Battery Powered Fan

Mustafa is the place for everything.  The target market is Indians and Bangladeshi.  So it is my first time to see battery powered fan.  I feel stupid to buy the old type of fan use by yellow top taxi of yore days.  Now the battery powered fan is like a regular fan.  Some come with light and radio.  I am looking for a normal fan to be charge by my solar panel.  Unfortunately, all the fans are using 6V rechargeable batteries.  So I will have to find a controller to step down my 12V output to 6V.  Right now I have another option.  So I should explore Mustafa more to find more battery powered device.