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Problem with on-board rectifier is that you need 1 for every vehicle (and it's lugged around most of the time). It's a waste of money.

On-board rectifiers also do not allow V2G, so we will need to install those separately anyway. Again, waste of money.

But agree that it's entrenched when EV adoption was very low. Hopefully it gets dropped as EV adoption grows and car makers realize this.
 

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Actually, I'm on the lookout for L2 chargers all over the place because I can leave the car charging at them while I go and do something without having to worry about getting back to the car when the charge finishes. There are plenty of times where I want to get some charge but I don't necessarily need to fill the car completely and I don't want to have to worry about the car sitting in an EV stall and not charging.
There's a solution for this problem too: multi-headed chargers that serve multiple parking spaces. A single medium speed DCFC charger that serves 4 parking spaces for example can provide both a decent charge when required or can more slowly service multiple EVs. Have a kiosk where a driver can inform the station of the amount of power they need and the amount of time the station has to deliver it and the station can schedule the charge so that each car connecting gets what it needs in the timeframes that are available for each EV.

L2 doesn't work because it's always slow, which makes it inflexible. When it comes to public charging, in addition to more access, we really need more flexible options that aren't going to break the bank.

ga2500ev
 

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Problem with on-board rectifier is that you need 1 for every vehicle (and it's lugged around most of the time). It's a waste of money.

On-board rectifiers also do not allow V2G, so we will need to install those separately anyway. Again, waste of money.

But agree that it's entrenched when EV adoption was very low. Hopefully it gets dropped as EV adoption grows and car makers realize this.
Sean's right about the high costs of DC chargers. And, there's a TON of L2 J1772 infrastructure out there. And, in Europe, there's a ton of AC (Mennekes Type 2) charging infrastructure out there. Both of these use the car's on-board charger.

This doesn't include the AC (J1772, Tesla, Mennekes Type 2, etc.) charging infrastructure installed at home and the many Destination Charging | Tesla (are Tesla wall connectors which are J1772 behind the scenes) out there.

To make an EV that doesn't work with any of the above seems like it'd be suicide.

Perhaps you guys who keep pushing for the OBC to go away should look at Wayback Machine and the reasons for the EVSE acting as a smart safety switch: Basics of SAE J1772.
 

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L2 doesn't work because it's always slow, which makes it inflexible. When it comes to public charging, in addition to more access, we really need more flexible options that aren't going to break the bank.
When it comes to public charging, AC "chargers" are the more flexible options that don't break the bank. Nobody is preventing businesses from installing DC chargers other than the cost of them. So we use L2 for slow charging, or DC for fast charging. That's flexible, isn't it? The only difference in a DC-only world is that it would cost businesses more to provide slow charging. Yeah, they could provide AC outlets but frankly I prefer using their EVSEs rather than having my own pricey DC charger sitting around in a public place where it might be vandalized or stolen.

It seems to me that the only thing you're really railing against is having the charger built into the car. And I agree that it would have been nice to have been able to avoid that. But that's not where we are, and I don't see why the situation we have is all that terrible other than the very small difference in price between having the on-board charger vs. having the dealer supply a low power offboard DC charger.
 

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In low EV penetration scenario, having built in rectifier is cheaper. Imagine 1 EV that would use various AC EVSE around town.

In high EV penetration scenario, having external rectifier is cheaper. Imagine one garage with 2 cars but only 1 DC charger instead of 2 built-in recrifier. Or, one EV with portable receifier charging at many different locations (same as first case).
 

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In high EV penetration scenario, having external rectifier is cheaper. Imagine one garage with 2 cars but only 1 DC charger instead of 2 built-in recrifier.
Wouldn't most people with 2 electric cars would choose to have two chargers? It seems to me like only ever being able to charge one at a time would be problematic. I suppose some folks might be OK with a "dual head" charger that could alternate between vehicles, but if it were me I'd like to be able to charge both at once.
 

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Wouldn't most people with 2 electric cars would choose to have two chargers? It seems to me like only ever being able to charge one at a time would be problematic. I suppose some folks might be OK with a "dual head" charger that could alternate between vehicles, but if it were me I'd like to be able to charge both at once.
Yeah, the home charger would likely have 2 heads and share power. When only 1 EV is charging, you would charge at double the speed.

Another benefit to have the rectifier external is that it would not be part of the vehicle, thus not part of the 8 or 10 year warranty (Our OEM EVSE is probably only warranted for a couple of years). ;)
 

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When it comes to public charging, AC "chargers" are the more flexible options that don't break the bank.
They are not more flexible. Onboard chargers are designed for a specific inflexible purpose: to fully recharge the EV in a 4-10 hour timeframe. No matter how much power is actually available, and no matter how much time the driver actually has available, no L2 is ever going to charge faster than that.

