Comment by aetherspawn | Hacker News Reader

Comment by aetherspawn | Hacker News Reader

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Electric cars are notoriously unreliable because there are just that many things that can go wrong. For example, a battery pack on average will monitor about 400 temperatures and perhaps 200 voltages. Its inherent design means that it undergoes many thermal cycles, has thousands of fasteners and up to a hundred switching circuity components inside various isolated power supplies. The deviation of any parameter from normal requires an immediate shutoff at risk of a lithium fire that cannot be extinguished.

You could not even imagine the amount of engineering that goes into making sure the fasteners are positive locked in a redundant manner, whilst preloaded against temperature change, without breaking isolation.

Yet, a Tesla is, in general, relatively reliable. Maximum props to them on a job well done.

Ehh, but fundamentally its just 1-2 motors and a big battery.

No alternator, fuel injection, radiator fluid, oil, pistons, spark plugs, fuel pumps, exhaust, manifolds, shafts, rods, gears, blowers, turbos/superchargers, catalytic converters, etc.

Not saying it's easy as described with unstable lithium chemistry, and its own heat dissapation problems, but MECHANICALLY it is fundamentally simple.

Yeah, except that we have literally a century of experience building all of above, but only decade or so of building huge automotive lithium batteries. It's "just" a battery, but at the same time it's hideously complex device where a lot of things can go wrong.

You don't actually have to measure individual cell temperatures and voltages. A thousand fasteners is nothing special, and you don't need to have circuitry on each cell either. You're making batteries out to be much more complex than they actually are.

I am not, and it is necessary to measure the temperature of the batteries in at least some locality, as batteries can short out and go into thermal runaway. Although their construction can avoid a full battery pack fire, if you don't shut down the tractive system immediately you will run current through them and charge them negatively. Then you will get a fire from surrounding cells.

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