will discuss what tools you need, how to avoid typical errors (for example, damage to the plume or disconnection of contacts), and what to do if the phone does not turn on after replacing.

If you've never taken a smartphone apart, don't worry: Redmi 4X is a device with moderate disassembly complexity. The key is to be careful and follow the instructions. We've picked up the best video analysis of the process (including where most users make mistakes), and if there are questions left after reading, there's an FAQ at the end of the article that answers the most common problems.

When to change the battery on the Redmi 4X: 5 obvious signs

Before you start the screwdriver, make sure that the battery is the problem, and here are the key symptoms that indicate that you need to replace it:

• 🔋 Phone's running out of power. 3-4 hours with moderate use (social networks, messengers, calls).
• 📉 The percentage of charge “jumps”: for example, from 40% immediately falls to 15%, or after connecting the charging shows 100%, and after a minute – 80%.
• 🔌 The device is switched off when 20-30% charge and not activated without recharging.
• 🔥 The battery is swelling (this can be seen if you carefully press on the back cover - it will "play" or move away at the edges).
• ⚡ The phone overheats during charging or operation (especially in the battery area).

If you have at least 2-3 items on your Redmi 4X list, you probably have a battery that's worn out, and if you want to get a good diagnosis, you can use apps like AccuBattery or CPU-Z that show you the actual battery capacity, for example, if the original Redmi 4X capacity is 4100 mAh, and the app is 2500-3000 mAh, that's a direct signal to replace.

⚠️ Attention: A bloated battery is dangerous! It can damage the screen, the motherboard, or even ignite. If you notice a deformation of the case, don't delay the replacement and don't try to prick the battery.

Another way to test is to test with USB-Put the charger on, and see how much voltage the battery gives off. 4X — 3.7-4.2 V. If the voltage is below 3.5 V even after full charge, the battery is critically worn out.

What battery to choose for Xiaomi Redmi 4X: original vs analogues

The battery quality of the phone is not only the life of the phone, but also the safety of the phone, and there are three types of batteries available for the Redmi 4X:

1. Original (Xiaomi) - manufactured at the plants of ATL or Samsung SDI on behalf of Xiaomi. They are marked BM43 or BM47, capacity 4100 mAh, voltage 3.85 V. Guaranteed compatible with the smartphone power controller.
2. Licensed analogues are manufactured by certified manufacturers (e.g. ZOP Power, Camelion) and have similar characteristics, but may vary slightly in time.
3. No-name batteries are cheap, unlabeled batteries, often with an understated real capacity (3,000-3500 mAh instead of the stated 4100 mAh) that can damage the charging controller or swell in a few months.

Where to buy? Original batteries can be found on AliExpress (from official Xiaomi sellers), in service centers or on sites like Mi-Shop. The price of the question is from 1,200 to 2,500 rubles. Analogs will cost less (600-1000 rubles), but the risk of running into a fake is higher.

Critical: When buying, make sure that the battery is marked BM43 or BM47 (for Redmi 4X), and also a hologram or QR-Counterfeit products are often sold without protective film on contacts or with uneven seams.

💡

Before you buy, ask the seller to send a photo of the battery on both sides, the original one has clear labeling, smooth welds and a protective yellow tape on the contacts.

Preparing for replacement: security tools and measures

To replace the battery with Xiaomi Redmi 4X, you will need:

• 🔧 Plastic blades (2-3 (p) for the rear cover separation.
• 🔨 Cross screwdriver (preferably magnetic) for screws.
• 🧲 Suction (optional, helps to lid the lid).
• 🔥 Hair dryer or thermo-air station for softening glue.
• 🧴 Isopropyl alcohol (for cleaning contacts).
• 📦 New battery (tested, labeled) BM43/BM47).
• 🔌 Tweezers (for careful detachment of plumes).

Important: Work on a clean, well-lit surface; I'd rather cover the table with a soft cloth so you don't scratch the case; if you don't have experience, I'd like you to videotape the process, and that will help me put the phone back together if something goes wrong.

