Consideration of damaging frequency ranges of structural excitation for testing large battery packs in Battery Electric Vehicles (BEV)

Abstract

Realistic vibration testing of large floor mounted Battery Pack, sometimes called Rechargeable Energy Storage Systems (RESS), for Batterie Electric Vehicles (BEV) is important for developing safe new battery structures. On the other hand, the requirements for realistic replications of worst-case environments in a lab usually demand costly and complex infrastructure. A key factor to the quality of environment replication and an important cost driver due to the increasing complexity is the needed frequency range the equipment must be able to replicate. The contribution analyzes data from a first pre-test campaign to demonstrate a feasible process of deriving frequency band requirements for the test equipment. The key method used here is the Fatigue Damage Spectrum (FDS) to analyze the potential damage a vibration could cause in certain failure mechanism of interest, particularly “weighted” by the corresponding double-logarithmic dependance of stress magnitude over occurring load cycles. This enables a good assessment of how much damage could be induced in certain frequency ranges for a well justified and cost-effective choice on the needed test equipment.