How to charge Xiaomi Redmi 9 after buying: myths and real tips 2026

The new Xiaomi Redmi 9 is always a thrill and a desire to keep it running for as long as possible. But from the first minutes of use, the question arises: how to properly charge your phone after buying so that the battery lasts as long as possible? The Internet is full of conflicting tips - from "discharge to 0%" to "keep on charging for 12 hours," most of them outdated or simply harmful to modern lithium polymer batteries.

This article is not just a summary of the general guidelines, but we're going to look at the specific settings of Redmi. 9, Explain why the first cycle of charging does not require “special training” and show how to avoid typical errors that reduce battery capacity by a few hours. 20-30% All tips are based on official Xiaomi recommendations and battery technology research. 2023-2026 year-end.

Myths about the first charge: what really needs to be done with the Redmi 9

The most common myth is that the first time a phone needs to be charged. 8-12 This rule was relevant for nickel-metal hydride batteries. 2000-The x-years, but Redmi. 9 equipped with a lithium polymer battery 5020 The current battery packs have no memory effect, and long-term charging after reaching the target. 100% It causes overheating and degradation of elements.

What is really important to do when you first switch on:

• 🔋 Wait for the full discharge before turning off (if the phone came with a charge). 30-50%, Use it before you turn it off automatically. This is not for calibration, but to check the actual capacity of the battery.
• ⚡ Charge up to 100% with the original charger (complete with Redmi 9 comes power supply) 10W or 18W, depending on the region).
• 📱 Do not interrupt the process - let the phone charge to the end without interruptions in power.
• ⚙️ Activate the "Optimized Charging" mode in the settings (more on it in the next section).

A critical nuance for Redmi 9: If the phone came with a charge lower 20%, Don't turn it on right away. Connect to the charger on the 15-20 You can do the initial setup for a minute, and then you can do the initial setup, because when you're in a deep discharge, the battery controller can block charging to the minimum voltage threshold.

2.Redmi 9 settings that extend battery life

V MIUI (Xiaomi firmware has hidden and explicit features that directly affect battery wear, and most users don't include them, although they can extend battery life on the battery. 30-40%.

1. Optimized charging (Adaptive Charging)

This function limits charging at the level 80-90%, If the phone is connected to the network for a long time (for example, at night). 9 The worst thing is the constant maintenance. 100% The scaling up of the charge accelerates the degradation of 2-3 once.

How to turn on:

1. Go to Settings → Battery and Performance.
2. Select Battery Settings → Optimized Charging.
3. Activate the switch and set a schedule (for example, from 23:00 to 7:00).

2. Limitation of application activity background

Background processes (especially messengers and social networks) can discharge the phone to the Internet. 15-20% overnight. MIUI There is a tool to control them:

• 🛑 Open the Settings. → Annexes → Permits → Autostart and disable Autostart for unnecessary programs.
• 🔄 B Settings → Battery → Select Battery Mode Select Energy Saving or Balanced (but not Performance!).

Insert "Optimized charging"|Limit Auto-Run Applications|Select the “Balanced” regime"|Turn off vibration when typing|Set a dark topic (AMOLED-There is no screen, but it reduces the load on the GPU)-->

Temperature control

Redmi 9 automatically disables fast charging at battery temperature above 40°C, but it's best not to bring it to that:

• 🌡️ Do not charge your phone in the direct sun or near heat sources (such as on the dashboard of a car).
• 🎮 Avoid gaming while charging – this raises the temperature of the Helio processor G80 and, as a result, batteries.
• 🧊 If the phone overheats, disconnect it from charging and let it cool until 30-35°C (checked in Settings) → The phone. → Battery status).

💡

If you use the case while charging, remove it - this will improve the heat sink and reduce the temperature of the battery on the battery. 3-5°C.

3. Which charger to use for Redmi 9

Included with the Redmi 9 is a charger with power 10W or 18W (Many users think, "The more powerful the better," but that's not always the case. Here's what you need to know:

Why you should not use charging 33W+?

Redmi 9 doesn’t support ultrafast charging – its battery controller is designed to be as fast as possible 18W. When connecting a more powerful unit:

• 🔥 The phone will warm up more, which reduces the battery life.
• ⚡ Charging will still not accelerate – the limitation of the controller will work.
• 💥 The risk of port damage USB-C when using poor-quality cables.

Can I use chargers from other phones?

Yes, but with reservations:

• ✅ Allowed: Charging from Redmi Note 8/9, Poco X3 (18W).
• ⚠️ With caution: charging from Samsung (15W) iPhone (5W–20W) — They can charge more slowly.
• ❌ Cheap no-name charges without certification – they can damage the battery.

How often to charge Redmi 9: optimal schedule

Redmi 9 lithium polymer batteries have a limited number of charging cycles (about 500-800 to 20% capacity reduction).

