You own a Xiaomi Redmi Note 9 Pro and wonder how long its battery will last? This smartphone, launched in 2020, has a 5020 mAh battery, one of the largest in its class. But even those powerful batteries degrade over time. In this article, we'll look at how many charging cycles the Redmi Note 9 Pro can withstand, according to the manufacturer, and independent tests, how to check the current wear of the battery, and what to do to maximize its life.
Now, to be clear, the concept of a charging cycle is often misunderstood. Many people think it's one full charge from 0% to 100%. In fact, one cycle is the energy consumption equal to the full battery capacity. For example, if you today discharged your phone from 100% to 50%, and tomorrow again to 50%, it would be one full cycle, although you did charge twice, and this is important for understanding the real life of the battery.
Xiaomi: How many cycles the manufacturer guarantees
Xiaomi in the technical documentation for the Redmi Note 9 Pro indicates that the lithium-polymer battery of the smartphone is designed for 500-600 full charging cycles while maintaining at least 80% of the original capacity.
- 🔋 Real tests show that with careful use, the battery can last 700-800 cycles, but with a gradual decrease in capacity after the 500th.
- 📉 After 300-400 cycles, many users report a 10-15 reduction in battery life%.
- ⚡ Fast charging (30W In this model) accelerates battery degradation by 15-20% compared to slow charging 5W.
It is important to understand that Xiaomi tests batteries in the laboratory at temperatures of 20-25 ° C and moderate loads.
- 🌡️ Overheating (such as charging in the sun or during games).
- ❄️ Storage of a discharged smartphone (below 20% for more than a month).
- 🔌 Use of non-original chargers with unstable voltage.
How to check the number of charging cycles on the Redmi Note 9 Pro
Unfortunately, Xiaomi does not provide direct access to the charging cycle meter in standard settings, but there are several ways to assess battery wear:
- Enter the code ##4636## in the Phone app, then select Battery Information. Here you will see the level and health setting. Health is 100%, but after 500 cycles it can drop to 75-85%.
- Diagnostic applications: Utilities like AccuBattery (Android) or AIDA64 show the approximate number of cycles by estimating battery capacity, for example, if the original capacity was 5020 mAh, and now 4200 mAh is a signal of severe wear.
What to do if your battery is below 70%?
For more accurate diagnosis, you can use ADB-Connect the phone to the PC, turn on the debugging. USB In the developer settings and execute:
adb shell dumpsys batteryFind the line in the conclusion charge_counter — This is the number of milliamp hours that have been through the battery over time. 5020 (rated capacity - get the approximate number of cycles.
Factors that accelerate battery wear Redmi Note 9 Pro
Even if you follow charging cycles, some habits can shorten battery life by 2-3 times.
| Risk factor | Impact on the battery | How to avoid |
|---|---|---|
| 🔥 Overheating above 40°C | It accelerates degradation by 3-5 times. At 45°C, the battery loses 30% of its capacity in 3 months. | Don't play heavy games while charging. Use heat sink covers. |
| ⚡ Fast charging. 30W | Reduces cycles by 15-20% compared to 5W-charging. | Use slow exercise at night, fast – only if necessary. |
| 🔋 Storage discharged | At 0% charge, the battery degrades by 2-5% per month. | If you don’t use your phone for a long time, leave 40-60% charge. |
| 📵 Deep discharge (below 10%) | Each discharge up to 0% "eats" 1-2 cycles. | Charge your phone at 15-20% charge. |
💡
If your Redmi Note 9 Pro is running out quickly, check not only the battery, but also the power consumption of the applications. Go to Settings → Battery → Battery Use and sort the list by consumption. Often the fault of messengers or games running in the background.
⚠️ Note: If after the update MIUI The battery has fallen dramatically, and it's not always the battery's fault. New firmware versions may contain bugs that increase power consumption. Try to roll back on the previous version or wait for a patch.
How to prolong the life of the battery: proven methods
A few simple rules will help keep the Redmi Note 9 Pro battery capacity at 85-90% even after 500 cycles.
Use the original charger 30W|Avoid overheating above 35°C|Charge to 80-90%, not 100%|Avoid a rank below 15%|Store at 40-60% charge if you do not use it for a long time-->
1. Optimize the charging process:
- 🔌 Charge your phone with short sessions (e.g. 20–80%) instead of a full cycle of 0–100.
