Dala's Leaf buildthread (2015 Nissan Leaf)

Omien autoprojektien esittely.
HiTec
SUPPORTER
SUPPORTER
Posts: 252
Joined: 20. Feb 2012 16:54

Re: Dala's Leaf buildthread (2015 Nissan Leaf)

Post by HiTec » 29. May 2020 20:09

Those are pretty easy to solder with magnifying glass, tweezers, soldering paste (not flux, paste) and soldering station. Preferably hot air station, but the regular temp adjustable soldering station is also okay, as long as it has a fine tip.

User avatar
Dala
SUPPORTER
SUPPORTER
Posts: 212
Joined: 14. Oct 2014 19:39
Location: Vaasa

Re: Dala's Leaf buildthread (2015 Nissan Leaf)

Post by Dala » 29. May 2020 22:34

For one single card yes, but I need to guarantee that the finished product holds up for 10-15years on customer cars, along with making tens if not up to a hundred of these. So I need to get some well needed precision tools into the mix :D

User avatar
Dala
SUPPORTER
SUPPORTER
Posts: 212
Joined: 14. Oct 2014 19:39
Location: Vaasa

Re: Dala's Leaf buildthread (2015 Nissan Leaf)

Post by Dala » 02. Jun 2020 11:27

So here's something that's good to know when testing used batteries. I recently examined the 40kWh that is soon going into a customer car, and found a small puncture in the top casing. After informing the customer, and then repairing the small puncture, it was time to pressure test the battery.

So a bit about pressure testing. The batteries are by design "waterproof", this specific model can be fully submerged for a few hours without any issues. But they aren't 100% waterproof, some water will get in thru the high voltage harness pins overtime, so it's not possible to store the batteries underwater. So to test the batteries, a pressure tester is needed. There is an official tool, but since it's not possible to buy it I'll have to make my own.

Here is the port on the battery used for testing. It's just a bolt with a copper washer, next to the high voltage connections.
Image

And here is my improvised tool using some scraps. It's just the same bolt type, with a hole drilled thru it. I put some threads into the bolt head, and attached a hardline pipe and hose to it. It then gets a bike tire pressure valve on the end, which a normal bike pump can be attached to. Tada, 0€ testing tool.
Image

And finally here is the official procedure from the FullServiceManual.
Image
Image
Image
Image

And yes, the battery passed the test :)

User avatar
Dala
SUPPORTER
SUPPORTER
Posts: 212
Joined: 14. Oct 2014 19:39
Location: Vaasa

Re: Dala's Leaf buildthread (2015 Nissan Leaf)

Post by Dala » 02. Jun 2020 17:13

I am on a roll. I'm now releasing this to the public, so anyone looking for an easy way to pair ZE0 batteries, feel free to try it out :) But read the fine print, very untested still!

https://github.com/dalathegreat/Nissan- ... eryPairing

Image

User avatar
Dala
SUPPORTER
SUPPORTER
Posts: 212
Joined: 14. Oct 2014 19:39
Location: Vaasa

Re: Dala's Leaf buildthread (2015 Nissan Leaf)

Post by Dala » 04. Jun 2020 09:30

So I've noticed that the right hand passenger door makes quite the amount of noise. Any extra squeeks or rattles is extremely noticeable in an electric car, so I need to fix this.

Started with removing the door trim. All you need is a PH2 screwdriver.
Image

Here is what the sound was like
https://youtu.be/pwH8oro5MG8 

I fixed it by bending the metal inside the door with my bare hands. That says a lot about the thickness :)

User avatar
Dala
SUPPORTER
SUPPORTER
Posts: 212
Joined: 14. Oct 2014 19:39
Location: Vaasa

Re: Dala's Leaf buildthread (2015 Nissan Leaf)

Post by Dala » 07. Jun 2020 10:38

Here's something to keep in mind if you're a Nissan Leaf owner. A year ago, July 2019, Nissan issues a service campaign where you could get the battery bonding plates updated for free. Supposedly they would rust heavily and not offer enough electrical conductivity. https://nna.secure.force.com/recall?camp=P9312

The bonding plates, aka grounding straps, are used to securely ground the battery to the chassis. When there is a secure connection it is possible to detect loss of isolation between high voltage positive and negative terminals. If the grounding is flaky, HV could short to chassis GND outside the battery, and the battery LBC could potentially miss this. So it's a very important safety feature.

This weekend I saw the first bonding plate failure on a customer car. Take a look at this!

The mounting bolt was snapped off
Image

For illustration purposes, here is a grounding strap attached
Image

I did a complete battery replacement, so got rid of the heavy corrosion that was on the battery. I also replaced the grounding straps with cleaner ones, and made it tip top. In the FSM, it specifies a 0.1 Ohm maximum resistance between chassis and battery, really wish I would have measured that before removing that mess, since it looks like it would have failed that for sure!

All fixed now :)

User avatar
Sammyboi
SUPPORTER
SUPPORTER
Posts: 151
Joined: 01. Aug 2015 01:49
Location: Oulu

Re: Dala's Leaf buildthread (2015 Nissan Leaf)

Post by Sammyboi » 07. Jun 2020 16:51

Well that is definitely hair raising.

