Xiaomi Redmi Smartphone 7, released 2019 It's still popular with users because of its balanced performance and affordable price, but over time, even the most reliable battery loses capacity: the phone starts to run out in a few hours, turns off when you're in a state of emergency. 20-30% If you're facing these problems, it's time to think about replacing the battery.
In this article, we will discuss how to change your battery to a Redmi 7 without going to the service center, what tools you need, how to disassemble your phone, what to look for when choosing a new battery and how to avoid typical errors. The instructions are suitable for Redmi 7 models (codename: onc) and do not require special skills — enough accuracy and patience.
Before you start repairing, consider your own strength: if you've never taken out a smartphone, it might be better to leave the work to the professionals. 7 no more 30-40 minutes and cost 3-5 Important: Installing the battery incorrectly can cause fire or damage to the board - watch for the polarity and integrity of the plumes!
1. Signs that the battery on the Redmi 7 is time to change
A smartphone battery is a consumable, and even when used carefully, its capacity gradually declines, and here are the key symptoms that indicate the need for replacement:
- 🔋 Phone's running out of power. 2-3 hours with moderate use (social networks, messengers).
- ⚡ The charge is going too fast (from the 0 before 100% post 30-40 minutes) is a sign of loss of capacity.
- 📉 The percentage of charge "jumps" (for example, with a 50% straight away 20%) or the phone is turned off when 15-30%.
- 🔥 The body heats up in the battery area even without loading.
- 🛑 The device does not turn on without a charge connection, although the indicator shows the residual charge.
If at least 2-3 You know the item on the list, and you probably know it's worn out, and you can check it with apps like AccuBattery (available on Google Play), and it'll show you the actual battery capacity, if it's smaller. 70% factory-wise (3900–4000 MAAh for Redmi 7), It's time to think about replacing.
⚠️ Warning: if the phone is swollen (the body is deformed, the screen "steps" from the frame) - immediately turn it off and do not try to disassemble! The billowing battery may ignite.
Also, it is worth considering that rapid discharge can be associated with software problems (background processes, viruses) or hardware malfunctions (damaged charging plume, oxidized contacts).
- 🔄 Reset the settings to factory (Settings) → The phone. → Resetting settings).
- 🛠️ Switching the phone to the latest version MIUI (through settings → Updating the system).
- 🔍 Check energy consumption in Settings → Battery – maybe it’s a specific application that’s to blame.
2. Which battery to choose for Xiaomi Redmi 7
The quality of the battery is not only the life of the phone, but also the safety of the phone, and cheap fakes can swell, overheat, or even ignite.
| Parameter | Recommended value | Explanation |
|---|---|---|
| Capacity | 3900–4,000 mAh | Redmi 7 factory capacity - 4000 mAh. Do not take batteries with overestimated performance (5000)+ mAh is a hoax. |
| Type | Li-Polymer (Li-Po) | This is the type used in Redmi 7. Lithium (Li-Ion) will not work. |
| Tension. | 3.8–4.4 V | It should match the original. Check the labeling on the battery. |
| Manufacturer | ATL, SDI, Lishen | These are trusted vendors for Xiaomi. avoid no-name brands. |
| Compatibility | Redmi 7 (onc) | Check the model code (onc) – batteries for Redmi Note 7 or other devices will not work! |
Where to buy:
- 🛒 Xiaomi’s official stores (e.g. mi.com) – the original battery warranty, but the price is higher.
- 🌍 Sites like AliExpress, Amazon or eBay – look for sellers with a rating of 98%+ Compatibility with Redmi 7.
- 🔧 Local phone parts stores – ask for a quality certificate and check the battery on site (check contacts, case for no bloating).
The average price of a quality battery for Redmi 7 is from 800 to 1500 rubles. Original batteries from Xiaomi cost more (1500-2500 rubles), but last longer. Be careful with fakes: they are often issued as the “original” at a low price.
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Before buying, check the battery serial number on the manufacturer's website (if indicated), and ask the seller to send a photo of the marking - it must match the original one (for example, the first one, HB4161H4ECW For some Redmi 7 games).
