2011 ZE0 40KWH cell swap, SOH reset, CAN flash?

[dgray477]

Hey team,

I have been following with enthusiasm and finally got some G3 2018 40KWH cells that all tested at 103AH of capacity. I pulled my 2011 pack apart and swapped the cells. I'm using the original bms and everything so far is going ok (few days of driving it). Few questions:

I was reading that the original software can be a bit buggy to CAN flash, and if so, to regain the miles/SOH bars, is it an option to take it into Nissan and have them reset the SOH on the current bms/pack??

Should I attempt a CAN flash anyway to just see the difference and if it goes back to 100% and fixes the Miles? Gids, SOC, and SOH?

So far, I can drive it way past the distance on the dash and it still hasn't gone into turtle mode, the miles just go to 3 dashes. I'm still getting P33D4-00 0E HV Battery Bat Int Resistance Diag EVB-130 (not sure how it's measuring the cells). I have 1 cell that is 63MV low(just needs a bit more charging, so I'll pull pack apart and charge up that module )

Thanks for the help!

 

[Stanton]

Should I attempt a CAN flash anyway to just see the difference and if it goes back to 100% and fixes the Miles? Gids, SOC, and SOH?

What kind of CAN flash are you talking about? Is it a third party CAN-bridge? Or part of the original equipment?
If you have put 40 kWh cells into a 24 kWh pack (I swapped the whole pack), I don't see where you will ever get proper readings/operation without some sort CAN-bridge. And I don't think Nissan will even touch the car once you tell them what you've done (even if they could reset something like SOH).

 

[dgray477]

Ok, great. Yes I was talking about the can-bridge install. Yeah I had a feeling that was the case. I'll install the can-bridge and see what happens. Thanks!

 

[MikeinPA]

I am very interested in what you are doing! There are tons of people with more knowledge on this, but here is my two cents.

The can bridge is only used if you change the BMS up from a 24 kwh BMS. You did not, so no can bridge is needed. Also, the 2011 2012 BMS and warning harness are not interchangeable with later components, so you cannot simply add a 40 kwh BMS. It is possible to reset the BMS, but AFAIK that is still dealer only. I would very much doubt they would help.

The BMS is built for a 24 kwh pack. As it learns the new cell capacity, it should slowly update itself upward. Whether that will stop at 24 kwh or keep going is a neat question. In the meantime, you should use Leaf Spy to keep track of miles remaining and balance condition.

Also, be aware that this battery pack is no longer a fully certified configuration. As far as I know, there have been very few fires with Leaf packs. But, think carefully about reselling the vehicle, or letting you insurance company know.

 

[Stanton]

The BMS is built for a 24 kwh pack. As it learns the new cell capacity, it should slowly update itself upward. Whether that will stop at 24 kwh or keep going is a neat question. In the meantime, you should use Leaf Spy to keep track of miles remaining and balance condition.

This is really a "Dala question", but I'm pretty sure the BMS does not recognize the "new" modules, so therefore will never properly display capacity.

Also, be aware that this battery pack is no longer a fully certified configuration. As far as I know, there have been very few fires with Leaf packs. But, think carefully about reselling the vehicle, or letting you insurance company know.

As for reselling, battery pack capacity upgrades should be well received by an (experienced) EV buyer.
However, I wouldn't mention battery pack mods to your insurance company...unless you don't really want car insurance. Just sayin'.

 

[dgray477]

Super interesting results. the SOH has increased to 6 bars, and 60%. the AH has been increasing. I'll be interested after I charge the low cell if the it increases faster, but the dash check lights have gone out.

 

[MikeinPA]

Super interesting indeed. The BMS is clearly adjusting upward at its own pace. This may take a while! I will be very interested to see what happen once the amp hours exceed ~65. Will it keep going?

I am also seeing increasing amp hours after replacing three modules in my 2013 as the BMS is adapting.

If you have the gasketed battery enclosure, I am somewhat jealous. The 2013 forward are sealed with special (expensive) sealant which is a pain to reinstall properly.

About the swap. Were the temp sensors easy to reinstall? Was the mechanical hold downs compatible?

 

[dgray477]

Update. So far so good, pack health and AH keep climbing. getting close to the 66AH new value, so here's hoping. Range now says 82 Miles up from original 43.

 

[dgray477]

Update: so far so good. Miles at 70 degrees are 108 and the SOH is at 92%.

 

[brbill]

How's it looking now? My 2011 Leaf at 63K miles has an effective range of about 30 (displays 37). I've been interested in doing cell replacement for years, but wasn't sure where to get the cells, and am only driving about 1000 miles a year nowadays. The yearly costs of insurance and registration is probably about what I would spend for annual bus pass plus a decent e-bike.

 

[TobyHolland]

It is universally accepted by all of us #LeafBatteryUpgrade suppliers that can do this 'forced' upgrade, it NEVER works as well as installing a complete 40kwh pack, complete - especially as individual matching 40kwh cells are REALLY hard to find.......it IS possible to reflash the BMS to improve the way it tries to deal with the 40kwh cells, but of course it's extra time and cost whilst the pack is open......
It's probably acceptable for a DIYer, but for Retail Clients this way would never be acceptable