Combining flash drive with Xiaomi phone memory: full instruction

Xiaomi smartphone owners often face a shortage of internal memory, especially if a device from the budget line of Redmi or POCO with 32/64 GB on board. One effective solution is to combine an external microSD card with internal storage through the Adoptable Storage function. This mechanism, implemented in Android since version 6.0, allows you to expand the amount of available memory at the expense of a flash drive, but has its nuances on the MIUI firmware.

It is important to understand that once combined, the flash drive becomes an integral part of the system: it cannot be removed without losing data or resetting settings. In addition, not all Xiaomi models officially support this feature – in some cases, manual activation through ADB will be required. In this article, we will discuss all the current ways to combine memory, storage requirements, and possible risks and limitations.

What is Adoptable Storage and How Does it Work for Xiaomi?

Adoptable Storage is a technology proposed by Google in Android 6.0 Marshmallow that allows you to format an external drive (microSD or USB-OTG) as part of the device's internal memory.

• 📁 The flash drive is encrypted and tied to a specific phone – it can not be used on other devices without formatting.
• 🔄 Applications and their data can be automatically installed on an external drive (if the appropriate behavior in the settings is selected).
• ⚠️ System speed may decrease if a slow microSD is used (class below). A1 or UHS-I).

On Xiaomi smartphones, this feature is often hidden or disabled by default.

1. MIUI firmware is optimized to work with internal eMMC/UFS memory, which is much faster than even top-end microSDs.
2. Risk of data loss when a flash drive is extracted or a system crash.
3. Not all applications work correctly with external memory (especially games and services with protection against piracy).

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Before combining, check your microSD speed with the A1 SD Bench app – if your read/write scores are below 10MB/s, drop the idea: the system will slow down.

Requirements for a flash drive to combine with Xiaomi memory

Not every microSD is suitable for expanding internal memory.

Critical note: flash drives with fake labeling (for example, "128 GB" at a price of 300 rubles) not only will not be suitable for combining, but can also disable the microSD slot in the phone. H2testw beforehand.

Also consider:

• 🔋 The combined drive will consume additional energy, which can reduce battery life by 5-15%.
• 🔄 Once combined, it will not be used as a portable drive (for example, to transfer files to a PC).
• 📱 On some Xiaomi models (e.g. Redmi Note 10 Pro) the function is stable, and on others (e.g., Redmi Note 10 Pro, POCO X3 NFC) may require manual activation through ADB.

Method 1: Connecting through standard MIUI settings

On some Xiaomi models (mainly with MIUI 12 firmware and later), the memory merge function is available out of the box.

Insert the microSD into the phone slot (not through the phone) OTG-adapter)|

Backup the data from the flash drive (it will be formatted)|

Charge your phone at least 50% |

Connect to a stable Wi-Fi network (recommended)-->

Instructions:

1. Open the Settings → Memory.
2. Tap by the name of your microSD (for example, "SD-128GB card").
3. In the upper right corner, press three dots (⋮) and select Storage Settings.
4. Choose Format as an internal memory.
5. Confirm the action and wait until the process is completed (it can take up to 10 minutes).

If you don't format as internal memory, your model doesn't support the function through the GUI. Go to the ADB method.

Method 2: Manually combine via ADB (for all models)

If the standard method is not available, use the command line ADB (Android Debug Bridge), which works on most Xiaomi devices, but requires activation of the developer mode.

Step 1: Preparation:

• 📱 Enable Developer Mode: Go to Settings → About the phone and 7 times tap on the item Version MIUI.
• 🔧 Back to Settings → Additionally. → For developers and activate debugging by USB.
• 💻 Install. ADB on PC (for example, through Google’s Platform Tools or Minimal) ADB and Fastboot).

Step 2: Connect and commands:

1. Connect your phone to your PC through USB-cable (original!).
2. In the command line (or PowerShell), do: Adb devices make sure your device appears in the list.
3. Enter the command to verify the USB flash drive ID: adb shell sm list-disks Remember the value after the disk: (e.g. 179,128).
4. Run the unification command (replace X,Y with your values): adb shell sm partition disk:X,Y private

Step 3: Completion:

• 📲 The phone will be notified about formatting – confirm it.
• ⏳ Wait until it is completed (may take up to 15 minutes).
• 🔄 Reset the device.

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Once combined via ADB, the flash drive will be formatted to a f2fs or ext4 file system, which improves performance but makes it unreadable on other devices.

How to transfer applications to a combined flash drive

Even after successful integration, not all applications will automatically move to an external drive to optimize memory usage:

Method 1: Through application settings:

1. Go to Settings → Applications → Application Management.
2. Select the desired application and tap the Warehouse.
3. Click Change and select SD-Card (if the option is active).

Method 2: Through ADB (for forced transfer):

adb shell pm move-package com.example.app android_external_storage

Replace com.example.app with the batch name of the app (you can find out through the App Inspector).

Limitations:

• ❌ Google System Applications and Services Cannot Be Delayed.
• ❌ Some games (such as Genshin Impact or PUBG Mobile Refuse to Work with External Memory.
• ⚠️ After updating MIUI Apps can “fly” from the flash drive.

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Use AppMgr III (App 2 SD) to transfer supported applications to external memory.

Frequent problems and their solutions

When combining a flash drive with Xiaomi memory, users face typical errors.

⚠️ Warning: If the phone starts to slow down after the combination, check the speed of microSD. Using a Class 4 or lower card leads to delays of up to 2-3 seconds when opening applications.

If files from the flash drive are missing after the merger:

• 🔍 They are not deleted, but transferred to the folder. /Android/obb/ or /Android/data/ externally.
• 📂 Use a file manager with root rights (for example, FX File Explorer for access to hidden directories.

How to cancel the union and return the flash drive to its original state

If you decide to abandon the extended memory, you can return the microSD to normal mode in two ways:

Method 1: Through MIUI settings:

1. Go to Settings. → Memory.
2. Slip on the combined flash drive and choose Format as portable.
3. Confirm the action – all data will be deleted!

Method 2: ADB (if the first method is not available):

adb shell sm forget X,Y

Where X,Y is the disk identifier (you can find out the sm list-disks command).

⚠️ Warning: After the cancellation of the combination, all data from the flash drive will be erased and the applications installed on it will cease to work. MIUI Backup or Titanium Backup (root required).

If the flash drive is not formatted:

• 🛠️ Connect it to your PC and use the utility SD Formatter with Full (Erase) option).
• 🔧 If the card is not identified, check it on another device – it may have failed.

FAQ: Answers to popular questions