3. Battery replacement tools
To disassemble the Redmi 7 and replace the battery, you will need:
Get a new battery (see section above)|Buy or rent tools (list below)|Make a backup of the data (Settings) → Additionally. → Backup)|Charge your phone at least 30% (in case you need testing)|Prepare a clean, well-lit workplace-->
- 🔧 Plastic blades/mediators (2-3 (a) - for separation of the back cover and the battery.
- ⚙️ Screwdriver kit: cross-haired (PH00) and five-pointed (Pentalobe) P2) Xiaomi screws.
- 🔥 Dryer or thermo-air station - for softening the glue (temperature 60-80)°C).
- 🧲 Magnetic mat or tray - so as not to lose screws.
- 📏 Suction (optional) - helps to suction the lid.
- 🧴 Isopropyl alcohol (90%+) — Cleaning contacts and removing glue residues.
- 🔌 Tweezers - for careful disconnection of plumes.
- 🛡️ Gloves and safety glasses in case the battery is damaged.
Where to buy tools:
- Smartphone repair kits are sold on AliExpress, Ozon or Wildberries (price from 300 to 1000 rubles).
- Individual tools (such as a five-pointed screwdriver) can be found in electronics stores.
- If you don’t plan to do repairs regularly, rent tools (there are such services in major cities).
⚠️ Warning: Do not use metal blades or knives to separate the lid - they can damage the body or plumes! Also avoid overheating with a hairdryer: if the temperature exceeds 90°C, you can melt plastic or damage the screen.
Step-by-step: how to disassemble the Redmi 7 and replace the battery
Now, let's get to the process. Follow the instructions carefully and take your time, because most battery replacement errors are due to rush.
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Before disassembling, be sure to turn off the phone and remove it. SIM-It is also recommended to wear an antistatic bracelet (or at least touch a grounded metal object) to avoid static discharge.
Step 1: Removing the back cover
1. Heat the edge of the back cover (around the perimeter) with a hair dryer for 1-2 minutes. This will soften the glue.
2. Insert a plastic blade into the gap between the lid and the body (start at the bottom edge where the charging connector is). Carefully drive the blade along the edge, separating the lid.
3. If the lid doesn't respond, reheat the problem area. Don't put too much effort into it, you can break the latches!
4. After removing the lid, put it aside. Be careful: it has a fingerprint scanner glued to it (if you have one in your model).
Step 2: Battery disconnection
1. Unscrew 10 screws that fix the metal plate over the battery (use a five-pointed screwdriver). P2).
2. Carefully remove the plate and put it together with the screws (they are of different lengths - remember where you were!).
3. Unplug the battery plume with a plastic blade. Don't pull the wires! Put the connector on the side.
4. Check the voltage at the contacts of the battery multimeter (should be 3.7-4.2 V). If the voltage is below 3 V, the battery is very discharged - it can not be charged in the usual way (need a special charger for Li-Po batteries).
Step 3: Remove the old battery
1. Put a plastic blade on the battery from any end, and underneath it you'll see strips of glue.
2 Pull the strips slowly and evenly. If they break, pour the isopropyl alcohol under the battery, it will dissolve the glue.
3. Don't rot or puncture the battery! If it swells, be especially careful.
4.After removing the battery, clean the seat of glue residues with alcohol and a napkin.
Step 4: Installation of a new battery
1. Check polarity: red wire - plus (+), The black is minus (-). The phone and battery must match the markings.
2. glue the new battery to double-sided scotch (usually included) or use the original glue (sold separately).
3. Connect the battery plume to the connector on the board. Make sure it sits down to the end (should be a slight click).
4. Install the metal plate back and twist the screws (don't pull!).
Step 5: Assembly of the phone
1. Check the new battery: connect the charger and make sure the phone turns on and correctly determines the charge level.
2. glue the back cover. Use the original glue (e.g, B-7000) Or double-sided scotch. Heat the lid with a hair dryer for better fixation.
