openinverter forum

Hello! I want to introduce my project which I started a couple months ago. The donor car is a 2001 BMW e46 320d with 110k km.
EDIT:

Parts that are going in

Motor: Leaf gen2
Inverter: Leaf gen2
Battery: 52Kwh ZOE. 10 of 12 modules = 43kwh
BMS: MAX17823B or BMW X5 slaves.
Brake booster: Tesla model 3 ibooster
Steering: Original rack with TRW hydraulic pump
Veichle Control board: DIY
Charger: Mitsubishi Outlander OBD/DCDC

Here is a picture of the car before hauling it to my garage.
Picked up a 2015 Nissan Leaf motor, gearbox, inverter, charger/dcdc and AC compressor on a junk yard close to Oslo, Norway. Used EV parts in Norway is much cheaper than in Sweden . I managed to split the leaf stack into motor+gearbox and inverter+dcdc so we could lift it by hand into the trunk.
Removing the engine and transmission.

Test fitting the em57 to see if it clears the steering rack. I made an adapter plate out of plywood and attached it to the original 5 speed manual gearbox . The inverter fits great also leaving room for the rear facing cooling line. The dc/dc&charger does not fit on top.

Moving on to building the actual adapter plate. I ended up using half of the gearbox/differential casting. This enabled a thinner adapter plate (12mm aluminum) and not having to cut away the inverter mount above the phase connectors. Other than that the process was sort of similar to Damiens way of doing on his Grey Goose.

Marking up the plate with the outer gearbox casting. Left is leaf side and right is from the bmw clutch. Welded together. Finding a "silent spot" while spinning the motor with Arduino and can interface.

Time for an update=). Starting with battery.

I live in Sweden. EV batteries are 50-100% more expensive here than in Norway. However due to covid restrictions I couldn't travel there for like 6 months. So that sucked. Anyway I ended up purchasing a 2021 Renault Zoe battery for a good price. 52kwh. Consisting of 12 8s modules. 4450wh each. I will be using 6 in the front 4 in the rear. 80s will be sufficient for the leaf inverter. reusing the battery tray. Going in something like this. Fits just barely. More on the battery box later. BMS is based on MAX17823B. I am maybe going to try to make a master board. Bexander here on the forum has already made it work. Awesome! viewtopic.php?f=26&t=1179

Neat idea using half the gear box because you reuse even more material. My version looks more home made and costs a little extra viewtopic.php?p=1105#p1105

Yea im pretty happy with that solution. Not sure if the spline adapter will work however. I have a lathe now so I can make it a bit more balanced atleast. Shouldn't hurt=). If the transmission breaks Ill go with a coupler instead.

Shielded 35mm2 ÖLFLEX running from the trunk to the front. I am a bit concerned however that it will interfere with CAN bus wires that runs along for like 3 metres. Does anyone have any experience with this?

Amphenol SurLok Plus™ EMI connector in the making. This connects to the contactor assembly and I think it will be going in and out a couple of times. I like to build stuff that is easy to disassemble.

Charge port assembly. J1772. Two 3d printed parts that presses the assembly, holding it together with 4 bolts. Thus no need to weld or drill into the car.

Contactors and precharge built on to a 12mm plastic board. Drops right onto the leaf inverter. By placing connectors and wires on the bottom of this I can make a very simple lid and keep it waterproof. Think I will make it in fiberglass or carbon.

Clanarn wrote: ↑Tue Sep 28, 2021 8:09 am Shielded 35mm2 ÖLFLEX running from the trunk to the front. I am a bit concerned however that it will interfere with CAN bus wires that runs along for like 3 metres. Does anyone have any experience with this?

Having CAN and HV close to each other in the exhaust tunnel didn't work for me. CAN was shielded, HV was not though.
I relocated the CAN bus about 30 cm away, then all was well.

Will you have any fast charge port?

Interesting. Have to think of a way to test drive and put some load on the cables to see if it works before cutting them into lengths then. Hopefully the fact that they are shielded makes a difference. I could probably ground them in a shorter intervals with P-clips or even wrap them into copper mesh if its not sufficient.

Yes. The outer contactors as seen in my previous post is for chademo. I have an outlet that I got with the leaf inverter/motor I will try to integrate behind the kidneys.

Made a fiberglass lid for the contactors. Should look nice after gelcoat and paint.

First time ordering from JLC-pcb and it actually works yeyyy. Nothing fancy but it will do the job. It consist of
- Teensy 4.0
- ULN2003 for driving relays and to pwm stuff.
- Charge interlock. Inverter doesn't get power if charger is plugged in.
- Relays for main contactors and water pump.
- fuses
- digital inputs.
- Analog in for the throttle.
- 2x CAN

Its purpose is to control the leaf inverter with CAN, switch the contactors, control cooling pump, communicate with the cars dash and communicate with a charge/bms board I'm working with right now.

Watercut. Welding battery mount.

2 layers here. 3 batteries in each layer.
6*4.5kwh=27kwh
Yes, that's only in the front.
Pretty tight however. The modules wouldn't fit in this config if they were 1cm longer.

Building busbars. Zoe service disconnect and radsok connectors. All mounted on an alu plate so that the box can be dropped down onto it. Busbars from the bottom row. I will add a bit more isolating protection here.

Next step is also to build a box around this with 0.8mm stainless sheet. It will be welded together and then dropped down on the pack. Plan b is to use rivets.

Here I'm TIG welding the box. Was just as hard as I expected to be. Should be strong enough but not waterproof. Therefore I'm thinking of adding something along the weld to seal it. JB weld or butyl seal tape.

I have used what's called "karosserikitt" in my battery box. I think it is called automotive seam sealer in English?
https://www.jula.se/catalog/bil-och-gar ... cm-623110/

Just what I was looking for! Will try this. Is it possible to sand it?

I have not tried sanding it but it might be difficult as it retains some flexibility even after it is cured. You can shape it quite well with your fingers or other tools when you apply it.

Update time. Finally sort of finished the front battery thus making room in the garage for the car. Rather nicer to work on the car in 15°C vs -5 . The rivets need to be waterproofed and I think I will make an extra support under the battery.

BMS in development. Bexander has helped me design an interface board with MAX17841. With 2.54mm headers it can be used on a breadboard for testing and then soldered on to a dedicated pcb for example. More info on this when I get it up on GitHub. Contact me if you are interested to purchase a board.