Safety analysis on the level of a complete road vehicle can be an intricate task. Several methods and tools for safety analysis have been developed by the research community. One such tool developed to bridge the gap between research and industry is Semi-Markov Process (SMP) Tool. In this paper, two approaches for safety analysis utilizing SMP Tool are presented. The holistic approach starts out with a quantitative safety target on a vehicle level to then finally argue whether a proposed system design is safe enough. In the segmented approach, the idea is to follow the development steps of industrial standards, while utilizing SMP Tool for specific tasks within the standard. Specifically the standard ISO 26262 will be under most consideration. Both approaches are applied to a case study of a battery management system for an electrified truck. The segmented approach can avoid some difficulties arising when following ISO 26262 conventionally while keeping the advantage that the standard is utilized to find what qualitative tasks should be performed. The holistic approach has an advantage in that it considers the safety from a vehicle perspective. Moreover, all ambiguity issues in ISO 26262 are avoided.