There has been little published research critically examining the mechanical integration of battery systems within either EVs or HEVs. Many of the existing Standards are designed to validate the fail safe function of the battery pack as opposed to assessing the mechanical durability of the complete system. If excessive vehicle warranty claims are to be avoided it is important that engineers tasked with the design of the battery installation properly understand the magnitude and frequency of the vibration inputs that the battery will be exposed too during the vehicle's predicted life. The vibration characteristics of three different commercially available EVs have been experimentally evaluated over a wide range of different road surface conditions. For each vehicle, a durability profile has been sequenced to emulate the vibration energy that the battery pack may be exposed too during a representative 100,000 miles service life. The primary conclusions from the results presented are that the battery packs may well be exposed to vibration loads outside the current evaluation range of existing Standards.