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Discussion Starter #1
Don't know if anyone has seen this thing but it seems interesting. At least from the standpoint of increasing mileage and if not on the Lotus then maybe a daily driver. I know that for the money the supercharger options would probably add more HP per $ spent. I was wondering what people here might think of this:

Electrocharger / Retrofit Hybrid :: Sigma Automotive

If the larger model did provide a 60% increase in fuel economy that would take the elise from 30MPG to almost 50! I would be interested in that.
 

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smoke and mirror

that will do nothing for highway mpg, and only help in stop and go throttle tip in.

i am skeptical when they claim "regenerative braking" and it has none - other than engine braking (load on the engine via the chargecycle)

it would be a fun little something to put in, say, your old fiat 850...

all they are going is replacing the alternator with a motor/generator and little battery power source. supposedly the motor logic will control when and how much it engages drive on the crank shaft, but it won't be much and or for long.
 

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Hmmm...assume for argument's sake it's a 10hp electric motor. There are 746 watts/hp, so that's 7.46kW equivalent electric power. Assume 85% efficiency, now it's 8.77kW of electricity. At 12V that's 731 amps. :crazyeyes:eek:

You'll need a bigger alternator, and a pretty good battery.

The on-board energy for the ElectrochargerTM comes from the Super Capacitor Battery Pack (SCBP) that provides up to 600 amps at 48 volts to the electric motor for acceleration durations.

600A @ 48V is about 33hp at 85% efficiency, which is significant for a little bitty car I guess. Still, you have to recharge that beast while you drive. Sounds like you'll get in trouble (i.e, wear down your battery) if you accelerate much.
 

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the 600amp is battery capacity - not motor rating

i suspect based on the photos that its about a 3hp motor. and DC, not a poly phase AC motor - so it not all that great of an engineering concept. ...imo
 

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Visuals vs numbers aside... I agree there's some funkiness in the system. The FAQ page, for example, claims a three second minimum drop in 0-60 times and three seconds off the 1/4. Interesting claim, but completely irrelevant. That's a snake-oil pitch in itself.

But there's some validity to the numbers... what few there are. If we were to assume that 600 amps at 48v is the capacity of the system it would contain enough energy to provide around 33 hp for one hour (assuming 85% efficiency.) That's not an insignificant amount of juice. But it doesn't make much sense. A 600 amp 48v storage system is large, expensive, and really heavy.

Larger Odyssey AGM batteries that weigh 75 lbs are only about 85 amp capacity. You'd need more than 10 of those to get the same capacity. Besides super capacitors aren't really designed to store 600 amps worth power. They're just designed to provide that much when/if needed in short bursts.

So the system is designed to provide acceleration assists for two minute periods (with eight minute recharges) which would indicate that the 600 amps @ 48v is how much power the system can output instantaneously, which is still only 33 hp-worth. A much smaller pack (or bank of super capacitors) need only be capable of storing 20 amps (or a bit more to keep from going below useful, safe capacity) That's now much cheaper and lighter.

Is any of it relevant? I suppose so, you're now talking about a 33hp assist with max torque just off zero rpm. That's valid. With their performance claims? I dunno about that. Can a tiny motor generate 33hp? Maybe... The more limited the duty cycle the more possible it could become. It's common to rate electric motors at vastly lower continuous ratings then their peak capability. But could a 15 lb motor be capable of a 33hp peak output for 2 mins? Hmmm... I dunno. Possibly, but it would be pushing it.

Does the thing in the pictures do that? Who knows... I always wanted to a do something a bit similar (an electric assist system) through a motor mounted in place of the starter motor.
 

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Discussion Starter #6
OK sounds like you guys know a lot more about this....actually that is not saying much as I have no clue about electric motors and amp ratings etc. However if you did have an electric motor essentially "Pushing" or helping to push the engine drive train via the belt, wouldn't it take off some of the load and improve mileage??

What if they did have a larger motor and battery/capacitor?

And it does seem like if you sat in city stop and go traffic where you engine, at idle, was at least giving some charge to the on board system then you could use some of that stored energy later. I know there is no free lunch when it comes to energy but I guess It's always nice to look for a better/newer technology.

Maybe "to good to be true" applies here but it sounded like a great idea to me....then again let me refer you to my own quote:
"I have no clue about electric motors and amp ratings etc"
 

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Discussion Starter #7
Larger Odyssey AGM batteries that weigh 75 lbs are only about 85 amp capacity. You'd need more than 10 of those to get the same capacity. Besides super capacitors aren't really designed to store 600 amps worth power. They're just designed to provide that much when/if needed in short bursts.
What about something like the EEstor capacitor. I know it is not on the market yet but the performance claims from the company seems like it would be the perfect combo for this.....if as you say they had a small enough motor that would work.
 

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Yeah. I mean, that's what hybrids are, essentially (Prius, Escape, Camry, Insight, etc) The whole idea behind a hybrid is that you're using the power very elastically. There's no free lunch... you're just saving some for later.

