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A test center for aging analysis and characterization of Lithium-Ion batteries for automotive applications is optimized by means of a dedicated cell tester. The new power tester offers high current magnitude with fast rise time in order to generate arbitrary charge and discharge waveforms, which are identical to real power net signals in vehicles. Upcoming hybrid and electrical cars show fast current transients due to the implemented power electronics like inverter or DC/DC converter. The various test procedures consider single and coupled effects from current profile, state of charge and temperature. They are simultaneously applied on several cells in order to derive statistical significance. Comprehensive safely functions on both the hardware and the software level ensure proper operation of the complex system.

New high-power loads like Electromagnetic Valve Train (EVT) or "X-by-wire'' systems are the driving forces for the introduction of the 42 V Power Network. These systems show high average power consumption and can cause extreme power transients, which result into a substantial variation of the supply voltage. Such distortions deteriorate the performance of the individual electrical and electronic systems in the car and can stimulate critical interactions between them. An analysis of the system units and the complete network, based on simulations and measurements, must ensure the functionality under all operating conditions. This analysis was performed for a system containing an EVT system, a crankshaft starter-generator, a 36 V battery and an additional energy storage element, together with the wiring harness, and further electrical loads.