Viability of Project Better Place

I suspect the upfront investment costs would be astronomical. The above statement is kind of like saying that "Apart from the fact that I'm heavier than air, I see no serious weakness in the concept of floating to work instead of driving a car."

There's a lot of "would"s and "could"s in the proposal.

A typical gas station on the highway probably has enough gas in stock to fuel several hundred cars a day. The above proposal would require all these stations to have enough grid service to provide that much energy, to continuously recharge that many batteries a day.

But newer batteries have the ability to be recharged fast, so if the station has the grid capacity to deliver that much energy, the whole battery-replacement scheme becomes unnecessary. In effect, it's a solution without a problem. It looks to me more like a scheme to raise money than a serious attempt to solve a problem.

Bottom line: You don't need to replace batteries if your batteries can be recharged fast, and the newest batteries can be.

 

The jury is still out in this debate. I can argue either side effectively. I suspect swappable batteries will be a transitional technology, which if used, will be replaced by fast charging storage devices.

Tom

 

Consider a gas station on the freeway. It has maybe 15 pumps and a car pulls in every minute. Now convert it to your system. First, the robot battery switcher is a LOT more complicated than a gas pump, so will need more redundancy. Plus a station with 15 pumps can continue to operate if several are out of order. Now assume you can put an adequate charge on an (older) battery in two hours. One car each minute arrives. You are simultaneously charging 120 batteries. This means you have 120 charging units and 120 complete battery packs sitting there all the time. Plus some extras so you can take bad units out of the line for repair.

What I am saying is that solving these issues is more difficult than fast-charging where the battery remains in the car.

And if ultra capacitors are developed then the whole debate becomes moot because they can be charged faster than you fill a gas tank now. I personally think ultra caps are a decade away, but some folks think they are a year away. Your scheme will take at least a decade to develop if we begin now, and I don't see anyone with the capital now. So fast charging looks like the winner again.

The forward-thinking program being started in Israel is using fast charging, not battery switching.

Now let's imagine someone has the capital to start this program: They'd be better off to loan A123 batteries to customers for free, and fast-charge them at the stations, than to build several hundred thousand robotized charging units for battery switching. They amortize the cost of the batteries with the price they charge for charging, just as in your system, but fewer batteries are needed overall and the cost of switching is eliminated.

This may be my last post for a while. See you all when I get back on line.

 

...

Very interesting concept. My thanks for your effort to give an EV grid some more thought and bring it to further discussion, Sola.

I have a comment about battery location. I know many are already well aware of this but it is important enough to bring up again. I don't know much about current PBP plan.

If the battery were to be quickly exchangable, it certainly must have a different and more accessible mounting than the Prius. It seems that even though the battery in a hybrid is smaller than that of a dedicated EV, most hybrids have struggled to some degree to find suitable semi-permanent storage. Space allocated under the rear seat by design seems to work best. But conversions, such as the Camry, already move the battery back and give up trunk room for even the smaller hybrid battery. Many EV designs tend to spread the batteries in more than one location, unfortunately toward either end of the auto.

Therefore one of the downsides, to even the Camry, is that the heavy batteries are often moved back, or ahead, further from the center of rotation*. This is very undesirable from a handling standpoint. Once such an automobile begins to spin, it is more difficult to regain control and aim it properly down the road. Besides 50/50 balance, this is the main reason why mid-engined cars handle better, with the majority of weight centered between the wheels. This mass centered concept is even an advantage with locomotives which weigh about 400,000 pounds. The 5000+ gallon tank is suspended by centering it low between the wheel trucks.

So, in view of this, it would pay to suspend a heavy flat-pack of batteries right off the bottom of the EV directly between the wheels. Exchange would mean dropping down and out with a forklift, or with a moderate (10 inches?) drive-up ramp, release straight down and the auto is moved ahead to a re-load position.

The ramp principle would also allow at-home recharge battery exchange were that ever a possibility ...and I think it is. As an example, wind generators work better during the day when an auto is also in use. Solar recharge is definately daytime. I see it as modelled similar to choice of propane cylinder exchange-or-refill (Blue Rhino - Propane Tank Exchange, Grills, Heaters, Mosquito Traps, Fireplaces, and More).

*In other words the angular momentum is increased. It is analogous to comparing a dumbell with the weights at far opposing ends of the handle as to weights slid together at the center. One can readily imagine that rotating the dumbell with the weights at the far ends will cause a greater flywheel effect than will the same weight grouped towards the center.

Some folks have brought up some good points on how ponderous an exchange might be. It seems as though it could be as time consuming as getting an oil change rather than a fuel fill. How can it be accomplished more quickly, yet simply? Drive up and click in place?


...

 

I think daniel makes a great point. Think about it this way: how many battery packs would need to be in circulation per vehicle to be sure that there's always a charged battery waiting for you at whatever station you visit?

Say it's 2. It's a lot more than 2, but say for example it's 2. With some sort of fast charge, you could spend twice as much on each battery pack, and be even. Only now, instead of a robotic battery changer, robotic storage, and a car with an easily swapped battery, you've just got a charging station. So you've saved on infrastructure, vehicle design, and real-estate, and you can put charging stations in a lot more places (including gas stations, malls, workplaces, and at home).

PBP requires a huge amount of capital tied up in idle batteries and robotic battery changing equipment, all specific to one company. And if the company goes belly up? You're completely SOL. Sounds like a great sales pitch for a guy to get some funding, but a lousy way to make the world a better place.

-SpruceMoose

 

This is hardly a new idea. Swap stations were discussed back
in the seventies, I think...
.
And you keep saying "see the website", without providing any
reference as to where it is.
.
_H*

 

Swap stations have not only been talked about the electric cars of the early 20th century relied on them. "The Electric Vehicle and the Burden of History" is an excellent book that details the golden age of electric vehicles and the business models of the different companies. Most of these companies developed networks of battery swapping stations around a specific city.