Hybrids essentially try to keep the internal combustion side running at its most efficient. That doesn't translate into relevant driving dynamics. For example, an engine idling is at its most inefficient when stopped (zero mpg). But you have to stop sometime. Similarly, an engine is very inefficient just off idle. But you have to start from that stop. So the electric part of the drivetrain is used to make up for the inefficiencies. Store a little power when the IC side is efficient and then use the stored energy when the IC side is inefficient. Like a rubber band.

A system like the Electrocharger could work. The question is how well? From a pure consumption standpoint, you have to balance the extra weight of the assist system and subsequent inefficiency with the gained efficiency from shifting around the way the IC power is used.

From a money standpoint, it may never make sense depending on how efficient the system becomes and its resultant fuel savings compared with the cost of the system. Does $3000 worth of assist really save you $3000 in fuel costs?

A system like the Electrocharger really wouldn't do anything for steady state cruising, where most IC engines are tuned for efficiency. It's why hybrid vehicles don't get much better highway mileage compared to their IC counterparts. The hybrid Camry gets 34 mpg while the non-hybrid will return 31 mpg. But in stop and go city driving the system starts to shine. Now you're saving power for use in acceleration, where IC engines are piggish.

Ultra-capacitors are designed to augment or take the place of battery packs. UCs are lighter and are capable of delivering much greater amounts of short burst electricity than batteries. It would definitely make an assist system more relevant as far as a weight and performance is concerned. Cost would be the big issue. And ultimately at this time, capacitors really can't store the amount of energy that a battery can. They can release large amounts in a short time, but they can't store large amounts. So UCs are used as small energy sources or as buffers for the batteries (since small batteries can't release large amounts of energy in a short period of time).

Think of batteries like large containers with small outlets. While ultra-capacitors are small containers with wide outlets. So, in some cases the battery will slowly charge the UCs which will then dump very quickly into the powertrain.

I like the idea behind the Electrocharger. I mean, why not? It's easier to retrofit to an existing vehicle than the starter motor idea, or re-engineering an entire transmission. But will this particular device work? It really all depends on that motor, and the capacity of the power system...


However if you did have an electric motor essentially "Pushing" or helping to push the engine drive train via the belt, wouldn't it take off some of the load and improve mileage??
 

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Discussion Starter #9
I like the idea behind the Electrocharger. I mean, why not? It's easier to retrofit to an existing vehicle than the starter motor idea, or re-engineering an entire transmission. But will this particular device work? It really all depends on that motor, and the capacity of the power system...
Thanks for all the info. I do like the idea of something that you can retrofit, as opposed to buying a new vehicle, if it really could give 60% better mileage. Guess that is what really caught my interest. I knew that in freeway driving this thing would be useless but here in Tucson it's stop and go street light to street light. Guess the best approach as usual on something like this is let a few people try it out, if it is ever really sold, then check for consumer feedback.

Who knows, maybe someday, someone, at sometime will make something like this work.......and it will make you loose weight and gain muscle while increasing you gas mileage as wellrotfl
 

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I don't think you'd get anywhere near a 60% fuel improvement. That's more than the difference between average city mileage figures and highway figures for an average car. Hybrids barely are capable of lifting city mileages 50% of what their non-hybrid counterparts do, in the city, and they have the benefits of CVT transmissions, the ability to shut down the IC side completely on coast or at a stop, the ability to run on the electric system alone for low speed brief spurts, a larger electric storage system, and optimized fuel programming, etc...
 

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Two things:

First the rubber band analogy is only partly right. part of what hybrids do is trade energy around in order to be efficient when it is used. Regenerative braking is one of the places where they win. While this thing might not have real regenerative braking, real hybrids DO have it. So instead of heating the brakes and losing the energy out of the system, regenerative braking takes that energy and stores it for later.

The second thing is that I wonder about the belt! how many HP is the belt rated for? And while we are at it, all of the pulleys. Assuming that the electric motor actually has a usable amount of power, is the belt and pulley system good for it?
 

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I'd imagine that the pulleys aren't a big deal. You're connecting directly to the crankshaft through a custom sprocket. And I was skeptical of the drive belt idea (thinking that a chain would probably be more robust), but then realized that a lot of motorcycles are belt driven. So it really depends on that belt. I suspect a belt could work.

I'm not endorsing the thing, though... I'm generally a skeptic in the face of little information. And information specifics is exactly what the site doesn't have. Lot's of sell, but no hard data.
 

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the 600amp is battery capacity - not motor rating

i suspect based on the photos that its about a 3hp motor. and DC, not a poly phase AC motor - so it not all that great of an engineering concept. ...imo
That motor is small, but giving them the benefit of the doubt, it's *possible* they designed it for momentary bursts of power, so it might put out quite a lot of power for a short time. I still doubt the setup will do nearly as much as they claim.
 

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Availabilty, Winter 2005

I can't wait!!!

and the price is still TBA
 
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