Realistic range?

[anko]

is 0.05v so much difference?

Look at the cell voltage graphs. A new and healthy battery would have all cells in the Blue range when battery is fully charged. A partial charge would have cells in the upper green area.

I think that will be impossible, as to my understanding the graph shows voltage of cells related to each other. It is impossible to have all cells 'above average'. The highest cell(s) will always be blue. The lowest cell(s) will always red. Right, Jeremy?

 

[elm70]

is 0.05v so much difference?

It does sounds little .. but it is not.

Consider that 4.10v is 100% charge .. and 3.80v is 30% charge

A difference of 0.05 is 11% in state of charge

Since the real battery capacity should be based on the lowest capacity of the cells is used in series ... with an unbalance of 0.05v .. I would not expect a battery health above 90%

If the PHEV does not manage properly this weak cell, this will get worst rapidly .. since it is exposed to be over discharged

 

[robdickinson]

Ok app is reporting soh is 94%

Here is the cell graph from 'fully charged' this morning. Cell 19 still low


what is image hosting

 

[AndyH]

So now I have some detailed battery info... Looks OK?

Rob - what's the 2nd app you're using?

You might want to plug the car a couple of times so it can fully charge and balance the cells. It might take a couple of charges, depending on how well the balancing system works in the car. See if that brings all of the voltages back in line.

 

[robdickinson]

2nd app is evbatmon

Charged 4-5 times now since owning

 

[PHEV07]

So now I have some detailed battery info... Looks OK?

Rob - what's the 2nd app you're using?

You might want to plug the car a couple of times so it can fully charge and balance the cells. It might take a couple of charges, depending on how well the balancing system works in the car. See if that brings all of the voltages back in line.

Noticed that the same Cells are low compared to higher valued ones.

Wondering if the Auto Levlling is not working properly or if the lowerer cells are not charging up to max anymore.

I am still looking around to find out which of the 8 Cells are connected to which of the 10 Modules. Would help in trying to detrmine why the same Cells much lower than others.

 

[AndyH]

2nd app is evbatmon

Charged 4-5 times now since owning

Thanks. When did you last plug the car in and leave it overnight, or at least until you saw the 'charging complete' message on the dash?

 

[robdickinson]

2nd app is evbatmon

Charged 4-5 times now since owning

Thanks. When did you last plug the car in and leave it overnight, or at least until you saw the 'charging complete' message on the dash?

Overnight last night, unplugged 2 hours ago before that last cell graph

 

[anko]

2nd app is evbatmon

Same data. Different representation ;-)

 

[AndyH]

What do you think, experts - is Rob a candidate for cell smoothing?

http://www.myoutlanderphev.com/forum/viewtopic.php?f=10&t=3102

Seems the pack is out of balance and could use a bit of help.

 

[PHEV07]

What do you think, experts - is Rob a candidate for cell smoothing?

http://www.myoutlanderphev.com/forum/viewtopic.php?f=10&t=3102

Seems the pack is out of balance and could use a bit of help.

I am by no means an Expert but it sure looks like some Cell Smoothing would be required here. If that does not equalize the Cell Voltages then a Battery replacement may have to be looked into.

 

[anko]

Guys, we have just one single snapshot of cell voltages. Before jumping into conclusions, we should see a few more to determine whether the same cells are low and the same cells high all the time.

Also, the BMU itself balances cell voltages during the charging process. To my knowledge, all the dealer procedure does is 'educate the BMU' so that it has a better understanding of the actual capacity rather than just predicated capacity (based on usage pattern). Or do we think there are two different procedures?

 

[PHEV07]

Guys, we have just one single snapshot of cell voltages. Before jumping into conclusions, we should see a few more to determine whether the same cells are low and the same cells high all the time.

Also, the BMU itself balances cell voltages during the charging process. To my knowledge, all the dealer procedure does is 'educate the BMU' so that it has a better understanding of the actual capacity rather than just predicated capacity (based on usage pattern). Or do we think there are two different procedures?

I believe there are 2 different shots of the Cell voltages.

(Post 99983) - 1st shot at about 20% I think rob said (Post 40002). Cells 19, 48, 51,53 and 64 were extremely low compared to others.

(Post 40014) - Second Shot was after full charge. Cells 19 and 64 were extremely low when compared to others

The same 17 cells are lower than the rest.

Not knowing which 8 Cells are used with which of the 10 Modules it is hard to diagnose or try to determine what the issue may be.

One possibility could be that 2 Modules may not be Leveling the cells properly if the Lower Capacity Cells are all in the same 2 Modules.

Also I have no idea if the Dealership does do any Leveling.

Only thing I can do is observe the fact that 17 of the 80 Cells displayed in the Cells Voltage Pictures are lower in value than the rest and some of the 17 as listed above seem problematic.

 

[AndyH]

Guys, we have just one single snapshot of cell voltages. Before jumping into conclusions, we should see a few more to determine whether the same cells are low and the same cells high all the time.

Also, the BMU itself balances cell voltages during the charging process. To my knowledge, all the dealer procedure does is 'educate the BMU' so that it has a better understanding of the actual capacity rather than just predicated capacity (based on usage pattern). Or do we think there are two different procedures?

