In the long term emission-free battery-electric or hydrogen-operated fuel cells will be the most effective system in short-haul mobility. At the same time delays could take place for the benefit of the pure batteryoperated drive through advances in the area of battery technology in the future. In accordance with the electromobility government programme, electromobility is an important element of climate-conscious energy and transport policy. The energy storage system thus illustrates a key technology for electromobility. The aim of both »PRIMO« projects is to develop competitive and innovative energy storage concepts for local public transport and special vehicle use.
With its examinations into prismatic lithium cells for the local public transport drive train, the »PRIMO« development project constitutes the starting point for the »PRIMO« II project »Development of modular, distributed energy storage systems and cost-optimised manufacturing techniques for use in the local public transport sector«. Through this, an international comparison of technological status by benchmarking prismatic lithium cells for the electrification of e-bus drive trains was carried out. The choice of prismatic cell technology for the construction of the distributed, modular energy storage systems was made on the basis of the preliminary standard DIN SPEC 9152 for lithium. The cells conforming to the preliminary standard will be used in future by the automotive industry for electrification in passenger vehicles and, cost-optimised, will be available in high volumes.
The benchmarking results serve to identify lithium cells suitable for application, which form the basis for the rough construction of »sub-modules« in lightweight design. The »sub-module concept« developed is the departure point for the construction of distributed high-voltage energy storage systems in local public transport.
The detailed development of the overall system is currently taking place in the ongoing »PRIMO« II development project. The estimated development should lead to innovative distributed energy storage solutions, which can be used for a flexible, application-specific design in the local public transport area. The focus of development is the overall system including the necessary charging technology. Thus an entire system development will be run for electrification in the local public transport area, whose efficiency in relation to energy supply and consumption can be significantly raised by individual coordinated components at system level and offered to the operator as an independent overall concept. Energy storage systems > 400 V necessary for the electrification of the drive train in local public transport thereby provide a good starting point. Current requirements for the electrification of the drive train for electric busses are approx. 650 V. For the system construction lightweight components are being evaluated, where the design of this kind of multi-functionally designed sub-module allows for integration of different prismatic cells.
Apart from the development of these distributed, modular energy storage systems, new, innovative production and process technologies to prove economic viability are also being developed.
03EM0702 & 03EM0703