Energy storage tailored-test programme for HD hybrid vehicles in a European Project

The development and large diffusion of advanced heavy duty (HD) commercial hybrid vehicles are significantly affected by current economic and technical limitations, which can be improved by advanced highly-efficient and less expensive components, such as alternative storage systems configurations, and drivetrain integration and assembly. In the European Project HCV (Hybrid Commercial Vehicles), different types (urban buses and commercial vans) and generations of HD hybrid vehicles (HEV) have been developed by using various types of storage systems in order to optimize performance and reduce costs in combination with the improvement of other components and assembly processes. In this project, performance and reliability of the storage systems have been carefully characterized in relation to the selected HEV architectures, together with mathematical models of two storage technologies: lithium-ion batteries (Li) and electrochemical capacitors (also named supercapacitors). The adopted approach was to adapt, whenever possible, existing testing procedures (and standards) to the performance characteristics and operating conditions of the storage systems in the project HEVs. In this way, electrical behaviour and abuse situations have been verified in controlled environment in the testing laboratories and design and control recommendations, verified with specifically developed mathematical models, have been transferred to the energy storage suppliers and vehicle manufacturers. All these activities have been carried out in a dedicated Subproject “Energy Storage Systems”, having the participation of energy storage system assemblers (Magna and DimacRed), vehicle manufacturers (Altra-IVECO and Volvo) and testing laboratories (AIT, ENEA, University of Pisa and Volvo). This paper initially describes the electrical and safety test programme tailored to HCV storage systems and specific HD HEVs technical specifications. The second part is dedicated to the reporting a- d analysis of the key experimental results and developed models for Li and supercapacitor cells and modules.