Week 8 Multi cell Battery Pack

Need of Cell battery Pack:

Single cell, cannot provide the required tractive force effort to the EV so the combination of the cells need to be connect to series and parallel for voltage and current boosting respectively.

Weakest Cell:

Fig: Assumtion of that all cells are connected in series.

During Charging the weakest cell, cell 2 is charges fast and rest of the cells are not charged further with BMS trigger the charging circuit. So cell 4 is weakest cell of the string

If the string is discharging then the cell 4 discharges fast, so other cells are not utilize its capacity.

Solution

Instead of connected series string to parallel for reaching the total capacity of EV battery pack. The connetions are changed to parallel string to series connected strings. The weakest cell is balancing among only that parallel string.

Conclusion:

The report presents the effect of weak cell in the battery string.