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Comment by xondono | Hacker News Reader

As someone who both tinkers with cars and bikes, and has designed and tested drives for various kinds of electric motors (brushless, AC,...):

- The perception that people have of how dangerous gasoline is, is greatly over exaggerated.

- The perception that people have of how dangerous high voltage drives and lithium batteries are, is greatly under exaggerated.

With 15 minutes I can give you enoguh pointers to have you tinkering your gas engine safely.

No such confort exists if you are going to tinker with your EV

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You're basically sitting on top of a giant bomb in an EV when it's fully charged. Shoot a bullet through a full gas tank, and nothing will happen. Shoot a bullet through an EV battery pack and it will burn to the ground. Liquid electrolytes are the real problem here, not battery tech as a whole. Fortunately solid state batteries are only a few years out, and that will totally change the safety equation.

I'm not sure that bomb is the right analogy. Maybe thermite would be a better analog? EVs will burn long and hot (though not as hot as some imagine), but do not tend to be explosive.

They may not explode but contacting a 400V bus that can dump ~1200 amps produces a similar effect on the human body.

You do realise the safety profile of a large tank of petrol right?

It's actually much better than Hollywood would have you believe: a shot fuel tank will not explode.

http://prometheus-fs.co.uk/articles/hollywood-lies-to-you/

A demonstration of the safety benefits of solid-state batteries:

https://www.youtube.com/watch?v=m9-cNNYb1Ik

I agree with you in principle, but I hope that things will change as people develop an awareness of things.

There are several dozen other companies that manufacture electric cars, and they will sell you shop manuals to service things, including the main battery pack.

As an intellectual exercise, searching for "leaf evb pdf" might lead to manufacturer procedures for diagnosing and servicing an electric vehicle battery system (with safety recommendations).

I know this isn't tinkering per se, but maybe tesla will someday do the same.

I’m not saying the’re unserviceable, just that the amount of training and safety concerns are a whole other level.

Even well trained engineers get zapped sometimes with capacitors that should be discharged by actually aren’t.

Power electronics can be very unintuitive because most people are used to tinker first with low voltage electronics like PCs, arduinos and things like that.

I do agree with you.

And I would go further to mention magnetism. I think the model S with its ac motor might not rely on magnets, but the model 3 and other cars probably have powerful permanent magnets that require a completely different kind of caution.

I just hope we can forge a path now rather than later. We need future scientists and engineers to be safe but creative.

Yes, and safety protocols have existed for a long time. My Prius has a nastily powerful battery inside it, and I can work on it all by myself, since I don't open the pack, usually, and I know how to disconnect it. It's remarkably easy.

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