Drive battery degradation and replacement.

[jaapv]

Pressing "charge" shouldn't make a difference either.

 

[anko]

That cannot have anything to do with it. As long as the battery can reach an SOC of over 30% full power will be full power.

I wish this was true, Jaap. Mine is restricted to about 50 kW even when full. Makes it very hard to drive pure ev mode even during very short trips. To me this is more a problem than the reduced range itself.

 

[jaapv]

Bummer

 

[Trex]

Pressing "charge" shouldn't make a difference either.

Again I am not so sure jaapv. If Mitsi are going to "throttle" the drive battery to reduce degradation they should let the petrol motor take up the slack IMO.

Better than being stuck on incline (boat ramp) not being able move (without assistance from others).

 

[Trex]

I wish this was true, Jaap. Mine is restricted to about 50 kW even when full. Makes it very hard to drive pure ev mode even during very short trips. To me this is more a problem than the reduced range itself.

So anko have you noticed a problem with pulling a trailer up an incline from a dead stop that you had no trouble with before or do you not tow any more because of your drive battery degradation?

 

[anko]

I wish this was true, Jaap. Mine is restricted to about 50 kW even when full. Makes it very hard to drive pure ev mode even during very short trips. To me this is more a problem than the reduced range itself.

So anko have you noticed a problem with pulling a trailer up an incline from a dead stop that you had no trouble with before or do you not tow any more because of your drive battery degradation?

No issue towing (as I always use charge mode). I think max power is still there but the car tries to avoid it.

 

[windymiller]

We ahve been charting battery SOH since new on 3 x 4Works first registered in April 2017. The first is due to hit the UK warranty level next year at 33,000 miles. Another one, which does less running, is due to hit the UK warranty level at 13,000 miles! :shock:

I have been corresponding with the dealer since the degradation level first became apparant, and they simply don't want to know. They say they have send log extracts off to Mitubishi and all is good. But yet, after 20,000 miles, the battery SOH is more than halfway to the warranty level of 70%, and the graphs we have been plotting since new, show no sign of levelling off. Just a steady downwards slope of SOH vs miles.

We are already starting to make noises (involving legal terms) on the warranty claims that will be coming next year. Sounds harsh, but to date, Mitsubishi and their dealer have done nothing about the warranty issues that have existed since the day they were brand new. Even at the 1 year service, they ignored all the issues, depsite being advised of them 3 months before the service. So I expect, that without starting now, and bringing some legal clout along, that 2 years after the batteries drop below 70%, Mitsubishi will still be procrastinating.

If I can figure out how to paste a JPG of our battery charts here, I will.

 

[Trex]

So anko have you noticed a problem with pulling a trailer up an incline from a dead stop that you had no trouble with before or do you not tow any more because of your drive battery degradation?

No issue towing (as I always use charge mode). I think max power is still there but the car tries to avoid it.

Thanks anko. I better go down to the boat ramp and check this out for myself. The son might just not have been pushing the accelerator hard enough as he did not know the car tries to "avoid" using max power.

 

[Trex]

But yet, after 20,000 miles, the battery SOH is more than halfway to the warranty level of 70%, and the graphs we have been plotting since new, show no sign of levelling off. Just a steady downwards slope of SOH vs miles.

We are already starting to make noises (involving legal terms) on the warranty claims that will be coming next year. Sounds harsh, but to date, Mitsubishi and their dealer have done nothing about the warranty issues that have existed since the day they were brand new.

So your degradation showing with lets just say EVbatmon or similar is approx 15% if I am not mistaken and you are are already threatening ("making noises") Mitsi. Sounds more than a "bit harsh" IMO at this stage. You should and will, I think, have to get your BMU recalibrated long before that.

As for your other complaints about "warranty issues" I do not know how it is where you live but here Mitsubishi do NOT own the dealerships. I suggest you try another dealer because from my experience some are definitely better than others. And yes I know from experience that it can be a hassle having to drive elsewhere.

 

[windymiller]

18% loss after 20,000 miles actually. But its the unrelenting downwards slope on the graphs since new, and the best fit line projection on the Excel graphs that show when the warranty level will be reached thats of concern. One of the vehicles is consistently showing 1.86% loss of battery capacity per 1000 miles driven, and that concerns us. Unless something changes about the slope of the degradation line, then we know fairly accurately when the warranty level will be reached.

The dealer has forwarded an email that they say is from Mitsubishi (hard to tell as they have removed the "From" address) which advises to;

[*]Always run the battery down to "empty" before recharging
[*]Always charge the battery fully to 100%
[*]Never charge the battery if its not already empty
[*]Never partially charge the battery to less than 100%

That was supposed to make a difference to the rate of battery degradation. But it hasn't. What it has done though is make a huge dent in fuel efficiency. You get home with 25% battery, but aren't "allowed" to recharge. So you set off the next day with a nearly empty battery, get a short distance, then the engine has to run.

