Main Traction Battery Upgrade i-MiEV

[MickeyS70]

I added newer better capacity imiev lev 50 cells (all tested) from another car and over several full discharges below 4km on Gom and subsequent full balance charges the car has now increased its range above 100kms.

Yes, that is correct if you replace LEV with LEV however when you use NMC chemistry the BMU’s capability to recognise the added capacity doesn’t work, unfortunately.

OBDZero did an excellent description of the issue below:
https://www.goingelectric.de/forum/viewtopic.php?t=82690&start=60

From the research into the upgraded CAN bridge it appears the imiev simply has a maximum range on the GOM too. But this could just be forum nonsense as this thread seems to have the code working and I don't know how the code works yet.

It may well be possible that there is a limit how much range the GOM can display, but using 93Ah cells isn’t going anywhere near it…

 

[fresh_milk]

Im not sure this is 100% correct, I added newer better capacity imiev lev 50 cells (all tested) from another car and over several full discharges below 4km on Gom and subsequent full balance charges the car has now increased its range above 100kms.
From the research into the upgraded CAN bridge it appears the imiev simply has a maximum range on the GOM too. But this could just be forum nonsense as this thread seems to have the code working and I don't know how the code works yet.

Forum nonsense
Well put!

 

[hd311]

Hello
Did "GOM" mean "Grafic onboard Monitor" = the Display which is normal in the Car ?

 

[MickeyS70]

Hello
Did "GOM" mean "Grafic onboard Monitor" = the Display which is normal in the Car ?

It means ‘Guess O’ Meter’ as range estimate can be notoriously inaccurate. Not really a fault as it’s based on the ‘consumption’ of the past 15miles.

 

[piev]

Im not sure this is 100% correct, I added newer better capacity imiev lev 50 cells (all tested) from another car and over several full discharges below 4km on Gom and subsequent full balance charges the car has now increased its range above 100kms.
From the research into the upgraded CAN bridge it appears the imiev simply has a maximum range on the GOM too. But this could just be forum nonsense as this thread seems to have the code working and I don't know how the code works yet.

I explained it in several posts and even spoke about the evidence I collected to figure out this solution. I agree with kiev, there are a lot of posts and people get lost on which guys are actually doing the work to figure it out and everyone else. There were a few iterations because some of my assumptions were wrong but I am sure how the car works now. There are two PIDs that are used to estimate range. We refer to them as (PID 0x374) (byte 0) SoC1 and (byte 1) SoC2. One is used by the ECU to calculate the range indicator on the dash often referred to as (GOM) Guess-O-meter because it is not accurate. The other one is used for the bar graph. These numbers are calculated by the BMU and sent to the ECU. We intercept the stream and change the values. The ECU then uses our numbers to determine the range.

 

[Peter Vanhoutteghem]

It means ‘Guess O’ Meter’ as range estimate can be notoriously inaccurate. Not really a fault as it’s based on the ‘consumption’ of the past 15miles.

I just joined this forum and must admit that the jargon/acronyms are not always self explanatory.For other newcomers this might help:
https://www.standard.co.uk/optimist...e-cars-jargon-buster-terminology-b999427.html

 

[hd311]

Hello

Sorry that I have to ask as a Arduino beginner.
I am an Electronic Ing. and have experience with lithium batteries.
I don't know about Arduino and his programming. And I can't really familiarize me either because I have enough other things to do...

I am therefore looking for this as a "service".
Can someone of course do the favor against payment and offer me the hardware + programming?

The installation in my workshop. is no problem.

In the preliminary planning, 93 AH Catl NMC cells were selected. Also that we need adapters to the BMU (BMS) connection.

Here are the following key points:

Citroen C-Zero from 2012 about 90 tsd km
80 cells in 10x 8 modules
Battery capacity is displayed in the Canion with about 26 Ah

New cells:
Catl NMC 93 Ah cells

You can of course send me to a PM
Or: [email protected]
MfG H.Dorsch

 

[MickeyS70]

Hello

Sorry that I have to ask as a Arduino beginner.
I am an Electronic Ing. and have experience with lithium batteries.
I don't know about Arduino and his programming. And I can't really familiarize me either because I have enough other things to do...