⚠️ Warning: Do not use metal blades to separate the lid - they can damage antenna lines or plumes. Also do not heat the body with an open flame (lighter): this is dangerous for the battery! Before disassembling be sure: Turn off the phone and remove SIM-- A memory card, discharge the battery to 20-30% (It's dangerous to disassemble a bloated battery! Prepare a screw tank (they're small and easily lost), turn off the phone and remove the cards.|Discharge the battery to 20-30%|Prepare tools and workplace|Videotape the process (optional)|Check the new battery for defects--> Step-by-step: how to disassemble Redmi 4X Now, let's get to the process, and follow the instructions carefully, especially when you're unplugging the plumes and retrieving the old battery. 1: Removing the back cover Redmi back panel 4X perimeter-stick. To remove it: Put scotch on the lid (this will help the later to assemble it), heat the edge of the case with a hair dryer (temperature). 60–70°C) during 1-2 Put a plastic blade in the gap between the lid and the body (start at the lower right corner where the antenna lines are). Carefully drive the blade around the perimeter, separating the glue. Do not force - if the lid does not respond, warm up. If the lid is too tightly glued, use a suction cup. Press it against the center of the lid and pull it up while putting it on with a spatula. Step. 2: Disconnection of plumes and batteries After removing the cover you will see: 🔋 Battery (stick to the body). 📶 Antenna plumes (attached to the motherboard). 🔌 Battery connector (shocked by a screw) Act in this order: Unscrew the screw that holds the battery connector (cross screwdriver). Carefully tuck the connector into a plastic blade and unplug it. Unplug the old battery. It's glued to a double-sided tape. Put it on the side of the shoulder blade and slowly pull it up. If the battery is swollen, don't press it! Clear the space under the new battery of glue residues with isopropyl alcohol. Attention to the plumes! On Redmi. 4X There are two thin plumes that go to the antennas. They're easy to tear if you pull the lid too hard. If the plume comes off, you can solder it back, but it requires soldering skills. Step 3: Install a new battery before you install it: 🔍 The new battery has a protective film on the contacts (do not remove it before installation!). 📏 The size and shape of the battery are the same as the old battery. 🔌 Connector clean (wipe with alcohol if necessary) Installation: Stick the new battery onto double-sided tape (both included or purchased separately). Connect the battery connector to the motherboard. Twirl the locking screw (don't pull over!). Make sure the battery is flat, without skewing. Step 4: Build the phone Collect the phone in reverse order: Stick the back cover (use a new glue or double-sided tape). Press the lid around the perimeter for a secure fixation. Turn on the phone and check the charge (should show 100% or close to this: 🔌 Check if the battery connector is tightly seated. 🔋 Make sure the new battery is not swollen and connected properly. 📱 Try pressing the power button for 10-15 seconds (reset). What to do if the phone does not see a new battery? If the battery does not charge after the replacement or shows 0%, two problems are possible: 1. Power controller is defective (requires diagnostics in the service). 2. Bad contact in the connector - check if the contacts on the motherboard are bent. Sometimes it helps to completely discharge (leave the phone off for 12 hours), then connect the charger.Video review: Replacing the Redmi battery 4X For clarity, we have selected the best videos with a review of the process. Pay attention to the moments where the authors focus on typical errors: 1): 🎥 Video link - wizard shows how to separate the lid without damage and what tools to use. 2. Quick battery replacement (without unnecessary details): 🎥 The video link is a short version for those who already have experience disassembling. 3. What to do if the battery is swollen: 🎥 Video link: Case analysis of damaged battery and safety tips. 2x speed to save time, but be sure to pay attention to the: 🛠 How the author holds a plastic shoulder blade (inclination angle!). 🔌 The moment of disconnection of the battery plume (a common mistake is to break it). 🧹 Cleaning contacts with alcohol (this is missed by many beginners). 