3. Twistle the screws on the bottom of the phone (if any).
4. Turn on the phone and check all the functions: charging, sensor, camera, speakers.
What if the phone doesn’t turn on after the battery is replaced?
5. Common Mistakes and How to Avoid Them
Even if you change the battery carefully, you can make mistakes that will cause your phone to fail, and here are the most common ones and ways to prevent them:
- 🔌 Damage to the battery plume occurs when you disconnect sloppy. Always stick a plastic blade on the side of the connector instead of pulling the wires.
- 🔥 Overheating the battery with a hairdryer - can cause bloating or fire. Keep the hairdryer at a distance of 5-10 cm and do not heat one point longer than 10 seconds.
- 🔄 The wrong polarity, if you confuse it + And -- the phone won't turn on, and the battery could get damaged!
- 🛠️ Loss of screws or retraction of screws are screws in Redmi 7 of different lengths. Store them in a magnetic tray and don't twist too much.
- 📱 Damage to flexible plumes (such as screen or power button) – work gently, do not press on the middle of the phone.
If you have changed the battery phone:
- 🔋 No charge – check the charging plume and battery contacts.
- 📉 Shuts off at 10-20% – it’s possible that a new battery needs calibration (discharge the phone to zero, then charge to 100% without interruptions).
- 🔥 Overheating – this could be a sign of poor quality battery or damage to the charging controller.
⚠️ Attention: if after the battery change, the phone starts to arbitrarily restart or shut down, most likely the problem is the contact between the battery and the board. Try reconnecting the plume or cleaning the contacts with alcohol. If this does not help, contact the service (possibly damaged fee).
Calibration of the new battery
To make a new battery work as efficiently as possible, you need to run it right. Here's how to do it:
- Full discharge: Use your phone before automatically turning off (do not recharge!).
- Full Charging: Connect your phone to the original charger and charge up to 100% without interrupting the process (preferably off).
- Repeat the cycle 2-3 times, which will help the battery controller to determine the level of charge more accurately.
It is also recommended that:
- 🔋 Avoid full discharge in everyday use (it is optimal to keep a charge between 20% and 80%).
- ⚡ Do not use your phone while charging (especially for games or videos) – this reduces battery life.
- 🌡️ Avoid overheating (do not leave your phone in the sun or near heat sources).
Modern Li-Po batteries do not have a memory effect, so frequent recharging does not harm capacity. However, deep discharges (below 5%) and overcharging (over 95%) accelerate degradation.
7. Alternatives: Service center vs. self-replacement
If you're not confident, you can trust a battery replacement to a professional, and here's a comparison of the two approaches:
| Criteria | Self-sustaining replacement | Service centre |
|---|---|---|
| Cost | 800–1500 ₽ (battery) + 300–500 ₽ (tool) | 1500–3000 ₽ (depending on the service) |
| Time. | 30-60 minutes | 1-3 days (including the queue) |
| Guarantee | Battery only (if purchased from the official seller) | 1-6 months to work and spare parts |
| Risks. | Damage to the phone during careless disassembly | Minimum (if the service is verified) |
| Battery quality | Depends on your choice (the risk of getting a fake) | Usually original or certified analogue |
When to choose a service:
- 🛠️ You don’t have the time or tools to do your own repairs.
- 🔥 Battery swollen or damaged – it is dangerous for self-replacement.
- 📱 Phone warranty (although the battery is usually considered an expending phone and not covered by warranty).
When you can change it yourself:
- 💰 Want to save (the difference in price can reach 1000-1500 rubles).
- 🛠️ You have experience disassembling equipment (for example, you have already changed the screen or cleaned your laptop).
- 🔋 You have a good battery and are willing to take a risk.
If you do decide to use the service, choose a proven workshop.
- 📝 Availability of reviews (for example, on Yandex.Maps or 2GIS).
- 🛡️ Work guarantee (minimum 1 month).
- 💬 Ability to be present during repairs (to make sure the original battery is installed).