In that case leave out the CAN bridge, just replace the cells and reset the battery capacity to 45Ah (using Lexia/Diagbox) which will almost double your client’s current range…

 

[hd311]

Where can I get the LEXIO / Diagbox?

You write that the current range has doubled, so it would have the same range as the car originally had.
The customer has already read that with the current battery development, around twice the range (i.e. more than 200km) is possible. And that is exactly what he is focusing on.
He has also already driven a BMW i3 with 60 and 120 Ah, and here too, the range has doubled with the same battery dimensions

 

[MickeyS70]

Where can I get the LEXIO / Diagbox?

The easy answer first:
https://myimiev.com/threads/using-t...re-adapter-as-a-universal-j2534-adapter.5594/

The customer has already read that with the current battery development, around twice the range (i.e. more than 200km) is possible. And that is exactly what he is focusing on.
He has also already driven a BMW i3 with 60 and 120 Ah, and here too, the range has doubled with the same battery dimensions

To achieve the original range with a triplet you need to do two things:
1. replace the 88/80 OEM cells with something suitable, e.g NMC93 (purely “nuts and bolts” type of work, but with the added challenges of a High Voltage DC environment)
2a. reset the battery capacity to 45Ah

If you want to have a 200+km range
2b. increase the max useable BMU capacity to match the new cells (using a CAN bridge)

You seem to be comfortable with 1. but want to ‘subcontract’ 2b. if I understand correctly.

Thanks to the great work by members of this forum (in particularly the ‘test pilot/engineer’ @piev and the ‘all round BMU genius/appDeveloper” @CZeroOwner) the current Arduino code is essentially still a ‘work in progress’.

The goal is to freely share the knowledge gained, not to sell ‘black boxes’ as that would require a ‘foolproof level of programming’ and could have serious legal implications should something go horribly wrong.

There are commercial solutions available, see below
https://ozelectricvehicles.com.au/pages/licensed-installers

 

[CeeJay09]

Hi all, I have been trying to find a reliable supplier of NMC93Ah cells with no luck, the contact I was planning to use in Australia can no longer source these cells either (not OZ DIY). Has anyone recently ordered or found a supplier with 176 of these cells (for 2 Imievs)?

 

[piev]

Hi all, I have been trying to find a reliable supplier of NMC93Ah cells with no luck, the contact I was planning to use in Australia can no longer source these cells either (not OZ DIY). Has anyone recently ordered or found a supplier with 176 of these cells (for 2 Imievs)?

Starmax High Power Catl 3.7V 93Ah Rechargeable Nmc Lithium Ion Batteries Ncm 93Ah 3.7V Lithium Battery Prismatic Cell for DIY EV​

https://www.alibaba.com/product-det...offerlist.normal_offer.d_title.33f72a9dlAL2Ig

 

[Negue]

https://m.alibaba.com/x/AxAyOA?ck=pdp

Is a better price but shipping seems to be double then cell :/

 

[UniqueRelic]

I will probably be upgrading my battery pack after t his Canadian winter.
as I'm about 50% degraded (only 50-60km max range with no heat, ac radio etc)
I got a good price delivered from xihobattery.com I plan on purchasing 88 of these sometime in march if still available.
and using this guide to hopefully extend the range.
like the gentleman above I have no issues tackling the actual battery upgrade. may need some assistance with the canbus mods

my 2012 i-miev has 54,000 km on it

so from my understanding putting in the catl93ah wont double the range by itself without the canbus + experimental code
awesome job by the way

I have access to a high km i-miev with 184,000km that battery is shot
and may use that as a test rig + donor car if I blow something up

 

[Negue]

https://m.alibaba.com/x/AxDUbP?ck=pdp

Starmax High Power Catl 3.7V 93Ah Rechargeable Nmc Lithium Ion Batteries Ncm 93Ah 3.7V Lithium Battery Prismatic Cell for DIY EV​

https://www.alibaba.com/product-det...offerlist.normal_offer.d_title.33f72a9dlAL2Ig

https://m.alibaba.com/x/AxDUbP?ck=pdp

I hope to have space for it.
Will not stay in original position but at better price(25$showd me) a 125ah( from 94ah ) with arrangement complication :/

Space 385x650x190 and 125ah cell dimension 103*300*28 will have 3*2*6.7 (28mm*7cells = 196 mm)
I think thous 6mm will gain if I lowering case or top case will be 6mm higher.

