Rechargeable DC Battery by LEGO® Education (45501)

The lithium-ion EV3 Rechargeable DC Battery is designed for use with the EV3 Intelligent Brick and features a capacity of 2050 mAh. It provides a longer run time than AA batteries and can be charged without taking the model apart. The battery is included in the EV3 Education Core Set and has a charge time of around three to four hours. It requires the 8887 DC Charger, which is the same charger as used for the rechargeable NXT DC Battery. These are sold separately.