Cooling architecture for a vehicle

1. A method of recharging an energy storage system for a vehicle, the energy storage system operable in a charging mode and a discharging mode, the method comprising:

balancing a discharging mode waste power and a discharging mode removal power to independently maintain the energy storage system near a discharging design temperature during the discharging mode via an on-board cooling architecture;

receiving an off-board cooling flow from an off-board cooling system into the on-board cooling architecture of the energy storage system during charging mode, the on-board cooling architecture is configured to receive the off-board cooling flow wherein the on-board cooling architecture comprises a network of on-board passages proximate to at least portions of the energy storage system, the off-board cooling flow communicates with the energy storage system via the network of on-board passages; and

distributing the off-board cooling flow to maintain the energy storage system near a charging design temperature through a balance of a charging mode waste power and a charging mode removal power.

2. The method as recited in claim 1 , wherein balancing the discharging mode waste power and the discharging mode removal power comprises sizing a heat exchanger for a discharging mode ambient temperature.

3. The method as recited in claim 1 , wherein a peak charging design temperature is the maximum temperature at which the energy storage system operates when the charging mode waste power is at a maximum.

4. The method as recited in claim 1 , wherein the on-board cooling architecture is configured to receive the off-board cooling flow to replenish and renew the coolant.

5. The method as recited in claim 1 , wherein the on-board cooling architecture rejects waste heat into a fan stream of a hybrid electric aircraft for thrust recovery.

6. A vehicle, comprising:

an energy storage system configured to operate in both a charging mode and a discharging mode;

an on-board cooling architecture configured to receive an off-board cooling flow and in fluid communication with the energy storage system during the charging mode of the energy storage system such that the off-board cooling flow maintains the energy storage system near a charging design temperature through a balance of a charging mode waste power and a charging mode removal power, the on-board cooling architecture configured to maintain the energy storage system near a discharging design temperature during the discharging mode without the use of the off-board cooling flow.

7. The vehicle as recited in claim 6 , wherein the on-board cooling architecture is configured to maintain the energy storage system near a peak charging design temperature, and the charging mode waste power is greater than the discharging mode maximum removal power while the on-board cooling architecture uses the off-board cooling flow during charging.

8. The vehicle as recited in claim 7 , wherein the on-board cooling architecture is configured such that without the use of the off-board cooling flow, if a charging mode ambient temperature equals a discharging mode ambient temperature, then the charging mode removal power equals the discharging mode removal power.

9. The vehicle as recited in claim 8 , wherein the on-board cooling architecture is configured such that without the use of the off-board cooling flow, if a charging mode ambient temperature is greater than a discharging mode ambient temperature, and a charging mode ambient air density is greater than a discharging mode ambient air density, then the charging mode removal power is less than the discharging mode maximum removal power.

10. The vehicle as recited in claim 7 , wherein the on-board cooling architecture is configured such that with the use of the off-board cooling flow, if a charging mode ambient temperature is greater than a discharging mode ambient temperature, then the charging mode removal power is greater than the discharging mode maximum removal power.

11. The vehicle as recited in claim 10 , wherein the on-board cooling architecture is configured such that with the use of the off-board cooling flow, if a discharging mode time period is greater than a charging mode time period, then the charging mode waste power is greater than the discharging mode waste power, and the charging mode removal power is greater than the discharging mode removal power.

12. The vehicle as recited in claim 6 , wherein the on-board cooling architecture is configured to maintain the energy storage system near a discharging design temperature without the use of the off-board cooling flow.

13. The vehicle as recited in claim 6 , wherein the on-board cooling architecture is configured to balance the discharging mode waste power and the discharging mode removal power with a heat exchanger sized for a discharging mode ambient temperature and a discharging efficiency of the energy storage system.

14. The vehicle as recited in claim 6 , wherein the on-board cooling architecture is configured to balance the charging mode waste power and the charging mode removal power with a heat exchanger configured to receive the off-board cooling flow and sized for a charging efficiency of the energy storage system.

15. The vehicle as recited in claim 6 , wherein a peak charging design temperature is the maximum temperature that the energy storage system should operate when charging mode waste power is at a maximum.

16. The vehicle as recited in claim 6 , wherein a peak charging design temperature equals the discharging design temperature.

17. The vehicle as recited in claim 6 , wherein the on-board cooling architecture is configured to receive an off-board cooling flow, the on-board cooling architecture comprises a heat exchanger configured to maintain the energy storage system near a discharging design temperature without the off-board cooling flow and to maintain the energy storage system near a peak charging design temperature with the off-board cooling flow.

18. The vehicle as recited in claim 17 , wherein the on-board cooling architecture comprises a controller configured to adjust at least one of a coolant temperature and a coolant flow rate from an onboard heat exchanger and an offboard heat exchanger.

19. The vehicle as recited in claim 6 , wherein the on-board cooling architecture is configured to receive the off-board cooling flow to replenish and renew the coolant.

20. The vehicle as recited in claim 6 , wherein the on-board cooling architecture rejects waste heat into a fan stream of a hybrid electric aircraft for thrust recovery.

21. A hybrid electric aircraft, comprising:

an energy storage system configured to operate in both a charging mode and a discharging mode;

means for receiving an off-board cooling flow into an on-board cooling architecture in fluid communication with the energy storage system during the charging mode of the energy storage system such that the off-board cooling flow maintains the energy storage system near a charging design temperature through a balance of a charging mode waste power and a charging mode removal power, the on-board cooling architecture configured to maintain the energy storage system near a discharging design temperature during the discharging mode without the use of the off-board cooling flow.

22. The hybrid electric aircraft as recited in claim 21 , wherein the means for receiving an off-board cooling flow into the energy storage system comprises a heat exchanger configured to independently maintain the energy storage system near a discharging design temperature without the use of the off-board cooling flow, and to maintain the energy storage system near a peak charging design temperature with the use of the off-board cooling flow.

23. The vehicle as recited in claim 21 , wherein the on-board cooling architecture is configured to receive the off-board cooling flow to replenish and renew the coolant.