A collapsible hydraulicaliy operated ambulance cot having a support frame, a wheeled base, a support mechanism disposed therebetween, and a lift system for hydraulicaliy moving the upper frame relative to the lower frame is disclosed. The lift system permits a single attendant to raise the cot from a lowered position to a raised position, and an infinite number of positions therebetween, and to raise the wheeled base relative to the support frame to situate the cot onto an elevated surface such as the transport deck of an ambulance. A manual override is also provided to conserve battery powerand as a back-up in no-power situations. It is to be appreciated that the above described manual override mode may be used when raising or lowering the cot without power assist, dropping the undercarriage when unloading from a vehicle, and lifting the undercarriage when loading into a vehicle. A charging system for recharging a battery of an electro-hydraulically powered lift ambulance cot with an electrical system of an emergency vehicle is also disclosed.