Indeed, I calculated full but I need to figured out where to put the BMS's :/

Need to calculate if I can put 2 125ah cells in slide module (4 separate central cells)

I will ask seller tomorrow how much will be DDP

 

[Negue]

I will probably be upgrading my battery pack after t his Canadian winter.
as I'm about 50% degraded (only 50-60km max range with no heat, ac radio etc)
I got a good price delivered from xihobattery.com I plan on purchasing 88 of these sometime in march if still available.
and using this guide to hopefully extend the range.
like the gentleman above I have no issues tackling the actual battery upgrade. may need some assistance with the canbus mods

my 2012 i-miev has 54,000 km on it

so from my understanding putting in the catl93ah wont double the range by itself without the canbus + experimental code
awesome job by the way

I have access to a high km i-miev with 184,000km that battery is shot
and may use that as a test rig + donor car if I blow something up

They say that cell have 172mm and I know the Lev50 is 171mm :/

 

[mradtke]

Hello,

I worked with piev through his process of upgrading the iMiEV pack. I wasn't able to contribute much, so this post is mostly to confirm that it works. I've been driving my upgraded car for a few weeks now with no issues, and double the original range.

I am hoping to contribute a little more to those who follow. For instance:

My son is working to document the simple and safe method of removing the pack that we used with commonly available tools.

My son is also documenting the process that we used to replace the OEM LV50 cells with the NCM 93Ah cells.

I used the togglebit CANFDuino product instead of the Arduino DUE that piev used for the CAN bus "Man In The Middle." I did a direct port of piev's code, only making the minimal modifications necessary for the CANFDuino environment. I plan to port the future changes that piev might make, and will make my code available. (piev did a simiar port as well.)

I will also document the car connections to the togglebit CANFDuino.

I am extremely grateful to piev for his efforts as well as the others who contributed to this project.

Mike

 

[MickeyS70]

My son is working to document the simple and safe method of removing the pack that we used with commonly available tools.

My son is also documenting the process that we used to replace the OEM LV50 cells with the NCM 93Ah cells.

I appreciate your and your son’s desire to make a simple step by step guide to upgrade the traction battery to NMC.

I worry though, that if such instruction were to be published, it may encourage individuals without the necessary basic skills to ‘have a go’ which may lead to potentially catastrophic and deadly outcomes.

Despite best efforts ye will never be able to make a truly ‘fool proof’ guide.

IMHO, (thanks to the many contributors on this and other forums) there is just enough information out there for the ‘well informed’ to succeed and discourage others not to ‘try this at home’…

 

[jray3]

I appreciate the balance that MickeyS70 is trying to strike by making folks do their homework, but I'll vote in favor of Mike publishing his guide. DIY EV converters kept the electric dream alive for most of the interval between the 1930's and the 2010's, and are the only way that any significant numbers of these cars will survive around the world. My first EV book, "Convert It" by Mike Brown, was spiral-bound on mimeograph paper by a barely literate hippie mechanic, and TESLA and other successful EV companies were founded by the 'poorly informed', as all the experts said it couldn't be done or wouldn't make a profit. The USA is currently being infected with a "nanny state" mentality that took over much of the western world ages ago, with OEMs led by Toyota lobbying states to require licensing of EV battery technicians and ban DIY repairs. They'll have to pry my multimeter out of my charred, stiff fingers first! (rant mode off)

 

[Phximiev]

Having visited and watched mradtke and his son from time to time in the process, I am of the belief that their documentation of the process they followed will be both thorough and safe to follow. I was and continue to be amazed at their organization and methodical approach. Also, there are numerous examples of those without "the necessary basic skills" succeeding in repairing a complex electrical/mechanical device.