I just figured out something. At least for every phone I came across today and even my Android Emulator had the SD Card Path like ' /storage/????-???? ' where every ? is a capital letter or a digit.
So, if /storage/ directory has a directory which is readable and that is not the internal storage directory, it must be the SD Card.
My code worked on all phones I tested and even on my android emulator!
String removableStoragePath;
File fileList[] = new File("/storage/").listFiles();
for (File file : fileList)
{ if(!file.getAbsolutePath().equalsIgnoreCase(Environment.getExternalStorageDirectory().getAbsolutePath()) && file.isDirectory() && file.canRead())
removableStoragePath = file.getAbsolutePath(); }
//If there is an SD Card, removableStoragePath will have it's path. If there isn't it will be an empty string.
If there is an SD Card, removableStoragePath will have it's path. If there isn't it will be an empty string.