thomash85715
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When to be concerned about Ah number

Sun Oct 27, 2019 12:27 pm

I just found the readout on CANiON for my 2012 with around 25K miles on it. 35.6 is the figure showing after the latest level one overnight charge from factory EVSE. People on another forum seem to think it should be 42. At what point does mitsubishi replace the main pack under warranty? I still have till january of 2021 on my car since it sat unsold until january of 2013. I am getting around 72 miles on a charge and that is using zero climate control and hand signals for turning and other means of stretching the power. The aux battery was replaced about a year ago after it had tested around 40% at the dealer. Thank you.
In an insane society a sane man would appear insane.
Acquired 2012 silver ES April 2017.

Gary12345
Posts: 50
Joined: Tue Feb 12, 2019 4:15 am
Location: Essex, UK

Re: When to be concerned about Ah number

Mon Oct 28, 2019 9:09 am

What does the warranty state about expected degradation? 35.6Ah is about right for the age of vehicle, that is about 77% battery health (based on 46Ah for a new vehicle). I doubt the warranty protects you against natural degradation, i've heard about pack replacements under warranty but that is where the vehicle would have major issues like it would not charge fully or only go 20 miles then stop.

What is the variance in cell voltage at around 20% state of charge? That will show any failing cells. If the voltage is pretty similar then it is just natural degradation of the batteries over time.

Cheers.

thomash85715
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Joined: Sat Apr 01, 2017 9:05 am
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Re: When to be concerned about Ah number

Mon Oct 28, 2019 12:29 pm

There is a guy named gary on the FB page for our cars; is that you? Yes I will look at canIon individual voltages when I get down to 3 bars and see what it says. Lately I have noticed that number 64 is running hotter than the others during charge. It is up around 29C while others tend toward 26 or 27. Thank you.
In an insane society a sane man would appear insane.
Acquired 2012 silver ES April 2017.

kiev
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Re: When to be concerned about Ah number

Tue Oct 29, 2019 8:48 am

How far is your daily commute? With 72RR you are obviously a good driver in eco mode to stretch your mileage, but i doubt you are driving that far in a day.

My guess is that with your pack, you could drive about 52 miles from Full to Empty and maybe hitting the Turtle too.

So i would say to Never be concerned about the Ah number. There is nothing that you can do about it, and as long as the car meets your daily needs then it is not a problem.

If you have an issue with the pack that would be replaced under warranty, then the max cell voltage difference will be very large and the car will no longer charge to Full 16 bars. The Ah number has nothing to do with warranty replacement, but it will affect your actual maximum possible driving distance.
kiev = kenny's innovative electric vehicle

Don
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Re: When to be concerned about Ah number

Tue Oct 29, 2019 5:45 pm

To the best of my knowledge, Mitsu never replaces the traction battery due to loss of capacity. When we bought our first 2012 new in May of 2012, the dealer explained that the warranty was for battery failure only and that a reduction in capacity over time was to be expected . . . . and then he had us sign a statement that we understood that

I do recall reading (here??) about one case where the car was still charging fully, but the capacity was so bad they were down to only 30 or 35 miles and after much cajoling and excellent support from their particular dealership, Mitsu did eventually give them a new battery under warranty . . . . but if you're still getting 72 miles per charge, you're light years away from Mitsu every agreeing to do anything about your battery

One of my cars is not charging correctly and I'm patiently waiting for the battery to fail. It almost never charges to 16 bars, usually just 15 and that 15th bar goes away really quickly, sometimes after only a mile or two. Once or twice it has stopped charging at 14 bars. I suspect a cell or two is failing, but it's taking it's time about doing getting there - This has been going on for a couple months

I'd LOVE to eventually get a new battery, even though it means I'll have to trailer the car to my nearest dealer 110 miles away, so when it happens, I'll get it there somehow!

Don
2012 iMiEV SE Premium, White
2012 iMiEV SE, White
2017 Chevy Volt Premier
2014 Ford Transit Connect XLT SWB wagon, 14,000 miles
1979 Honda CBX six into six

Gary12345
Posts: 50
Joined: Tue Feb 12, 2019 4:15 am
Location: Essex, UK

Re: When to be concerned about Ah number

Thu Oct 31, 2019 8:50 am

thomash85715 wrote:There is a guy named gary on the FB page for our cars; is that you? Yes I will look at canIon individual voltages when I get down to 3 bars and see what it says. Lately I have noticed that number 64 is running hotter than the others during charge. It is up around 29C while others tend toward 26 or 27. Thank you.


Yes that is me !

There are only 66 temp sensors for 88 cells so the temp sensors are not evenly placed, some variation can be expected.

Your Ah figure is normal for the year. As long as the cells are fairly evenly matched at a low state of charge then its just natural degredation.

Thanks.

DBMandrake
Posts: 250
Joined: Mon Mar 20, 2017 4:57 am
Location: Scotland

Re: When to be concerned about Ah number

Fri Nov 01, 2019 3:15 am

In my opinion, 35.6Ah from a 7 year old car with only 25K miles on it is quite a bit below where it should be. My car was at 39.9Ah at 28K miles and 6 years old, and you can see the story of battery degradation for my car after that point in this thread:

viewtopic.php?f=23&t=4014&start=50#p39013

My car hit 35.6Ah at 46K miles and 7 years old, and this was after three cells developed a fault that has caused progressive rapid degradation of those specific cells ever since.

It would certainly be interesting to see the Canion cell voltage page with your car at 20% SoC to see whether your 35.6Ah is due to overall degradation of all cells or whether it is a small number of bad cells as in my case.
- Simon

EV: 2011 Peugeot Ion
ICE: 1997 Citroen Xantia V6

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