Behaviour and ageing of batteries under real-world usage conditions
The research of Eco7 in the field of energy storage covers the characterisation and modelling of batteries, their usage, and their ageing. Battery usage in transport applications vary greatly according to the type of vehicle, road, driver, and climate. As a result, the behaviour and ageing of batteries used in these applications remain difficult to explain and predict, especially since both change from one technology to another. Eco7’s research activities in this field are based on an experimental approach.
The first step is to understand how the batteries are used and characterise the subsequent applied stresses (thermal, electrical, etc). This is achieved by collecting databases containing data from instrumented vehicles (CROME project). In addition, an analysis and classification tool has been developed to determine the representative current pulses or a particular use case, qualitatively compare among different use cases, and construct simplified representative cycles.
We have also developed test protocols and data-mining tools that enable us to characterise and model batteries. The resulting models are validated with usage profiles obtained from instrumented vehicles measurements (either on road or on a chassis dynamo). These battery models are included in VEHLIB (Vehicle Hybrid Library).
Eco7 was involved in two national projects to study battery ageing. The first (SIMSTOCK) focused on cyclic ageing of batteries and the second (SIMCAL) investigated calendar ageing of batteries. Eco7 also participated in the MOBICUS project to explore the relationship between these two ageing modes and will enable us to understand battery ageing under real-world usage conditions.
Finally, Eco7 is a member of the COMUTES2 consortium associating partners from the above-mentioned projects.