[Philosophy]

I really think this is a good idea.

I would be willing to go in on a group buy if someone knows how to design an aftermarket addition to the Insight that has
1) its own battery pack that drives
2) the rear wheels and
3) works in conjunction with the fwd on it for electric assisted 4wd and
4) provides an all-EV mode using rwd.

This would truly make the Insight like none other, and further develop its ability to get superior gas mileage. This means leaving the gas motor alone, yet adding additional functionality - I'm not sure about the logistics because I'm not very mechanically inclined.

-Phil

 

[Armin]

best way to do EV only mode

I think we are a few generations away from something you could go out and purchase in a group buy. I also don't think it will ever integrate with Hondas IMA, since we won't get information about their communication protocols.

But, I agree that this is the most feasible way to get EV-only mode and grid-charging in an Insight: Make a completely independent EV-drive for the rear wheels, using two wheel motors and separate battery, drive and controls.

So who has too much time on his hands?

 

[Insightful Trekker]

Re: best way to do EV only mode

<snip>

So who has too much time on his hands?

And a BIG wad of money in their pocket! R&D even for a home brewed "new path" (e.g. rear electric w/front ICE) project will be expensive.

The electric conversions I read about on the Net necessarily use 12v lead acid batteries due to cost. And their range is reported less than 60 miles. Although slower = more distance for most any electric vehicle. Yes there are a couple reported to _plan_ to use an advanced battery, but completion is still hanging.

I've recently thought about an electric only Insight. It's do-able with off-the-shelf components for under 10K$. But would likely have a range of less than 50 miles with top speeds of 60 MPH. For me the speed is ok but the range needs to double. Which would necessarily require advanced batteries easily costing 2x more than the whole project by themselves and still have a "limited" service life.

Until something better than NiMH comes along at a cost similar to lead acid its still impractical for me.

 

[Philosophy]

If you managed to create decent controls, you could use the electric component in the rwd to get up to speed, then crank the engine to maintain speed even without fwd/rwd compatibility, you could also have 4wd at low speeds with both propulsion systems running.

I could even see the ICE trickle charging the other battery pack through the power outlet - as long as it doesn't suck as much power as the air conditioning, it could theoretically keep the battery maintained.

The purpose would be to increase fuel economy by creating a way to accelerate up to speed without any gas -- which is the time which most gas is burned, until you get up to speed & get your lean burn.

I know the first thing people bring up is the cost of batteries, but has anyone seriously considered building their own NiMH out of commonly available components like the battery packs from portable phones? I just bought a hover-soccerball (straight out of Back to the Future) that came, for $12 or something, with 2 separate NiMH packs that keep it going for ~35 minutes.

I know that most of the people on this board have been around and heard all of the different crazy schemes that people get in mind, and generally tend to be pessimistic, but this idea really seems to be more realistic than the others because it isn't as extreme or unworkable as the other ideas.

-Phil

 

[Mike Dabrowski 2000]

I am happy to see this topic come up again. I started a thread about putting motors on the back wheels of the Insight, way back when I first became a member of the other Yahoo Insight group.
After a close look and several years to ponder this issue,I have settled on several approaches that one could use.
1. The best in my mind is to use as many of the Insights features as possible, The IMA is mechanically a beautiful machine, and should be used as is. The only problem with the present Insight control system, is that we as the driver, do not have real control of the electric motor/generator. We can see the hill coming up, and can best decide how to use the available assist, and when to convert kinetic energy back into charge. I wrote an unanswered letter to honda explaining that I would be willing to pay $1000 if they could provide hardware/software that would allow direct control of the charge assist. I had invisioned that the shift knob would be rotatable, with a spring return to center. In the center position the car would switch to automatic electric drive, as it is configured now. A twist to the left would charge the pack with regeneration in proportion to the amount of twist. A turn to the right would kick in the electric motor. All of the needed minimum charge and maximum temperature safetys would be active, so one could not hurt the motor or battery pack.
That would have been my first choice.
No thank you Honda

2. We can hack into the control buss.
Since no CAN software people have expended the effort to get on the Insights internal control network and figure out what the assist/regen codes are. With that information a simple PIC microcontroller program would allow us to jump on the buss and control the motor generator through the cars own control system.

