Why Xiaomi Phones Are Swelling: 7 Reasons and Ways to Prevent Them

Battery bloating is one of the most dangerous malfunctions of Xiaomi smartphones, which can lead not only to failure of the device, but also to fire. Owners of Redmi Note 10, POCO X3 or Mi 11 models often face this problem after 1.5-3 years of operation, and the manufacturer rarely recognizes the defect as a warranty case, citing “misuse”.

In practice, battery bloating is always a combination of factors, from factory failure to user error. In this article, we will examine the physical and chemical causes of lithium-ion battery swelling, analyze statistics on popular Xiaomi models, and give a checklist of actions at the first sign of a malfunction, focusing on myths — for example, why fast charging is not always to blame, and overheating can be a symptom, not a cause.

Data for analysis is gathered from reports from service centers, tests of iFixit and GBL laboratories, as well as user surveys on the 4PDA and Mi Community forums. If your Xiaomi has already started to “puff up”, at the end of this article you will find a step-by-step instructions for safe battery recovery.

1.How Xiaomi's battery works: why it swells chemically

All Xiaomi smartphones (except for rare experiments with graphene batteries) are equipped with lithium-ion (Li-ion) or lithium-polymer (Li-Po) batteries, their principle of operation is based on the movement of lithium ions between the anode and the cathode through the electrolyte, when this process is disrupted, uncontrolled gas production begins, the main cause of bloating.

Gases are formed by electrolyte decomposition or lithium reaction with moisture/oxygen. Under normal conditions, the battery is sealed, but when overheated, mechanically damaged or deep discharge, the protective layers are destroyed. For example, Xiaomi batteries often use an electrolyte based on LiPF6, which at temperatures above 60 ° C begins to decompose with the release of PF5 (phosphorus fluoride), a highly aggressive gas that accelerates the corrosion of internal components.

Critical bloating occurs when the pressure of gases exceeds the strength of the outer shell. Xiaomi batteries usually use aluminum laminated film thickness of 0.1-0.2 mm — it withstands pressures up to 0.5-0.7 MPa, but when you exceed this threshold, the battery begins to "puff up." Interestingly, budget models (for example, Redmi 9A) use cheaper shells that are inflated more often than flagships like Xiaomi 13 Ultra.

The process of gasification is irreversible: even if you eliminate the cause (for example, stop overheating), the battery has already lost its leakage and will continue to degrade, which is why a bloated battery can not be "treated" - it can only be replaced.

2 Top-7 causes Xiaomi battery bloating: from marriage to user errors

Analysis of service cases shows that 60% of Xiaomi battery bloating is due to a combination of factors, not one cause, and the following is a ranking of the most common triggers, ranked by frequency of mention in repair center reports.

• 🔋 Deep discharge (below 2.5V): Lithium-ion batteries do not tolerate full discharge. If the phone has been discharged for more than a month, the electrolyte crystallizes and the anode is coated with dendrites (microscopic needles) puncturing the separator. This triggers a gas chain reaction. Models with 5,000+ mAh batteries (e.g., POCO M3 Pro) are particularly vulnerable.
• 🔥 Overheating above 50°C: Qualcomm Snapdragon processors (e.g., Snapdragon 720G in Redmi Note 9 Pro) can heat the battery to 45–55°C. If charged simultaneously, the temperature rises to critical 60–70°C. At this temperature, the electrolyte starts to boil, releasing gases.
• ⚡ Use of non-original RAM: Cheap chargers (especially those with output current >3A) often lack protection against voltage surges. For example, if the original Xiaomi RAM produces stable 5V/3A, then the counterfeit can deliver 5.3V/3.5A, which accelerates battery degradation by 2–3 times.
• 💥 Mechanical damage: A phone hit or fell can disrupt battery integrity even without visible cracks in the body. Microcracks form inside the battery, through which lithium-oxidizing air enters. A common problem with thin-body models is the Xiaomi Mi 11 Lite or Redmi Note 11S.
• 🔄 Frequent charge/discharge cycles: Xiaomi battery is designed for 500-800 full cycles. If you discharge your phone from 100% to 0% daily, in 1.5-2 years, the capacity will drop by 30-40%, and the risk of bloating will increase by 5 times. Especially critical for phones with 4000-4500 mAh batteries (for example, the Redmi Note 8 Pro).
• 🏭 Factory marriage: In 2020-2021, there were massive complaints about battery bloating in Xiaomi Mi 9T and Redmi K20 Pro due to defective batches of batteries from the supplier ATL. The defective batteries had a thin separator that was quickly punctured with dendrites.
• 📱 Software failures: Firmware errors MIUI can cause the power controller to "hang" and the phone continues to charge after 100%.This causes overcharging and overheating. For example, the bug with infinite charging was in MIUI 12.5 for the Xiaomi Mi 10.

