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Thanks for the videos Eric. The forklift situation is very similar to what we are trying to accomplish with BEVs. After looking at the battery swap-out station and the newer quick-charge stations I think it is more clear that quick charging is the way to go.

Notice how the culture for forklift driver is changed from going out of his way to go "fill up" his vehicle to plugging in whenever he stops for any reason (bathroom break, scheduled breaks, lunch, etc.). This is analogous to the plug-in hybrid or BEV situation where people will not have to go out of their way to a service station but simply plug in whenever they stop. Notice how the swap-out station was completely removed freeing up all that space? Hummmm. Opens my mind up to the possibilities for future quick-charge stations to have radically different designs.

Now there is one point I would like to keep stressing. Please look at the following forklift charger:

http://www.posicharge.com/ELT.pdf

If you look at the cord on this sucker you will be amazed at how big it is. Can housewives lug that around? That's not even the real kicker. The real kicker is that cord can ONLY deliver 36 kW of power. If you were to pull up to a station with your Tesla and plug in with that cord it would take 1.5 hours to charge! I'm thinking that the required quick-charge port will be an induction coupled 225 kW (or even more eventually) monster. Sure you could drive up and plug 7 of the above mentioned cords into your Tesla but... Thus, I'm convinced that the charging must be a fully automated experience where an arm or some device moves in and attaches to the car (I'm thinking from under the car), delivers the charge and then comes back to home position.

One of the things I'm concerned about is the heat. Is the heat a problem? Will the vehicle have to liquid cool the battery during charging? Will the automated quick-charge port also be liquid cooled to help out the car? Will the quick-charge port have to be physically connected so that conductive cooling can be utilized? Those are all valid questions that I don't have answers to. I do however feel that even the worse case scenario can be handled safely and elegantly.
 

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In terms of quick charging, nothing is going to beat a capacitor, because capacitors are moving electrons instantaneously instead of physically moving ions.

I don't know whether there will be a meaningful quick-charge infrastructure in my lifetime. But as far as I can tell, the capacitor is the only technology that can charge faster than your typical gas pump.
I don't disagree with what you are saying at all. Capacitors are and will always be much more capable of quick charging than batteries. I just don't believe that benefit is important to personal automobile since batteries are capable enough. With home charging, work charging, etc.; quick charging will be relegated to long travels. I don't see much added value in 1 minute charging versus 15-20 minutes when it is rarely needed by most drivers. If quick charging does become a relevent technology, then the capacitor's charging advantage may be meaningful to the trucking and other large vehicle market. This, of course, is assuming a highly energy dense capacitor becomes a reality and the quick charging issues get resolved. The physics arguments are compelling against the feasibility of capacitors with energy densities claimed by EESTOR, but hopefully they've found a way around those theoretical limitations.
 

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One of the things I'm concerned about is the heat. Is the heat a problem? Will the vehicle have to liquid cool the battery during charging? Will the automated quick-charge port also be liquid cooled to help out the car? Will the quick-charge port have to be physically connected so that conductive cooling can be utilized? Those are all valid questions that I don't have answers to. I do however feel that even the worse case scenario can be handled safely and elegantly.
Heat would absolutely be an issue. As I'm sure you are aware, all energy not making into the battery as stored electrochemical energy will become heat. The more efficient the charger, the cables, the cars charging circuitry, and the battery the less the heat. There isn't any more heat generated with fast charging than with slow charging if the efficiencies are the same, but generally the efficiencies are lower. The issue isn't the total amount of heat but rather the compressed in which is generated. Certainly this is not insurmounted on the charger side, but will prove diffcult on the car side.

The biggest concerns I have about fast charging are not technical, but rather they are business concerns. In order for fast charging to be of much value, the battery must be fully capable of a reasonable range (>200 miles in my opinion). This means there won't be much a market for it until batteries come down roughly 3-fold in cost/KWh. Another 2 fold improvement past that and the market starts declining.

Even when batteries are $12K for 50KWh, I don't think most people will opt for a full 50KWh battery even if quick charging is available. They could buy a 100 mile AER E-REV for a couple thousand less and have better range plus more redundancy. Personally, once the range is 120 miles I would opt for a BEV and save the $6K or so. The 3-4 trips per year that I need more range I will drive our E-REV. If I were in a single car household, I would probable still buy a BEV and rent an E-REV for those few trips. When batteries get to $12K for 100KWh, I'll still probably on buy $6K worth and rent the rest or rent a 100KWh BEV and never need quick charging.

I'm not saying quick charging won't ever work under any circumstances, rather it would be a nice benefit and satisfy some real need but that need is limited in the personal automobile market. I do think it would have much greater value to the trucking market and perhaps this need will be enough to create viable business argument.

The technology and battery development (price and capacity) will be available for battery renting and swapping long before quick charging and there will be a viable business case for it for a much longer period of time.
 

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That charger puts out 600amps at only 60 volts DC for a total of 36kw. Thats why the cord has to be so big and the output so little.

A 240vac 600amp version would charge at 144,000watts or 144kw with the same size wire gauge. A 600vac 600amp version would charge at 336kw, still same gauge wire. Get it?

But just like a 100 mile 1000lb battery for the Volt isn't ideal to fit the design requirements, 336kw charging cable is definitely too big and therefore also not ideal.

The cable I'm looking at is about the same size as a gasoline pump hose, almost as flexible, and about twice the weight. Easily handled by anyone. It can carry about 130kw. I picture them partially retractable and hanging within arms reach when not in use. (we can't have them dragging on the ground like gas hoses) We've got to stay away from expensive, high maintenance robotics. Keep it simple and cost effective. Aerovironment has already figured it out, they are the company who developed the quick charger for the BEV in the video I posted earlier in this thread. That was a 14kwh charge in ten minutes.
 

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I think I need to re-post this for those of you who may not have seen it. This is a video of an all electric car getting a 14kwh charge in ten minutes.

Notice the charge is:
-Not next to a powerline substation
-Charger is in a very small portable trailer
-Charging cable is a manageable size and weight
-The batteries in the car don't need a fancy cooling system

Considering this is experimental, it seems to be relatively simple compared to the battery technology.

If you've already seen this its still worth a second look:
Video 1- http://youtube.com/watch?v=TrzEt1uBRJ8&feature=related

Video 2- http://youtube.com/watch?v=Rcbx57Azisw&feature=related
 

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A 240vac 600amp version would charge at 144,000watts or 144kw with the same size wire gauge. A 600vac 600amp version would charge at 336kw, still same gauge wire. Get it?
lol. Yeah, I get it my friend. However, It's unlikely that DOT is going to approve a 600 VAC line that is going to be handled by grandmothers! ;)


Koz, I do agree with you on the hybrid solution... For the short-term. To me having two complete systems in one vehicle is, well, transitional. I realize that what I'm talking about will probably not be viable for at least 5 years down the road. I'm betting on nanotechnology to bring us a high capacity, quick charge electrical storage solution (Heck, there are even companies demonstrating quick-charge lithium-ion today - I don't think I'm stretching things too much). I'm also betting that there are many people and families out there who will have, or will only be able to afford (cost of energy is going up and that means everything will go up) one car in the future. I'm betting that they would enjoy the freedom of jumping on the interstate roads and traveling to other cities (international travel is sure to become a much more expensive luxury) and to be able to stop at the rest station every few hours of driving to stretch their legs, hit the bathroom, and quick-charge their ride. To me it seems like a pure, simple, efficient, environmentally clean solution that does not require a drop of hydrocarbon burning. Pure solar-to-storage-to-wheel. Perfect... You could make a GM hywire-like electrified sled and swap out the battery and put on a new fresh and stylish body every 200,000 miles or so. The life of these platforms will be unheard of.
 

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Eric, Great links! Did you check out that power plug? Also, 600 VDC is a lot of voltage. I would like to hear what DOT thinks. What would they accept, etc.

It's what I expected however - huge! I'm still leaning toward the automated system. Why?

1) Can handle 225 kW or more and granny doesn't need to touch it.

2) Can include cooling hoses and such if needed.

3) Safer.

4) It's not as complicated as you think to automate. The cycles times are extremely low by automation standards. Automation has come a long way baby.
 

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lol. Yeah, I get it my friend. However, It's unlikely that DOT is going to approve a 600 VAC line that is going to be handled by grandmothers! ;)
There should be a way to design the plug so that it can tell whether it is plugged in correctly before applying power. It might have 4 conductors - two power and two signal. The signal conductors would not make contact until the connection was sealed. As a backup, the charger would also have a very sensitive GFI.

I seem to remember that California installed 480VAC public charging stations. If there was no regulatory problem there, then why a problem for 600VAC? Once you're above some lethal threshold, does it matter how far above you are? Granny could spray gasoline all over the gas station and then drop a butt, but she doesn't, right?

If the EESTOR capacitors charge up to 3000V, then it seems like (up to) 3000V DC charging makes sense. And I think that DC current requirements might be exactly why EESTOR chose such a high voltage.
 

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Are you sure the 480 VAC was on the plug-in side? For example, It's common for companies to have equipment that is fed by 480 VAC 3-phase but the operators are not allowed anywhere near that. The parts of the machine that they are allowed to work with are usually limited to standard 110 VAC single phase voltages. I would not allow an untrained person to plug in a high-voltage welder for example. I would really like to see what DOT has to say on the matter. I hope you are right because it would make things much easier. What they have to say will determine the design path.
 

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Are you sure the 480 VAC was on the plug-in side? For example, It's common for companies to have equipment that is fed by 480 VAC 3-phase but the operators are not allowed anywhere near that. The parts of the machine that they are allowed to work with are usually limited to standard 110 VAC single phase voltages. I would not allow an untrained person to plug in a high-voltage welder for example. I would really like to see what DOT has to say on the matter. I hope you are right because it would make things much easier. What they have to say will determine the design path.
You're probably right on this. If anyone cares, some relevant standards are:

NFPA (NEC Article 625)
SAE (J1772, J1773, J2293, etc...)
UL (2202, 2231, 2251, etc...)
FCC (Title 47 - Part 15)
 

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I been thinking about what people says about quick charge point of view. I think some people just got too far ahead of the game here. In my view, the "quick charge" is some form of the engine that in E-REV.
I'm more dislike about the battery swaping. There is no standard of how to unload and load the battery. Some people think it just drop and load. It could be just as bad to load and unload a engine or transmisstion. If you look at the you tube video of how the battery been replace in the Prius plug-in conversion. Imagine, the worker is going to trash up inside the cars.

http://youtube.com/watch?v=icRjfaeoQnE

So just stick with the E-REV, untill battery energy compacts grow as time goes by. It will get to the point that it does not matter how long it take to charge the battery fully where people barely able to fully drain the battery low.
 
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