Project 2 Thermal modeling of battery pack

Assuming LIR18650 Lithium ion cell, the battery pack is created according to the data sheet shown below

For a 10 cell series connection the voltage will be

10*3.7=37 V

The current rating for 10 series connected pack will be 2.6Ah

Therefore a 10 cell series connected LIR 18650 lithium battery pack will have the values as follows

Nominal voltage=37V

Capacity=2.6Ah

Energy=96.2Wh

Simulation model

The battery parameters are provided by double clicking the battery model

The temperature and aging effects are selected to get the plots for temperature and aging effect. We can use any one of the battery from a list of preset batteries to find the response of temperature and aging. as shown below.

To find the temperature and aging effects for a battery parameter other than the batteries listed, we can use an optimisation tool box where we can enter our own battery parameters.

Next enter the initial battery temperature so that the battery model simulates the aging effect and soc according to the temperature provided.

Next the aging parameters are provided in the battery aging space as shown below.

The plots for the above mentioned values are shown below

For a charge and discharge cycle of 2.0Ah capacity the battery parameters are shown for an initial temperature of 20 degree celcius. The temperature increases to 40 degree for every charging and it is understood that the age increases for every single cycle, that is charge and discharge.

The plot for initial cell temperature of 40 degree celcius is shown below

For an initial temperature of 40 degree the cell temperature increases from 40 degree to 55 degrees while discharging and in the first cycle of charging the temperature maintains its 40 degrees temperature that is the initial value for all the charge discharge cycles.