Electrical Design of Battery Packs - II — Lesson 2

This lesson covers the critical aspects of conductor material selection and design. It delves into the two crucial aspects of any current conducting path: thermal and electrical. The lesson explains how the resistance of a conductor depends on the material property and physical dimensions. It also discusses how resistivity is a function of temperature, affecting the current carrying capacity of a conductor. The lesson further elaborates on the impact of temperature on resistivity and heat generation, and how these factors limit the current carrying capacity of a conductor. It also provides an illustrative example of bus bar sizing for a two-wheeler electric vehicle, demonstrating how to determine the thickness of the bus bar and the voltage drop across it.

Video Highlights

00:21 - Design criteria for battery packs
07:45 - Busbar sizing problem and solution
10:02 - How to calculate the dimensions of a bus bar
12:21 - Short circuit scenarios
16:20 - Mechanical considerations for designing battery pack
19:47 - Conductor insulation selection
23:09 - Busbar sizing problem and solution

Key Takeaways

- The resistance of a conductor depends on the material property and physical dimensions.
- Resistivity is a function of temperature, which affects the current carrying capacity of a conductor.
- The current carrying capacity of a conductor is limited by the maximum acceptable temperature.
- The heat generated by a conductor should always be less than the capacity of heat removal by natural convection.
- The thickness of a conductor can be determined using iterative solutions based on design temperature and other conditions.