Xiaomi Redmi 4X for battery replacement: detailed instructions with photos and tips

Xiaomi Redmi 4X — One of the most popular budget smartphones 2017 for years, but even through 3-4 The battery begins to “die”: the phone discharges in a few hours, turns off when 20-30% It's not going to be charged or even turned on. 1,5-3 You can save thousands of rubles, but you can do it yourself if you want. 4X with a photo, a list of necessary tools, tips for choosing a battery and important nuances that even experienced masters miss.

The main challenge in disassembling the Redmi 4X is the adhesive fixation of the back cover and the brittle plume of the fingerprint scanner. If you do not act carefully, you can damage not only the body, but also the motherboard, we will tell you how to avoid typical errors, what tools you really need (and what you can do without), and give recommendations for calibrating the new battery after installation.

This article is for beginners and those who have had experience in repairing equipment, and if you've never taken a smartphone apart, don't worry: the Redmi 4X is a medium-sized model, and if you take the right approach, you're not too quick to break anything.

Preparation for analysis: tools and materials

Before you start to disassemble, make sure you have everything you need. The minimum battery replacement toolkit in the Xiaomi Redmi 4X includes:

• 🔧 Plastic blade (or mediator) - to separate the back cover. Metal tools can not be used: they will scratch the body and can damage the plumes.
• 🔨 The screwdriver. PH00 (It's magnetic. It's not a screwdriver, it's a screwdriver in Redmi. 4X Very small and easily "slime».
• 🧲 Suction cup (optional) - helps to lid if the glue is too strong, can be replaced with a wide plastic card.
• 🔋 New battery - original (article) MBJ402450) or a qualitative analogue (for example, from Baseus or Remax).
• 🧴 Isopropyl alcohol (90%+) — to remove glue residues. Acetone or solvent cannot be used!
• 📦 The screw container is designed to keep the small parts from getting lost, and the plastic bottle lid with the painted compartments is fine.

Important: the battery for the Redmi 4X should have a capacity of 4100 mAh and a voltage of 3.85 V. Batteries with other parameters (for example, 4000 mAh) may incorrectly display the level of charge or fail faster.

We also recommend that you prepare:

• 📸 Smartphone to capture the process – take pictures of each step so as not to confuse the order of the assembly.
• 🧤 Antistatic bracelet (optional) – protects the board from static electricity.
• 🔦 Lantern or table lamp – the lighting should be bright so as not to miss small details.

⚠️ Warning: If you've never worked with electronics, practice on an unnecessary device (like an old charger or remote). 4X Fingerprint scanner plume is glued to the lid - it is easy to tear when sloppy opening.

Battery selection: original vs analogues

The original battery for Xiaomi Redmi 4X (article MBJ402450) costs about 1500-2000 rubles, but it is difficult to find it on sale - Xiaomi has long since withdrawn the model from production. In most cases, users choose analogues from third-party manufacturers.

We recommend paying attention to batteries from the following brands:

• 🔋 Baseus is a reliable Chinese manufacturer, batteries are close to the original in characteristics.
• 🔋 Remax - budget option with a good price/quality ratio.
• 🔋 ZMI (Xiaomi sub-brand – if you find it on sale, it’s the best choice after the original.

Avoid batteries without labeling, with unclear articles or too low a price (less than 600 rubles), which are often understated and can swell in a few months.

⚠️ Attention: Check the seller's reviews before buying. AliExpress and Wildberries often sell fakes under the Baseus or Remax brands. Focus on photos of real buyers and ratings above 4.7.

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Before installing a new battery, charge it to 50-60%, which will help to avoid sudden power surges when you first turn on the phone.

Step-by-step analysis Xiaomi Redmi 4X

Now, let's get to the process itself. Follow the instructions in strict order, and skipping the steps can damage your phone.

Step 1: Turn off and prepare the phone

Before the trial:

1. Turn off the Redmi 4X with a long press on the power button.
2. Extract. SIM-cards and memory cards (if installed).
3. Remove the cover (if any).
4. Warm up the back cover with a hair dryer (50–60°C) for 2-3 minutes. This will soften the glue and make it easier to open.

