Fire is one of the concerns for consumers who are considering switching to electric vehicles. In fact, the potential for burning is much smaller when compared to an internal combustion engine.
There is still the risk of electric vehicle batteries that are of concern to electric car manufacturers. To that end, the fire detection and early extinguishing system for the battery is continuously being improved.
Quoted from CarBuzz, two patents were discovered recently at the USPTO related to this hot topic and both were filed by Audi. This patent has a very simple concept.
While simple, it improves the safety of EV batteries with other improvements and can be applied to future Audi e-tron models. Moreover, Audi is one of the manufacturers that has a market in the premium class.
Lithium-ion battery cells can heat and cool down simultaneously during operation. It should run simultaneously on all cells in the battery pack, indicating that all cells share the work equally.
But when a cell operates outside the temperature range, it becomes risky, as volatile chemicals can cause a fire. The cells are connected in parallel in the battery, this problem is often difficult to detect in time.
The first patent solves this problem by identifying and isolating individual battery cells as needed. It is based on information collected by sensors installed in cells and processed with precise mathematical calculations.
Audi’s registered battery control system can detect whether the cell is functioning within a safe temperature and output range. The system will compare the reading with other cells, and can turn off individual cells as needed.
If a problem is detected, the system measures the temperature and output voltage of the now disconnected cell at various intervals.
The information will then be used to calculate whether the faulty cell behavior is a one-time anomaly, or whether there is an actual risk of thermal runaway in the battery.
Battery cells that can extinguish themselves in the event of a fire are still far from reality. The only method to end a battery fire is to starve it of oxygen.
Currently, extinguishing is carried out with water, or with an excessive amount of dry powder extinguishers. But it is very difficult to spray the two extinguishers on the burning battery because it is embedded under the car.
However, Audi has found a solution and has patented it as a battery control system that can detect rising temperatures at the start of a fire.
Fires in EVs are indeed very small compared to ICE, but when they do occur they are very difficult to extinguish. Thanks to Audi’s invention, the notion of prevention is better than cure actually applies.
