Introduction
One of the main tasks of Power Systems is to design and manufacture the main high voltage battery for the solar car each year. At minimum, the goal of the battery is to be able to supply power to the motor and be big enough to have constant full power flow of power from the solar array
Motor
The motor we use, unless we decide to change it this year (highly unlikely) will be the Mitsuba M2096D-III 1WD which is a motor built specifically for powering a solar car.
Requirements:
- Nominal voltage: 96 V
- Nominal power: 2.0 kW
- Nominal current: ~21 A (2000 W/96 V)
Battery Pack Configuration
Individual Cells
- 288 cells total
- Each cell is rated for 5 Ah @ 3.7 V
- Each cell weighs ~6.82 g (~19.6416 kg total) which allows us to stay under regulation weight (20 kg)
Modules
- 32 modules total, 9 cells/module
- Each module is rated for 42 Ah @ 3.7 V
- The modules are connected in parallel to provide more current
Segments
- Three segments total:
- 2x 11 Module Segments
- 1x 10 Module Segments
- The segments are connected in series to provide higher voltage
- Three segments total:
In total, the battery pack has a nominal voltage of 118.4 V and a total capacity of 44.27 Ah.
Early Cell Manufacturing
When we receive the cells from the manufacturer, they normally come bare. This means for us to handle them and use them as batteries safely, it is better to wrap them. See “Battery Cell Wrapping Guide” for information on that process. During this, we assign each cell a number and start the documentation.