Batteries and the BMS

Fast Track:

The batteries were the most difficult component in my build.  Batteries are one of two components that are essential in an electric car.  The other of course is the motor. 

The five Tesla S batteries in Maggie are fitted into two aluminum boxes.  There two batteries are in one box and three in another; all five are wired in series.  Their juice is carried to the front of the car through pipes under the body.

Juice flows into the batteries from the charger; juice flows out of the batteries to the motor.

Left to right i the picture, first is the black high voltage switch.  This switch will be connected to the positive side of the three batteries which are connected in series.  You can see the right side lead of the switch connected to a 2/0 cable which goes out of the box headed for the motor.

Next, the white tube is a high voltage fuse. The lower side of the fuse will be connected to the negative side of the batteries in this box.  The the upper fuse connection is connected to a HV cable going out to the 2-battery box and will be connected to the plus side of the 2-battery box.. 

The HV cable in the bottom left of the picture is attached to the master switch.  This cable will be attached to the "positive terminal in the 3-battery group.

Finally, the white square label is on the Battery Management System - the BMSC. 

The BMSC provides a serial connection to a laptop using a terminal emulator. 

The above report is from a serial connection to the BMSC and shows the five batteries, six parallel sections at a time.