Is it cheap? Sure. But L2 in the public space rarely is effective in giving a significant charge to an EV without having to invest a significant amount of time to do so.
Nobody is preventing businesses from installing DC chargers other than the cost of them. So we use L2 for slow charging, or DC for fast charging. That's flexible, isn't it? The only difference in a DC-only world is that it would cost businesses more to provide slow charging.
I think there are multiple levels of reason of why it doesn't happen. Cost is a part of the equation. But I think even more is a lack of understanding of the effectiveness of L2 and the pervasive idea that all DCFC options are exhorbitantly expensive because everyone thinks that DCFC is 50 kW and up requiring tens of thousands of dollars and upgraded electrical infrastructure to install. In short folks install L2 only simply because they don't know any better.
Yeah, they could provide AC outlets but frankly I prefer using their EVSEs rather than having my own pricey DC charger sitting around in a public place where it might be vandalized or stolen.

It seems to me that the only thing you're really railing against is having the charger built into the car.
Actually I'm railing against limited public charging options due to EV group think. Pulling onboard chargers from EVs would finally free them from being limited to either only charging at speeds limited by those onboard chargers. It's a crutch that propogates the idea that putting in L2 is good enough. It isn't.
And I agree that it would have been nice to have been able to avoid that. But that's not where we are, and I don't see why the situation we have is all that terrible other than the very small difference in price between having the on-board charger vs. having the dealer supply a low power offboard DC charger.
When all charging is DCFC, then virtually all charging will match the power of the input, and not be limited to the charging limit of the onboard charger. The flexibility will be unlimited. As I said in my previous post this can be done with the onboard charger in place. But as long as L2 is an option for shared public charging, far too many places who should offer better faster charging options will fail to do so.

ga2500ev
 

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I can see manufacturers dropping the built-in rectifier in a decade, as EVs become more common and they try to cut cost to compete on price.
 

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Wouldn't most people with 2 electric cars would choose to have two chargers? It seems to me like only ever being able to charge one at a time would be problematic. I suppose some folks might be OK with a "dual head" charger that could alternate between vehicles, but if it were me I'd like to be able to charge both at once.
I use my current driveway as an example: 5 adult drivers with 6 vehicles. Would 4-6 chargers in that situation presuming all of the vehicles were EVs really be the best option? Or would the option of having a faster charger, say 20 kW, coupled with multiple 200+ mile range vehicles better serve the refueling needs of the fleet? Or would a combination of both be appropriate?

These are interesting questions to ask as we move forward.

ga2500ev
 

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Yeah, the home charger would likely have 2 heads and share power. When only 1 EV is charging, you would charge at double the speed.
You can't have a multi-head DC charger that charges two EVs simultaneously because each EV may be requesting a different DC voltage based on the state of charge of its battery. A multi-head DC charger could charge one car, and then automatically switch to another - but not both at the same time.

They are not more flexible. Onboard chargers are designed for a specific inflexible purpose: to fully recharge the EV in a 4-10 hour timeframe.
I'm not saying the charger itself is flexible, I'm saying that we have just as much flexibility in terms of charging opportunities available to us. You go to an L2 charger (or low-power DC charger) for a partial top-up or overnight charge, or you go to a high power DC charger for a fast charge. There's nothing about having a limited AC charger built into the car that limits what you can today do in terms of charging. You want faster charging than is capable with the built-in charger? Go to a faster DC charger. That's what you'd have to do anyway if you didn't have the built-in charger and only had the low-capacity DC charger supplied with the car. The current situation with built-in chargers doesn't give us any less flexibility in terms of what we can do, and I believe that it gives us more low-power charging opportunities at businesses because it's cheaper for them to install L2 chargers.

You can claim that the built-in charger is expensive and in some cases redundant, but you can't say it limits our options.

...as long as L2 is an option for shared public charging, far too many places who should offer better faster charging options will fail to do so.
You and I disagree on this. I believe that if DC charging was ubiquitous, fewer businesses would offer charging (or offer fewer charging stations) because it would be more expensive to install. And because DC chargers of higher capacity cost more to purchase and install than those of lower capacity (unlike L2 chargers, which actually range up to 80A), I'm very skeptical that the types of businesses at which you see L2 charging today would pay more to install mid- to high-capacity DC chargers. So I just don't see any substantial benefit to a world in which all charging is done via DC chargers.

Perhaps the truth lies somewhere in the middle. But we're unlikely to ever know for sure, because the current system is entrenched and I see no signs that it will change.
 

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You can't have a multi-head DC charger that charges two EVs simultaneously because each EV may be requesting a different DC voltage based on the state of charge of its battery. A multi-head DC charger could charge one car, and then automatically switch to another - but not both at the same time.
That is correct. But presuming that the DCFC offers higher power than the individual onboard chargers, serially charging would generally not be an issue. For example a 20 kW home DCFC could fully charge a car in 1/3 the time of the onboard charger.

