PV1
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Location: Pittsburgh, PA

Re: Future battery replacement

Mon Mar 31, 2014 7:39 am

That's one of the big things I wonder about this is how to get the car to access the expanded capacity of the new cells, unless that's what the turtle is for. I would imagine the car counts kWh to run the charge gauge and RR, but once it thinks the battery is "empty" (no bars and '---' RR), it will resort to turtle (a low power mode) and watch the voltage until one or more cells hits LVC. It should then be able to re-calibrate from the new empty point and have access to the full 29 kWh of available capacity.

I guess it'll take one of us actually doing it to find out if the i-MiEV functions like this. If the car won't use the full capacity of the new pack...well, someone has an awesome battery pack for backup power or off-grid solar.
"Bear" - 2012 Diamond White Pearl ES with QC - 2/21/2013
"Koorz" - 2012 Cool Silver Metallic ES with QC - 1/5/2015
"Photon" - 2017 Bolt EV LT in Orange with QC - 7/31/2017

Solar-powered since 10/10/2013

Don
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Re: Future battery replacement

Mon Mar 31, 2014 8:31 am

I would bet that in a car so sophisticated that replacing the center brake light bulb with an LED causes an error and running with a spare tire a little smaller (or larger) than the one it replaces causes an error, we're going to find all sorts of errors when we try replacing the battery pack with something . . . . better

I suspect all sorts of things won't work correctly, from the BMS to the RR calculations to the Turtle . . . . heck, it might not even charge correctly. When/if Mitsu comes out with an all new 24Kwh battery pack a year or two from now, it likely won't be a drop-in replacement for our pack either, at least not without a significant reprogramming of the car's computer. The benefit of buying it from Mitsu though will be that their engineers will likely do the programming to make it all work correctly

That said, I LOVE surprises - When one of you gets a new 29Kwh pack installed and functioning properly, I'll be as elated as anyone here! . . . . I just suspect that there will be all sorts of snags to overcome before anyone gets there

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

MLucas
Posts: 833
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Location: Niagara on the Lake, Ontario, Canada

Re: Future battery replacement

Tue Apr 01, 2014 8:42 am

If that flooded Mitsubishi is still available, maybe we can crowd source the funding to give this a go. :lol:

Like Dylan...I went electric.

  • Purchased: June 29th, 2012
  • Mileage on June 29th, 2013 - 25,431 km / 15,802 miles
  • Mileage on June 29th, 2014 - 51,286 km / 32,616 miles

List of Oil Spills: http://en.wikipedia.org/wiki/List_of_oil_spills

Malm
Posts: 449
Joined: Mon Jul 22, 2013 12:16 pm
Location: Tábua - Portugal

Re: Future battery replacement

Tue Apr 01, 2014 9:23 am

PV1 wrote:That's one of the big things I wonder about this is how to get the car to access the expanded capacity of the new cells, unless that's what the turtle is for. I would imagine the car counts kWh to run the charge gauge and RR, but once it thinks the battery is "empty" (no bars and '---' RR), it will resort to turtle (a low power mode) and watch the voltage until one or more cells hits LVC. It should then be able to re-calibrate from the new empty point and have access to the full 29 kWh of available capacity.

I guess it'll take one of us actually doing it to find out if the i-MiEV functions like this. If the car won't use the full capacity of the new pack...well, someone has an awesome battery pack for backup power or off-grid solar.


I see it very easy. I think is just easy as this: Add the entire complete modules, with their electronics. Then just connect them. Then just replace in the software the number 16 kWh by 29 kWh. The car will then know that every 5% bar will correspond to something like 1,5 kWh and turtle will only be there when it has only 2,9 kWh. We all know that there are Peugeot Ion of 14,5 kWh - they show all the 16 bars. The diference is that they know that 100% SoC is 14,5 kWh.

I´m sure it will not recalibrate by himself so easily. It knows that tomorow it could have 10% less capacity because temperatures had go down 20ºC or something like that. So, it will not do that for one day to the other.

For me, I don't see a reason why it should be dificult to add 8, 16 or 24 more cells, Peugeot did it, taking 8. My car did it, 16 bars (Turtle - 10%, 2% ---, 5%, 5%, 6%, 6%, 6%, 5%, 5%, 5%, 5%, 5%, 5%, 5%, 5%, 5%, 7%, 8% SoC), all perfect. I mean exactly all perfect. All by himself (i think). How this is possible, well, one miracle happened, in the first days of March, it recalculated his capacity to 12,75 kWh. In february, I had a 16 kWh i-MiEV but i could stop with the car showing something like 14,5% SoC. Now, well, I just keep going until it gets to 0,0%.

3 years (exactly), something like 63.500 km, 15º C medium ambient temperature, and an 12,75 kWh i-MiEV - Believe it or not. I'm sure about what i'm telling you. The canary keeps singing.
Riding an i-Miev since 4/2011 in Portugal, 100.000 kms.

