Underbody unit for a motor vehicle

An underbody unit for reinforcing a motor vehicle body of a motor vehicle between a front axle and a rear axle, comprising:

• a floor body that is connectable to the motor vehicle body, for dissipating static and/or dynamic loads of the motor vehicle body;
• reinforcing ribs protruding up from the floor body and defining receiving pockets for receiving at least one battery cell unit of a traction battery for driving the motor vehicle as a hybrid vehicle and/or as a purely electric vehicle;
• first and second inlets for accommodating in-flows of a liquid cooling medium into the floor body;
• first and second outlets for accommodating outflows of the liquid cooling medium from the floor body;
• a low temperature cooler for cooling the liquid cooling medium;
• a first valve selectively switchable between a first position where the first valve causes the liquid cooling medium to flow directly from the first outlet to the first inlet and a second position where the first valve causes the liquid cooling medium to flow from the first outlet to the first inlet via the low temperature cooler;
• a heat exchanger accommodating a flow of the liquid cooling medium from the second outlet to the second inlet;
• and
• a refrigerating circuit including a second valve for selectively permitting or interrupting a flow of a coolant through the heat exchanger, whereby the first and second valves are operated for selectively causing the liquid cooling medium to be cooled by both the low temperature cooler and the heat exchanger, or by a selected one of the low temperature cooler and the heat exchanger or by neither the low temperature cooler or the heat exchanger in accordance with cooling needs of the traction battery.