Drive battery degradation . Houston, do we have a problem?

[Trex]

Ok to stop another thread from going off track and for easier searching I will start this topic.

In this topic http://www.myoutlanderphev.com/forum/viewtopic.php?f=10&t=2935 about a drive battery diagnostic I had done it has come up that anko, one of our Dutch Phev owners, is showing just over 20% deterioration in over 3 years. Remember they had access to the Phev from Oct 2013, just over 6 months or so, before the rest of us mere mortals. :lol: But remember the Japanese have the PHEV for nearly 4 years and what deterioration are they seeing? I have seen over 10% on mine (have not checked lately, and probably shouldn't, but will not be surprised to see 12 to 15%) in over 2 1/2 years (April 2014).

Does not sound good? Mitsubishi have given us crap drive batteries. Holy Hell Batman! . Mitsubishi expected less than 20% in 5 years. I am sure everyone heard that before buying the PHEV. I sure did.

But lets not panic just yet.

First we have to ask ourselves some questions. We knew that the battery was going to degrade did we not? You cannot change the laws of physics said Scotty. They have not invented a perfect battery yet. That's life. I went into this with my eyes wide open. I actually worked out that 40kms range will do me and my family ( around 80% of the stated range of 52kms under ideal conditions that Mitsubishi quoted) to allow for that degradation . My wife who mainly drives the PHEV still on average (when not doing exceptional trips) comes home with excess battery range not used.

Which brings us to another question. Are we seeing a noticeable decrease in EV range?

Now I have posted here on this forum how I have done a test every 6 months (including when I first bought the PHEV) on the same route, at the same time of day, on the same day of the week to check the EV range. Some here thought that was stupid or unnecessary. But I kept doing them (until last year because I have been very busy at work so I missed 1 test ) and will do another as soon as I can borrow the PHEV from my sons :lol: who are at a state Futsal competition (indoor soccer) in Sydney.

But so far on my tests ( and again I will double check this soon) myself or my wife have not noticed a decrease in range. What say you jaapv or anko or other long timers? Are you seeing a decrease in EV range?

If not why are we not seeing it?

This is from the sticky I started from top of the technical section called Technical graphs and images from a Pdf file that anko owned and I had to beg him and jaapv to show to you other forum members. :lol: Sorry, probably a bad joke and thanks again from me and hopefully others for letting us have access to it and jaapv for making it a sticky.


This is one of my favourite PHEV graphs. It shows so much info.

So the question was if we are not seeing a reduction in range why not?

Well see that red line at 26%. That is the floor of the discharging of the drive battery for longevity. Except for what I call emergency use. That is well known by a lot (most?) of us.

Mitsubishi could lower that floor to allow for deterioration. That would be a big call IMHO as it would, I think, speed up the degradation of the drive battery. Is anyone seeing a lowering of the discharge floor?

Or is the information from the PHEV, which anko's decoding for EVBatmon and my battery diagnostic from the dealer (from the MUTIII) rely on, being too pessimistic?

As time goes by we will see but it still too early to panic about it. I know I will not.

But I will ask these question again. Is anyone seeing a decrease in EV range and, if yes, have you talked to your dealer about it?

Regards Trex.

ps Another thing to think about is use? anko does a lot of towing from memory. Is that affecting his battery deterioration more than others? The heat in Australia could also be helping to kill my battery. I know the battery has AC but sometimes it just sits out there in the middle of the day just cooking. :roll: Should probably remind the wife, again, to leave it Ready mode at her work so the AC runs to keep the drive battery cool. I mostly tell (or is it ask? :? ) her not to take it on the stinking hot days but what can I do? It is her car she will tell you. :lol:

So many questions. :lol:

 

[Trex]

I should state here I am joking when I complain on here about my wife and kids always borrowing the PHEV from me.

But I think everyone knows that.

We all love our family and want them to drive the safest car we own. I do anyway.

I always feel better when they take the PHEV. Especially on the trips away.

Regards Trex.