PV1
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Re: Future battery replacement

Tue Apr 01, 2014 9:49 am

MLucas wrote:If that flooded Mitsubishi is still available, maybe we can crowd source the funding to give this a go. :lol:

That sounds like a neat idea. How much to build a cell?
"Bear" - 2012 Diamond White Pearl ES with QC - 2/21/2013
"Koorz" - 2012 Cool Silver Metallic ES with QC - 1/5/2015
"Photon" - 2017 Bolt EV LT in Orange with QC - 7/31/2017

Solar-powered since 10/10/2013

JoeS
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Location: Silicon Valley, California

Re: Future battery replacement

Tue Apr 01, 2014 11:08 am

Malm wrote:I see it very easy. I think is just easy as this: Add the entire complete modules, with their electronics. Then just connect them. Then just replace in the software the number 16 kWh by 29 kWh.....For me, I don't see a reason why it should be dificult to add 8, 16 or 24 more cells, Peugeot did it, taking 8. ...
I'm assuming you're talking about adding these cells in series, boosting system voltage (what's it's upper limit?)? In any case, you have some significant repackaging and rewiring to do and, assuming you've got a balancing circuit on each cell, how do you now integrate the individual cell monitoring into the system, not to mention how exactly do you do the software mods? Not trivial, IMO, unless you have access to the Mitsu design team.
Malm wrote:... How this is possible, well, one miracle happened, in the first days of March, it recalculated his capacity to 12,75 kWh. In february, I had a 16 kWh i-MiEV but i could stop with the car showing something like 14,5% SoC. Now, well, I just keep going until it gets to 0,0%.
Malm, that's interesting - you're saying the software did a recalculation and established 12.75kWh as your new capacity? How did you figure this out and where/how did you get this new vs. old capacity reading?
EVs: 2 Wht/Blu SE Prem., '13 Tesla MS85, 3 156v CorbinSparrows (2 Li-ion), 24v EcoScoot(LiFePO4)
EV Conv: 156v '86 Ram PU, 144v '65 Saab 96
Hybrids: 48v1kW bike
ICE: '88 Isuzu Trooper. Mothballed: '67 Saab (orig.owner), '76 MBZ L206D RHD RV

Malm
Posts: 449
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Location: Tábua - Portugal

Re: Future battery replacement

Tue Apr 01, 2014 1:15 pm

I know that is not has simple as i said, but peugeot did in fact made them of 14,5.

Ok. I think assuming that it was of 16 kWh when new is consensual. I remember to charge, two years ago, something like 16,6 kWh from the charger, with some SoC in the battery. So I assume it taked, maximum, 16 kWh in the battery. Each bar of 5% used exactly 0,8 kWh from the battery. But now, every bar of 5% uses something like 0,64 kWh. I see it in Canion, I use now 6,4 kWh (more or less), and one bar of 5% goes away. And now I do clearly less km with each bar as compared with february. But in february, I could see two bars going away or stop with 14,5% SoC because one cell reached 2,75 V. Now I stop with 0,0% of SoC and my worst cell is far away from 2,75 V. Now, from 0% to 100%, I will use from the charger 14,6 kWh (in february I remenber to use regularly more then 15 kWh).

Now I will show things that you never saw, made by Malm and its portuguese I-MiEV. I know that getting the car so low is not good (sorry for that :oops: ). Well, this time, with 0,0% SoC I was far from getting to one cell 2,75 V. But that happened with 14,5% of SoC. I think getting to 0,0% SoC this time was not so bad.

Driving an I-MiEV with 0,5% SoC is possible. Not try this, that will only be possible with a perfect new I-MiEV, or with mine (for now, your time will came, some day).

https://www.youtube.com/watch?v=PkWW5w2e4XU
Riding an i-Miev since 4/2011 in Portugal, 100.000 kms.

PV1
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Re: Future battery replacement

Tue Apr 01, 2014 1:24 pm

So, when it hit 0% SoC, did it come out of READY? I noticed at .5% you could move around with READY lit, but at the end the READY light was off.
"Bear" - 2012 Diamond White Pearl ES with QC - 2/21/2013
"Koorz" - 2012 Cool Silver Metallic ES with QC - 1/5/2015
"Photon" - 2017 Bolt EV LT in Orange with QC - 7/31/2017

Solar-powered since 10/10/2013

Malm
Posts: 449
Joined: Mon Jul 22, 2013 12:16 pm
Location: Tábua - Portugal

Re: Future battery replacement

Tue Apr 01, 2014 1:34 pm

PV1 wrote:So, when it hit 0% SoC, did it come out of READY? I noticed at .5% you could move around with READY lit, but at the end the READY light was off.


Yes, with 0.0 SoC, no more Ready. It assumes that it is tottaly empty (but it wasn't, 3,25 V for the weakest cell, not 2,75). In the exact moment that it hit 0,0 SoC, Ready go away.
Riding an i-Miev since 4/2011 in Portugal, 100.000 kms.

PV1
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Location: Pittsburgh, PA

Re: Future battery replacement

Tue Apr 01, 2014 2:23 pm

Well that puts a wrench in the plans.

Maybe it'll work the other way. Run the i-MiEV down to turtle, install the new pack discharged, and charge it with the i-MiEV. Maybe during the recalibration is when the kWh counter is largely ignored.
"Bear" - 2012 Diamond White Pearl ES with QC - 2/21/2013
"Koorz" - 2012 Cool Silver Metallic ES with QC - 1/5/2015
"Photon" - 2017 Bolt EV LT in Orange with QC - 7/31/2017

Solar-powered since 10/10/2013

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