Main Traction Battery Upgrade i-MiEV

[puh]

Hi Chris,

I paid $3,681 for 93 cells including tax and shipping in April. The car uses 88 cells. The rest were spares.

You need to consider the risk and safety precautions of dealing with high voltages. In addition, the pack rebuild is a lot of work. My son is working on some step by step instructions for the process. I will post a link here when he is satisfied with the content.

Our car is working just fine and I'm pleased with the result.

Mike - Phoenix, AZ

Thank you very much for this brilliant guide on replacing battery cells, your efforts are hard to overstate!

I would like to clarify - have you tried to get a special discount on the price of the cells on alibaba?

Because now the price seems to have increased significantly...

 

[Daniel11]

Salut Chris,

J'ai payé 3 681 $ pour 93 cellules, taxes et frais de port compris, en avril. La voiture utilise 88 cellules. Le reste était des pièces de rechange.

Vous devez tenir compte des risques et des précautions de sécurité liés à la manipulation de hautes tensions. De plus, la reconstruction du pack demande beaucoup de travail. Mon fils travaille sur des instructions étape par étape pour le processus. Je publierai un lien ici lorsqu'il sera satisfait du contenu.

Notre voiture fonctionne très bien et je suis satisfait du résultat.

Mike - Phoenix, Arizona

Bonjour,
Ou avez-vous commandé vos bateries
merci

 

[MickeyS70]

Hello,
Where did you order your batteries
Thank you

See post #212

 

[mradtke]

See post #212

I ordered these cells:

https://www.alibaba.com/product-det...8.html?spm=a2700.wholesale.0.0.256e30b1jevR7c

I searched on alibaba.com today for cells with similar specifications, and found that there are other vendors selling these cells at about the same price, not "significantly higher."

Mike

 

[piev]

What about if I went with LFP instead eventually when I do this?

What Kiev said is true but the bigger issue with LFP is the voltage. The NMC cells are charged to 4.15v or 4.1v I can’t remember but LFP cells can only be charged to 3.65V. I believe you would need to completely replace the BMU or reprogram it and perhaps the CMUs. Their may be others here that know more details but it would be a considerable effort.

I will say I have thought of doing this but could find no documentation on the BMU processor to reprogram it. YUASA does make a LFP cell in the same form factor.
Yuasa LFP Cell LEV60

 

[MickeyS70]

What Kiev said is true but the bigger issue with LFP is the voltage. The NMC cells are charged to 4.15v or 4.1v I can’t remember but LFP cells can only be charged to 3.65V. I believe you would need to completely replace the BMU or reprogram it and perhaps the CMUs. There may be others here that know more details but it would be a considerable effort.

Not necessarily, in theory one could use a second can bridge on BAT-CAN and add a .45V offset to any voltage reported from the CMU. What may be trickier is to determine a reliable voltage based SoC algorithm due to almost flat discharge curves?

YUASA does make a LFP cell in the same form factor.
Yuasa LFP Cell LEV60

Great find..

 

[Jiminy]

Besides chemistry, the 55mm thickness on LEV60F would also be an issue...