IMA Battery Crash?
 

Once each day now in two days of commuting I've looked down at a stoplight and seen my SoC with only 2 bars. Neither my driving style or my route has changed, and I was not using the IMA excessively. Both times I've experienced this, the car went through a forced regen cycle and then behaved normally with the battery coming back up to 6-7 bars which is where it usually stays for me.

Is this something I should be worried about? Has anyone else experienced something similar? The only thing different about the car was that I had the first oil change done last weekend, although I don't know how that could effect it.

Re: IMA Battery Crash?
 

It is becoming pretty common for some of us with the higher summer temperatures... Especially when operating the AC on Auto.

How warm has it been at your location?

MSantos

Re: IMA Battery Crash?
 

Both times were on the commute in so temps around 60 or so, and my A/C was not on (displayed as A/C Off so no phantom A/C).

Re: IMA Battery Crash?
 

I wonder if you experienced a battery recalibration either of those times. When these happen, you can watch your indicated SoC quickly drop down to no bars (1 bar at a time). Forced charging then occurs. Maybe you noticed it when the charge was already on the way back up. I've had this happen to me twice. Anyway, just a thought.

Re: IMA Battery Crash?
 

It happens to me frequently right now but I have temps from 110 - 120 which is not what you are facing so I am not sure. In our winters, tempe around 60-70, I did not have that happen ever. I also drive a flat route, may that be part of it?

Re: IMA Battery Crash?
 

I don't know, but it's possible. I've been watching the SoC like a hawk since it happened yesterday morning and haven't seen it since (although I drove the Sub today). Hopefully that is what was causing it, and it's done recalibrating now!

Re: IMA Battery Crash?
 

I had a similar battery crash experience about 1 week ago in my 2007 HCH-II. On that particular day the air temps were over 105 degrees and the AC was running on auto full blast. I got stuck in stop and go traffic on my commute home when it happened. My battery charge indicator plummeted until no bars were visible. I call that a crash.

Once I got moving again (following the traffic tie up) the car felt very underpowered because the IMA was no longer assisting the ICE. Seventyish horsepower ICE is not enough to propel a 2,900ish pound car. But I digress.

My car started to do "forced regeneration" even when at a stop. When at a dead stop the ICE automatically reved up to about 1,500 RPM, and then the green regen bars appeared on the charge indicator. This mechanical process was not pefectly smooth, but it did restore about 1 bar of battery charge within a few minutes.

Since that day, my car has returned to normal operation. But I found the experience somewhat "unerving", and it played on my fears about the reliability of the IMA Hybrid system.

Here is what I learned from research these symptoms online and in the owners manual. Page 69 of the 2007 Civic Hybrid owners manual describe the process of automatically recalibrating the battery guage on a periodic basis. That description is very similar to what I experienced (as described above). The manual states that "This correction of the battery level is normal and does not indicate a problem. If the IMA battery develops a problem or becomes deteriorated, the IMA system indicator will come on. If this happens, have the vehicle checked by your dealer as soon as possible." OK, I guess that means this "battery recalibration" is a normal operating process, and I should not worry about it given that the IMA light in the gauge cluster did not illuminate. Hopefully as the air temps drop back to normal (highs in low 90s), the process will not be repeated.

Has anyone else had this experience, and did it occur more than once? Please share your experience on this forum. Thank you:D

Re: IMA Battery Crash?
 

I've had it happen a couple of times in 16000 miles/1 year of commuting. The first time was heavy-stop-n-go traffic (mostly stopped :( ). Same experience as you had. BTW, the ICE is 90 Hp, plus 20 from the IMA system, for a total of 110 Hp. You're right, though, ICE alone is definitely sluggish.
The other couple of times this recalibration occurred (if that's what this indeed is) seemed to be random. At least to me.

Re: IMA Battery Crash?
 

I noticed this sort of thing recently as well. Recently, I had parked and went into a store. I'm fairly sure I had a few IMA bars left (I've never seen it run to zero while driving), but when I got back into the car and started to drive off, I noticed no IMA bars left. Unfortunately, I've not been able to figure out what I've been doing to trigger this. Weather here has been 90s-105 so maybe that's a factor. The car did not seem to rev up, so I don't think this was the recalibration that was described.


- Frank

Re: IMA Battery Crash?
 

So, does anyone feel that it is harmful to the battery if you leave it with a very low charge (like 1 or 2 bars) overnight. I know the battery is never really at 0, but does it hurt the charging power by leaving it low for 10-12hrs ??

I would drive an extra 5miles or 5minutes to bring up the charge.

just my thought.

Re: IMA Battery Crash?
 

I've been monitoring the IMA battery bars a bit more-- it seems that when I've parked in the sun with temperatures around 100, when I return the the car, my battery bars will plummet after driving just a little while. I went from 3/4's full down to 1-2 bars very quickly after doing some normal (easy surface street) driving. Often, the bars start out around 3 or 4 and drop to 0 or 1 until I've done enough regenerative braking. This is very problematic, since the car generally has not recovered by the time I need to get on the freeway-- the car's acceleration is dangerously poor without the IMA assist.