I'm not saying the charger itself is flexible, I'm saying that we have just as much flexibility in terms of charging opportunities available to us. You go to an L2 charger (or low-power DC charger) for a partial top-up or overnight charge, or you go to a high power DC charger for a fast charge. There's nothing about having a limited AC charger built into the car that limits what you can today do in terms of charging. You want faster charging than is capable with the built-in charger? Go to a faster DC charger.
But that's the problem. The only faster DC chargers are the ultra fast travel chargers because the entire industry thinks that the only purpose of DCFC is ultra fast travel charging. So there are minimum options between slow L2 and ultra fast travel DCFC. And as you have pointed out, since ultra fast DCFC is so expensive to install and operate, they are fewer and farther between.

Let me motivate with an example. I happen to live near a pair of Volta free L2 charger installed at a local grocery store, about 5 miles from the house. It's a convenient opportunity because it's possible to grab a bit of a charge when stopping at the grocery to grab some items. But honestly it's decoration as using it when stopped at the grocery gives a minimal charge, while using it to do a functional recharge takes so much time that it isn't worth the effort. BTW the nearest DCFC happens to be 10 miles away.

I'm aware that Volta has started a pilot to start intalling DCFC. But the point is that while the L2 offers access, it doesn't offer utility because of the limitations on the speeds that it can charge. A 25-50 kW DCFC in the same spot would offer a much more useful range of charges in the timeframes people tend to spend in grocery store strip mall situations. The power matches the utility, not simply having the access.
That's what you'd have to do anyway if you didn't have the built-in charger and only had the low-capacity DC charger supplied with the car. The current situation with built-in chargers doesn't give us any less flexibility in terms of what we can do, and I believe that it gives us more low-power charging opportunities at businesses because it's cheaper for them to install L2 chargers.
You can claim that the built-in charger is expensive and in some cases redundant, but you can't say it limits our options.
They do because folks installing chargers use them as a crutch. If L2 wasn't an option for installation in the public charging space, then at least a percentage of the folks who install L2 would upgrade to faster DCFC. But with no real pressure to do so, very few do. Only Harley has made a committed investment in installing 25 kW DCFC in their dealerships. And reading reports here, while clearly not as fast as ultra fast travel chargers, they offer decent charges to those who use them in some useful timeframes.

You and I disagree on this. I believe that if DC charging was ubiquitous, fewer businesses would offer charging (or offer fewer charging stations) because it would be more expensive to install. And because DC chargers of higher capacity cost more to purchase and install than those of lower capacity (unlike L2 chargers, which actually range up to 80A), I'm very skeptical that the types of businesses at which you see L2 charging today would pay more to install mid- to high-capacity DC chargers. So I just don't see any substantial benefit to a world in which all charging is done via DC chargers.
It being more expensive to install is a bit of a fallacy. Commercial L2 like chargepoint dual heads are not cheap. They tend to run in the $6000 range. They require 15 kW of commercial power to run. 25 kW DCFC can be purchased off the shelf in price ranges from $7500 to $12k. While a bit more pricey those prices are not orders of magnitude difference. And they can be powered using the same electrical infrastructure that chargepoint and Eaton style L2 stations are powered with.
Perhaps the truth lies somewhere in the middle. But we're unlikely to ever know for sure, because the current system is entrenched and I see no signs that it will change.
As I'm sure you've figured out, I really don't care about the onboard charger one way or the other. But as EVs move from early adopters like us, to the early majority like our family and friends, it's going to be critical to start deploying a public charging infrastructure that is usable without forcing folks to drive out of their way to effectively use. People are not going to be willing to sit around and wait for L2 to charge. And unlike us, there is going to be a percentage of folks who will not have effective home/work charging opportunities. They will need to charge when they are parked in other public places while doing other public activities. And promoting the belief that L2 is going to be good enough to support this is going to be an epic fail.

ga2500ev
 

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Actually, I'm on the lookout for L2 chargers all over the place because I can leave the car charging at them while I go and do something without having to worry about getting back to the car when the charge finishes. There are plenty of times where I want to get some charge but I don't necessarily need to fill the car completely and I don't want to have to worry about the car sitting in an EV stall and not charging.
I'm actually planning on putting a request to Cornell Transportation Services that they augment their dual-port L2 in the Hoy Road garage with NEMA 6-20 outlets (or even even 5-15 would be good just for reducing the penalty of preconditioning.)

There are only 2 L2 ports, with a time limit of three hours. A typical hockey game across the street at Lynah Rink is around 3 hours if it doesn't hit OT, longer than 3 if the game goes into OT.

So I can't plug in to the L2 ports unless I leave the game early or arrive late. But just a little juice to battle winter range penalties would be a wonderful thing and require far less investment on Cornell's part.

Note that the spaces in question are ALREADY reserved for alternative fuel vehicles - there are 10-15 reserved spots, but only a ChargePoint bollard serving two of them.
 
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