Project 1
Design a battery pack for a car roughly 150 Kw with 120 V. Use 3500 mAh 3.6V nominal NMC chemistry cell.
- Design the battery pack configuration.
- Draw the BMS topology for this battery pack.
AIM: To design a battery pack of 150kw with 120v and with given specifications like 3500mah, 3.6v nomial battery.
- Design the battery pack configuration.
Given that, power = 150kw and the voltage of 120v .
Charging Current/Discharging current = 150kw/120v = 1250 amps.= 1250000mA.
No of cells in series required = 120/3.6 =33.3 cells.
verify: if no of cells are 33 then 33*3.6 =118.8v which is not a desired voltage. so, choosing 34 cells would statisfies the voltage.
No of parallel cells to be connected = 1250000/3500 =357.14
verify: If the number is 357 , then 357 * 3500 = 1249500mA which is undesirable, so choosing 358 would satisfiesthe condition.
Therefore the configuration of the battery pack is 358P34S.
Draw the BMS topology for this battery pack.
BMS topology for this model having specifications of 120v, 150kw,1250 amps and for the 34 cells with nomial voltage of 3.6 v
The senory parts to be used are AFE, temperature senor and the current charge /discharge senors.
Fot this heavy pack of 120v , master slave topology is recommended because of 1 AFE carries 17 cells , in that case 2 AFE are used.
For the current senor HALL effect sensor is suiable because of the following advantages like no power loss and can measure high amount of current.
For the temperature senorr, thermistor is used( negative coefficient resistor is prefrable r =1/t)
The proposed BMS design of the battery pack is shown below.