3. Replace the motor controller with a stand alone industrial 3 phase brushless motor controller with regen. A likely problem with this approach is that the gas engine control system is tied into the BCM and MCM controllers in ways that we do not fully know, and may not work if the module is not there.It may work fine, it would have to be tested before this approach was tried.

4. Get a brushless or brushed Dc wheel motor , and adapt it to the rear wheel suspension system, and have a second battery and controller.

5. Add an offset sprocket to the rear wheels, and mount an electric motor with chain or timing belt drive to the wheel asembly.
The ability to accelerate with pure electric, and to maintain speed up hills using electric assist without stepping down on the gas, could change the average MPG numbers into numbers that even our milage champs would be happy to see. I really think they should provide a manual electric mode on all Hybrid cars as an extra priced option for the serious drivers that want to maximize their milage and performance.
Mike

 

[Insightful Trekker]

There's another recent thread in here with a similar dream.

However reality is a cold shower.

Its simply a function of battery energy capacity and cost. Until you
look at a real world application with all the normal losses of
efficiency it takes a HUGE battery power supply for any reasonable
distance & speed. The 120 cells of our IMA pack are woefully inadequate
for a useable electric only mode. The cost "bare" as available at the
Panasonic web site last time I checked were $800 - 900. And for electric
only mode "upgrades" for the motor and controllers will be necessary
too. A 100% duty cycle system requires better cooling that what our
Insight's are equipped with.

And easier "way" to approach the "problem" is to look at existing
electric vehicles to determine battery capacity and resulting range.
Then convert this established capacity to another battery type say NimH,
and get ready for the shock. It's gonna cost BIG time. And cost
something similar when the pack is "spent" at the end of its service
life.

http://www.austinev.org/evalbum/

A 100% electric conversion for the Insight with top speeds of 75 MPH
(at a serious range reduction) or a moderate speed of 55 MPH and a range
of 100 miles is within current technology is do-able for around 30K$ +-.
And a limited service life battery pack that will require replacement on
a routine basis at a cost of many thousand dollars each time.

I doubt there will be many buyers.

Other technologies such as ultra caps, LiIon and other battery types
are yet proven and or have serious safety concerns. None are lower
cost then Lead acid.


Finally, perhaps the most serious "bottom line" is that there is not
enough electric generating capacity to replace the energy we consume as
gasoline. Any widespread conversion will have expensive consequences too
e.g. power plant construction, transmission lines upgrading, etc.

HTH!

 

[Philosophy]

This isn't really a full electric conversion though.

I saw on the site you linked that there had been a full EV conversion attempted with limited success and a cost of US $20k, that's just too much.

I'm talking about an Insight-style further compromise that would make it lean more electric in the gas/electric hybrid continuum, an upgraded electric mode with limited range, less batteries, but more functionality and ability to use 4wd at low speeds.

I agree a fullscale conversion is probably not worth it. Ontop of that, I'm not convinced that putting something on the grid in Kentucky (which is the coal state, and burns coal to produce all of the electricity here) is a positive environmental step. It's more about the additional features and special modes it could have, even with just another Insight pack used solely for that (then you know all of the things would be compatible).

-Phil

 

[Foxpaw]

Ermm, that all sounds more complicated than it likely needs to be - I doubt microcontrollers would be necessary at all. Manual control of assist is likely a very easy and simple thing to do, it's simply something we haven't figured out how to do yet. Instead of "hacking into the bus" it will more likely involve wiring a single switch like the "max regen" button. We just haven't figured out where the wires have to go yet.

 

[Yves M.]

