With improvement, I was referring to the complexity of cutting someone out of a Tesla and all the no-cut zones that could electrocute passengers, emergency responders, even guys towing wrecks. You're right, there is no real safety record yet.
As an electrical engineer with spacecraft experience, I can say that a car like the Model S isn't likely to electrocute anyone. While extracting someone from a wreck, emergency workers use tools like the "jaws of life", strong metal pliers meant to quickly snip a car's body apart.
When a tool like this cuts into an electric car, if it should slice through a power cable, in most cases the tool would short the cable to the car's chassis, thus grounding it and tripping the safety links that are integral to the battery pack. This means the car will become inoperative, but it doesn't mean anyone will get electrocuted.
I think the above will be the outcome in the vast majority of cases. Compare this to the plight of someone sitting in a wrecked gasoline-fueled car.
Much of the video is concerned with instructing responders how to cut around components that may remain electrified such as the converter and capacitors which, in Tesla's own words, present a "serious hazard of shock" because "they can release up to 400 volts in just an instant."
As I understand it it's done on a per-model basis, but that wont really work as an increasing number of electric car models end up on the roads. I'm not sure if this is done all over the state/country, or if it's the one local dealer being friendly with the local emergency services.
However, there is definitely a risk here, albeit what appears to be a manageable one. Perhaps there could be some use in building volt meters that glow into gloves for emergency responders to help mitigate some of the risk.
400V can overcome your body's resistance no problem. And obviously an EV has a crap ton of amperage as well.
I would've assumed the production of specialised tools for electric cars would be a priority once they become popular.
The problem is, we're cutting through and crushing various bits of the car that weren't really designed to be indiscriminately cut into (which is why training is so important).
Both rescuers and victims have been seriously injured and killed when extrication activities turned potential energy stored in the car into kinetic energy. Air bag deployment systems, seat belt pretensioners, even the little hydraulic tubes that hold your trunk open and be extremely dangerous if their energy is released in an uncontrolled way.
So you can understand why we're a little leery of 85 kWh of potential energy sitting under the car...
Here's an example of airbags being deployed when the SRS controller was crushed with a hydraulic spreading tool.
https://www.youtube.com/watch?v=yDSksTztHJk
Two firefighters were injured in that incident (one of them seriously).
A 40 litre petrol tank holds about 380 kWh though.
The issues involved are also very different. A tank of gas is actually a very stable thing. Barring a puncture, there's not much you can do to a gas tank to make it do bad things.
Cutting a gas line is no major concern. Shorting a high voltage/high current power line to the frame of the vehicle is putting a lot of trust in the batteries failsafes (that trust is almost certainly justified, but with a track record measured in years, not decades, you'll forgive us for being a little paranoid...).
edit - I said it earlier somewhere else, but EMT gloves with built in glowy multimeters might be a really good plan.
double edit - if you think this is a good plan, feel free to nick it.
It wouldn't make sense for it to be dependent on a link from the airbag sensors, it would have to be local to the power plant.