The aim of the project „JOSPEL“ is to increase the efficiency, and thus the driving range, of electric vehicles. The focus of this project is the conditioning and the intelligent controlling of the energy flows. The Battery Technology Group at Fraunhofer ISE has the task of developing a battery system with an advantageous thermal management. The target is to decrease the amount of energy used for conditioning the battery cells, yet at the same time to increase the cells’ lifetime and ultimately that of the electric vehicle.
In the European research project JOSPEL, Fraunhofer ISE, together with its partners from industry, is commissioned to develop and build a battery system that ensures a higher efficiency as well as a longer lifetime. Since the two criteria are opposing at times, a simulation model was developed to calculate the effect of the thermal management on the cell aging. In the models, different operating strategies could be evaluated: thermal pre-conditioning of the cells prior to driving, various solutions for passively and actively cooling the battery system, etc. Thus, the ideal operating parameters for a long lifetime and an optimized system layout could be determined. In order to correctly simulate the battery cell behavior in the developed model, numerous tests were carried out first. Battery cells were measured in the laboratory under different environmental conditions (e.g. temperature, pressure, level of current, depth of discharge, etc.) and tested over many years.
In the last phase of the project, the battery system developed is going to be built and measured in operation. Thus, the real effect of the system and operational management optimizations will be proven.