Sphero RVR+ Spare Battery (RVR Compatible)New and improved rechargeable and swappable battery to keep RVR and RVR+ programs, inventions, and classroom projects running without any downtime. Replace your battery or power up your RVR+ while your other battery charges. Pick up an additional battery so that driving, coding, and hacking never stop. Fun never ends charge one battery while the other is working High capacity delivers enough juice to power RVR+ and anything you add to it Compatible