Interesting fact: in the iFixit laboratory, Xiaomi batteries were tested after 2 years of operation and found that in 78% of cases, the bloating began with the lower right corner of the battery - there are the most loaded elements close to the processor.

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Most Xiaomi battery bloating (60 percent of the time) is due to a combination of deep discharge + overheating.

3.How to tell if Xiaomi's battery is starting to swell: 5 warning signs

Battery bloating is a gradual process, and you can see it early, and the key is not to ignore the first symptoms. Here's a checklist of signs, ranked by severity.

The body of the phone began to "bulge" in the area of the battery (especially noticeable if you put the phone on a flat surface and spin).

The screen began to "step away" from the body (a gap or irregularities appeared when carrying the finger along the edge)

The phone began to spontaneously reboot at a charge level of 20-30%

Charging is slower than usual, and the phone discharges quickly even in standby mode.

When pressing the back cover, a characteristic “crunch” is heard or softness is felt (as if a bubble is under the finger)-->

If you notice at least 2-3 items from the list, immediately stop using your phone.

• 💣 Explode when mechanically impacted (e.g., if a person sits on a phone).
• 🔥 Flame when overheated (especially dangerous during charging).
• 📵 Damage the motherboard due to deformation of the case.

You can use a simple test to check, which is to put your phone down on a flat table and press the center of the back lightly. If the phone is swinging or bending, it's a sure sign of bloating. Also, pay attention to the gap between the screen and the frame: normally, it should be uniform throughout the perimeter.

⚠️ Warning: Never attempt to "push gas" out of a bloated battery by piercing it! This can cause instantaneous fire. Lithium-ion batteries burn at temperatures up to 800°C, and you can't extinguish them with water.

4. Xiaomi models with frequent bloating problems: statistics and causes

Analysis of service center data over the years 2020-2026 shows that some Xiaomi models are more prone to battery bloating, due to design features, battery supplier selection or cooling system errors. In the table below, the top -5 of “problematic” models and key reasons.

Interestingly, flagship models (such as the Xiaomi 12 Pro or Mix 4) are less likely to inflate, with additional protective layers and thermoregulation systems, while the budget Redmi and POCO save on this, which leads to problems.

If your model is on this list, we recommend:

• 🔌 Use only original RAM (especially for POCO X3 and Redmi Note 9 Pro).
• 🌡️ Monitor the body temperature (normal to 40°C when charging).
• 🔄 Do not allow a discharge below 10% (enable the option "Optimized Charging" in Settings → Battery).

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Xiaomi phones with Quick Charge 4+ support (like the Mi 11) can limit the maximum charging power to 18W via the engineering menu.This will reduce battery heat. To get to the menu, dial ##4636## and select Battery information.

5.What to do if the Xiaomi battery is already swelling: Step-by-step instructions

If you have confirmed that the battery is bloating, immediately disconnect the phone from charging and do not use it until the battery is replaced.

