Quick Charging

The "perception" is that an EV can travel anywhere with quick charging along the way. This may not be the case. The LEAF manual recommends quick charging no more than once a day. The dealer on p/u day made sure to tell me the same thing.

So, what is the purpose of the network of quick chargers WA, OR, and CA are putting in along the I-5 corridor? A possible waste of fed tax money?

I made my purchase decision on other major factors so it won't bother me too much-more of an inconvenience than anything else.

saywatt said:

The "perception" is that an EV can travel anywhere with quick charging along the way. This may not be the case. The LEAF manual recommends quick charging no more than once a day. The dealer on p/u day made sure to tell me the same thing.

So, what is the purpose of the network of quick chargers WA, OR, and CA are putting in along the I-5 corridor? A possible waste of fed tax money?

I made my purchase decision on other major factors so it won't bother me too much-more of an inconvenience than anything else.

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I probably wouldn't QC my car more than once on any given day. Maybe twice at a pinch. And having just used a quick charger, I definitely don't feel they're a waste of money. I do, however, think they're overpriced.

Even if you could quick charge an infinite number of times a day, would you really drive a long trip having to stop EVERY HOUR for 30 minutes to charge? And what if there is a long line at the charger or junkies stole the copper wire and disabled it or.... QC Ports on the highway don't make any sense to me until the range of EVs goes to at least 300 miles.. so that we wouldn't have to stop any more often then an ICE car stops for gas. Fortunately there ventually will be EVs with this range so the infrastructure cost is not wasted, just premature.

Agreed. Even a real, honest, freeway range of 150 miles would work.

Four charges just to get to Vegas, for example, is simply unrealistic. One midway would be just fine.

SteveInSeattle said:

Even if you could quick charge an infinite number of times a day, would you really drive a long trip having to stop EVERY HOUR for 30 minutes to charge? And what if there is a long line at the charger or junkies stole the copper wire and disabled it or.... QC Ports on the highway don't make any sense to me until the range of EVs goes to at least 300 miles.. so that we wouldn't have to stop any more often then an ICE car stops for gas. Fortunately there ventually will be EVs with this range so the infrastructure cost is not wasted, just premature.

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SteveInSeattle said:

...QC Ports on the highway don't make any sense to me until the range of EVs goes to at least 300 miles.. so that we wouldn't have to stop any more often then an ICE car stops for gas. Fortunately there ventually will be EVs with this range so the infrastructure cost is not wasted, just premature.

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I wouldn't drive more than one or two QCs away. I WOULD use it to do day trips for shopping or sightseeing in Orange County or LA. Drive up, QC once over coffee or shopping, drive around town doing whatever else I needed, QC again for the drive home. Sure, in a perfect world, there'd be L2 at all of my stops, and QC might not be needed, but the world isn't perfect...besides the point of all this is to build infrastructure for the future. The chicken and egg problem only gets solved by building both chickens and eggs at whatever rate we can manage. If you refuse to build because it's "premature" you never get there.

saywatt said:

The "perception" is that an EV can travel anywhere with quick charging along the way. This may not be the case. The LEAF manual recommends quick charging no more than once a day. The dealer on p/u day made sure to tell me the same thing.

So, what is the purpose of the network of quick chargers WA, OR, and CA are putting in along the I-5 corridor? A possible waste of fed tax money?

I made my purchase decision on other major factors so it won't bother me too much-more of an inconvenience than anything else.

Click to expand...

Nissan just doesn't want you to DC Quick Charge multiple times a day, everyday.

Every time a battery is used, the chemistry changes just a little bit, causing degradation. Nissan's statement is to try to minimize cycles on the battery pack. If you wanted to take a trip for the weekend and quick charge 5 or 6 times once or twice a year, it wouldn't affect the battery over the long-term.

