Windows Registry Backup.

I want to set backup of registry for specific keys and folders. For that i use below command. 

"reg export HKLM\Software\etc E:\RegBakFolder\etc.reg /y" the issue is if i use"/y" then its will  Overwrite the existing file. i want command which will create new file every day with date and time + name which i give. is it possible.

Akshay Pate