That Mitsubishi (allegedly) are making recommendations through their dealer to try and reduce the rate of degradation, suggests to us that they acknowledge that this level of degradation is unacceptable

I have noted may posts on BMU re-calibration, but note that it is no magic cure that re-instates all that lost capacity. Perhaps adds a few % back in on the stated SOH for a short time. And this was not something that the dealer did, or even offered at the service just a - "we have taken logs and sent them to Mitsubishi who say that everything is just fine".

 

[windymiller]

Aha, finally figured out how to upload the graphs.

Below shows the plot of 3 x 2017MY 4Work commercials since new in April 2017. Thicker lines is Excel joining together the datapoints, thinner lines is Excel's "best fit", along with projection into the future.

View attachment PHEV Battery levels - Dec 18.jpg

We've been hopeful that the lines would start to level off a bit, but not much sign of it as yet.

 

[Trex]

18% loss after 20,000 miles actually. But its the unrelenting downwards slope on the graphs since new, and the best fit line projection on the Excel graphs that show when the warranty level will be reached thats of concern. One of the vehicles is consistently showing 1.86% loss of battery capacity per 1000 miles driven, and that concerns us.

Concerns us? Now I think you are using a OBD-II device and an app. Yes. Now if you did NOT have those items would you even have noticed the degradation you supposedly have? I mean, have you actually noticed a decrease in range when EV driving.

I will provide just a little bit of history here. Now when I and quite a few others here on this forum first started with the PHEV there was no EVbatmon and such. The only way we could see the State Of Health of the drive battery was to get a report off our dealers which some including myself did.

Well it all changed when anko (yes the same anko you still see here floating around sometimes) decoded the Canbus. Now we have multiple apps to show our SOH of the drive battery and other things.

So what I am trying to say here most of us did not know the SOH before the apps and we were not concerned or worried.

So I will ask the question again. Would you even notice the degradation you supposedly have without the app ie have you actually noticed a decrease in range when EV driving?

To be continued........

 

[Trex]

Now as a follow on from my post above notice I said degradation you supposedly have.

Well we are pretty sure that the BMU is guessing the SOH of the drive battery. As some of us know from our dealing with other batteries, capacity cannot be determined without emptying and then measuring the charge put back into battery (or vice versa ie filling then measuring while you empty a battery) to get the real capacity or SOH. But the PHEV never normally empties the drive battery so Mitsi have provided a neat way to do this (BMU recalibration) using their MUT_III. BUT I have found some dealers not up to speed on this and other things about the PHEV.

That is why I said go see another dealer and I have had to. Was it a hassle? Yes.

I have noted may posts on BMU re-calibration, but note that it is no magic cure that re-instates all that lost capacity. Perhaps adds a few % back in on the stated SOH for a short time.

Now about the BMU recalibration. Yes I have seen some only getting a "few % back" ( I got approx 4%) for a short time. But this is what I have read elsewhere on youtube:

"Had the 2018 phev since Feb. After 20.000 km and battery capacity down to 93%according to watchdog, had car inspection and they suggested battery reprogramming, and they did a dbcam procedure. Since then battery capacity upto and remains at 98,5% and have driven 1000 km. My garage(Germany) doesn't understand all these problems, so the most important thing when buying a phev, which I love and am very happy with it.,is the 3xperience and quality of expertise at your garage. The extra education of the mechanics is expensive so my garage tells me."

Now it would appear that this person had a good result with a BMU recalibration or DBCAM as stated here. You may as well. But you will not know until you do it and Mitsi will I am pretty sure require it for warranty claims.





 

[HHL]

I think there are mainly two scenarios where the BMU will go out of calibration.

1. If there car is mostly driven in hybrid mode and rarely, if ever charged from a normal AC supply.
2. Where the car is mainly charged with DC.

This is where there will rarely or never be any cell balancing and the BMU can not keep an accurate estimate of capacity.

I suspect the cell balancing that can be done by the dealers is a work-around specifically for this situation. The DBCAM procedure is a bit different and its purpose may be to support a warranty claim (or reject it.... more likely).

If the car is always charged fully from the AC supply, the BMU estimate of SOH is probably quite accurate. I suspect that the few people that have acquired a used PHEV and claim that the battery SOH has increased significantly have probably got a car that was not charged a lot by the previous owner.

Similarly, where the BMU has been reset and the car suddenly shows a very good SOH, it soon comes back to reality as the BMU learns the true state.

so, if you are the nervous type... whatever you do don't get an OBD adaptor... just drive it and be happy (or get rid of it)

 

[anko]

Well it all changed when anko (yes the same anko you still see here floating around sometimes) decoded the Canbus. Now we have multiple apps to show our SOH of the drive battery and other things.