 

[anko]

anko does a lot of towing from memory. Is that affecting his battery deterioration more than others?

Yes, he does. And yes, it may. But we do not write stuff like this on an open forum where the enemy could be listening in .... :lol: :lol:

I share your thoughts about battery Ah deterioration versus EV range deterioration. Currently, I don't get anything more than 21 or 22 miles per charge, where earlier I would easily get up to 50% more. Do I blame the battery? Well, for most part, I blame the weather and my winter tires. Winters have always been much worse than summers.

As I have not done the structural tests you have done, I couldn't tell if this winter was any worse than the winters before. It feels like it, but it could also be my worries playing up. What I have found out is this: thinking to much about it has deteriorated my memory. ;-)

I have also thought about that 'reducing the buffer to compensate for deterioration' which is a known strategy for some car manufacturers. IIRC, at least one plug in model has a 16 kWh battery but is sold as having 12 kWh battery, allowing for 25% loss without the owner ever noticing...

Bottom line: yes, Ah seems to have dropped much more than EV range has. But .... "kWh received during a full charge" has also dropped significantly. I would guess up to 15% at least. If that does not translate in reduced range, it would mean the car (or me) has become more efficient. I don't buy that ....

 

[HHL]

I think the simplest way to get an idea is to just measure what goes in when it has been run down to --- range.
Can easily be done with the MMCS by looking at the charge cost (set it to 1.00 to get a direct kWh figure)
The highest I have seen on mine is 9.7, now it is usually around 9. Assuming the car discharged to say 30%, which is 3.6kWh, adding 9 produces 12.6kWh total capacity when full(ignoring losses in the charger).
I have noticed however, that EVBATMON reports less than 30% capacity when there is no bars showing on the indicator, usually somewhere between 25 and 30.
I did a rough range test a few weeks ago, and I drove 48.5km before the engine started (suburban traffic, not using the "insane mode"), so really quite happy with that. In my case if the range halved it would still be perfectly usable, the biggest worry would be just 1 cell failing, that would be a show stopper.....
The best way to monitor this without bothering your dealer is EVBATMON as it shows individual cell voltages.

 

[elm70]

I think the simplest way to get an idea is to just measure what goes in when it has been run down to --- range.
Can easily be done with the MMCS by looking at the charge cost (set it to 1.00 to get a direct kWh figure)
The highest I have seen on mine is 9.7, now it is usually around 9. Assuming the car discharged to say 30%, which is 3.6kWh, adding 9 produces 12.6kWh total capacity when full(ignoring losses in the charger).
I have noticed however, that EVBATMON reports less than 30% capacity when there is no bars showing on the indicator, usually somewhere between 25 and 30.
I did a rough range test a few weeks ago, and I drove 48.5km before the engine started (suburban traffic, not using the "insane mode"), so really quite happy with that. In my case if the range halved it would still be perfectly usable, the biggest worry would be just 1 cell failing, that would be a show stopper.....
The best way to monitor this without bothering your dealer is EVBATMON as it shows individual cell voltages.

I don't have EvBatMon yet .... so I'm also using the MMCS for read this information

I started with setting 1.00 .. but the graph was wrong on the MMCS ... so I move to 0.10 now .. for have a working graph

Anyhow ... I think the highest value I have seen on my old PHEV (3y & 120k km, took 2nd hand few months ago) has been around 10kwh charge, but this did also include a 10min defrost happening while charging.

Unfortunately I don't get much consistent data on MMCS since I'm very seldom fully discharge the battery

My car at first was reporting 35km as best range (it was +15deg at the time) ... now that is winter ... I have seen up to 39km range (with +2 temperature) .. I guess previous owner was driving differently since he had also a broken charge, so he clearly did not care of burning fuel) ... anyhow ... for know how much range and battery status .. I guess I would need to wait warmer days and my ODB2 with EvBatMon

But ... I think my PHEV has around 15% to 20% battery degradation ... my daily usage is around 25km ... so I hope this can be achieved also in the next 3/5 years to come... else ... it will be time to think about "patching" the battery pack.

