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We're Charging Our Cars Wrong

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Re: We're Charging Our Cars Wrong

#81

Post by stahtops »

This doesn't solve fundamental problems with how America has built its charging infrastructure.

We never should have placed hardwired cables on the L2 or L3 chargers. The CCS plugs are broken about 50% of the time? It's a joke.

Rented an EV in Europe... the cable is in the trunk! You own it. Take it out, plug it into the charger, plug it into your car.

Having a bad day? Drive over the plug? Smash it with a hammer? Don't know how plugs work so you tried to kick it off your car? No problem, go buy yourself a new one. The charger still works for everyone else.

The charger HW can be agnostic. Car manufacturers can make up whatever crazy plug they want for their car, just provide the cable.

Tesla wants a 1" cable? No problem!

You want a 300' cable? Do it!

Re: We're Charging Our Cars Wrong

#82

Post by DevelopingElk »

dhosek wrote: post #38
Elixir6419 wrote: post #10

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.

I remember reading an article somewhere which explained why this was an impractical issue. I forget the details, but I think issues like weight, ending up with a battery pack that doesn’t hold its charge well, etc. were all big concerns. Weight seems like it would be a huge problem given that the battery is the largest component of the EV drive train and it’s usually kept along the floor of the EV for weight distribu…

The movement has been towards making batteries structurally integral to the vehicle to save weight in the frame.

Re: We're Charging Our Cars Wrong

#83

Post by nextaccountic »

L-four wrote: post #71
nradov wrote: post #53

Earlier quoted context omitted.

Impractical? Nio is already doing battery swaps at scale in China. https://hbr.org/2024/05/how-one-chinese-ev-company-made-batt...

Dictatorships don't care if things are practical.

Battery swapping isn't some top-down authoritarian decision made by the CCP and forced into the Chinese society.

Nio is just a company that's providing a much needed solution to this problem.

Re: We're Charging Our Cars Wrong

#84

Post by mjan22640 »

superjan wrote: post #42
Elixir6419 wrote: post #10

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.

A battery can weigh up to half a ton. Because of the weight, you want to keep it at a low position in the car. That is not easy to swap. By contrast consider that you charge your car. For a daily commute, the most practical is to charge it on your driveway or at the office. In my case that means I only have to consider public charging on vacations and longer weekend trips. Now this means my net travel speed is lower…

It is actually practical position for an automated swap. You drive to the position, the door on the ground open, the robot pulls the old battery and installs the new one, no hassle.

Re: We're Charging Our Cars Wrong

#85

Post by LooseMarmoset »

jdminhbg wrote: post #43
rexpop wrote: post #26

Earlier quoted context omitted.

The National Electric Vehicle Infrastructure (NEVI) Formula Program and the Charging and Fueling Infrastructure (CFI) Discretionary Grant Program have made significant progress in expanding electric vehicle (EV) charging infrastructure across the United States. As of July 2024, eight states had opened their first NEVI-funded stations, totaling 61 ports, and powered thousands of charging sessions. Over the course of t…

> Over the course of the Biden-Harris Administration, the number of publicly available EV chargers more than doubled. With approximately 1,000 new public chargers being added each week, there are over 200,000 publicly available charging ports. The trick being played here is counting all charging stations in the US and pretending they're part of the IRA's funding.

Yes, that is a neat trick.

> As of July 2024, eight states had opened their first NEVI-funded stations, totaling 61 ports, and powered thousands of charging sessions.

As of FY 2024, $2.385 billion had been allocated from the funding. For 61 ports across 4 (four) charging locations. $39M PER PORT.

This, per NEVI's own numbers: https://driveelectric.gov/files/nevi-annual-report-2023-2024...

I would sure like to see a breakdown in how that 2.3B was spent.

Re: We're Charging Our Cars Wrong

#86

Post by Vecr »

adgjlsfhk1 wrote: post #62
reaperman wrote: post #39

Earlier quoted context omitted.

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…

the big division we need to kill is ethanol in fuel. it's 30% less efficient than gas, much more expensive, produces more CO2 and gums up and destroys engines if you let it sit for a few weeks.

You need some. Otherwise you would need to re-engineer for a different anti-knock. Tetraethyllead is unusable in modern cars.

Re: We're Charging Our Cars Wrong

#87

Post by adrianN »

TechDebtDevin wrote: post #41
ForOldHack wrote: post #19

Earlier quoted context omitted.

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

When cars where new they didn't go very fast and ICE efficiency was very bad. It just turned out that it's a lot easier to improve ICE power output and tank size than to improve batteries.

Re: We're Charging Our Cars Wrong

#88

Post by coryrc »

stahtops wrote: post #65
coryrc wrote: post #17

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…

L1 charging isn't really appropriate anywhere except at home or something like an airport parking lot where cars may be plugged in for a significant amount of time.. like 24h+. It's very slow.

It's 7 mph of charging. The average car is driving 60 minutes per day, and if there are chargers everywhere that's 161 miles per day of charge if it's plugged in when not driven.

That covers everything the existing system doesn't already.

Re: We're Charging Our Cars Wrong

#89

Post by coryrc »

notpushkin wrote: post #49
coryrc wrote: post #17

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…

This. Maybe then upgrade to 240V and some standard-issue EVSEs. And no need to invent new ways to charge people – paid parking is a solved problem. Just set out a section for EVs (and EVs only).

EVSEs are more fragile, more prone to vandalism, so more costly to keep running.

240V could use the same wires and double available power, but existing portable chargers never draw more than 16A from 120V, so people can't screw it up.

Re: We're Charging Our Cars Wrong

#90

Post by DevelopingElk »

wtallis wrote: post #29
nickff wrote: post #14

Earlier quoted context omitted.

The system proposed in this piece could probably be safely implemented, but it would much more challenging to do than the author seems to indicate. There are a variety of failure modes that they ignore. The author also glosses over a 20% power loss (to heating), which would cost money and bulk to dissipate.

I particularly dislike how this article tries to sweep the power loss issue under the rug: The first mention of loss says that the isolation link is "responsible for about 50 percent of the charger’s power loss". The second mention of loss says "the power loss would be less than 20 percent". They want you to think that those numbers are comparable, and that they've reduced loss from 50% to 20%.

The article needs absolute efficiency figures to know if this is a good idea. I also wonder if better conversation electronics could make a difference. I'm guessing there is some tradeoff between cost of conversion and volume/weight/efficiency.

The other question is how this fits in with regenerative braking. Is this power conversion circuit dual purpose?

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