Dual+ Spare Battery Brick 180WhThe Dual+ Battery system offers modular battery upgrades.The 180 Wh battery can be paired with another 90 Wh brick or the more powerful 180 Wh brick. The Dual+Battery system uses two separate bricks that combine the motors autonomy.The 180Wh battery will provide up to 3,5 hours of motor operation.Charging time: 2 hoursAll SipaBoards batteries use aerospace grade battery cells, ultrasonic welding and is encased in a special fire retardant housing. Up to 4 hours battery lifeExpandable battery packs offer more range and autonomy.