Hello,

Does anyone know if someone is selling a conversion kit for the Honda Civic Hybrid to make it pluggable? Also, would you have information on why it is hard to convert it to pluggable?

Thanks in advance for your help!

 

i'm not aware of anyone making a pluggable hch. it would not be difficult to convert an hch to pluggable however the effort may not be worth it. the electric motor on the hch is not large enough (20hp max. output) to physically move the car from a stop. nor is it powerful enough to maintain a constant speed, unlike the prius. so, you would have to add additional battery packs to take advantage of the plug-in part but the motor itself wouldn't be sufficient to use all that power. a plug-in might help with accerlaration and hill-climbing and that would positively affect your mpg but would not be worth the thousands of dollars necessary for the conversion.

 

This is a good point. The 20hp max Honda motor probably could only sustain about 10hp efficiently for steady-state cruising. The Prius uses elecrtic motors with max ratings far greater than what can be supplied by the batteries--as its electric CVT operates by varying engine power between mechanical, and elecrtic pathways -- so most of the power going through those motors actually comes directly from the engine itself. This means though that in "all electric" mode, the Prius battery max output is still well below the maximal power in the motor.

However, even 10hp sustained would be enough to run the HCH-II valves-closed "glide" mode at creeping speeds -- where electric mode makes the biggest difference. At speeds greater than that, the engine itself is reasonably efficient anyway.

I think this is a good point that is often overlooked in discussion about plug-in hybrids. I bet having the ability to have moderate assist active for nearly the entire commute, with the engine is running at its dead-on most efficient spot nearly that whole time would be more effective in terms of overall gas savings than running the plug-in pack dry with "EV" mode driving, except for very short trips. Using grid power to offset the most inefficient moments of engine-on time will be the most "bang for your buck".

To do it on a Civic, someone would need to come out with the necessary equipment to manually override the charging/assist algorithms (similar to the MIMA project on the Insight) A plug in pack wouldn't need to be very exotic, as it it would supply gradual assist, or gradual charging. A small set of deep-cycle lead-acid batteries cycled 50% would probably get the job done without too much cost, as they woudln't require special elecrtronics to track state of charge, etc. However, weight would rule out a very high capacity pack.

Also, for drivers who live in very mountainous areas, where the stock pack is too small to be of much benefit, the extra plug-in batteries could be discharged, then re-filled on the way back down.

 

The Honda IMA system can't run by the motor alone.
The motor and the the crank shaft are connected together and the system needs a lot of power to spin the crank shaft by the motor.

Ken@Japan

 

While this is true, the resistance is low enough with the valves sealed at low RPMs to allow brief periods of elecrtic "creeping", even with just the stock battery. At such a slow speed, the extra pumping losses incurred by running the engine at barely above idle would be more wasteful the inefficiency of the elecrtic motor spinning the crankshaft. Also, simply having the motor running much more often, or even continually, in conjunction with the engine would be a big benefit of a plug-in system.

 

this is not quite true as double trinity points out. ima in the hch.ii can and does power the car alone - albeit not often and not a lot. while the motor and the crank shaft are mechanically connected, the motor doesn't need that much additional power to spin the crank shaft by itself. ima shuts the valves and minimizes pumping losses. additionally, the pistons and cylinders walls are specially designed to be low friction. the real problem lies with the size of the motor. a larger motor would allow ima to power the car more often under electric power only. an additional problem would be that the power would need to come from the batteries which would deplete relatively quickly, even with more of them.

 

As someone who lives at the top of a hill, I agree that the existing battery capacity is less than optimal. A larger battery pack would help, but plugging in wouldn't do much good at all.

For the HCH to be useful as a plug-in hybrid, it probably needs to double the electric motor's power and have five times the battery capacity. Then we might get up to 30 miles range of city driving, up to 30 MPH, on battery power alone. If you only drove 30 miles per day, you could charge it overnight and never buy gas.

I wonder if plug-in hybrids will have a problem with the ICE if they seldom use it.

 

In a cold environment, it would be bad to be cold-starting after a long run in elecrtic mode, especially in a situation where peak power is needed. Flogging an engine from a dead cold start to WOT would be a bad thing. So, for a plug-in to be workable, it would still be wise to run the engine (at efficfient points) andimplement systems to maintain engine temp. during down-time better, perhaps implementing an insulated bottle for storing the hot coolant for long stretches of time, as well as an automated sheath to block the radiator when cooling is not needed/desired (this would also provide a slight drag improvement). A coolant-heater system on a timer could also be integrated with the charging mechanism.

True, it wouldn't do much good on the trip down the hill from home, althugh, the standard battery pack, which woudl not be effected by the plug-in power, could still be charged up as normal. My main point was for those who live in an area where they drive up and over a big mountain pass -- they could start with it charged, deplete it, then recharge.

 

I'm confused about this. In my HCH, the assist up a big hill or even on flats when accellerating doesn't have much battery to last. Maybe three or four accelelerations or an uphill assist of a minute or less. How would plugging it in really help that much? With the small amount of HP and battery in this electric system, I just don't see how charging it at home would make any difference, unless all your trips are a mile or less and you charge it every time.

However, if the suggestion held that they came out with a bigger motor and battery so that it had a decent range without turning on the ICE, then it would be useful. Essentially then you'd have a charge-at-home electric car with an ICE backup. Stick a solar panel on the roof and it could double the worker's commute range. Why don't we have those already? Every time I read about the experimental versions they say they can only do 60 mph and get about 100 miles on a charge (and they've been saying that since Carter was in office). Geez, for a lot of commuters and around town driving that's quite enough speed and range. Let's get those cars on the road already, we've been waiting 30 years!

 

zimbop,

I would be happy to have an total electric vehicle that had 100mile/60mph capability. That would cover 99% of my driving needs.