Replacing the battery with Xiaomi Redmi Note 7: a complete guide from battery selection to assembly

Why the Redmi Note 7 battery fails and when to change it

Xiaomi Redmi Note Smartphone 7, released 2019 year, equipped with a non-removable battery capacity 4000 CAH: Despite the stated resource in 500-800 Charging cycles, the actual battery life rarely exceeds 2-3 The main signs of wear and tear: the phone discharges in a few hours, turns off when 20-30% charge, overheats during charging or loading tasks.

Manufacturer does not provide for an official replacement of the battery in service centers – Redmi Note 7 Xiaomi Care is not included in the program, and replacing the battery automatically cancels the warranty (if it is still valid). 3-5 It is cheaper than buying a new phone and does not require special skills.

Before starting the disassembly, check the actual wear of the battery:

• 📱 Install the AccuBattery app (Android) and analyze the battery health data. A value below 80% is a direct signal to replace.
• ⚡ Connect the phone to charge and watch the charge rate. 0% before 100% more 3-4 hours - the battery degraded.
• 🔥 Feel the case during heavy use (games, video) Local heating at the bottom is a sign of swelling of the battery cells.

Which battery to choose for Redmi Note 7: original vs analogues

The original battery for the Redmi Note 7 has an articular MB-J10B (or DM-BH01 However, after 2021, Xiaomi officially stopped supplying spare parts for this model, so the market is dominated by analogues from third-party manufacturers. Even the “original” batteries sold on AliExpress or local services are often repackaged.

Criteria for choosing a quality battery:

• 🔋 Capacity: not less 3900-4000 mAh Batteries with declared "4500 MACh" - a fake with an understated real capacity.
• 🏭 Manufacturer: proven brands — ZOP Power, Shenzhen DNK, Sunwoda (supplier for Xiaomi) Avoid no-name batteries without labeling.
• 📦 Set: the set must have a double-sided tape for fixation and insulation film (to avoid short circuits).
• 💰 Price: A quality analogue is worth 800-1500 Batteries are cheaper 600 RUB - High risk of marriage.

⚠️ Warning: Buy batteries only from trusted sellers with ratings above 95% and reviews over 6 months old.New accounts on marketplaces often sell defective batteries that can swell after a week of use.

Replacement tools: what you need and where to buy

To disassemble the Redmi Note 7 and replace the battery, you need a specialized tool, and using improvised tools (knives, screwdrivers of the wrong size) will damage the body or plumes.

• 🔧 Spudger, to separate the body clips, it's best to have a set of 3-5 plentiful.
• 🔨 Cross screwdriver PH00 — For the back cover screws. PH0 It is not suitable because of the risk of tearing the slats.
• 🧲 Magnetic mat or organizer – to avoid losing small screws (there are 15 of them)+ piece).
• 🔥 A hair dryer or a thermo-air station to soften the glue under the battery. At least 1,000 watts of power.
• 🛠️ Suction cup – helps lift the back cover after heating.
• 🧴 Isopropyl alcohol (90%+) — to remove glue residues. Acetone or solvent cannot be used!

Where to buy the tool:

• Smartphone repair kits on AliExpress (price) 300-800 ₽, delivery 2-4 weekdays).
• Radio parts stores ("Chip and Deep", "Platan") - screwdrivers and shoulder blades piece by piece.
• Service centers – sometimes sell the tool “with hands” (ask the masters).

⚠️ Warning: Do not use metal blades to smack the battery, they can puncture the battery body and cause a short circuit!

Step-by-step: how to disassemble the Redmi Note 7 and replace the battery

The replacement process takes 40-90 The rule is to take your time and follow the instructions strictly in steps. Sequence disruption can damage the display plume or motherboard.

Step 1. Disconnect and heat the case

Turn off the phone and put it down with the screen. Use a dryer at medium power (temperature) 60-70°C) and warm the back cover around the perimeter for a period of time 2-3 This will soften the glue that holds the lid. Don't overheat, the plastic can deform!

Suction the top of the lid (near the camera) and gently pull up. Once the slit appears, insert a plastic blade and slowly lead it along the body, disconnecting the clips, 12 of them - 3 on each side and 3 on top/bottom.