1. Optimal charge range: 20-80%

According to Battery University research, the battery will last the longest if it is kept in charge at this interval, and full cycles of 0-100% accelerate degradation.

• 🔋 Connect the charger when there are 15-20 left%.
• ⚡ Turn off when you reach 80-90% (unless you need full capacity).

2. How many times a day can I charge?

No hard limits, but:

• ✅ Ideal: 1-2 times a day in short sessions (for example, from 20% to 70%).
• ⚠️ Allowable: 3-4 times if you use "Optimized Charging".
• ❌ Harmful: Constant “recharge” (connection for 5-10 minutes every half hour) – this creates microcycles that are summed up in full.

3. Do I need to discharge the phone to 0%?

No! Deep discharge (0%) is one of the most harmful factors for lithium polymer batteries. Redmi 9 has full discharge protection (switches off at 3-5%), but even this reduces battery life.

⚠️ Warning: If your phone is dead before it goes off, don't leave it in this state for long. Connect to charging for a day or the battery may fail.

💡

The most harmful scenario for the Redmi 9 battery is to keep 100% charge (e.g., at night) + High temperature (play or sunlight) This mode reduces battery life by 2-3 times.

5.Typical bugs that kill Redmi 9 battery

Even experienced users sometimes make these mistakes without realizing the consequences:

1.Use of the phone while charging

Playing games, video, or navigating while charging increases battery temperature by 10 to 15 times°C, which is equivalent to doubling the degradation over the same period. If you need to call urgently, use a wired headset to reduce the heat.

2. Charging "in a hurry" with cheap power bank

Many external batteries (especially without certification) give off unstable voltages, which leads to:

• 🔥 Overheating of the charging controller.
• 📉 Incorrect display of the charge level (the phone can show 100% when the real 85%).
• ⚡ Short-circuit risk (in cheap models without protection).

3. Keeping the phone discharged

If you don't use the Redmi 9 for a few weeks (like a spare phone), a dead battery can lose capacity irrevocably, with 40 to 60 percent optimal storage.

⚠️ Warning: If the phone has been dead for more than 3 months, its battery could go into "deep discharge", in which case conventional charging will not help - you will need to "resuscitate" using a special device (for example, iMax). B6).

4. Ignoring firmware updates

Xiaomi regularly releases updates that optimize energy consumption. MIUI 14 added an improved battery management algorithm for Redmi 9 that reduces wear by 10-15%. → The phone. → Updating the system.

6 How to check the status of the Redmi 9 battery

To see if your battery is damaged, use these methods:

1. Built-in diagnostics MIUI

Go to Settings. → The phone. → Battery status. Here's the display:

• 📊 Wear level (if supported by your version) MIUI).

Third-party annexes

For a detailed diagnosis, install one of these apps (available on Google Play):

• 📱 AccuBattery – shows real capacity, discharging speed and temperature.
• 🔋 Battery Guru – monitors charging cycles and predicts lifespan.
• 📊 Ampere – Measures the charging/discharge current in real time.

3. Self-discharge test

If the phone is running too fast in standby mode, check:

1. Charge to 100% and disconnect from the network.
2. Turn off Wi-Fi, mobile data and geolocation.
3. Leave your phone for 8-12 hours without use.
4. Check the charge level: ✅ Normal: loss 1-3%. ⚠️ Suspicious: 5-10% (possibly the fault of the software). ❌ Critical: 15%+ (faulty battery or controller).

If self-discharge is high, try resetting to factory settings (Settings) → Additionally. → Recovery and resetting. If that doesn't work, the battery needs to be replaced.

7.When and how to replace the battery with a Redmi 9

The average life of the Redmi 9 battery is 2-3 years if properly operated, and replacement is required if:

• 🔋 The phone discharges in 3-4 hours without loading.
• ⚡ Charging is too fast (e.g., up to 100% in 30 minutes) – a sign of capacity loss.
• 🌡️ The phone is overheating even with a simple charge.
• 📉 In AccuBattery, the real capacity is less than 3000 mAh (originally 5020 mAh).

Where do you replace the battery?

How to choose a battery to replace?

The original battery for the Redmi 9 is marked BM47 or BM48 (Depending on the version, check when buying:

• 🏷️ The presence of a hologram Xiaomi on the packaging.
• 🔋 Capacity of at least 5000 mAh (on the battery label).
• 📅 Date of production (not older than 6 months).

⚠️ Warning: After the battery is replaced, be sure to calibrate: Charge to 100% and keep on charging for 1 hour. Discharge to 0% (until the phone turns off). Repeat the cycle 2-3 times. This is necessary for the controller to work correctly.

8. FAQ: Frequent questions about charging Xiaomi Redmi 9