💡If you're disassembling a smartphone for the first time, be sure to watch the video to the end before you start. Mistakes in the separation of the lid or the removal of the battery can turn into expensive repairs. Frequent errors and how to avoid them Even experienced users sometimes make mistakes when replacing the battery. Here are the most common ones and ways to prevent them: Error Consequences How to avoid Using metal tools Damage to plumes or antennas Use only plastic blades Overheating the body with a hairdryer Melting plastic or bloating the battery Keep a hairdryer at a distance of 10 cm, the temperature is not higher than 70°C Strong press on the bloated battery Breaking the battery, leakage of electrolyte Do not press, but gently smack the shoulder blade from the side Wrong connection of the battery connector Short circuit, failure of the controller Check polarity and contact density A few more nuances: 🔧 Don't lose your screws! 4X They're of different lengths, and if you confuse them, you can damage the motherboard. 🧴 Do not use superglue to fix the lid - then it will be impossible to remove it without damage. 🔋 Don't turn on your phone without a battery (even if it's connected to a charger) - it can burn the power controller. If the battery drains quickly after replacing, check: 📱 Background processes (possibly some application “eats” the charge). 🔄 Battery calibration (discharge phone to 0%, then charge to 100% without interruptions). 🔧 Connector contacts (possibly oxidized or poorly fitting) How much does it cost to replace a battery in vs service on your own If you are not confident in your abilities, you can contact the service center. Here are the approximate prices for 2026: Service Cost (₽) Battery replacement (original) 1 800–2 500 1–2 hours Battery replacement (analogue) 1000–1 500 1 hour Diagnostics of power controller 500–1 000 30 minutes Repair of the plume (if torn off) 1,500–3,000 1–3 days Self-replacement will cost less: 🔋 Battery (original) – 1,200–1,800 ₽. 🛠 Tools (if not) — 300–500 ₽ (once-only). 🧴 Isopropyl alcohol, scotch — 100–200 ₽. If you have the time and desire to understand – self-replacement will save you money. 500–1 000 ₽. But if you're afraid of damaging your phone, you should call the professionals.Please note that official service centers Xiaomi may refuse to put a non-original battery. 💡Savings on the battery can lead to new costs. Cheap analogues often fail through the use of a battery. 3-6 Replacing them in the service will cost more than the original from the beginning. FAQ: Answers to frequent questions ❓ Can I replace the battery with a Redmi? 4X No, that's impossible. The battery at Redmi. 4X It's soldered into the body and glued to the back cover, and the only way to replace it is to completely disassemble the phone. Attempts to “go without disassembling” (for example, connecting an external battery) will damage the power controller. ❓ How long will the new battery last? The life of the battery depends on the type of battery and operating conditions: 🔋 Original battery – 2-3 years (500-600 charging cycles). 🔋 Quality analogue - 1.5-2 years (400-500 cycles). 🔋 Cheap no-name: 6-12 months (200-300 cycles) to extend the life of a battery, avoid: 🔥 Overheating (do not leave your phone in the sun or near heat sources). ⚡ Deep discharge (try not to drop the charge below 10%). 🔌 Use of "left" chargers. ❓ The phone doesn't turn on after you've changed the battery. What to do? There are different reasons. Check in order: Battery contact: Make sure the connector sits tight in the socket. Charging: Connect the phone to charge for 10 to 15 minutes, then try turning it on. Power button: Hold it for 20-30 seconds (sometimes helps with the controller hanging). Trains: If the display plume or antennas break off during disassembly, soldering is required. Power controller: If nothing helps, the controller may have burned (diagnosis is needed in the service). If the phone vibrates or flashes the light but doesn't turn on, the problem is probably the firmware. + Volume down) and reflash the device. ❓ Can you put a larger battery, like 5,000 mAh? Technically possible, but highly discouraged. That's why: 🔧 Physical dimensions: The battery is 5000 mAh thicker and may not fit in the case. 🔌 Power controller: It is designed for 4100 mAh, and the increased load can put it out of order. 🔥 Overheating: A powerful battery can warm up more, especially when charging fast. If you need a larger supply of energy, it is better to buy a powerbank or smartphone with a removable battery. ❓ How do you dispose of an old battery? Batteries are hazardous waste and should not be thrown into the garbage. Here's how to dispose of them properly: 🏙 Reception points: In large cities there are eco-points (for example, Ecotechnologies or MegaFon accepts old batteries). 📱 Service centers: Many workshops accept old batteries for free. 🔋 Special containers: Electronics stores (e.g., Svyaznoy, M. Video) often have recycling boxes. If the battery is inflated, do not throw it into a common container - it can ignite. It is better to take it to a service center where it is properly disposed of.