AdvancedTopic 87 of 102Manufacturing, Robotics & Systems
Battery systems
Cells, packs and management systems store energy.
In depth
Li-ion cells (NMC, LFP, NCA) are assembled into modules and packs with a BMS handling state of charge/health, balancing, thermal management and protection. Metrics: energy density (150–270 Wh/kg cell), power, cycle life, safety (thermal runaway), cost. Charging profiles (CC-CV) and ageing mechanisms matter.
Key points
- C-rate
- Depth of discharge
- Second-life use
ExampleLFP packs trade energy density for longer life and safety.
What is Battery systems?
Cells, packs and management systems store energy.
Why is it important to understand battery systems?
Battery systems store energy for vehicles and grids, and the battery management system protects cells and maximises life.
What does a battery management system do?
It monitors voltage, current and temperature, balances cells, limits charge and discharge, and estimates state of charge and health.
Why do cells need balancing?
Small differences in capacity grow over cycles, so the weakest cell limits the pack unless balancing evens them out.
How is Battery systems used in practice?
Typical applications include designing a battery pack for an electric bus with cooling and monitoring, balancing the cell voltages in a pack to avoid overcharge and estimating the range of a car from the battery energy and consumption.
What should I learn before Battery systems?
Study "Electric and hybrid powertrains" first (topic 86 of 102 in Manufacturing, Robotics & Systems). It covers the groundwork this topic builds on.
What are the key points of Battery systems?
C-rate. Depth of discharge. Second-life use.
Can you give an example of Battery systems?
LFP packs trade energy density for longer life and safety.
What comes after Battery systems?
The next topic is "Hydrogen and alternative fuels", which builds directly on this one.
How difficult is Battery systems?
It is classed as Advanced in Manufacturing, Robotics & Systems (topic 87 of 102). It is an advanced topic. It assumes you are comfortable with the intermediate topics in Manufacturing, Robotics & Systems.