By the time ... possibly we have some solution on the market .. with cheaper Lithium cells

 

[ian4x4]

I always thought that the car makers built in a reserve of used battery capacity which allowed them to manage the apparent capacity loss over the planned lifetime of the car, as in the quote below:

The size of the battery packs greatly influences the price of new electric cars and plug-in hybrids. The range automakers expect to get per kilowatt-hour varies because of differences in vehicle weight, expectations about driving patterns, and capacity kept in reserve to hedge against battery deterioration.

https://s3.amazonaws.com/files.technologyreview.com/p/pub/legacy/jan11_feature_electric_cars_p61.pdf

 

[HHL]

My car at first was reporting 35km as best range (it was +15deg at the time) ... now that is winter ... I have seen up to 39km range (with +2 temperature) .. I guess previous owner was driving differently since he had also a broken charge, so he clearly did not care of burning fuel) ... anyhow ... for know how much range and battery status .. I guess I would need to wait warmer days and my ODB2 with EvBatMon

But ... I think my PHEV has around 15% to 20% battery degradation ... my daily usage is around 25km ... so I hope this can be achieved also in the next 3/5 years to come... else ... it will be time to think about "patching" the battery pack.

By the time ... possibly we have some solution on the market .. with cheaper Lithium cells

The range displayed means little as far as battery condition is concerned. It varies a lot depending on how the last few km were driven before charging. I have had mine as high as 70km!, usually it is between 40 and 50, it drops 10 as soon as the aircon is turned on.

 

[anko]

The range displayed means little as far as battery condition is concerned. It varies a lot depending on how the last few km were driven before charging. I have had mine as high as 70km!, usually it is between 40 and 50, it drops 10 as soon as the aircon is turned on.

Or it depends on both ...

 

[Trex]

............enemy could be listening in .... :lol: :lol:

What enemy? Oh, you mean ............ ? Nah, they are friends not our enemy. :lol: :lol:

......... thinking to much about it has deteriorated my memory. ;-)

Yep, sometimes thinking too much about this stuff can do that. And I am sure you have bigger fish to fry.

............ it would mean the car (or me) has become more efficient. I don't buy that ....

You could be starting to slow down in your old age.

Or the mighty PHEV could be just starting to loosen up.

 

[Trex]

I think the simplest way to get an idea is to just measure what goes in when it has been run down to --- range.
Can easily be done with the MMCS by looking at the charge cost (set it to 1.00 to get a direct kWh figure)
The highest I have seen on mine is 9.7, now it is usually around 9. Assuming the car discharged to say 30%, which is 3.6kWh, adding 9 produces 12.6kWh total capacity when full(ignoring losses in the charger).
I have noticed however, that EVBATMON reports less than 30% capacity when there is no bars showing on the indicator, usually somewhere between 25 and 30.
I did a rough range test a few weeks ago, and I drove 48.5km before the engine started (suburban traffic, not using the "insane mode"), so really quite happy with that. In my case if the range halved it would still be perfectly usable, the biggest worry would be just 1 cell failing, that would be a show stopper.....
The best way to monitor this without bothering your dealer is EVBATMON as it shows individual cell voltages.

Yep I did that thing with the MMCS when first got it. Have not checked it for awhile. Will have to check it again. Thanks for reminding me about it.

But I love doing my 6 monthly checks because it is a good excuse to borrow the PHEV and actually get to drive the bloody thing. :lol:

 

[Trex]

By the time ... possibly we have some solution on the market .. with cheaper Lithium cells

Yes, still early days. Mitsubishi or others will have a solution.

We should not worry ourselves about it just yet.

