A month after sorting a similar issue for PlayStation 4, it looks like Sony has also deployed a fix for PS5's dead battery issue.
As with PS4, the issue here was a loss of access to digital games when the console's internal CMOS battery failed.
The CMOS battery powers an internal clock which the console uses to check eligibility for game ownership. If the battery failed, or simply ran down naturally, access to most games would be blocked until an online check could be made.
Some physical games were also affected. Still, as you might expect, this was a particular concern for owners of the PlayStation 5 Digital Edition.
The one exception to this is games you don't own but may have unlocked access to via a PlayStation Plus subscription. These will still not boot.
The PlayStation CMOS battery issue first came to light back in April, when it was flagged by Does it play?, a Twitter account devoted to game accessibility and preservation.
Of course, most PS4 and PS5 consoles have not (yet) experienced a CMOS battery death. Even if (when) yours does drain, it's fair to say most consoles are connected to the internet so an online check can still be performed. Still, fans said the way this worked needed to change to avoid future problems for PlayStation owners who play offline, or to preserve the ability to play games long-term even if PlayStation Network is taken down.