I think that to have rear wheel drive, we would need to have some "wheel motor" sold on the market. I am not aware that they can be bought.
Because of the space available and not to cut the body structure.

I heard that a China company will build an electric car with "wheel motors". Then there could be those wheel for sale maybe.

 

[Armin]

Wheel motors

There have been various EVs with wheel motors, this is not the first one.

Anyhow, I'd like to summarize the effort we're discussing like this:

"Build an electric drive to the rear wheels that is entirely independent of the Honda IMA system and directly controlled by the driver."

Short of Honda suddenly releasing all their sourcecode into the public domain, we can't expect to integrate with IMA. Besides, the rear-wheel drive will be very helpful without that: You get EV-only mode (only you use a manual control, not the gas pedal to control power), 4wd and manual assist.

So I'd suggest to skip looking at the IMA and start looking for suitable wheel motors!

 

[clett]

This idea has been considered on here before, and I think it's a great idea.

I see "Electric Assist" as being the next big think in fuel economy improvements - and represents the stepping stone between today's hybrids and tomorrows plug-in hybrids.

People are often bemoaning the cost of such a conversion, so I'd like to point out that it could potentially be done for not nearly as much money as most people think.

First up is the cost of the battery. Assuming we are only intending to put a small assister in, let's aim for a 25kg battery pack. I would make it up with AA sized 18650 Lithium Ion cells (shown below). The latest Sony 18650 cells are 220 Wh/kg and weigh about 44 grammes. There are loads of places on the internet where you can buy such 18650s in bulk for about $3 each. Thus, our 25kg assist-pack would be made up of 568 individual cells for a cost of about $1,700. Energy storage would be 5.5 kilowatt-hours (EV-mode range 33 miles; Assist-mode range 66 miles). Max power output about 10kW.

some 18650s

Now for the assist part. I reckon the easiest thing to do would be to monitor throttle position and gear selection and then automatically add as much power from the assister as the engine is supplying. In effect, the car would feel half the weight, and fuel economy would double, and the driver wouldn't have to worry about constantly adjusting the assist level manually.

However, I think the wheel hub idea is where the costs are going to add up. It's a great solution for retrofitting non-hybrid cars, but I still think (as I was suggesting here), that it would be cheaper to just use the IMA motor already installed. Yes, the initial working it all out would be complex, but the Priusplus folk have managed it already for the Prius, and once it's been cracked for the Insight it could be a fairly cheap conversion.

Finally, for anyone doubting that amazing EVs can be made on the cheap, check out Peter's excellent Solar van - 100 mile range and it doesn't even need to be plugged in!

£9,000 all in!

 

[clett]

By the way, thought I'd post again the picture of the Insight with the wind-charging mod - (just because I like it so much)!

Back to topic though, it means that at least one person seems to have managed to crack the CAN bus issues. Article on the conversion here.

 

[Foxpaw]

I don't quite understand how you drew that conclusion. I'm not entirely sure what the "CAN bus" refers to, since I don't think that the IMA system would have any data buses that could be accessed externally. All that should be required to charge the IMA externally is power to the BCM (and possibly the battery pack's fans) so it can properly keep track of the SoC.

 

[Insightful Trekker]

<snip>

Thus, our 25kg assist-pack would be made up of 568 individual cells for a cost of about $1,700.

<snip>

AFAIK a major design consideration for a battery pack array is the number of cells. Any individual cell in an array has an impact on the whole. For longevity there is a balance. The 568 cell array will be a tough balance to maintain.

In regards to the windmill Insight charger I've seen it around for a couple of years too. AFAIK the windmill shown only has a 12v capacity so something smells fishy.

All I am asking is show me. The one of a kinds give reason for doubt especially with the bogus 12v windmill charger. All of the proven EV conversion on the link I provided are of the 12v lead acid type. I can't imagine its simply because they "like" the lead acid batteries better. :wink:

HTH!