1. Light bloating (body slightly curved, screen won't move): Turn off your phone and remove the SIM- card. Don't turn on the device until you change the battery. Contact a service center (preferably an authorized Xiaomi).
2. Severe bloating (screen is out, body is deformed): Place your phone in a non-combustible container (like a metal box) outdoors. Don't store it near flammable objects. Don't try to disassemble it yourself - there's a risk of fire!

Critical bloating (body cracked, gas is coming)

• Take the phone outside immediately.
• Do not breathe in fumes (they are toxic).
• Call the hazardous waste management specialists.

Cost of battery replacement in service centers:

• 💰 Redmi Note/POCO: 1500–2500 ₽ (depending on the model).
• 💰 Xiaomi Mi/Mi Mix: 2500–4000 ₽.
• 💰 Flagships (Xiaomi 13, Black Shark): 4000–6000 ₽.

⚠️ Warning: If you choose to replace the battery yourself, use only original Xiaomi-labeled batteries or certified counterparts (e.g., from ZMI). Cheap AliExpress batteries often have understated capacity and can swell even faster.

6 How to extend the life of Xiaomi battery: 10 rules from engineers

Compliance with these recommendations will help to avoid bloating and increase battery life by 30-50%:

• 🔋 Keep charge between 20% and 80%: Full cycle (0–100%) wears out the battery faster. Enable the option "Optimized Charging" (Settings → Battery → Battery Status) in the settings.
• ⚡ Use the original RAM: Even if the phone supports Quick Charge 3.0, it is better to charge it with a standard adapter on 18W than a cheap one on 30W.
• 🌡️ Avoid extreme temperatures: Do not leave your phone in the sun or near a heater.The optimum operating temperature is 10–35°C.
• 📵 Do not play heavy games while charging: This increases battery heating by 15–20°C.
• 🔄 Calibrate once every 3 months: Discharge the phone to 0%, then charge to 100% without interruption.
• 🛠️ Update firmware: Newer versions of MIUI often fix power management bugs.
• 🚫 Don't use wireless charging all the time: It heats the battery more than wired charging.
• 📦 Store your phone with a charge of 40-60%: If you don't use it for a long time.
• 🔍 Check battery status: Enter the code ##4636## and check the Battery health setting in the engineering menu.
• 🛒 Buy phones with batteries from trusted suppliers: In Xiaomi, it’s ATL, BYD or Sunwoda.

According to Battery University tests, a battery that always charges up to 80% and discharges up to 30% will last 3-4 times longer than a battery with cycles of 0-100%.

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The most common mistake Xiaomi users make is to leave the phone on charge overnight, which leads to overcharging and accelerated battery degradation, even if the original RAM is used.

7. Myths about Xiaomi's battery bloating: What doesn't really affect

There are a lot of battery care tips online that don't really have a scientific basis, and we're going to look at some of the most popular myths.

• ❌ "Fast charging spoils battery": Modern power controllers (e.g. Xiaomi 12T) automatically reduce current as you charge. Fast charging up to 80% is no more harmful than normal.
• ❌ "You have to completely discharge your phone once a month": This was true for nickel metal hydride batteries 20 years ago. Lithium-ion batteries, on the contrary, deteriorate from deep discharges.
• ❌ "Closure of background applications saves charge": MIUI itself optimizes background processes. Manual closure of applications, by contrast, can increase battery consumption due to reruns.
• ❌ Cold weather kills battery: Low temperatures temporarily reduce capacity but do not cause permanent damage (unlike overheating).
• ❌ “Cover interferes with cooling”: Modern cases (such as the original ones for Xiaomi 13) have vents and do not affect temperature.

The only myth that has a fair bit of truth is that charging from the USB- port is safer. Indeed, USB 2.0 gives a maximum of 0.5A, which reduces heat, but it takes 3-4 times longer to charge, and for high-capacity batteries (for example, 5,000 mAh in POCO M5), this can lead to undercharging and cell imbalance.

FAQ: Frequent questions about Xiaomi's battery bloating