I am a new HCH2 owner and so still "learning" and experimenting with the car. Right now I'm testing the current tank using my regular (pre-hybrid) driving techniques. And something that I noticed right away was that battery charge stays pretty high most of the time in this mode (not using glide / ev glide etc). Without trying I've been regularly seeing full charge.
And I read one some thread that the battery has a limited number of charge cycles. So when using hypermiling techniques ... the battery charge gets used up a lot ... and then charged a lot ...
Does this mean that the battery will die sooner for hypermilers?
Frankly, the HCH-2 is less prone to problems when compared to the previous generation IMA's systems in other Hondas. Now, this is not to say that frequent deep discharges are not possible. In fact, they are, especially if you give in to the extreme Hypermiling techniques that use prolonged usage of EV.
In my opinion, the primary key is to use a set of techniques that you are confortable with, feel safe and especially those that give you the most FE benefit without going through extremes that may compromize the system's ability to properly maintain the battery charge. Now that's a mouthfull.
In my book, maintaining a good state of charge is a fundamental secondary key to not only having good city FE, but also driving in as much comfort as possible. In the past I dreaded ANY regen. Now, I actually try to evoke it especially when travelling at steady state and at engine loads below 50%.
The key thing is avoiding a lot of recals. There is a lot more to hypermiling than pulse and glide, but you have to watch the SoC more. When the battery level starts getting low, it's better to get the charge up avoid P&G during that time.
What I tend to do is ...
.. accelerate to desired speed and then coast if possible
.. once in coast, I'll gently press the pedal to cancel out the regen so as not to lose speed and if I'm on a relatively flat road or going downhill ... i will use EV mode (assist bars light up with iFCD still showing 0 - I am in Canada so its caliberated in litres / 100 kms) to maintain speed or even accelerate slightly.
So at this point I'm basically using my hybrid battery a fair bit. I also tend to do this when I'm in my neighborhood (40 km/hr zone) with no traffic behind me.
When using these techniques ... I normally fluctuate between 4 bars and 7 bars on the SoC display. When it hits 4 ofcourse I hit forced regen.
Without using these techniques ... I have seen that my SoC stays near 7 bars most of the time. It drops to 6 at times but has never hit 4 in the past 7 days.
Am I doing something wrong with regard to the coast / glide / ev techniques? i.e. over exerting my battery?
I would venture to say that if you can keep your SoC from varying alot that well, better yet, stay close to 7 bars often... then you are doing much better than most of the folks I know.
My regular operating range is more like 5-6 bars most of the time. Very rarely do I get to 7 bars, and I definitely work to keep the forced regen from appearing.
Honestly, keeping 7 bars on for a long time is literally impossible for me to do. Now that I think of it, since I had my last oil change done (this last Monday) and especially after the 2 software updates, its been very difficult to stay at 7 bars for any amount of time. hummm....
Yes I do have an 07. And I think you misread ... or maybe I didn't make it clear enough ...
I stay near 7 bars ONLY if I drive "normally" i.e. no glide / ev etc. Since my last fill up which was last thursday, I've gone back to my old driving habits to see what kind of FE I get without changing my driving style. And instantly I noticed that my SoC stays very high. Before last Thursday I had seen a full charge (8 bars) just once (in about 5 weeks of driving the car). And in the last week I have seen 8 bars almost once every day.
If I use glide / EV ... I tend to hit forced regen (4 bars) quite often. Although I have never had a Recal (all bars disappearing).
I also recall that whenever my wife drives it ... the SoC is pretty high afterwards which supports the same theory since she doesn't try to coast / glide / ev.
So far I notice about a 0.5 litres / 100 km difference in FE based on the 2 driving styles. So roughly that translates to about 1000 litres of fuel over the life of the car (200000 kms). Sure thats significant but if while trying to save those 1000 litres of gas ... I end up wearing out my battery faster such that I'd have to worry about having it replaced after the warranty expires ... I'm not sure which option is better
But, I still find it fascinating that your SoC remains high when the car is driven normally. At least higher than what I (or others I know) get when we drive "normally".
Anyway, to echo your observations, in my case the SoC really takes a fast dive whenever EV is used for a measurable amount of time. I don't get a confortable feeling seeing to much of that.
I agree, it is a good question.
Fortunately or not, I've decided to force my own battery mgmt routine and only use EV when the benefits are measurable enough to be worth it. This means that I am more interested in a longer battery life rather than playing the EV "rock star".
Since my commutes are rather predictable, this strategy works very good thus far, but the trick remains "staying off the EV mode" particularly during P&G.
If not aided () the EV mode is too easy to evoke and before we know it we're hitting the 4 bar and forced regen as you noted which means a noticeable swing in SoC.
In the end, I guess it remains a matter of personal preference - To EV or not to EV.
I'm actually interested in seeing what the behavior on my new 07 is going to be when it arrives (being built today). Contrasting the two should be interesting.
In temperate weather my SOC stays pegged at 7 bars pretty much with some dips to 6 bars. Winter weather swings my SOC a lot while in the summer it seems pegged at 5 bars most of the time. After some forced regens at the start of winter I've conditioned myself to avoid EV glide as much as possible such that I'm still doing that today even though it has warmed up. I think the reason why my SOC stays high for the most part is I haven't learned yet how to coast without regen. I anticipate traffic and know how much my car slows down with regen and that's what I do with regard to following distance/light timing. I've noticed with A/C on I usually lose 2-3 bars of regen than with A/C off while coasting.