 

[Philosophy]

I like that everyone has been discussing the different approaches other people have taken, but I really think that this rear wheel drive completely separate from the current drive train is the way to go because it simplifies the entire situation. Also, keep in mind the solution should be a new feature that provides benefits above and beyond the costs it extracts in resources for creating it and losing storage room / adding batteries.

Another solution I had in mind was adding a new wheel completely independent of the other wheels and not messing with the system at all.

If there were a 5th wheel located centrally and ahead or behind the current rear wheel axles, you could use it alone with a wheel motor to create a 3wd system with a battery pack, also creating an EV only mode albeit not nearly as powerful as using the current conceptual setup. However, if one could devise a system to raise/lower this wheel, it wouldn't create unnecessary drag and could be lowered to help add more power or possibly run the car in certain low-performance situations.

You could also put the 5th wheel into a reverse mode and use it to regeneratively brake and recharge the battery pack, like an enhanced IMA system. Just an idea.

-Phil

 

[clett]

Any individual cell in an array has an impact on the whole. For longevity there is a balance. The 568 cell array will be a tough balance to maintain.

This is true, but with appropriate management it can be achieved. AC propulsion were the ones to pioneer this approach with their T-zero (0-60 in 3.6s, 300 mile range using LiIon). It uses 6,800 individual 18650 cells in series/parallel.

All of the proven EV conversion on the link I provided are of the 12v lead acid type. I can't imagine its simply because they "like" the lead acid batteries better. :wink:

The conversions shown on that website are quite old. People chose lead acid in the "old days" because it really was a no brainer back then - LiIon was just too expensive. However in the last two or three years, people have been moving towards lithium, as it can work out even cheaper than lead acid (and one sixth the weight) - if a little more complicated. A lot of people are keen on Thundersky LiIon, because you can buy big LiIon cells and don't have to fuss around with all the business of connecting lots of small cells together. That's what the 100 mile range solar van uses, and you can see a nice comparison of these and various other battery chemistry costs on the vendors homepage here.

Recently they've had to put their prices up however, as a result of excess demand, so 18650 is now the cheapest way to store electrical energy (cheaper, in some cases, than lead acid). All we need now is some enterprising company (ACP maybe?) to come up with a mass-market 18650 charge manager - then that would really open up LiIon to the EV amateur.

 

[Yves M.]

When I searched for a wheel motor, all I found was for a scooter. Any one has seen a wheel motor for a car, for sale. It needs to be an about 20hp motor or 2 x 10 hp motors. There are wheel motors in cars but are they sold to the public.

 

[b1shmu63]

Running the Insight in EV mode requires that the ICE continue to run if the IMA system is to be used.. How much will this influence the effective "mileage" of the system. To determine this empirically we need to know the RPM of the ICE at cruising speed in 5th gear. (Approximately 2,300 RPM). First run the Insight dry, then add a measured amount of fuel, perhaps half a gallon. Running the Insight in neutral at the cruise RPM, determine how long it will run. Multiply the time by the cruising speed to determine the ultimate possible mileage for the Insight when driven electrically.

Running the ICE while in EV mode is not a total loss of energy as it will provide power for the 12 volt system. It will also generate enough heat to prevent the driver from freezing in the winter, and power the AC in the summer. This will help to stabilize the battery temperature as well, increasing the electrical efficiency.

 

[Foxpaw]

I don't understand - why does the ICE have to run to use the IMA system. Certainately the crankshaft has to rotate, but I don't see any reason why it couldn't be "run" in fuel cut mode.

 

[Yves M.]

In fuel cut mode, it is OK if the engine does not turn. But if it turns, all the energy necessary to turn the crankshaft, pistons, camshaft, valves, oil pump and wear on the parts is not good.

I go with Kip, an electrically assisted IMA assist car. I could be called Assist2 Could it do more than 150 MPG + the electric charging.

Where can you get two 10HP wheel motors.