Material handling apparatus for delivering or retrieving items

A delivery vehicle operable with a material handling system having a first plurality of destination areas and a second plurality of destination areas with a gap between the first and second plurality of destination areas, a first horizontal track adjacent the first plurality of destination areas and a second horizontal track adjacent the second plurality of destination areas, wherein the gap is part of an aisle in which the delivery vehicles are displaced vertically and horizontally, wherein the delivery vehicle comprises:

• a first wheel engageable with the first horizontal track to convey the vehicle in the aisle in a first horizontal direction;
• a second wheel engageable with the second horizontal track to convey the vehicle in the aisle in the first horizontal direction;
• a motor operable to drive the first and second wheels;
• a transfer mechanism comprising one or more conveyor belts forming a horizontal surface for receiving an item to be conveyed to one of the destination areas wherein the transfer mechanism is configured to displace items in a second horizontal direction that is transverse the first horizontal direction;
• a rechargeable power source configured to provide power for the motor and the transfer mechanism;
• an electrical contact for contacting a charging rail of the material handling system to recharge the rechargeable power source as the delivery vehicle travels along a path forming a vertical loop in the aisle.