I don't know the Outlander well enough to talk about how it balances and when. I've hand built small lithium packs for motorcycles and soldered/installed/tested simple management systems. From that perspective for what it's worth... Most BMSs on the market don't start to balance the cells in a pack until the first cell reaches the highest allowable voltage. Whether it's a LiFePO4 cell at 3.6 or 3.65 or 3.7, when the first cell hits the end, it's held there while the rest catch up. Some BMSs convert 'excess' energy to heat, and others move energy from the high cells and 'give' them to the lower cells. The goal is for all of the cells to be at or very near the same voltage when the balancing process is complete.

In more complex systems (from laptop computers to cars), there's basic cell voltage monitoring and there's also a 'fuel gauge' sort of function where a processor tries to guestimate the state of charge (possibly for each cell). Because batteries aren't allowed to get to 100% in most service, and because the 'coulomb counting' process tends to drift from reality, we end up with less 'run time' on the laptop and less range in an EV. On laptops, we have to disable the operating system's 'fuel gauge' protections (like the Windows auto-shutdown when the battery gets to 5% remaining), discharge the battery until the laptop shuts down, and then fully charge the battery as full as it can go so that it'll balance. Then when we re-enable the Windows protection we 'instantly' have gone from 2 hours of run time to 5.
http://www.tomsguide.com/faq/id-2342991/calibrate-battery-windows-laptops.html

As I said at the start, I don't know how the car's supposed to be managing the battery. It appears, though, that there might be a similar 'divergence from reality' drift happening in the car. Here's an example of the effects of smoothing - it appears to be doing something:

https://www.youtube.com/watch?v=3X5dKggJgRk
http://mmc-manuals.ru/manuals/outlander_iii/online/Service_Manual_2013/2016/index_M1.htm

 

[elm70]

Ok app is reporting soh is 94%

Here is the cell graph from 'fully charged' this morning. Cell 19 still low


what is image hosting

Is your car new ?

It is looking like there is a huge unbalance for a single cell ..

Since this happen both full charge and half charged ... actually it is a good thing .. the cell is not damage or weak .. but just off balance

Balancing process allow only to discharge the strong cells, for catch up over the weak cell ... since you have 1 cell weak, and 79 strong the BMU need to discharge 79 cells for balance your pack

You can guess that there is a limited discharge allowed for the BMU for avoid overheat in the BMU module ...

My bet .. is that it will take time before the "weak" cell will get back to same level as the other.

Possibly the smoothing process will speed up this balancing ... but I'm quite sure in time the pack will get balanced automatically

If you don't see any improvement ... it will be good to contact your dealer .. since this unbalance is something to keep under control ... having 1 cell 10% lower then the other, can cause to over discharge this one ...

Keep monitoring the PHEV both after full charge and after usage .. especially when EV range is low or zero ...

If you see this cell going below 3.3v you better contact the dealer .. since at these level you start to cause irreversible damage to the cell.

 

[robdickinson]

New to me, a 2014 car though with 46k kilometres on the clock

 

[elm70]

New to me, a 2014 car though with 46k kilometres on the clock

I would have assume the balancing is all time happening inside the PHEV ... at least while used.

But ... if balance happen only on charging ...

Maybe the previous owner of your car was not charging the car .. still it is strange .... since my PHEV I got 2nd hand and the previous owner did damage the charger, and my PHEV when I got was not getting a charge since months possible well over 1 year.

So ... I would not exclude that there is a defect on the balancing system (BMU)

My PHEV, and others (from the graphs shared by Anko) ... they look like are always able to keep the unbalance under the 0.005v , at least after the full charging is completed.

Anyhow ... if I would be you ... I would keep an eye on it ... if the delta voltage is not going to reduce with time ... better check with Mitsubishi service

0.05v difference is a lot .. and at low charge level it can bring this cell below the "safe" level

 

[AndyH]

FYI...the battery and management tech in our Outlanders is transferred from the iMiev.

I suspect at least a part of the outlander 'cell smoothing' is about recalibrating the computer.

http://myimiev.com/forum/viewtopic.php?p=1031#p1031

I also suspect (but can't yet confirm) that the dealer 'smoothing' process also does a proper balancing that's best done at the top of charge.

If this really is the Outlander CMU, the surface mount resistors can't take a ton of heat, so the balancing current is likely lower than 1A.


http://s936.photobucket.com/user/bigmotherwhale/library/Mitsubishi Phev Pack?sort=3&page=1
http://www.diyelectriccar.com/forums/showthread.php/using-mitsubishi-cmu-bms-lev40-packs-173322.html

So...if the battery's ok, and the BMS/CMU is ok, the battery might slowly come back into balance with regular charging. If regular charging doesn't show improvement, a trip to the dealer might be a good thing.

 

[robdickinson]

Ok so the procedure is basically charge when low..?

I'll monitor it see how it goes.

It's in to the mitsubishi dealer tomorrow for them to find out the wifi details lol

 

[robdickinson]

So 41km indicated range this morning (live on a hill).

23km to work, showing 20km left. Getting most of my commute on ev alone will be great.

Think I'd need at least another 10km to actually get home that hill is a killer