61–70 of 213 posts
I still think road charging would be cool and obviously the fastest if we never have to stop anyways. Couldn’t work everywhere in the US probably but I can dream.
Trains and buses do it already where I live.
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How would they do w/o the current subsidies?
Oil would be pretty much the same. Ag would be a chaotic disaster. The subsidies for ag were written in blood based on the need to smooth the natural forces of extreme cyclic market fluctuations that affect all inelastic commodities. But a society cannot afford those cycles to play out for their food supply. Prices need to be stable and we need a slight oversupply of staples to be robust rather than perfectly efficie…
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Like Henry Ford tried on the Model T: The Model T was offered in three fuels: Gasoline, Electric, and Alcohol. It only took I think less than a year to make it Gasoline only.
Is there any universe where we go the electric route instead of gasoline back then? I imagine the range was nothing
So basically, remove isolation transformers, and feed the line voltage (7.2kV or so) through a simple buck converter into the car. Instead of galvanic isolation, use redundant ground connectors that are monitored for continuity. I'm not sure I agree with this. It puts too much responsibility onto the EVSE side, as it'll have to be able to break the fault if it happens. If something like emergency pyro disconnects are…
> as it'll have to be able to break the fault if it happens Are you talking about the case where both of the ground wires fail while charging? If either is non-functional when charging starts, it disallows charging. If one fails during charging, charging disconnects.
The charger tries to interrupt the flow, but the short circuit fries the power electrics in the buck converter (MOSFET/IGBTs can fail _short_). The charger will have contactors that physically disconnect the line from the converter, but they normally interrupt the line with zero voltage when the controlling IGBTs are closed.
In this case, they'll have to interrupt high voltage and high current flow. Can they do it reliably within the fractions of a second?
Require a coin-operated 120V outlet with gfci and accessible way to reset the breaker for every two parking spots, everywhere. Many benefits: 1. Everywhere you go, you know there'll be somewhere to charge overnight. 2. It's the cheapest per installed spot, by far, allowing way more locations. 3. Renters can safely by an electric car and have home charging. 4. Coin-op 120V are far more robust than cables with valuable…
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Like Henry Ford tried on the Model T: The Model T was offered in three fuels: Gasoline, Electric, and Alcohol. It only took I think less than a year to make it Gasoline only.
Is there any universe where we go the electric route instead of gasoline back then? I imagine the range was nothing
It would be nice if instead of the fast charging problem the focus would be shifted to standardized battery packs, that can be field replaced. I don't really want to own 50-100kwh battery. I just want to use the charge in it and happy to pay for that.
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> Lightning strikes...how do EVs currently guard against it? They don't. If lightning strikes, you make a claim and get an insurance payoff. > Without galvanic isolation, battery goes...boom? Hopefully without you or your family waiting inside the vehicle under some false pretense of safety. Nope. The lightning current won't go through the battery, it'll just melt the conductors in the charging cable.
> Nope. The lightning current won't go through the battery, it'll just melt the conductors in the charging cable. This strikes me as a direct consequence of galvanic isolation provided by isolation link stage in prevailing architectures, something the article proposes to eliminate. I'm struggling to imagine how a magnitude of surge energy sufficient to "melt the conductors in the charging cable" while directly couple…
For the battery to explode, the lightning will need to cause a potential difference across its terminals. But why would it? The paths _around_ the battery cells (through the battery and car body) have much less resistance.
The conductors in the charging cable can melt, because the path from the car, though the cable, and through the EVSE body to the ground is another relatively low-resistance path.
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The timeline is even longer (and with such good cause). It also took till March 2023 to specify federal requirements for a charger! That's not a bad thing, it's not unreasonable at all. We didn't have any open systems for charging until then! There were no federal standards for what to build or how to stay or fall out of compliance! Before you start paying people to build chargers, you have to have some direction for…
Ok, but taking two years to come up with a big document of standards while Tesla was able to just do all that by themselves and then build more chargers for less is kind of the issue. I appreciate that it's not easy, but the not-easiness is the problem.
Tesla also has been operating on chargers for years! They took their own sweet time we just don't think about the first years!
Tesla never built standards. They just made something that sort of worked for them. That sort of somewhat helped some specific consumers find chargers, albeit with not enough status available to know what to expect when you got there.
None of that is at all good enough for actual infrastructure the world needs to be able to depend on. "Works for my car" isn't how gasoline works, and it's not how ev charging is gonna ever succeed.
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> as it'll have to be able to break the fault if it happens Are you talking about the case where both of the ground wires fail while charging? If either is non-functional when charging starts, it disallows charging. If one fails during charging, charging disconnects.
Imagine a catastrophic fault: a dude in another car drives into your car, and a conductor in the car breaks off and energizes the car body. The current now goes through the car body into the ground, and also through the grounding wire back to the charger (EVSE). It's a phase-to-ground short. The charger tries to interrupt the flow, but the short circuit fries the power electrics in the buck converter (MOSFET/IGBTs ca…