Simply put, a 20V battery lacks the capability to power a 60V tool, and Flexvolt tools can't adjust to lower voltages. That ability stems solely from Flexvolt batteries. Thus, you'll need 60V or ...

The brand's 18V system uses high-performance lithium batteries that can power tools both small and large, and which are interchangeable, so you can use any Ryobi 18V battery with one of its 18V tools.