A team from the Graz University of Technology, as part of the project dubbed “SafeBattery”, has been researching the behavior of lithium batteries in electric cars under shock loads for the past four years.
The researchers, for example, know the performance of the new battery cells, although they had not inquired about the entire life cycle of the battery. Thus, they studied and analyzed the different scenarios that a certain battery can experience throughout its useful life: vibrations, strong accelerations caused by parking shocks, constant charging and discharging and, in addition, serious accidents.
With the help of simulation models, calculation methods and crash tests, the researchers were able to determine that both vibrations and accelerations hardly affect the behavior of the batteries . But they did see more significant electrical and mechanical changes as a result of the constant charging and discharging of the battery.
Battery cells aged in this way have greater rigidity under mechanical load, but these types of changes do not necessarily mean that they become more dangerous over time. On the contrary, the sum of the different influences makes them safer over time, since they also lose electrical energy.
Thus, as there is a reduced energy potential, something that is commonly found in older electric vehicle batteries, it reduces the risk of accidental fires, increasing their safety.
Benefits for the automotive industry
Thanks to the results of the research, manufacturers now know what to expect from a battery cell, which offers the possibility of developing designs that help save material and achieve, above all, greater efficiency.
In fact, until now, the battery was installed in such a way that deformations could be ruled out in all unimaginable scenarios. However, now, manufacturers can make better use of the installation space . While, in addition, the security associated with the checks of a new cell are valid throughout the useful life of the battery.
A second life for electric vehicle batteries?
When it comes to the timeline of battery life, the “SafeBattery” consortium now goes one step further. And it is that in the COMET SafeLib project, recently launched, changes in traction batteries for electric vehicles are being examined in greater detail together with other partners, such as Mercedes or Fronius, in order to develop safety factors for their later use .
And it is that although the batteries used with a power capacity of 80 percent are no longer suitable for use in electric vehicles, they do tend to be suitable for stationary energy storage.
Due to this, the team of scientists pursues the objective of defining parameters for the subsequent use of those batteries that have been discarded. And what is even more interesting: developing designs that help achieve greater efficiency and save material .