So my question to everyone is-- is this normal for the technology? Or Honda? Does a Prius have this problem? Is it just a few of us who have defective batteries?

thanks,

- Frank

Re: IMA Battery Crash?
 

Frank, how are you running your A/C, and are you auto-stopping at all on the way to the freeway? I ask because when I've driven in similar conditions, I've found the car uncomfortably willing to auto-stop even as the A/C sucks the battery down much farther than I wish it would. I've never seen 0 bars, but I've seen it go from 5 to 2 under these conditions.

So, I use most of the tricks we see posted around here: get as much hot air out of the car as possible; start with the temp high so the A/C isn't maxed but it's still blowing cool air, and work the temperature down slowly; don't let the car auto-stop until it's cooled down quite a bit. Unless there truly is a problem with the car, these kinds of tactics should keep the battery from flattening, if you're gentle on the throttle.

cheers --
doug

Re: IMA Battery Crash?
 

Frank, same thing happens to me and I am in Phoenix, AZ. I do what the other suggest and I have about 1-2 miles until the freeway and I am usually ok by the time that I get there. I just drive very gingerly until the freeway and usually am at a couple of bars that can get me on the freeway at a decent speed.

Re: IMA Battery Crash?
 

ftlum:

Yes, this behavior is by design and very normal.

This is not a problem. As a matter fact, it is an indicator of the measures that today's hybrid vehicle manufacturers must implement to promote long and safe operation or their NiMH battery packs. The Prius exhibits roughly the same behavior and like, the HCH-II, an altered behavior such as this evident in extreme hot or cold conditions.

Now for the hot summer days, there are those of us who have yet to make a connection between the sensible operation of the AC and the behavior/life of the battery pack.

Again, the key is to use our air conditioning wisely. In other words do not set an aggressive temp at first. Set the Climate control on Auto and set the highest temp you can. Then, as the blower fan slows down you dial in the next lower temp value, and you continue to do so until you feel comfortable. You'll notice that the comfort temp is sometimes higher than what you expected and this is the ideal setting for both you and the IPU.


vincep5:
There is no danger or impact on the life and performance of the battery pack if left on 2 bars of charge overnight. Next morning (or whenever) you start the car its charge level will be restored.

Cheers;

MSantos

Re: IMA Battery Crash?
 

Thanks All.

I've been working on trying to keep the AC down, but it sure gets hot in Sacramento. I'm actually planning on getting my windows tinted in the near future so I don't have to run that AC as much.

It's too bad they don't make a solar panel to recharge the battery while you're parked in the hot sun. I've seen ones that plug into your cigarette lighter to recharge a dead regular battery. Too bad you can't easily route that to the IMA battery.


thanks again,

- Frank

Re: IMA Battery Crash?
 

My wife experienced the dreaded crash on her way home tonight. She was using the A/C at the time, although all three of my experiences have been without A/C. The battery went down to nothing and then she said the accelleration was dangerously slow until the forced regen brought things back to 4 bars of SoC.

So the word recalibration has been thrown out on this thread which I find a little interesting. That word is also used in reference to the iFCD recalibration samba, which is something I notice daily (usually multiple times daily).

I think it's time to take it in to the dealer and see what they have to say.

Re: IMA Battery Crash?
 

I've had the problem quite a few times. Usually my charge level will drop to 0 bars, the car will be sluggish, then it will creep back up to normal charge levels. Recently, however, the crash also stalled the car and lit up the dash with indicator lights. It would not restart immediately, although it did restart after a minute.

This is very concerning to me, because a potential stall on a highway would not be a good thing (I was leaving a parking lot at the time, I'd been parked for 5 minutes). I took it to my dealer, who claimed that it was the first that Honda had heard about the problem. They also said that it was probably b/c the interior temp of the car was too high, but this doesn't jive with the facts b/c the car didn't heat up enough in 5 minutes to put it over 90 degrees or so.

The thing that's really bumming me out is that now the battery never charges much beyond the halfway point, even if I 'manually' recharge it in park.

In short, I'd encourage anyone with the problem to take it into their dealer so that Honda becomes more aware of the problem.

Re: IMA Battery Crash?
 

hm.. that doesn't sound too encouraging..
bit_runner, it may sound like it may be more of a problem than a battery crash if the indicator lights come on.. normally, a battery crash would just lose soc, without stalling the car..
did you try bringing it to another (different) dealer? it really would be concerning if you were on a freeway. how old is the car?

Re: IMA Battery Crash?
 

Well, the stalling/lights-coming-on only happened once. Usually it just looses all or all-but-one of the bars on the charge indicator like others have mentioned. It's always possible that they are unrelated issues, but it's just a heads up to others with similar symptoms that it could lead to the stalling problem... so having a dealer check it out is a good idea. My HCH is a 1 year old '06.

Re: IMA Battery Crash?
 

For what it's worth, ours is also an '06 that is almost exactly one year old...