Why Xiaomi Redmi Battery Swells and Why It's Dangerous
Battery bloating is one of the most common problems with Xiaomi Redmi smartphones, especially after 2-3 years of use, and is due to the chemical processes inside lithium-ion (or lithium-polymer) batteries: over time, the electrolyte degrades, releasing gas that expands the battery case. On the Redmi Note 8/9/10, Redmi 9A/9C and other popular models, this is especially often due to heavy use and cheap components in budget series.
The danger of a bloated battery is not limited to a phone breakage. When you swell (more than 2-3 mm), the risk of fire or explosion increases by 5-7 times, especially when charging or overheating. Xiaomi officially recommends replacing the battery at the first sign of deformation, but many users ignore the problem to a critical state. In this article, we will discuss how to self-diagnose bloating on any Redmi - from the old Redmi 4X to the new Redmi Note 12.
7 visual signs of a bloated battery
The first step is to look at the body of the phone, and the bloating of the battery always leads to physical changes that are visible to the naked eye.
- 📱 Convex screen or back cover: if the phone is on the table and swings like a swing, this is a sure sign. 9A, Redmi 8).
- 🔧 There are gaps between the body and the screen: new phones have no gaps. If there is a gap between the display and the frame (you can see in the light), the battery presses from the inside.
- 🔌 Difficult to insert charging cable: bloated battery shifts connector USB-C, because of which the plug is not fixed tightly.
- 🔊 Speaker distortion: On the Redmi Note series, the speakers are located close to the battery. When the membrane is bloated, the sound becomes muffled.
On models with removable back cover (Redmi 5A, Redmi 6), check if the battery bulges when the panel is removed. If the battery looks like a pillow or shows signs of corrosion, this is a critical condition that requires immediate replacement.
Physical Tests: How to Check Without Disassembly
If the bloating is not obvious, use practical diagnostic methods, which are suitable for all Redmi models, including models with a non-removable battery (Redmi Note 11 Pro, Redmi K50).
- Swing test: Put your phone up on a flat surface, press the corners of the case carefully, and if the phone is swinging or springing, the battery is swollen.
- Button check: Press the volume and power buttons. If they become tight or recessed, it may indicate pressure from within.
- Flashlight test: Illuminate the flashlight along the edge of the screen, and if there's a gap between the display and the body, the battery is deformed.
For accuracy, repeat the tests 2-3 times. False positives are possible on phones with curved screens (Redmi K40), but in this case the deformation will be uniform, not local.
Put the phone on the table and check the swing
Press the buttons to assess their progress
Light a flashlight at the joints of the body
Check if the charging cable is tightly in.
Compare it to a new phone (if possible)-->
Programmatic Signs: How a Battery Signals a Problem
Battery bloating affects not only the physical condition of the phone, but also its operation. MIUI:
- 🔋 A sharp drop in capacity: if the phone is discharged for 2-3 during normal use, although previously held the charge for a day.
- ⚡ Incorrect percentage of charge: jumps from 50% before 1% or a sudden shutdown 20-30% charge.
- 🔥 Overheating during charging: if the body is heated to 45-50°C (can be checked in the annex) AIDA64), This is a sign of battery degradation.
- 🛑 Failure to charge: the phone is connected, but charging is jerky or does not go at all.
To check the battery status software, go to Settings → Battery → Battery status. If the capacity has dropped below 70-75% of the original and the phone is less than 2 years old, this is cause for concern. On models with MIUI 13+, the test "Battery Diagnostics" is also available in the Settings → Phone menu.
How to check the battery temperature without apps?
Comparative table: norm vs bloating
To avoid confusing bloating with factory features of the body, compare the characteristics of your Redmi with reference values:
| Sign. | Normal battery | Bloated battery |
|---|---|---|
| Body thickness (mm) | Corresponds to official data (for example, 8.9 mm for Redmi Note 10) | Increased by 1-3 mm, markedly "puzzy". |
| Charging. | Stable, no jumps. | The phone is shut down at 10-30%. |
| Temperature. | Up to 40°C with intensive use | More than 45°C in a simple, hot enclosure |
| Capacity (MIUI) | More than 80% of the initial in 1-2 years | Less than 70%, dramatic drawdowns |
| Physical condition | Body is flat, buttons are clear. | Screen or cover curved, buttons fall |
If 3 or more points on the right-hand side of the phone match your phone, the probability of swelling is 90%, in which case further use is unsafe.
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On Redmi models with NFC (such as the Redmi Note 11 Pro+), bloating can disrupt contactless payment. If the phone stops reading cards, check the battery - the NFC antenna is located next to the battery.
What to do if the battery is swollen: a step-by-step plan
You find the bloating? You use the algorithm.
- Stop using immediately: ❌ Don't charge your phone. ❌ Do not leave it in the sun or in the car. ❌ Don't try to "discharge to zero".
- Extract. SIM-Card and memory card: data can be lost in case of sudden failure of the phone.
- Contact the service: ✅ Xiaomi official service (warranty is maintained if the phone is under 1 year old). ✅ Authorized workshops with original batteries.
⚠️ Warning: Don't settle for "cheap analogues" of batteries! counterfeits are inflated 3 times more often and can ignite.
If there is no replacement
- Keep your phone in a non-combustible container (such as a metal box).
- Do not leave it unattended while charging.
The cost of replacing the battery in the official services Xiaomi:
- Redmi Note 8/9/10: 1 500–2 500 ₽.
- Redmi 9A/9C: 1 200–1 800 ₽.
- Redmi K40/K50: 2 500–3 500 ₽.
Replacement time is 1-2 hours.
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Even if the phone is working "normally," a bloated battery is a ticking time bomb. Lithium-ion batteries ignite when damaged, and bloating is always damage.
Can battery swelling be prevented?
You can't completely avoid battery degradation, but you can slow it down.
- 🔌 Charging: Use Xiaomi’s original power supplies (e.g, MDY-12-ED Redmi Note 11: Avoid "fast" charging from other brands.
- 🌡️ Temperature: Do not operate your phone in temperatures below 0°C or higher than 35°C. Do not leave it in the sun or near heaters.
- 🔄 Charging cycles: try to keep the charge between 20% and 80%. Full discharge (0%) and overcharging (100%) reduce the lifespan.
- 📵 Storage: If the phone is not in use for long, charge it to 50% and turn it off.
On models with MIUI 12+, enable Optimized Charging (Settings → Battery → Battery settings) which automatically limits the charge to 80% if the phone is connected to the network for a long time (for example, at night).
⚠️ Note: Using your phone while charging (especially for games or videos) speeds up battery wear and tear. 30-40%. On Redmi with Snapdragon processors 6xx/7xx (Redmi Note 10 Pro, Redmi K30) Risk of overheating is higher due to high productivity.