How to replace the battery Xiaomi Redmi 3S by yourself: a step-by-step guide with a photo

When is the time to change the battery to Redmi 3S

Xiaomi Redmi 3S — One of the most popular budget smartphones 2016 And even with that, it loses its capacity over time, and if your phone runs out in a couple of hours, it shuts down when you're in the middle of a battery. 20-30% If you're charging or you're swelling, you're going to have to think about replacing your battery. 1500 before 3000 But with the tools and patience, you can do everything yourself. 30-40 minute.

In this article, you will find a step-by-step photo instruction, a list of necessary tools, tips for choosing a new battery and unique warnings about typical errors when disassembling Redmi. 3S. We will also discuss how to check the performance of the new battery and avoid problems with the charge sensor.

Before you start, evaluate your strength: if you have never disassembled electronics or are afraid of damaging plumes, you better consult a specialist. But if you are willing to take a risk, read on!

Signs that the Redmi battery 3S need to be replaced

A phone that doesn't always run out quickly means the battery is out of order, and sometimes the problem is the firmware, the background consumption of apps, or a faulty charger, but there are clear signs that the battery is wearing out:

• 🔋 The phone turns off when 20-40% charge and only activated after connection to charging.
• 📉 The battery is discharged for 2-3 with minimal load (for example, in standby mode).
• 🔥 The body of the phone is swollen, the screen or back cover move away from the frame.
• ⚡ Charging is jerky: it quickly gains interest, then “hangs” on one value.
• 🔄 After full charge, the phone shows 100%, through 5 minutes of use, the level drops to 80-70%.

If you're watching at least 2-3 From these signs, the probability of battery wear is close to 100%. Check the exact state of the battery can be using applications like AccuBattery or AIDA64 — They will show the real capacity and degree of wear.

⚠️ Attention: If the phone case is swollen, don't delay replacement! Lithium-ion batteries in this state can ignite when mechanically exposed or overheated. Don't leave the phone unattended on charger and don't expose it to shocks.

What tools will be needed to replace

For disassembly Xiaomi Redmi 3S You'll need a minimum set of tools, most of which can be bought at electronics stores (e.g. Fix Price, 220 Volts) or ordered from AliExpress:

Also prepare a new battery. 3S A battery with characteristics is suitable:

• 🔋 Capacity: 4100 mAh (original) or 4000-4200 mAh (analogues).
• 🔌 Voltage: 3.85 V.
• 🏷️ Marking: BM47 or BL-47Q (Original models from Xiaomi).

Don’t buy batteries from unknown brands with AliExpress at too low a price – they often have an understated real capacity and can damage the phone.

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Before buying a new battery, check the reviews of the seller. Often, under the guise of original batteries, they sell fake containers. 2000-3000 mAh instead of the stated 4100 mAhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh.

Step-by-step: how to disassemble the Redmi 3S and replace the battery

Now, to the process itself, follow the instructions carefully so that you don't damage the plumes or other components of the phone, and do everything on a clean, flat surface (like a tablecloth with a white tablecloth, so you don't lose any small parts).

Turn off the phone and remove it. SIM-memory-card|

Charge your phone at least 20% (to avoid short circuits)|

Prepare a workspace with good lighting |

Take a picture of each step of the dismantling (useful when assembling)|

Disconnect your phone from all cables and accessories

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Step 1: Removing the back cover

Redmi back cover 3S It is glued to the body, so you need to remove it carefully:

1. Heat the hair dryer of the edge of the cover (temperature) ~50-60°C) during 1-2 It'll soften the glue.
2. Insert a plastic spatula into the gap between the lid and the case (start with the lower right corner where the SIM card is located).
3. Carefully drive the shoulder blade along the edge, separating the lid. If resistance is strong, warm up the place again with a hairdryer.

Step 2: Spinning the screws

When you take the lid off, you'll see 10 screws fixing the metal plate. Remember their location -- they're of different lengths. Better place them on a piece of paper in the same order as you would on your phone.

Use the cross screwdriver. PH00 And you can unscrew all the screws. Don't put too much effort into it, because they can be stiff, but they shouldn't break.

Step 3: Disconnecting the plumes

Now you have to disconnect the plumes to get to the battery, and be very careful, they're fragile.

• 📱 Disconnect the battery plume (it is located at the top of the board, under black insulation).
• 🎧 Disconnect the speaker and microphone plume (bottom of the board).
• 📷 Disconnect the camera plume (left side of the board).