- ⏱️ Avoid overnight charging. Use smart timer outlets or manually turn off power after reaching 80-90%.
- ☀️ Do not leave your phone on charge in direct sunlight or near heat sources.
2. Set up software optimization:
- 📱 Enable Adaptive Battery in Settings: Settings → Battery → Battery mode → Adaptive battery: This will limit background activity of rarely used applications.
- 🔄 Turn off Auto-Update apps in the background (in Google Play).
- 🌙 Use a dark theme of design — AMOLED-Redmi Note 9 Pro uses 15-20% less power when displaying dark colors.
3.Control the physical condition:
- 🛠️ Avoid mechanical damage (shocks, falls) that can disrupt the integrity of the battery.
- 💧 Do not allow moisture to enter the charging connector - this can cause corrosion of contacts and unstable nutrition.
💡
The most effective way to extend the life of the battery is to avoid extreme conditions: to prevent overheating, deep discharge and constant charging to 100%.
When to change the battery: signs of critical wear
Even with careful use, after 2-3 years, the Redmi Note 9 Pro battery will begin to lose capacity.
- 🔋 The phone discharges by more than 50% in 2-3 hours in standby mode (without active use).
- ⚡ When connecting charging, the charge increases in leaps (for example, from 10% immediately to 40%, then back to 15%).
- 🔥 The phone is very hot even with minimal load.
- 🛑 Smartphone shuts down at 20-30% charge, although the indicator shows the rest of the battery.
- 📉 In diagnostic applications, battery capacity is less than 60% of nominal (less than 3000 mAh).
If you see at least 2-3 of these signs, the battery needs to be replaced. Xiaomi recommends contacting authorized service centers that use original batteries. The cost of replacing in 2026 is 1500-2500 rubles (depending on the region).
⚠️ Warning: Buying cheap battery analogs can cause battery bloating and damage to the motherboard.The original battery for the Redmi Note 9 Pro is labeled BM4B or BM4C and comes in sealed package with hologram.
Comparison with competitors: how the Redmi Note 9 Pro holds the charge
For objectivity, compare the Redmi Note 9 Pro with other popular smartphones of 2020-2021 in terms of the number of charging cycles and storage capacity:
| Model | Capacity (mach) | Cycles up to 80% capacity | Average wear and tear for the year |
|---|---|---|---|
| Xiaomi Redmi Note 9 Pro | 5020 | 500–600 | 10–15% |
| Samsung Galaxy A51 | 4000 | 400–500 | 15–20% |
| Realme 6 Pro | 4300 | 450–550 | 12–18% |
| POCO X3 NFC | 5160 | 500–600 | 8–12% |
As you can see from the table, the Redmi Note 9 Pro performs better than many competitors thanks to:
- ⚡ Slower degradation (5-10% less wear per year).
- 🔋 Higher initial capacity, which compensates for the loss.
- 🛠️ Quality food management system in MIUI.
However, the Snapdragon 720G models (like the Redmi Note 9 Pro) have a feature: the processor warms more than competitors on the Helio G90T or Exynos 9611. This can accelerate battery wear under intense loads (games, video editing).
Myths about charging smartphones: what is true and what is not
There are many myths surrounding battery charging, and we will discuss the most common ones in relation to the Redmi Note 9 Pro:
- 🔌 Myth 1: "You have to completely discharge your phone once a month to calibrate your battery." Reality: For today's lithium polymer batteries, it's bad. A full discharge of up to 0% reduces battery life. Calibration is required only if the charge indicator shows incorrect values (for example, jumps from 50% to 20%).
- ⚡ Myth 2: "Fast charging ruins the battery in a few months." Reality: Fast charging does increase wear, but not critically. With proper use (no more than 2-3 times a week), the difference will be 50–100 cycles in 2 years.
- 📵 Myth 3: "You can only charge your phone with the original cable." Reality: It's not the cable that matters, it's the voltage stability. USB-IF) harmless.
- 🔋 Myth 4: "If you leave your phone on charge after 100%, the battery will explode." Reality: Modern smartphones turn off power after full charge. The risk of bloating or fire only occurs when you use faulty chargers or mechanically damage the battery.
Another popular question is, "Can I use my phone while charging?" The answer is yes, but with reservations:
- 🎮 Avoid resource-intensive tasks (games, video calls) that load the processor and cause overheating.
- 📞 Short actions (watching chats, calling) will not cause harm.