Maybe 2nd best $20 new accessory?? Turns any 18v ryobi battery into a usb power bank. This guys isn't getting any love but I think it's pretty neat too. : r/ryobi
18V ONE+ 150 WATT CHARGING POWER SOURCE - RYOBI Tools
LastDan Compatible AC DC Adapter Compatible With Ryobi HP722 HP722K 7222701-2PK 722110 3/8" 7.2V Cordless Drill Driver 7.2V D.C. 7.2V DC 7.2VDC Volt 7.2 Volts (NOT fit Ryobi SA721 7.2V Drill.) - Walmart.com
Ryobi One+ 18V USB Power Adapter - YouTube
toolboy's Corner: Ryobi 18v to 40v Adapter and Extended Runtime Battery Bank
Amazon.com : Alian for Ryobi 150 Watt Powered Inverter Generator,18V DC to AC 110V 120v,as Portable Power Source,for Ryobi 18 Volt lithium Battery USB Charger Adapter,for Ryobi Power Station with LED Light :
18V ONE+ 150 WATT CHARGING POWER SOURCE - RYOBI Tools