Project 1

ANSWER : let us consider the cell with

nominal voltage =3.6 v

capacity = 3500mAh=3.5Ah

convert the battery capacity 150kw to Ah

by the help of the power formula which is

P=VI

here the voltage given is 120v

=150*1000=120 *I

I=15000/120 = 1250Ah

a) series :

Number of cell in series = required voltage /Nominal voltage of the cell

Number of cell in series = 120/3.6=33.33

now we will round off to lower value and higher value so that 33 and 34 these are going to be the two no on which we will carry on our calculation

two cases we will take

case 1	case2
(no of cells in series will be 33)	(no of cells in series will be 34)
nominal vol*33 3.6*33=118.8v maxvol*33 4.2*33=138.6v min vol*33 2.7*33=89.1v	nominal vol*34 3.6*34=122.4 max vol*34 4.2*34=142.8v min vol*34 2.7*34=91.8v

it is better more voltage so we will choose the higher value for the no of cells

the no of cell in series is 34

the output voltage is about 122v

BMS topology:

As there are about 34 cells in series in the battery pack, we have to use Master-Slave topology as the BMS topology in which Master/slave is a model of communication for hardware devices where one device has unidirectional control over one or more devices. This is often used in the electronic hardware space where one device acts as the controller, whereas the other devices are the ones being controlled.

The total battery pack is made of sub-battery packs so controlling and manufacturing will be easy.

as we have 34 no of cells in series so we would be requiring two slaves each slave having 18 cells