 

[Trex]

I always thought that the car makers built in a reserve of used battery capacity which allowed them to manage the apparent capacity loss over the planned lifetime of the car, as in the quote below:

The size of the battery packs greatly influences the price of new electric cars and plug-in hybrids. The range automakers expect to get per kilowatt-hour varies because of differences in vehicle weight, expectations about driving patterns, and capacity kept in reserve to hedge against battery deterioration.

https://s3.amazonaws.com/files.technologyreview.com/p/pub/legacy/jan11_feature_electric_cars_p61.pdf

Yes there is definitely 2 ways of looking at that reserve that is just sitting there, I think.

Lets try to look at it from a Mitsubishi engineer's perspective.

He know that not discharging the drive battery too deep helps longevity. But it will still degrade over time.

Does he say " Stuff it, I will use the reserve and it will be more usable to the customer at the moment and we are using that reserve already for special occasions" or "No, it will just increase the degradation into the future"?

By talking with the battery manufacturer's engineers and chemists they could probably come up with a good answer. As I am sure they will or have already.

Or they could just toss a coin I suppose. :lol:

Actually the more I think about it, I am looking forward to knowing the answer to that predicament.

Regards Trex.

 

[HHL]

I always thought that the car makers built in a reserve of used battery capacity which allowed them to manage the apparent capacity loss over the planned lifetime of the car, as in the quote below:

The size of the battery packs greatly influences the price of new electric cars and plug-in hybrids. The range automakers expect to get per kilowatt-hour varies because of differences in vehicle weight, expectations about driving patterns, and capacity kept in reserve to hedge against battery deterioration.

https://s3.amazonaws.com/files.technologyreview.com/p/pub/legacy/jan11_feature_electric_cars_p61.pdf

Yes there is definitely 2 ways of looking at that reserve that is just sitting there, I think.

Lets try to look at it from a Mitsubishi engineer's perspective.

He know that not discharging the drive battery too deep helps longevity. But it will still degrade over time.

Does he say " Stuff it, I will use the reserve and it will be more usable to the customer at the moment and we are using that reserve already for special occasions" or "No, it will just increase the degradation into the future"?

By talking with the battery manufacturer's engineers and chemists they could probably come up with a good answer. As I am sure they will or have already.

Or they could just toss a coin I suppose. :lol:

or just Charge ahead :mrgreen:

 

[Trex]

I always thought that the car makers built in a reserve of used battery capacity which allowed them to manage the apparent capacity loss over the planned lifetime of the car, as in the quote below:

The size of the battery packs greatly influences the price of new electric cars and plug-in hybrids. The range automakers expect to get per kilowatt-hour varies because of differences in vehicle weight, expectations about driving patterns, and capacity kept in reserve to hedge against battery deterioration.

https://s3.amazonaws.com/files.technologyreview.com/p/pub/legacy/jan11_feature_electric_cars_p61.pdf

Yes there is definitely 2 ways of looking at that reserve that is just sitting there, I think.

Lets try to look at it from a Mitsubishi engineer's perspective.

He know that not discharging the drive battery too deep helps longevity. But it will still degrade over time.

Does he say " Stuff it, I will use the reserve and it will be more usable to the customer at the moment and we are using that reserve already for special occasions" or "No, it will just increase the degradation into the future"?

By talking with the battery manufacturer's engineers and chemists they could probably come up with a good answer. As I am sure they will or have already.

Or they could just toss a coin I suppose. :lol:

or just Charge ahead :mrgreen:

Perfect :lol: :lol:

 

[Trex]

As I said in my the first post

But so far on my tests ( and again I will double check this soon) myself or my wife have not noticed a decrease in range.

I did another range test and I DID get a decrease. See http://www.myoutlanderphev.com/forum/viewtopic.php?f=10&t=2962
I also asked in the first post:

Is anyone seeing a lowering of the discharge floor?

Well the battery SOC (dash) from EVBatmon was 30.5 so I think the answer is no on my PHEV.

Another from the first post:

Or is the information from the PHEV, which anko's decoding for EVBatmon and my battery diagnostic from the dealer (from the MUTIII) rely on, being too pessimistic?

Ok I think the answer to that is yes.

