[KiwiEV]

From the NYT:

Shai Agassi stood in a warehouse on the outskirts of Tel Aviv one afternoon last month and watched his battery-swapping robot go to work. He was conducting a demonstration of the curious machine that is central to his two-year-old clean-energy company, which is called Better Place. Agassi’s grand plan is to kick-start the global adoption of electric cars by minimizing one of the biggest frustrations with the technology: the need for slow and frequent recharges. The robot is the key to his solution. Unlike most electric-car technologies, which generally require you to plug your car into a power source and recharge an onboard battery for hours, the Better Place robot is designed to reach under the chassis of an electric car, pluck its battery out and replace it with a new one, much the same way you’d put new batteries in a child’s toy.

http://www.nytimes.com/2009/04/19/magazine/19car-t.html?_r=1&pagewanted=all

I don't want to be a nay-sayer but I expect fast recharge technology will make this battery swapping idea a flash in the pan. I've heard of two seperate companies on the EVcast who've now sucessfully tested fast recharges in seconds. There's A123 and another one whos name escapes me (no, it's not Eestor). Give it 5 years - we're halfway there already.

I'm not a big fan of swapping batteries out but that's just a personal thing. I've also heard Project Better Place's cars won't let you recharge without an approved (metered) charging point so you can be "charged" in both senses.
It's not much fun if you have solar or need a top-up from a mates place.
I consider myself an optimist, but I'll use my famous "Sucessometer" for the predicted success of Project Better Place...

Configuring it now...

Plugging it in...

Hmmm. Only 13% chance of success. We'll have to wait and see for the real results!

 

[major]

I don't want to be a nay-sayer but I expect fast recharge technology will make this battery swapping idea a flash in the pan. I've heard of two seperate companies on the EVcast who've now sucessfully tested fast recharges in seconds.

Hey Kiwi,

Let's see. Recharge in seconds. Say 60 seconds, otherwise you'd have said minutes, right? O.K. Let's say a 30 kWhr battery. Unless my math sucks, you'd need a 1.8 megawatt charger to do 30 kWhr in 60 seconds. Your mate got an outlet for that?

Regards,

major

 

[rbgrn]

I'm all for the quick-charge option but according to some basic math I've heard, it would require a pair of copper cable 2" in diameter at 480v to be able to accomplish the task in 5 minutes. I can't imagine what it would be in under 1!

It is a battle of physics but as always, there are solutions. 1.8 Megawatts can be done and we can run 50kv into a car charging port to reduce cable diameter but safety will be a huge issue when we're talking about numbers that big.

I used to play with old neon sign transformers that ran at 10kv. It could arc for a solid inch or more and you could feel the electricity moving through you even when you're holding on to well insulated wires. This was at a few milliamps so no problem, but if a human were to hold on to a cable that had the capacity to push thousands of amps and it arced through them? Instant death I'd think.

 

[jlsawell]

I may be biased because I'm campaigning for a job at Better Place, but here goes:

Most people will only need to swap batteries once or twice a year. The existing pack will be more than enough for your commuter triangle: home/shops/work. Since 80% of city driving is commuting, plugging in at work/train station and home resolves a lot of the pollution/depletion issues.

And as for paying for recharge: you can't have it both ways. Imagine how good life would be if Tesla had allowed JP Morgan to charge for his wireless electricity? Imagine if all electrical appliances could draw current out of the air like a mobile phone signal? You'd only need a battery if you were going beyond the limits of the e-cloud.

I recognise that there are challenges, but these challenges pale into insignificance beside the alternatives: Hydrogen (26% efficient and you're sitting on a Hindenburg-style bomb) or biofuels (starve 50% of the population so the rich can drive to work).

Shai may have a few ideas that some of us see as crackpot, but let's have a look at some other people with so-called "crackpot" ideas:

The Wright Brothers
Einstein
Tesla
Edison
Morse
Ford
Sikorsky
Da Vinci
Copernicus
Newton
Darwin

Overall, their contribution was generally positive. Since the oil supply has either peaked or will in the next few years, Shai currently has the most funding/approval/govt influence going for him, compared to the rest of us.

And even if the battery swaps go the way of H2 filling stations due to some flash-charging technology, so long as the recharge grid allows V2G, it will take the strain off the oil and electricity networks and help cushion the effects of the last oil shock.

 

[KiwiEV]

Hey Kiwi,

Let's see. Recharge in seconds. Say 60 seconds, otherwise you'd have said minutes, right? O.K. Let's say a 30 kWhr battery. Unless my math sucks, you'd need a 1.8 megawatt charger to do 30 kWhr in 60 seconds. Your mate got an outlet for that?

Regards,

major

Don't be ridiculous, of course no house has an outlet to charge a 30 kW/h battery pack in 60 seconds.
In any case I consider a fast charge for that size pack to be around 20 minutes. I also see fast charging "stations" as a very likely possibility. More likely than all the world's car makers modifying car designs to take one kind of swappable battery. Check out the Venturi Fetish for an example of early (4 years ago) fast charging.

Tell you what Major, why don't we just let the future decide? Meet back here in 2029 ok?

 

[david85]

Huh, I didn't know Agassi was Israeli. Maybe thats part of the reason why he was able to get the idea going there first. Does anyone know of a video of this "hot swap" station in action? The use of bombing ordnance release mechanisms does sound like a decent solution to securing the battery.

One elephant in the room that no one seems to be mentioning is the problem of making a single battery pack in one location of the car. This worked for the tesla roadster because it is a two seater that borrows a lot of design philosophy from mid engine supercars and cargo space was not a concern, but I have a hard time picturing how this would work in a more practical car.

If we remember triddles (RIP) like most other converisons, the battery pack was basically split half and half in the front and rear. This is by far the most common configuration for conversions. Now before anyone jumps on me and points out that I just gave an example of a conversion and not OEM that was an EV from day one, consider what goes into designing a car (indeed many of the same considerations that go into a conversion).

Most if not all cars today are built around the occupants. The passenger compartment is virtually identical functionally from one car to the next in the same class with the passengers being in the center, and the powertrain/cargo related zones being fore and aft of the cabin. This is not by accident. Safety, comfort, and stability as well as being as compact as possible while not sacrificing interior space all play a role.

My question is, where can you fit a battery that has enough energy for 100 miles of range in a car like this? All in the front, and the car has a forward weight bias. All in the rear gives a rearward weight bias. All under the floor raises the overall height of the vehicle for the same amount of interior space and thus increases aerodynamic drag so that net efficiency (and range) is reduced. A center tunnel would have to be very large to hold enough batteries and would sacrifice interior seating.

The way I see it, the only practical way is to install the batteries through out the car in several different modules to maximize interior space, keep exterior size at a minimum, and have the best possible weight distribution for acceptable handling.

So basically, I'm still waiting for proof of concept.

Dang that was a long post, sorry guys.

 

[major]

Don't be ridiculous,

Lighten up, Kiwi,

Ridiculous? Like

fast recharges in seconds

No reason you can't have it both ways. EVs capable of home recharge and exchangeable batteries. I favor overnight night charging. I don't use my car while I'm sleeping anyway. And that utilizes off peak power from the grid. Actually should cost you less than daytime charging.

Tell you what Major, why don't we just let the future decide? Meet back here in 2029 ok?

I hope we're around to meet. I'm sure there will be technologic developments in the next 20 years which make this discussion seem stupid. Batteries small enough to fit in the glove box? Exchange of electrolyte instead of the whole battery? Magnetic recharging? Who knows?

For present day technology, battery swapping is valid. I did a race vehicle where in the pit stop, 1200 pounds of lead-acid batteries were swapped in 17 seconds. And that is a lot faster than what was possible with a pit stop recharge, by far.

Batteries are like fuel tanks. How attached are you to the gas tank in your car? Why would you care if a robot swapped your fuel tank at the gas station instead of you pumping gas into the tank? It boils down to the infrastructure which develops to support future transportation. Various approaches should be explored. The more the better. Something good is likely to shake out in the end. Hopefully before 2029.

Regards,

major

 

[judebert]

Shai may have a few ideas that some of us see as crackpot, but let's have a look at some other people with so-called "crackpot" ideas:

You forgot my favorite, John Holland. Although Sikorvsky runs a close second.

Anyway, we've all got crazy ideas. That's why we're here, in this forum. (I can't even remember how many times somebody's looked at me like I've grown an extra head when I tell them I only get 15 miles out of my EV.)

One elephant in the room that no one seems to be mentioning is the problem of making a single battery pack in one location of the car.

I'm not sure that's as bad as you make it sound. Unless we come up with some way to get the cars parked in exactly the same location every time, that robot is going to be designed with some leeway. Either an auto-centering battery pack (like maybe tapering it) or some robot scanning is going to be required. If you go with scanning, why not scan for more than one pack?

I like the idea of battery swapping. It's too much of a problem for me to solve, but it's well within the capabilities of a scientific community that can hit a moving target on the next planet over and build self-driving cars.

 

[KiwiEV]

Major, I don't have to lighten up if I feel my character is being attacked. Perhaps I over reacted but with reading text I can't tell if you were being sarcastic or not in your initial response, hence me advising you not to be ridiculous with your idea of homes offering 60 second recharges. If you weren't being sarcastic I apologise. Sarcasm has always been hard to detect or imply on message boards.

When I referred to "seconds" in fast charging, I was talking about the small battery packs A123 sucessfully charged on their test benches last year. It'll certainly be seconds for laptops and cellphones etc, but most likely several minutes for cars. At this stage anyway.

As for Fast Recharges vs Battery Swapping? I still beleive fast recharges will make battery swapping obsolete but we're allowed to disagree. I guess that makes me a crackpot with an idea no different to those other crackpots Jlsawell listed above!

I heard an interview with a Tesla engineer who said they now have 1 hour recharges available for the roadster with high voltage/amperage charging stations - that's with today's technology!

At this rate I see it taking over the incredible logistical/developmental hurdle that is battery swapping - for better or worse I see fast charging as the future. So do the crowd at www.EVcast.com which is where I get my info.

You're right, we will probably look back at this discussion in 20 years and laugh. For the mean time, place your bets people!

 

[major]

If you weren't being sarcastic I apologise.

Of course I was being sarcastic. That's what I thought the was for. I know your mate does not have a 1.8 megawatt outlet. Who does? That was my whole point. What power levels are required to fast charge EV batteries in seconds? Megawatts. I suppose we could recharge those EV batteries in milliseconds if we had gigawatt chargers. I guess that is the smiley for sarcasm.

Regards,

major

 

[KiwiEV]

Of course I was being sarcastic. That's what I thought the was for. I know your mate does not have a 1.8 megawatt outlet. Who does? That was my whole point. What power levels are required to fast charge EV batteries in seconds? Megawatts. I suppose we could recharge those EV batteries in milliseconds if we had gigawatt chargers. I guess that is the smiley for sarcasm.

Regards,

major

Hehe, I forgot to show a picture of my mates place:

And that's nothing, you should see his home theatre system!

 

[jlsawell]

Just an idea, I've no education in electronics but lets see if this is possible:

You have two sets of ultracapacitors: one in your car to charge the batteries as fast as is safe. The second set is in your garage/public charge point.

So the static ultracapacitors are constantly charging from the grid. Like a parking meter they have a graph showing how charged they are. Drive up to a full one, plug in and BAM - the charge goes from the static ones to your car.

The car UCs then trickle charge your mobile batteries while you drive.

On the charge post, the graph goes from "green" to "red" and anybody wanting to recharge knows to find another charge post until this one goes green again.

You might have to sit for 5 minutes or so waiting for a post to go from "amber" to "green", but that's just like waiting for a parking space. Or you could circle the block looking for a green one.

Is that how ultracapacitors work or am I "living in the future"?

 

[david85]

I think I understand what you are getting at, jlsawell.

In theory it is possible, but the energy stored in those supercaps in the car would have to be comparable to what is stored in the main traction pack otherwise you would only get a small amount of recharge. So far, no such capacitor exists. If it did exist, then you could simply eliminate the chemical battery completely and use solid state controls to manage a bank of supercaps. Now you can recharge in under 10 seconds with no moving parts, but like I said, no such capacitors exist.

However, you still have a good idea there if we were to change it slightly. One problem with dump charging thats already been mentioned is the lack of electrical power to feed all those amps even for a few minutes. If the charging station had a huge capacitor bank that can slowly accumulate energy off the grid (like you describe), then dump it into the car as fast as possible for the battery to accept. This would probably give charge times of 10 minutes or less with today's 3rd generation lithium batteries.

I do like the simplicity of your charge meters though. The nice thing about this, is cities can get into the business of actually offering charge stations instead of just grabing money for parking downtown. You would still pay, but at least you can get something in return besides just a place to park. I think its a much more fair and sustainable arrangement for citizens and municipal governments in the future.

 

[Technologic]

How to kill this battery swap robot and make his time a complete waste of government money?

The fact that you're changing out your car's brand new $20,000 battery for a battery at a gas station with unknown quality.

*kablooooooooey* your idea is dead... thanks for wasting $1 million of taxpayer money.

Unless these people are also going to service your electronics for free as well... this idea is about as solid as a bowl of applesauce.

What a bloody waste of time this crap is... give ME the money to research for god's sake... I'd show you ridiculously badass things >,>
As if every car will have a standard pack size to just swap in anyway... stupid asshole. Am I the only person that gets sharp desires to punch these people in their face that are doing these sorts of things?

I want Tesla's CEO a good foot away for 2 minutes... make things all "square" and even for being such a dense troglodyte

 

[david85]

Actually, the whole idea is that you don't own the battery, Aggasi's company does. What you pay for is not the electicity, you pay for the miles of usage. Aggasi is trying to take the marketing idea of cell phones and paste it on cars. The short answer is you get locked into a contract and pay for the miles weather you use it or not. I suspect there will be hidden fees as well.

When you consider all of this, I am convinved that there is no future here and this is almost as bad an idea as fuel cells. Its easy to understand the idea of swapping batteries because most people simply don't understand the structural considerations that go into a car. I tried to explain, but I guess I didn't do a good enough job.

The idea of simply changing batteries is a powerful catch because we change batteries in house hold appliances all the time. Its an easy idea to visualize in your head. It works in toy cars, so why not scale it up to full size? The reasons why this won't work are more complex than Aggasi's idea, so its an uphill battle to explain why this is simply won't work at any price.

Personally I would only need 0.5 million (canadian) to get a good thing going.

 

[Technologic]

The idea of simply changing batteries is a powerful catch because we change batteries in house hold appliances all the time. Its an easy idea to visualize in your head. It works in toy cars, so why not scale it up to full size? The reasons why this won't work are more complex than Aggasi's idea, so its an uphill battle to explain why this is simply won't work at any price.

Personally I would only need 0.5 million (canadian) to get a good thing going.

It seems like idiots get "caught" by everything.

If they saw how large that pack is they wouldn't think swapping it out is practical... and the last thing I want is to be under a contract to have my batteries taken care of (battery insurance sounds like a giant waste of money and a fast way to stagnate the technology)

Hell I'd work with $10k and could get some $800 MSRP high amperage (500v 600A) AC controllers out there selling at that price...

But noooo let's toss $250 million to Tesla to produce a car no one on the planet can afford. Wonder how worn out his wife was after "making" that deal.

 

[david85]

Maybe I'm just on a one track mind, but I'm trying to think of a situation where spending cubic amounts of money (public or private) resulted in good, meaningful advances in technology (or other measure of human progress).

Didn't the first PCs start on some one's garage? Powered flight? Information tech? Maybe you just can't force progress with money alone, hard to believe isn't it?

One of my favorite rock tunes from the radio laments:

"where have all the good people gone?"

(haven't heard it in ages, actually)

 

[Duncan]

Hi David,
Most advances have taken gobs of money,
Computers - the IC's that make them work took billions to develop
Flight - materials, engines, avionics,

The first "proof of concept" was not so expensive but getting it up working

Wright Brothers
I bet they spent several millions in 2009 dollars
They invented/Developed;
Wind tunnels, Air-screws (it took years for others to achieve their efficiencies)
Light weight motors, control systems

IC engines - billions in materials research alone - remember sidevalve engines, they were developed because the valves kept breaking -
Modern engines tend to be 4 valve - some of the early engines were 4 valve because of the limitations of the available steels

I can't think of anything that has been developed (as opposed to adapted) without lots of money
Most of the really big improvements were made using public money

 

[Technologic]

Hi David,
Most advances have taken gobs of money,
Computers - the IC's that make them work took billions to develop
Flight - materials, engines, avionics,

I'm pretty sure Computers never had basically any government subsidies... I think david was referring to technologies that have DEVELOPED from subsidies... and I'm at a loss to think of a single example.

Wright Brothers
I bet they spent several millions in 2009 dollars
They invented/Developed;
Wind tunnels, Air-screws (it took years for others to achieve their efficiencies)
Light weight motors, control systems

The first plane they had built was a glider that measured 16 feet from wing tip to wing tip. It cost them $15 to build it. The gasoline-powered plane they flew at Kitty Hawk cost them less than $1000 to build

You guessed wrong. Not even close to that much

IC engines - billions in materials research alone - remember sidevalve engines, they were developed because the valves kept breaking -
Modern engines tend to be 4 valve - some of the early engines were 4 valve because of the limitations of the available steels

Almost all of that money has been private company investments? doubt it? show me an example of a "great leap forward" that was funded entirely by the government (or even 50%). It's almost a necessary fact that every grant is going to fail from the start to meet even 1/1000th of the expectations.

How to advance technology through subsidies? give out prize money (huge prize money) to college kids working in their garages for coming up with something amazingly marketable. I bet that'll work

I can't think of anything that has been developed (as opposed to adapted) without lots of money
Most of the really big improvements were made using public money

What public money was used to create anything "big"?

Do you think the lightbulb and electricity were "big" or do you think adapting the designs of Edison's dam to build the Hoover dam was "big"? Believe me... Edison's work was bigger... and not a dime came from the government for his initial research.

I'm really curious what you think "developed" even means. If you mean "invented" you are unbelievably wrong. Even freaking NASA was taking their cues for rocketry from the writings of college students who built scale models.

Believe it or not, a guy in a garage built Microsoft and Apple, and almost every other huge company still in existence. It wasn't government grants to solar resellers or $5 billion/year spent to try and get even 1,000,000 cars on the road that use partial electricity (yes we ALL know that much money would buy the cars outright... on today's terms...)