The cables in question will be exposed to temperature extremes (0-100 F in ambient swing alone). The insulation of these cables will have to stand up to that, as well as engine heat, and do so for a design life of a decade or more. No cracking or degradation of the insulation will be acceptable.
Your imagination is correct, Rob. Even in non-accident situations, the use of higher voltages adds an additional layer of engineering, as Chuck points out, in the form of isolators. Supposedly, a high-voltage isolator fault was at issue in the recent Fisker Karma car which "died" when it was brought out to Consumer Reports's test track.
A half century ago, cars were still built by people, not robots. Even on some of the countryís longest assembly lines, human workers installed windows, doors, hoods, engines, windshields, and batteries, with no robotic aid.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.