Step 2: Unscrew screws and remove the lid

After removing the cover, you will see 15 screws of different lengths:

• 🔹 4 long screws (near the motherboard).
• 🔹 6 medium (on edges).
• 🔹 5 short (near the camera and charging connector).

Take a picture of them or group them on a magnetic mat. Use a screwdriver. PH00 — slithering.

Step 3: Disconnection of plumes and batteries

Carefully disconnect the plumes in this order:

1. Battery (connector with the inscription) BATT).
2. The display plume (the widest, right).
3. Camera plume (thin, left).
4. The power button plume (small, top).

Use a plastic spatula with the connectors on the side. Don't pull the wires!

Step 4: Remove the old battery

The battery is glued to the body with double-sided tape, and grab it by a special black film (traction tongue) at the bottom. If there is no film, gently slide the battery with a spatula from any angle and pull it up. When resisting, warm up with a hairdryer (no more than 50).°C!).

Remove the glue residues with isopropyl alcohol. Don't use acetone, it corrodes plastic!

Step 5: Installation of a new battery

Before installation, check:

• 🔋 The battery should have an insulating film (if not, stick it yourself).
• 📏 The battery connector must match the connector on the board (20 contacts).
• 🧴 On the case, stick a new double-sided tape (goes with battery).

Connect the battery to the connector and gently press it to the body, starting from the bottom.

Step 6: Assembly of the phone

Collect the phone in reverse order:

1. Connect all the plumes (start with the display).
2. Twisting the screws, starting with the short ones.
3. Press the back cover until the clip clicks.
4. Warm up the hair dryer of the edge of the cover (temperature 50)°C) for better glue fixation.

1. Connecting the display plume (frequent error - not fully inserted connector).

2. Battery contact (sometimes a light press on the body in the battery area helps).

3. screws - an excess or missing screw can cause a short circuit.-->

Frequent Mistakes and How to Avoid Them

Even with a careful battery change, beginners make mistakes that cause their phone to break down.

Another common problem is that the phone doesn't turn on after assembly, and 90 percent of the time, it's because of:

• 🔌 Unconnected display plume (check the connector on the board).
• 🔋 Incorrectly installed battery (connector should sit tightly).
• 🔧 Excess screw under the motherboard (causes short circuit).

⚠️ Warning: If after replacing the battery, the phone turns on but discharges quickly (e.g., 100% to 0% in 1 hour), chances are you have installed a defective battery.

Calibration of the new battery: why it matters

After the battery is replaced, it needs to be calibrated so that the charge controller correctly determines the level of charge. Without calibration, the phone can show the wrong percentage (for example, 100% at a real 80%) or suddenly turn off.

Calibration instructions:

1. Charge your phone to 100% and keep charging for another 1 hour.
2. Turn off charging and use the phone until it is completely discharged (until it turns off).
3. Connect the charging and charge up to 100% without interruptions.
4. Repeat the discharge / charge cycle 2-3 times.

To speed up the process, you can use the Battery Calibration application (root rights are required) or manually reset calibration data via the engineering menu:

##4636## → Battery information → Erase learned stats

This method does not work on all firmware MIUI, But it's worth a try.

💡

Calibration is especially important for analog batteries, as their charge controllers are often incompatible with the original Xiaomi firmware. Without calibration, the new battery can last 2 times less.

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

The battery life depends on 3 factors:

• 🔋 Battery quality: original or certified analogues (ZOP, Sunwoda serve 2-3 year, no-name — 6-12 months.
• 📱 Intensity of use: during active games / video, the battery degrades 1.5 times faster.
• ⚡ Charging mode: Constant charging to 100% and discharging to 0% kill battery in 1.5 years.

Recommendations for extension of service:

• 🔌 Keep the charge in range. 20-80%. Use apps like AccuBattery to control.
• 🌡️ Avoid overheating (do not play games in the sun, do not use your phone while charging).
• 🔄 Once every 3 months, perform a full discharge/charging cycle for calibration.
• 🛌 Don’t leave your phone on charge overnight – turn off power after 100.

Average life of a quality battery when used carefully:

• 📅 2 year-long preservation 85-90% capacity.
• 📅 3 year-end — 70-80% Capacity (notably reduced working time).
• 📅 4+ Less than 60% of the year (replacement required).

FAQ: Answers to Frequent Questions