I would imagine the high voltages would also come with higher potential safety problems. I would imagaine the higher voltages could be an issue in collisions.
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.
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.
In developing hybrid construction equipment, inverters are now using 800 VDC capacitors and the bus takes several minutes to reduce to a voltage that isn't deadly. So, future accidents are highly likely. However, you can't force a new technology without hazards especially when consumers need the new product to perform to the exact same specification as the traditional product.
Trawickim had some interesting observations. The safety feature that disconnects the battery reminds me of the fuel pump shutoff switches on some cars. Even the 12 Volt batteries should have some means of disconnecting. I'm reminded of a car fire that was extingushed only to reignite because of a short in the wiring. The fire extinguishers ran out before the battery did and the car was a total loss. Some industrial machhines have an emergency stop button that kills all the power. If you adjust the nuts and bolts on your battery connectors, you can push them down onto the battery post with a twisting motion and they will lock into place. You can also pull them back off in case of an emergency. If you have side posts, oh well. Pete O.
I realize the article is about the shift to higher voltages in automotive electrical systems, but the "history" portion at the top of the article makes no sense at all, particularly this line: "When the battery alone wasn't powerful enough, engineers augmented it with an alternator and a fan belt."
There was never an automobile that included a battery but provided no means to charge it. Some very early ones had a magneto for the spark, a hand crank for starting, and carbide lamps for headlights, but as soon as the magneto was replaced with a coil-and-points ignition system, a generator was needed to charge the battery. In fact, some early vehicles had generator-driven electric lights before they had an electric starter or a battery.
Also, if one is writing a brief history of automotive voltages, it should be mentioned that all military vehicles since about 1950, and some heavy civilian vehicles throughout that time period, have used 24 volt systems for exactly the same reason higher voltages are being used today -- to reduce the amount of copper needed to carry high power levels.
As far as the safety issues go, I think the only way we're going to get anywhere without prohibitive expense and inconvenience is if we accept that the standard of comparison be "no more dangerous than a tank of gasoline" rather than "can't possibly be hazardous under any circumstances".
Tesla Motors plans to roll out a “compelling, affordable electric car” that will sell for about half the price of its high-profile Model S by the end of 2016, company chairman Elon Musk said last week.
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