From my tests I have roughly a 8% reduction in range but the PHEV says, through EVBatmon, I have a roughly 14% reduction in degradation of the battery.

Thoughts about this anyone?

 

[Grigou]

It's easy to measure the kWh in the MMCS for a full charge.
You can compare it with the kWh for a full charge when the car was new (about 9.5 kWh).

I'm afraid that you will find about 8.2 kWh (9.5 minus 14%) ...

 

[zzcoopej]

From my tests I have roughly a 8% reduction in range but the PHEV says, through EVBatmon, I have a roughly 14% reduction in degradation of the battery.
Thoughts about this anyone?

The biggest degradation in the battery happens when it is new, so it is impossible to get a battery from the factory to the customer without some degradation (although this may be partly hidden within the BMU's calculations). This is the same with all PHEV (and EV for that matter). So the initial 6% "missing" drop happened when your PHEV was on the boat, on the dock and sitting at the dealership.

The highest capacity PHEV we have recorded in the EvBatMon database is 39.2Ah (PMC = 98%, ie 2% degradation) @ 5985 km. I happen to have previously corresponded with the Spanish owner who said "I Bought on 24th July 2015, new. I don´t know when was built but I know that was imported to Spain on 11th June 2015.". This PHEV seems to be extra-lucky!

The datapoint we have with the least number of km was from a PHEV in Norway of 37.6Ah (PMC = 94%, ie 6% degradation like you) at only 253 km.

 

[Trex]

From my tests I have roughly a 8% reduction in range but the PHEV says, through EVBatmon, I have a roughly 14% reduction in degradation of the battery.
Thoughts about this anyone?

The biggest degradation in the battery happens when it is new, so it is impossible to get a battery from the factory to the customer without some degradation (although this may be partly hidden within the BMU's calculations). This is the same with all PHEV (and EV for that matter). So the initial 6% "missing" drop happened when your PHEV was on the boat, on the dock and sitting at the dealership.

The highest capacity PHEV we have recorded in the EvBatMon database is 39.2Ah (PMC = 98%, ie 2% degradation) @ 5985 km. I happen to have previously corresponded with the Spanish owner who said "I Bought on 24th July 2015, new. I don´t know when was built but I know that was imported to Spain on 11th June 2015.". This PHEV seems to be extra-lucky!

The datapoint we have with the least number of km was from a PHEV in Norway of 37.6Ah (PMC = 94%, ie 6% degradation like you) at only 253 km.

Ok that is a very good point.

But we do not know what my initial degradation (bought April 2014) was so we are speculating here are we not?

Ok I would like to ask what is the average of degradation with new PHEVs once in the owner's hands and they have EVbatmon ie they are very new to the owner?

What I am trying to say is my 6% average?

 

[zzcoopej]

Lets see if I am getting this right . You are finding on average a 6% degradation of the battery on new PHEVs (before we own them) when you say "ie 6% degradation like you?

No, we really don't have enough early km values to draw that conclusion. We only have 2 PHEV with readings <1000km, and 7 with readings <5000km.
We havn't had any new PHEV come into the country in ages to enable a "best case" reading. However I have contact with someone nearby who has ordered an Australian MY17 PHEV due for delivery in March. I plan to get a very early reading from their PHEV as well as confirm EvBatMon compatibility with the MY17.

 

[Trex]

Lets see if I am getting this right . You are finding on average a 6% degradation of the battery on new PHEVs (before we own them) when you say "ie 6% degradation like you?

No, we really don't have enough early km values to draw that conclusion. We only have 2 PHEV with readings <1000km, and 7 with readings <5000km.
We havn't had any new PHEV come into the country in ages to enable a "best case" reading. However I have contact with someone nearby who has ordered an Australian MY17 PHEV due for delivery in March. I plan to get a very early reading from their PHEV as well as confirm EvBatMon compatibility with the MY17.

Ok thanks. I edited my question because I know you are using my 14% battery degradation - my 8% reduction in range to come up "6% like you"

But you knew what I meant.

So no best guesses? :lol: