Serial/Parallel Switch Speed

[Johny451]

Under normal accelerator setting the PHEV switches from series (generator mode) to parallel mode (ICE coupled to front wheels) at about 70 km/h.
This is fine for normal driving - but, I mostly tow with the PHEV.

It has plenty not power but NOT plenty of energy. I drive out of the driveway towing about 1200kg with the PHEV fully charged and switch to CHARGE mode.
After 300km at 95km/h I am sometimes lucky to have any battery bars remaining.

The battery power is mainly consumed up hills and the pitiful generator power that the car produces in parallel mode generally does not replenish the battery.

The worst trip was just completed coming back from Gippsland Lakes to Melbourne (298km) towing a 6 meter boat. I have a feeling there was a 15km/h headwind as well.
(The boats aerodynamics are terrible.)

Often on trips, when faced with many hills, I slow down to just under 70km/h which then allows significant battery charging BUT it must annoy the hell out of cars following me. Like I said - plenty of power but not energy.

What would be really good is a hack/way to increase the series/parallel switch over point to say 85km/h.
Anyone?

Edit: BTW CHARGE or SAVE - makes no difference.

 

[jaapv]

Why would you want to drive with a full battery permanently?

 

[Johny451]

I don't. When towing it DOES NOT stay charged. Each hill at 90-100km/h takes a little out of the battery. At that speed there is little replenishment of the battery charge. After 300km - no battery left.

 

[Kesto]

I don't tow. I may be wrong but my understanding is when tow you always start with Save , it will still consume battery when it needs extra power but with Save on you will store more downhill. Take save off if you are at slow crawling traffic.

 

[MartinPHEV]

That's a little odd Johny. You're right to keep the car in Charge mode if you're towing anything substantial but I'm surprised the traction battery becomes depleted.
However, would you not be better off trying to keep above 70 kph on the hills to make the ICE the primary mover if this is achievable?
Interesting thread, I would like to know the outcome.
I wouldn't bother talking to a dealer. Have you asked Andy near Brisbane what his thoughts are on this? He is remarkably over informed on such things!

 

[Johny451]

SAVE and CHARGE do exactly the same thing when towing and you hit a hill or two. It just can't keep the battery charged.

I only slow to 70km/h when the battery is almost fully depleted.

Happy to contact Andy - how?

 

[Johny451]

One additional point. In REALLY hilly country where you are down to 60-70km/h it's not a problem. The ICE is free to rev as high as it likes to generate lots of elecyricity - series mode.

 

[jaapv]

I don't. When towing it DOES NOT stay charged. Each hill at 90-100km/h takes a little out of the battery. At that speed there is little replenishment of the battery charge. After 300km - no battery left.

Do you mean that the car went into "Turtle" mode? Did you see the dashboard warning for imminent loss of power? Just seeing the range and battery bars go down is not a reliable indication, although I admit that it used to make me nervous in the beginning.
A pity Anko has left. He was our expert on towing long distances.
I find the car will switch to series mode at all speeds, well over 100 kph, when I floor the pedal, but then I rarely tow.

 

[Johny451]

I don't. When towing it DOES NOT stay charged. Each hill at 90-100km/h takes a little out of the battery. At that speed there is little replenishment of the battery charge. After 300km - no battery left.

Do you mean that the car went into "Turtle" mode? Did you see the dashboard warning for imminent loss of power? Just seeing the range and battery bars go down is not a reliable indication, although I admit that it used to make me nervous in the beginning.
A pity Anko has left. He was our expert on towing long distances.

No, not turtle mode, but a previous trip made me aware that once the battery bars are gone, demanding lots of power DOES cause turtle mode.

I find the car will switch to series mode at all speeds, well over 100 kph, when I floor the pedal, but then I rarely tow.

Agreed. But when you demand lots of power like that and it switches to series mode, most of it still comes from the battery.

I'm not really after an expert on towing. I have been towing with the PHEV for a couple of years now and I am pretty aware of the shortcomings. I've just recently started trying to see if anyone has found some workarounds.

 

[jaapv]

If it is in series mode it will deliver 60 kW by the battery and 60 kW by the ICE. It can never bring more than 120 kW to the wheels this way. If it is in parallel mode it can delver 60 kW to the wheels by the battery and max 90 kW to the wheels by the ICE, depending on road speed. The ICE cannot deliver full power at lower revs, obviously, reason it will not switch to series above a certain load/speed combo.
If your bars are gone, there is still about 10 % power reserve in the battery.

However, you will not be running at full power all the time. If there is less demand, on the flat or downhill, or in traffic, the battery will be replenished, if you have engaged charge it will go beyond one bar.
I recognize that the car could have been fitted with a more powerful generator, and possibly ICE, but there is a balance to be struck between ICE power, electric motor power, charging capacity, battery capacity, battery stress, economy, weight/size and price. Just fitting a more powerful ICE would not have helped. This is the compromise Mitsubishi chose.
Actually, there was a slight compromise shift in the newest model.
It is, after all, one of the very few PHEV vehicles capable to tow at all.

I must add, that your case is rather exceptional. In many countries there is an 80 kph speed limit on towing combinations, in Europe continent-wide with a few exceptions to 100 kph.

 

[N6IO]

I know what you mean about the battery draining below zero bars even with "CHARGE" pressed. The car is not very aggressive at charging while there is a load on the engine.

I have found that SAVE works better than CHARGE if you press it early. In charge mode it will charge if it's not too much strain. In save mode it also charges if not too much strain. However once you get 20 or 30% below the point you set for SAVE it gets more aggressive about charging even with some load. I find that in my hilly high speed trips if I press save at 70% it will drop to 40% or so but then it tries harder to keep up with the charging. Give that a try. Note that I mean SOC as reported by the dog, not the percent of charge shown by the bars...

I also recently found that pressing ECO on or off plus save or charge seems to make it go into series hybrid mode more often, but I have not really figured a pattern for it yet. Need more road trips to experiment.

 

[ThudnBlundr]

I'd be interested how you found that the car charges harder in Save than it does in Charge. As far as I'm aware, once the engine is running it charges the same in either mode.

 

[jaapv]

Agree, the charts on this forum bear this out.

 

[Phevy]

I've also seen a steady decline is SoC, but I was able to pull 1250 kg at 105 km/h for 300 km and still have 40% SoC. Maybe it helped that the last 70 km was on an 80 km/h road and my average was therefore more like 60 km/h.
And I guess my pop-up trailer has better aerodynamics than your boat.
But yes, I can see that there is certainly a point where you deplete the battery.
Guess that's the time for a bio-break and a charge for the battery.
Maybe still a use for the CHAdeMO after all.

No plans for trip beyond 300 km yet...

 

[Mitch]

I went many times fully packed and with my caravan (no I'm not Dutch :lol: - sorry jaapv :mrgreen: ) to the Alps and the Dolomites.

Sure uphill, the car can't generate the needed energy and the battery will went down. But on straight roads and for sure on downhill, battery get's refilled.
So for me going in safe/charge was always fine, no issue and even no turtle.