Project 2 Thermal modeling of battery pack
Aim:
To model a 10 cell series lithium-ion and compare the performance and thermal effects at various temperatures.
Model:
Explanation:
Components used in the model are
- Battery(Table-Based)
- Current Controlled Source
- Convective Heat Source
- Temperature Source
- Temperature Sensor
- PS Constant
- MUX block
The Series connection is represented via connecting +ve terminal of one cell to - ve terminal of another cell. The 6 lithium cell is connected to the external thermal source which will act as a disturbance.The thermal source will be 293.5K.The MUX block is used to combine the SOC of 10 cells
Case 1) Under Normal Condition:
The PS constant is modeled as 4.2 A as 1C discharge rate and the area is kept as low as 1e-4m^2. The Simulation modeled the full discharge of the Battery.
The battery is fully discharged and the temperature rise as the battery discharges. At the start of the simulation, the temperature is 298.15K and at the end of the simulation is 298.18 K
Case 2 )Changing Area
The area of the convective heat source is changed to 1 m^2.
As the area of conduct increases the temperature decreases significantly.If the area of contact is low the temperature increases. In the above figure, the initial temperature is 298 K and decreases to 294 K and the battery discharges fully. the SOC,yellow line represents SOC of the cell with an external thermal source and SOC decreases fast as compared to other cells in the module.
Case 3)Under the 0.5 C rate and area of 1 m^2.
The PS constant is modeled as 2.9 A as 0.5 C discharge rate and the area is kept as low as 1m^2. The Simulation modeled the full discharge of the Battery.
As the discharge rate is 2.9 A and Battery discharge is up to 70% capacity. The capacity of cell 6 is lower than other remaining cells.As the area of conduct increases the temperature decreases significantly.If the area of contact is low the temperature increases. In the above figure, the initial temperature is 298 K and decreases to 294 K