Talk about a bad ground.. :o

User avatar
Dala
SUPPORTER
SUPPORTER
Posts: 212
Joined: 14. Oct 2014 19:39
Location: Vaasa

Re: Dala's Leaf buildthread (2015 Nissan Leaf)

Post by Dala » 07. Jun 2020 21:41

Yeah I was "shocked" to see it that bad :D

Tonight I did some more CAN-decoding. The Audio/Video (AV-CAN) is not very well documented on the Leaf. A recent discovery by Jonas Andersson piqued my interest, check this out:



Now to explain more what is happening here. Due to GDPR, the higher spec Nissan LEAF models with the infotainment have a startup nag-screen. This screen has you press ACCEPT to all telemetrics before being able to use the display. By injecting a CAN-message to the AV-CAN, it is possible to bypass this nag-screen and go straight to radio/maps.

So I did what I do, and put the AV-CAN information onto the CAN message database. Anyone wanting to check out more on the AV-CAN, it is now here: https://github.com/dalathegreat/leaf_ca ... AV-CAN.dbc

It is possible to create this as an optional add-on to the CAN-bridges I install, so that it would automatically bypass this screen. I'll have to do some market research to see if it is even wanted :)

HiTec
SUPPORTER
SUPPORTER
Posts: 252
Joined: 20. Feb 2012 16:54

Re: Dala's Leaf buildthread (2015 Nissan Leaf)

Post by HiTec » 07. Jun 2020 22:22

Is that battery strap and the bolt aluminum?

User avatar
Dala
SUPPORTER
SUPPORTER
Posts: 212
Joined: 14. Oct 2014 19:39
Location: Vaasa

Re: Dala's Leaf buildthread (2015 Nissan Leaf)

Post by Dala » 08. Jun 2020 08:04

HiTec wrote:
07. Jun 2020 22:22
Is that battery strap and the bolt aluminum?
No, that would create some galvanic reaction for sure. That picture was just for illustrative purposes.

I think the strap is stamped steel, that has been coated with something. The fastening on either side is a welded captive nut. The OEM bolts are steel with a black coating.

User avatar
Dala
SUPPORTER
SUPPORTER
Posts: 212
Joined: 14. Oct 2014 19:39
Location: Vaasa

Re: Dala's Leaf buildthread (2015 Nissan Leaf)

Post by Dala » 09. Jun 2020 21:11

So I thought this was very interesting. I was tasked with upgrading the battery on a 30kWh Leaf that had 255k km on the clock. That is a lot of km in a very short time. Check out the damage on this Leafspy screenshot
Image

So as you can see, there is a dip in the graph. This dip is half of the battery, more precisely the rear stack. This is the one that is prone to overheating, and after 3000x fastcharging events (WOW), the rear stack middle cells have taken some extreme capacity loss.

This car was only able to make it 80km before reporting itself as fully empty.
Image

After putting in a fresher and bigger 40kWh battery, things looked muuuuch better, and the vehicle is ready to cover another 255k km :)
Image

Very interesting to see that the Leaf otherwise holds up well so many km, it's just the batteries that are the weakpoint.
Image

User avatar
Sammyboi
SUPPORTER
SUPPORTER
Posts: 151
Joined: 01. Aug 2015 01:49
Location: Oulu

Re: Dala's Leaf buildthread (2015 Nissan Leaf)

Post by Sammyboi » 10. Jun 2020 09:34

That is definitely not bad concerning the lifeline estimate of an modern day ICE.

I'm just curious at what stage did the capacity loss become a nuisance. It must degrade slowly and not at once, so you just look at the estimate go down or does it deplete itself to an low number that you just have to do something?

User avatar
Dala
SUPPORTER
SUPPORTER
Posts: 212
Joined: 14. Oct 2014 19:39
Location: Vaasa

Re: Dala's Leaf buildthread (2015 Nissan Leaf)

Post by Dala » 10. Jun 2020 11:35

Sammyboi wrote:
10. Jun 2020 09:34
That is definitely not bad concerning the lifeline estimate of an modern day ICE.

I'm just curious at what stage did the capacity loss become a nuisance. It must degrade slowly and not at once, so you just look at the estimate go down or does it deplete itself to an low number that you just have to do something?
The capacity loss is gradual overtime, this was just an extreme example of the 30kWh pack that is more sensitive to heat. The many many quickcharging events every day is what made it degrade. It would still be usable for many years & km, but at the reduced 80-100km max range.

These batteries are quite stable normally and should last the life of the car. Especially the original 24kWh pack is very robust in our colder climates. Take a look at this

Image

That is a Leaf used as taxi, with 336tkm and 7151 Quickcharges! Taxi companies love these cars, since there is next to no maintenance on them. In the future we will see many million km Teslas and other EVs :)

User avatar
Dala
SUPPORTER
SUPPORTER
Posts: 212
Joined: 14. Oct 2014 19:39
Location: Vaasa

Re: Dala's Leaf buildthread (2015 Nissan Leaf)

Post by Dala » 24. Jun 2020 21:52

On another note, I launched a Patreon site last week. I'll be ramping up video productions! Already got the first tech-deep-dive video up on the site. The video will be released to the public in a few weeks, but if you feel like supporting my reverse engineering attempts I wont stop you :)

https://www.patreon.com/dala

The topic for the first video :)
Image

User avatar
Dala
SUPPORTER
SUPPORTER
Posts: 212
Joined: 14. Oct 2014 19:39
Location: Vaasa

Re: Dala's Leaf buildthread (2015 Nissan Leaf)

Post by Dala » 27. Jun 2020 09:06

The first video is now available to the public! :D

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest