LEGO Mindstorms EV3 Rechargeable DC Battery Description
Designed for use with the LEGO EV3 Intelligent Brick, this Lithium Ion rechargeable DC battery gives you an alternative to normal AA batteries. Capacity: 2050 mAH. Estimated recharge time 3 – 4 hours. Requires the (45517) LEGO Transformer 10V DC charger which is sold separately.