To disconnect, use a plastic spatula: gently pull the connector on the side and pull up. Don't pull the wires!

⚠️ Attention: If you accidentally rip the camera plume or speaker, the phone will remain functional, but these functions will stop working!

Step 4: Remove the old battery

Battery at Redmi 3S glued to the body with double-sided tape to remove it:

1. Put a plastic shoulder blade on the battery from either side.
2. Pull it up carefully, separating it from the glue, and if you have strong resistance, put the isopropyl alcohol under the battery, and it will dissolve the glue.
3. Don’t use metal tools – they can puncture the battery!

After removal, inspect the battery: if it is swelling, do not puncture it or throw it in the trash. Lithium-ion batteries should be disposed of at special reception points.

Step 5: Installation of a new battery

Before installing the new battery, clean the place under it of the glue residue with isopropyl alcohol.

1. Stick the new battery to a double-sided tape (comes complete with the battery).
2. Connect the battery plume to the motherboard.
3. Make sure the contacts fit tightly - otherwise the phone won't charge.

Step 6: Build the phone

Collect the phone in reverse order:

1. Connect all the plumes (cameras, speaker, microphone).
2. Then, turn the sleeves (and make sure they are in the same place).
3. Stick the back cover. You can use a new double-sided tape or glue to make it reliable. B-7000.

After assembly, turn on the phone and check:

• 🔋 Charging is stable, without jumps.
• 📷 Camera is working (no artifacts in the photo).
• 🎧 The speaker and microphone are in good condition.

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If the battery doesn't turn on after you change, check the contact density of the battery plume, and 90 percent of the time, that's the problem, not the battery itself.

How to check a new battery after installation

Even if the phone is turned on and shows 100% charge, it does not guarantee that the battery is working.

Method 1: Discharge test

Charge your phone completely, then:

1. Disconnect it from charging and use it in normal mode (calls, instant messengers, the Internet).
2. Take a look at the time it takes for the charge to drop from 100% to 10%.
3. Compare it to the norm: with capacity 4100 The phone should work. 10-12 moderately.

Method 2: Checking with AccuBattery

Install the app from Google Play and analyze:

• 📊 The actual capacity (should be close to the 4000-4100 mAhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh).
• 🔋 Discharge rate (in mA/h).
• 📉 Voltage schedule (should be smooth, without jumps).

If the actual capacity is less than 3500 mAh, the battery is defective or fake.

Method 3: Checking the heating

During charging and heavy use (such as playing), the battery may heat up, but should not be hot. 40-50°C, it's a sign:

• 🔥 Poor quality battery (replacement needed).
• 🔌 Problems with the charging controller (requires diagnosis in the service).

Common Mistakes When Replacing a Battery and How to Avoid Them

Even experienced savvy savvy make mistakes when replacing batteries, here are 5 common problems and ways to prevent them:

If you've already made one of these mistakes, don't panic. In most cases, you can fix the situation:

• 🔧 Replace the broken plume with a new one (it is worth it) 200-500 ₽).
• 🔩 Tangled screws - disassemble the phone and screw them correctly.
• 🔥 Puncture of the battery - immediately take the phone outside, do not turn on, dispose of the battery.

⚠️ Warning: If after the battery is replaced, the phone starts to reboot or turn off on its own, the battery plume or the power controller on the board is likely damaged.

How long will the new battery last and how to extend its life

The life of a lithium-ion battery depends on battery quality and operating conditions.

• 🔋 Xiaomi’s original battery will last 2-3 year-end (400-500 charge-cycle).
• 🔋 Quality analogue (Baseus, Remax) — 1.5-2 year-end (300-400 cycle).
• 🔋 Cheap fake — 6-12 months (100-200 cycle).

To maximize the life of a new battery, follow these rules:

Don't unload the phone before 0% (hold off 20-80%)|

Use an original or certified charger|

Avoid overheating (do not leave your phone in the sun or near the battery)|

Turn off the fast charging if you don’t need it.|

Keep your phone at room temperature (not in the cold or in the heat)

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It is also useful to calibrate the battery once in a while. 2-3 month:

1. Completely discharge the phone before turning off.
2. Charge to 100% without interruption.
3. Disconnect from charging and use until completely discharged.
4. Repeat the cycle 2-3 times.

This will help the power controller to more accurately determine the level of charge.

FAQ: Answers to Frequent Questions