Project 2 Thermal modeling of battery pack

In this Project I have to do Battery Pack with 10 number of cells connected series along with I have to connect Thermal sensor

to check the Battery Temperature on Different Temperatures.

To Do a Simulink Model we require some Blocks

1)Signal Builder Block

By Using This Block I can Fed details in Time Elapse from 0 to 1369 Seconds.I created a new custom signal in that Time values

are from 0 to 1369 and Y values are som random numbers.I took this data from Below link

https://docs.google.com/spreadsheets/d/1TVU8wMo_FKpm1wG-PmAZsY2hAMNDFpkse9k9FrclCAE/edit#gid=0

2)Battery(Table_based)

We require an 1 SOC and 1 Thermal Port to get this we require some changes in the block.The above block is default one.

I made some chages in block as Expose SOC to Yes.Thermal Port form Omit to Model and changed value to 100.

3)Controlled current source

4)Current Sensor

5)Voltage Sensor

6)Convective Heat Transfer

7)Temperature sensor

8)Temperature Source

9)Thermal Reference

10)Electrical Reference

11)Solver configuration

12)2 constant blocks and divide,sum blocks

These are the blocks we used to complete simulink Model

Thermal Modeling Battery Pack:

At first I took signal builder block as provided above link from that link I used data.After submitting this data I got this type of signal

From this signal builder block I connected to controlled current source from that to current sensor on one side and another side a 10 number of cell series connected.voltage sensor is connected to get voltage.Possitive side of voltage is connected to positive side of cell.In the cell thermal port is open the same thermal port is connected to series.The same thermal port is connected to the thermal sensor to get temperature as output another side of connected to Thermal reference.convective heat transfer means that we can provide gap between cell to cell.I took convective heat transfer as default at first.

This convective heat Transfer is connected to Thermal Source which means that giving initial Temperature.

From the current sensor to integrator from integrator we divide with 28*3600 (battery capacity is 28Ah now can be converted into ampere seconds) from that connected to sum block from that we subtract to 1 then we got SOC.

All these SOC,Voltage,Current,TEMP are connected to scope.

As we can see Above graph Current is similar to UDDS cycle data.As Current is Max upto 8.

From SOC graph battery percentage is decreased from 100 to 99.2%.we can see that when current decreases Soc is increasing because of Regn Braking.

From Temp graph Temperature is increasing slowly.

From voltage Max voltage is 42.3 minimum voltage is 41.9.

Now we will change different values from Temperature source and convective heat transfer to check different results.

Now I changed Temp source Temperature value is 350K and Increased Area from 1e-4 to 1

Now lets see Results.

Current,Voltage,SOC is same as Before But Temperature is raised upto 350K after that Temperature is constant.because as we increased area between cells due to that cells gets cool down.

Noow I can further increase Area and coefficient.Lets see result

I changed convective heat transfer Area parameter to 50 and Heat transfer co-efficient parameter to 1.

I changed temperature to 200K.

Lets check result

As we can see that all three graphs are not changing except Temperature is changing (compare to previous graphs) at 50 seconds temperature falls down due to more area between each cell.

Conclusion:

I Modeled Battery pack of 10 cells connected in series.I checked different temperatures 298.15K,350K,200K and area aswell By doing this I get to know that if we can increase area between cells we can get lowest Temperature.