I would think the reason they are putting the charging stations so close together is for the same reason there are so many gas stations along the freeway, because people with different vehicles and starting points need fill ups at different intervals. The network isn't being built for the LEAF, but for a future array of EV vehicles with likely a much longer range. It's my understanding that even the Leaf can handle the occasional abuse of multiple fast charges in a day, it's really what you do every day that adds up. As soon as the range doubles, with cars like the Tesla S coming soon with a 300 mile range, stopping to charge for a half an hour every 4-5 hours will not be such a big deal and the wisdom of frequent stations to charge will become very apparent, IMHO.
g

GaslessInSeattle said:

cars like the Tesla S coming soon with a 300 mile range, stopping to charge for a half an hour every 4-5 hours will not be such a big deal and the wisdom of frequent stations to charge will become very apparent, IMHO.
g

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I'm no physicist or EE but I think it's a pretty big stretch to assume that quick charging for 300 miles of range would still only take 30 minutes. Improvements in the energy density of batteries don't necessarily imply equally impressive improvements in charging speed, in fact I would not be surprised if the opposite turned out to be true (eg higher temps in the smaller/denser packaging) - you're still talking about transferring the same "amount of electricity" per mile of range - the laws of physics the motor and mass/shape of the car have to respect relative to gravity, friction and air resistance aren't going to change.

I forgot to look at the battery temperature gauge yesterday as I did the QC.

As soon as I can QC from a lower point, and Log the CAN busses,
I should be able to find the battery temperature value(s), and temp-bars.

Yes good point, and still, as capacity increases, the convenience factor is bound to improve many fold due to far fewer stops. Even if larger capacity vehicles take longer than a half an hour to charge, a QC network will be very freeing. In reality though, the largest effect of the QC network may end up being psychological. As soon as you can answer the question of "how far can you go?" with "as far as you want!", the number one psycological hurdle for the public will have been surmounted.

From what i'm seeing with nearly 3,500 miles on the LEAF in just a few months, most of the challenge with this technology spreading is between the ears of the prospective driver.

g

wsbca said:

GaslessInSeattle said:

cars like the Tesla S coming soon with a 300 mile range, stopping to charge for a half an hour every 4-5 hours will not be such a big deal and the wisdom of frequent stations to charge will become very apparent, IMHO.
g

Click to expand...

I'm no physicist or EE but I think it's a pretty big stretch to assume that quick charging for 300 miles of range would still only take 30 minutes. Improvements in the energy density of batteries don't necessarily imply equally impressive improvements in charging speed, in fact I would not be surprised if the opposite turned out to be true (eg higher temps in the smaller/denser packaging) - you're still talking about transferring the same "amount of electricity" per mile of range - the laws of physics the motor and mass/shape of the car have to respect relative to gravity, friction and air resistance aren't going to change.

Click to expand...

GaslessInSeattle said:

I'm no physicist or EE but I think it's a pretty big stretch to assume that quick charging for 300 miles of range would still only take 30 minutes.

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I doubt anyone is realistically expecting that. I would imagine you'd be looking at something like 2.5-3 hours. But then, honestly, after 250-300 miles I'm ready to stop for at least a couple of hours and eat/rest. Actually, I don't like to drive more than 300 miles, period, so I'm probably good for L2 charging overnight (assuming 6.6kW or better on the charger).

wsbca said:

GaslessInSeattle said:

cars like the Tesla S coming soon with a 300 mile range, stopping to charge for a half an hour every 4-5 hours will not be such a big deal and the wisdom of frequent stations to charge will become very apparent, IMHO.

Click to expand...

I'm no physicist or EE but I think it's a pretty big stretch to assume that quick charging for 300 miles of range would still only take 30 minutes. Improvements in the energy density of batteries don't necessarily imply equally impressive improvements in charging speed, in fact I would not be surprised if the opposite turned out to be true (eg higher temps in the smaller/denser packaging) - you're still talking about transferring the same "amount of electricity" per mile of range - the laws of physics the motor and mass/shape of the car have to respect relative to gravity, friction and air resistance aren't going to change.

Click to expand...

Let's say the Tesla S was using LEAF batteries - but had 3x the batteries - 72 kWh instead of 24 kWh.

There's nothing there that would keep the bigger pack from taking a 1.6C charge - charging from empty to 80% in 30 minutes. A 1.6C charge rate is absolutely minimal in the battery world.

Of course - supply the battery with 150 kW instead of 50 kW is a big difference - you're going to need a lot of copper to push 150 kW for 30 minutes. Let's assume that the battery pack voltage stays around 500V - you need wire big enough to handle 300A - serious stuff. With bigger packs we'll likely start seeing battery pack voltages approach 1kV to avoid having to use such large diameter wire.