(b) The design objectives for the vehicle are shown in the table below, along with key...

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(b) The design objectives for the vehicle are shown in the table below, along with key characteristics of a pouch cell that has been selected for the battery pack. Design a battery pack configuration (number of cells in series/parallel) to satisfy the requirements with the minimum number of cells per pack. Vehicle Requirement Power: 120kW Maximum DC voltage: 440V Minimum DC voltage: 220V Energy (min.): 41 kWh Battery Cell Data Usable voltage range: 2.8 - 4.1 V Charge capacity: 26Ah Energy capacity: 94Wh Maximum C-rate: 4C (c) When charging there is no airflow. As a result the maximum C-rate which can be achieved without encountering thermal management problems is 2C. For the pack configuration proposed in (b) calculate the charging power which the battery can accept from 0% SOC, and the peak charging power it is capable of. (d) The charging power needs to be increased, and it is suggested that increasing number of cells would help. If one additional parallel string were added to the design in (b) and no other changes made, calculate the proportion in which the loss density (losses per cell) would change for the same battery power. Comment on the pros and cons of this as a solution to the thermal management issue. (b) The design objectives for the vehicle are shown in the table below, along with key characteristics of a pouch cell that has been selected for the battery pack. Design a battery pack configuration (number of cells in series/parallel) to satisfy the requirements with the minimum number of cells per pack. Vehicle Requirement Power: 120kW Maximum DC voltage: 440V Minimum DC voltage: 220V Energy (min.): 41 kWh Battery Cell Data Usable voltage range: 2.8 - 4.1 V Charge capacity: 26Ah Energy capacity: 94Wh Maximum C-rate: 4C (c) When charging there is no airflow. As a result the maximum C-rate which can be achieved without encountering thermal management problems is 2C. For the pack configuration proposed in (b) calculate the charging power which the battery can accept from 0% SOC, and the peak charging power it is capable of. (d) The charging power needs to be increased, and it is suggested that increasing number of cells would help. If one additional parallel string were added to the design in (b) and no other changes made, calculate the proportion in which the loss density (losses per cell) would change for the same battery power. Comment on the pros and cons of this as a solution to the thermal management issue.