Xiaomi Redmi 9 remains one of the most popular budget devices of the brand, but the question of proper charging is often confusing. Users face problems: the battery discharges too quickly, then charging is “at the speed of a turtle”, or even the phone refuses to charge from the “non-native” power supply.
In this article, we will discuss which charging is really suitable for the Redmi 9, which parameters are important (voltage, current, fast charging protocols), and give practical tips for choosing accessories. We will focus on original and certified analogues to avoid risks to the battery. If you want to extend the battery life or just speed up the charging process, read on.
Technical Charging Specifications of Xiaomi Redmi 9
Smartphone Xiaomi Redmi 9 is equipped with a factory charger with the following parameters:
- 🔌 Type of connector: USB Type-C (note: this is not microUSB!)
- ⚡ Power: 10W (5V/2A)
- 🔄 Charging protocol: standard USB BC1.2 (without Quick Charge or Power Delivery)
- 📦 Component: power supply + cable USB-C — USB-A (1m long)
It’s important to understand that the Redmi 9 doesn’t support fast charging in the classic sense (like the flagships of Xiaomi or Samsung).The maximum power that a phone can digest is 10W. This means that even if you plug in an 18W or 30W power supply, the charging speed won’t increase. Moreover, using too powerful charging can shorten battery life due to overheating.
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If your Redmi 9 is charging slower than before, check the cable - often the problem lies in the damaged wires inside the plough, not in the power supply.
Original charging vs. analogues: what to choose
The manufacturer recommends using the original charger from the kit, but in practice this is not always possible.
| Type of charging | Advantages | Deficiencies | Price (exemplary) |
|---|---|---|---|
| Original (Xiaomi) | ✅ Optimized for the model✅ Safety for the battery | ❌ More expensive than analogues❌ Hard to find at retail | 800 ₽ |
| Certified analogues (Baseus, Anker) | ✅ Cheaper than the original.✅ Wide choice | ❌ Risk of running into a fake❌ It may not support all protocols. | 300 ₽ |
| No-name (Chinese brands) | ✅ Very cheap. | ❌ Risk of overheating/fire❌ Could ruin the battery. | 100 ₽ |
If you decide to buy an analogue, pay attention to:
- 🔍 Certification: Look for the labeling CE, RoHS or UL case.
- 📏 Cable length: optimally - 1-1.5 m (long cables lose power).
- 🔋 Power: no higher 10W (5V/2A), Otherwise, the phone will limit the current.
Can I charge Redmi 9 with a charge from other devices?
Many users are trying to save money by using chargers from old phones or other gadgets.
- 📱 Charging from Redmi Note 8/9: It's fine if the power is good. ≤10W (But Notes often have blocks on 18W — They are not dangerous, but they will not speed up charging).
- ⚡ Charging from the iPhone: 5W (1A) — The Redmi 9 will be charged 2 times slower!
- 🔌 Charging from the tablet (for example, 12W): The phone will only take 10W, But the risk of cable overheating is higher.
- 💻 Laptop charger (USB-port: usually 0.5–1A — It is enough to recharge when used actively.
The critical point is that if you use a charge above 10W, the phone will automatically limit the current to safe values, but the cable can overheat — especially if it is thin or damaged. For example, connecting to a 30W unit through a cheap cable sometimes leads to melting of the insulation.
What happens if you use a powerful charger constantly?
How to speed up the charging of Redmi 9: working ways
While Redmi 9 doesn’t support fast charging, there are a few legal ways to reduce charging times by 15-20%.
Turn on the aircraft mode (disables background processes)|Use the original cable (without damage)|Charge at 10-30 temperatures°C|Do not use your phone while charging.|Turn off fast charging in settings (if enabled)-->
It is also worth paying attention to:
- 🌡️ Temperature: If the phone overheats (e.g., lying in the sun or under a blanket), charging automatically slows down.
- 🔋 Battery status: If the capacity has dropped below 80%, the charging speed may decrease (check in Settings). → Battery → Battery status).
- 📴 Background applications: Closing heavy games (e.g. Genshin Impact or PUBG) speed up.
Note that MIUI has a hidden setting that limits charging to 80% to extend battery life.
- Go to Settings. → Battery.
- Put it on the icon. ⚙️ top-right.
- Select Optimized Charging and deactivate the function.
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The most efficient way to speed up charging is to use the aircraft mode and the original cable, which reduces time by 20 to 25 percent without risking battery life.
Frequent charging problems and their solutions
If your Redmi 9 isn’t charging or charging too slowly, check the following:
| Problem. | Possible cause | Decision |
|---|---|---|
| The phone is not charging at all. | 🔌 Core or connector damaged🔋 Power supply malfunctioned. | Try another cable/charging. Check the connector for debris. |
| Charging is going very slowly. | 📱 Heavy applications included🌡️ Phone overheats | Close the games, put the phone in airplane mode, let it cool down. |
| Charging is interrupted | 🔌 Bad contact in the connector🔋 Worn-out battery | Clean the connector with a toothpick (carefully!) Check the battery status in the settings. |
| The phone is charged only when it is off. | 🔋 Failure of the power controller📴 Software failure | Reset the settings to the factory or contact the service. |
If none of these methods worked, the problem may be battery wear or damage to the food board, in which case it is better to contact the service center. The average cost of replacing the battery for the Redmi 9 is 1,500-2,500 ₽ (depending on the region).
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Before visiting the service, check if the warranty works. Even if the phone is purchased a long time ago, some stores give an extended battery warranty (check with the seller).
Safety: How not to damage the battery
Incorrect charging is one of the main reasons for premature battery wear. To prolong the life of the Redmi 9 battery, follow these rules:
- 🔥 Avoid overheating: Do not charge your phone in direct sunlight or near heat sources (e.g., on a heating battery).
- 🔌 Do not use damaged cables: if the wiring is broken or the wires are bare, replace the cable - this can lead to a short circuit.
- 📵 Do not discharge to 0%: optimal charging range is 20-80%. Full discharge and charge up to 100% reduce the life of the battery.
- ⚡ Don’t leave it on overnight charging: after reaching 100%, the phone continues to be recharged with “microcurrents”, which is harmful to lithium-ion batteries.
⚠️ Warning: If you notice that the phone gets too hot during charging (hotter than usual), immediately disconnect it from the mains.This may be a sign of a malfunction of the battery or power supply!
Also worth paying attention to is the quality of the outlet, if it's old or loose, it can lead to power surges that are harmful to electronics, ideally using a network filter or voltage stabilizer.
Alternative charging methods: power bank, wireless charging, car
Xiaomi Redmi 9 supports not only classic charging from the socket, but also other methods.
- 🔋 Power Bank (External Battery):
- 🚗 Charging in the car:
- 📶 Wireless charging:
⚠️ Warning: If you use wireless charging with an adapter, monitor the temperature of the phone. Due to the additional heat from the coil, the risk of battery overheating increases by 1.5-2 times.
For car charging, we recommend using adapters with surge protection, for example:
- Xiaomi Car Charger Pro (2 ports, 18W)
- Baseus Car Charger (with Quick Charge 3.0 support, but the phone will only take 10W)