Recognition. Thank you

 

[windymiller]

Concerns us? Now I think you are using a OBD-II device and an app. Yes. Now if you did NOT have those items would you even have noticed the degradation you supposedly have? I mean, have you actually noticed a decrease in range when EV driving.

Yes actually. Comapring like for like - weather conditions, temperature, heater off, lights off, wipers off, same route, same cruise control speed setting - the range before engine start up is now reduced from new. Thats actual diustance covered over the road, not the dash "guessometer". Theres a route I ran of 30 miles when nearly new, just to see how far I could squeeze out of it. Cruise control set at 25 mph (the lowest it goes) and it trundled to the end of the 30 mile route, just as the battery gauge hit zero and the engine started. It will now no longer do that, and its lucky to turn in 22 miles of "driving like a complete Granny". OK, so thats extreme testing, but very repeateable. On day to day driving, there is also noticable reduction in the mileage it will cover without resorting to using the engine.

So what I am trying to say here most of us did not know the SOH before the apps and we were not concerned or worried.

Indeed. But doesnt make it right. But that Mitsubishi have issued specific advice, through their dealer, on how to reduce the rate of degradation, makes me wonder how this would be imaginary. Not that Mitsubishi's advice has had much effect on battery degradation - only on pushing the fuel consumption through the roof.

So I will ask the question again. Would you even notice the degradation you supposedly have without the app ie have you actually noticed a decrease in range when EV driving?

And I will answer again, yes. I'll have another go at the "granny run" shortly, and let you know exactly how many miles it manages before the engine starts.

 

[windymiller]

I think there are mainly two scenarios where the BMU will go out of calibration.

1. If there car is mostly driven in hybrid mode and rarely, if ever charged from a normal AC supply.
2. Where the car is mainly charged with DC.

Interestingly, our vehicles are the near opposite of the above. They are only ever charged on the standard 10A EVSE's that came with them, and have only ever been charged on DC about twice - The local ferry terminal used to have a DC charger and a card you could borrow to make it work. But then the supplier of the charger changed something, and the ferry companies card no longer works. So ours have never had any more DC charging than once or twice a year or more ago.

 

[Trex]

If the car is always charged fully from the AC supply, the BMU estimate of SOH is probably quite accurate.

I am not sure about this statement HHL. Now from the person on youtube I posted above says:

"Had the 2018 phev since Feb. After 20.000 km and battery capacity down to 93%according to watchdog, had car inspection and they suggested battery reprogramming, and they did a dbcam procedure. Since then battery capacity upto and remains at 98,5% and have driven 1000 km. My garage(Germany) doesn't understand all these problems, so the most important thing when buying a phev, which I love and am very happy with it.,is the 3xperience and quality of expertise at your garage. The extra education of the mechanics is expensive so my garage tells me."

Now we cannot tell from this if the person used DC charging but reading what he said made me go and check my new April 2018 PHEV and saw that the SOH was 91.84% with only 12,823 kms using EVbatmon. So according to the BMU I have lost approx 8% in approx 9 months with no DC charging and we have been babying the new PHEV's drive battery far more than my oldest PHEV.

Speaking of which ie my oldest PHEV you asked me back in the old Evbatmon thread I started:

Same here... works a treat.

Use an old Nextbook to run it. Very impressive....

My battery % is 91.4% (car built date is Mar 2014, 11,000km)

Care to share your info?

Sure.

Battery condition 90%.

Car built Feb 2014(bought April 2014), 31,415kms

Now this was posted Sun Dec 27, 2015 so nearly 2 years after it was built my oldest PHEV that we did not baby is approx the same as my new PHEV that we do. :roll:

Do I think my new PHEV is degraded this bad for real? No I do not. I think the BMU is being very pessimistic on the new PHEVs as some around here have noticed including the person I quoted above.

Will I bother to get my BMU recalibrated at this stage? Not sure. I may wait to see because it is not effecting the range we need while EVing but I would love to know for sure like the person I quoted above just to satisfy my curiosity.

 

[Trex]

Well it all changed when anko (yes the same anko you still see here floating around sometimes) decoded the Canbus. Now we have multiple apps to show our SOH of the drive battery and other things.

Recognition. Thank you

:lol: That would my pleasure anko. You did good work. Though sometimes I curse you like when I checked my new PHEV's SOH. :lol:

 

[Trex]

So I will ask the question again. Would you even notice the degradation you supposedly have without the app ie have you actually noticed a decrease in range when EV driving?

And I will answer again, yes. I'll have another go at the "granny run" shortly, and let you know exactly how many miles it manages before the engine starts.

:lol: :lol: Just wanted to make sure you saw that question windymiller.