Funny thing is, on warmer days here in Los Angeles, the autostop works RIGHT away, instead of making me wait. I'd wait to see how it faires in the summer time, where it can reach 100+ out here in La Verne....

 

A warm day in LA is quite cool in Houston.

 

I know of one other person in H-Town who has a HCH-II in Metallic Pearl, who happens to work with me. Ouside of him, I saw an Alabaster Silver just the other day. That's about it. Considering how hard it was for me to find this one, I'm surprised I'm not running into more of them.

Jeff

 

Let me put it this way; If I see you I will honk ( er- beep) at you

 

Autostop temperature is based on engine block temperature primarily, as starting and stopping an engine when cold puts a lot more strain on it. It shouldn't be affected by the batteries being too warm. If the batteries get too hot, IMA runs at reduced capacity during regeneration (regeneration is what heats up the cells the most), but still allows some assist (so as not to have a loss of power, whcih could be very bad if it happened unexpectedly when merging onto a freeway or something). This could very rapidly eat away the state of charge though, to the point where auto-stop will not kick in due to low battery SoC, even though the engine is warm enough.

The only time I've had the battery stop charging on me was when I went out on a hot day from my house, which is on top of a huge hill. All the charging on the way down really heated up the battery, to the point where it completely stopped charging even with only about 3/4 SoC indicated. That happened even though I was running Max AC all the way down (even at 100% regen I still have excess momentum, running max AC creates the perfect amount of braking).

For someone in a very hot place, especailly one with any long extended periods of charging, I think a great mod to do would be to fix some kind of computer water cooling system onto the battery. Luckily for me, Southern California doesn't often get hot enough for me to need this, especially not if I get dark rear window tint, and clear heat- and uv-blocking front window tint.

As far as the IMA not working in very cold temperatures, that I believe could be solved by adding some electric heater coils around the batteries. It would need to "waste" some power to create the heat, but that should be more than offset by the improved battery performance.

 

Rysa - I'll be a listenin' fer ya.

Jeff

 

I park in a blacktop parking lot at a power plant when I work days and crack the windows and use a sunshade in the front window. 50,000 miles and no problems....as of now.
I have seen more and more HCH in the past 4 or 5 months, 1st gen I should say thou.kevin

 

Interesting replies. Aside from the demand that I perform statistical tests before posting general observations, I appreciate the responses - especially Double Trinity. I'll start looking for performance issues like those described, but it is hard since we don't have significant hills here - probably won't see battery overheating to such an extent.

Couple of thoughts:
1) The issue with battery performance as described by Metro staff could not be observed by viewing the bars on the HCH, or generally noting that charging or discharging is/is not occuring. What they observed is that the efficiency of the charging/discharging decreased when the battery got hot. At the extreme case, the battery ceased playing a functional role in the system but gas mileage would suffer well before this point.

2) I have not observed any issues with autostop that seem to me to be related to battery temperature.

3) I notice lots of HCHs in Houston! Where are you guys driving? I can say that I have pulled up next to or behind HCH-Is of the same color as mine on different occasions, and plenty of others besides. Ours is the tan/gold color with a KPFT bumper sticker.

4) My original theory on the CVT drive issue has to do with the lack of skewness in the data, I agree the standard deviations are similar. I agree that with a larger dataset the theory would be a lot easier to explore.

5) What I was hoping with both of these questions is that someone with more technical knowledge of the HCH systems might be able to study these questions. (Maybe a Honda engineer is lurking . . .) For example, there might be a battery temperature sensor reporting to the onboard computer - maybe there is a way to get at these data, but then one would need to know what is acceptable. Also, are different battery types sensitive to temperature in different ways? And regarding the CVT, I don't know much about how it works so some thoughts on what aspect of the manufacturing process might present quality control issues might be of value - maybe something that could be observed by a clever mechanic.

John

 

Sorry John - I meant that I haven't seen many HCH-II's in Houston. I've seen quite a few HCH-Is around.

Jeff

 

Ya me too. No 2006 HCH IIs in Houston hardly at all.