OR keep the bin file on the sd card (as DJI recommends)
If you leave the .bin file at the root then every time you power up your drone even if it up to date it will run through an update sequence, not finding anything to update, and will not initialize for flight. This has been my experience. As my new batteries were purchased I moved to proper .bin back to the root of my card and ran through the upgrade sequence and the log files show after a 5-10 minute wait that the battery was upgraded. If the .bin is left on the card then on power up 5 minutes of beeping occurs and it goes to green. Log shows not elements were upgraded.