Lithium-ion batteries are an essential component in electric vehicles, however their safety remains a key challenge. This video explores the science behind what happens when batteries are abused and when they fail.
- Mechanical abuse
- Electrical abuse
- Thermal abuse
Starting from how a battery cell works, this presentation from Billy Wu at the Dyson School of Engineering takes you through the basics of how a cell works and how a nail test creates a short circuit.
The high-speed x-ray videos of a cell during a nail test show the cell piercing the layers and the resultant local heating appears as the materials “boil”.
Understand how a cell decomposes and goes into thermal runaway.
Plus a key takeaway from the presentation is “Careful management of lithium-ion batteries are needed”, managing how the cell is charged and discharged can prevent battery fires. The battery management system should manage the state of the battery cells so that they never reach any of these trigger points.
Billy Wu, Dyson School of Engineering
Thermal Runaway
Thermal runaway can be considered at a single cell and thermal propagation at a multi-cell/pack level. Testing at a cell and pack level is a fundamental part of the overall safety sign off.