Step 2: Removal of the back cover

This is the most important stage.

1. Insert a plastic blade into the gap between the lid and the body at the headphone jack.
2. Slowly drive the shoulder blade along the edge, separating the lid, and if you feel resistance, don't push harder, but warm up the place with a hairdryer again.
3. When the lid starts to move, don’t remove it completely: it is connected to the fingerprint scanner with a thin plume!
4. Carefully lift the cover and disconnect the scanner plume (it is attached with a small connector).

Step 3: Shutting off the battery

Before touching the motherboard, be sure to turn off the battery:

1. Find a small black connector with the inscription BATTERY (usually located at the top).
2. Carefully put a plastic spatula on it and unplug it.
3. Wait 1-2 minutes – this will discharge the residual current in the capacitors.

Battery's off.|All metal jewelry (rings, bracelets) removed)|The working surface is clean and dry|Tools undamaged-->

Step 4: Remove the old battery

The battery in the Redmi 4X is glued to the body to remove it.

1. Apply a few drops of isopropyl alcohol under the battery (between it and the body).
2. Wait 1-2 minutes - the alcohol will dissolve the glue.
3. Carefully tuck the battery into the side of the plastic shoulder blade and slowly pull it up. Don't rot it!
4. If the battery fails, add more alcohol and try again.

Extract the bloated batteries with extreme care: they can burst when deformed. If the battery is too swelled, don't use alcohol, it can leak in and damage the board.

Step 5: Installation of a new battery

Before installing the new battery:

1. Clean the seat of glue residues (use alcohol and cotton swab).
2. Make sure that the contacts of the new battery do not have protective film.
3. Stick the battery to double-sided tape (comes with it) or use B-7000 glue.
4. Connect the battery connector to the board.

Step 6: Build the phone

Collect the phone in reverse order:

1. Connect the fingerprint scanner plume to the connector on the board.
2. Install the back cover, starting at the bottom (where the charging connector is).
3. So, turn all the stains (not to be worn).
4. Turn on your phone and check your workability.

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Never turn on your phone with the battery turned off – it could burn the motherboard!

Calibration of the new battery

After you change the battery, you need to calibrate it so that the phone displays its charge level correctly.

1. Charge your phone to 100% (use the original adapter).
2. Turn off charging and let the phone run until it automatically shuts down (don’t turn it on manually!).
3. Connect the charging and charge up to 100% without interruptions.
4. Repeat the discharge / charge cycle 2 more times.

This procedure will help the power controller to “learn” how to correctly determine the capacity of the new battery. If after calibration the phone still shows an incorrect charge (for example, jumps from 50% to 20%), it may be a problem in the controller on the board, in which case you need a diagnosis in the service.

Common Mistakes and How to Avoid Them

Even experienced craftsmen sometimes make mistakes when parsing the Redmi 4X, and here are the most common ones and ways to prevent them:

• 🔧 The damage to the fingerprint scanner plume occurs when you sharply tear the lid off. Solution: warm up the dryer and separate the lid slowly, starting at the top corner.
• 🔋 Short circuit when you plug in the battery -- if you tweezers both the plus and the minus of the battery -- Solution: Turn off the battery before any charge charge.
• 📱 Loss of screws at Redmi 4X Solution: spread them out into separate containers or photograph the location.
• 🔥 Overheating of the board when soldering — if you try to solder the battery with a soldering iron. Solution: use only alcohol or a special glue solvent.

Another common problem is that the phone can’t see. SIM-This happens if you don't put the card tray in, or you damage the contacts, and make sure that the tray goes into the case effortlessly and doesn't hang around.

The cost of replacing the battery in the service vs independently

If you're in doubt, you can go to the service center, and here's the price tag for 2026.

It's cheaper to replace yourself, but only if you don't damage your phone in the process. For example, replacing a fingerprint scanner plume can cost up to 2,000 rubles, and repairing the board after short circuit can cost up to 5,000 rubles. If you've never taken your phones apart, consider the risks: will you save?

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Replacing the battery on your own in the Redmi 4X is justified if you are confident in your skills or are prepared for the potential cost of error repair.

FAQ: Frequent questions about battery replacement in Redmi 4X