Freelander 1 Wattson: Freelander EV Project

Hi Guys,
Been a while since I posted any updates to this project. I live in Kenya, so shipping parts in isn't easy especially during this Covid period.
Thought I update on parts I have received for this conversion:

1. Fully electric steering rack from a Honda Civic 2005



2. Tesla Gen 2 11KW charger
3. Tesla DC DC converter 2KW
4. Electric iBooster Brake from a Honda Civic 2018



5. Tesla small drive unit hack inverter control boards printed at JLCPCB courtesy of work done by D. Maguire and J. Huebner


Got a few other bits and pieces that will be used but not much can move until I get the batteries and drive unit, ETA end of May so I will update when those turn up or if any new developments happen.

Hi Guys!!!!
It has been a while since I updated here but in this part of the world, things move a tad bit slower.

After waiting for almost 9months, I finally got my Tesla Small rear-drive unit about a month ago.



I went straight in and started the inverter controller board swap to the OpenSoure inverter board design.
I will be honest, if getting the Tesla board off and custom board on requires precision. Lots of it.
These two current sensors are the most sensitive components I have ever worked with!



The old board removed and custom board installed.



Inverter put together and motor buttoned up.

Everything checks out from the motor 12V tests but I will not be able to do any high power tests until I build the battery pack.

I am using 8 48V 44Ah LG Chem modules for an initial 16KWh as a proof of concept as I figured not to invest heavily in batteries considering the price drop happening on used packs.

It's a shame that these two electric builds are on different continents. A Top Gear style series of challenges for the two machines when complete would be great.

Looking good @tensa4

Brilliant update Tensa4.
Looking forward to seeing the motor spinning

Fascinating to see these conversions. Looking forward to the results!

I'm loving the solutions and design decisions being made in this build, well done sir!

Hi Guys,
It's been over a year since I posted on this thread.
I have had to wait for over a year for Mouser to stock specific chips I needed to build the Battery management circuit boards using an open-source design hence the long delay on this project.
This has been resolved so figured I share updates on this project.

1. I received the BMS printed boards from JLC PCB in China based on the open-source BMS architecture by Zeva, the Australian master of EV conversion components. The company closed in September 2021 and made all its designs open-source. In October 2021, the following boards were made:
a) EVBMS: This will act as the brains of the system, a replacement for the ECU, and will tie all the EV parts together over CAN.


b) 24BMS: This is a 24S BMS board that will handle 24 cells in series. I only needed 4 of these so I made extras for resiliency.



c) EVMonitor: This acts as the display and input for the system. I get to see and set all parameters for the system here.



d) Current Sensor: This monitors the real-time current draw to be able to drive the tachometer and inform the EVBMS of how the battery is being used.

So after 1 year of waiting, in June 2022, Mouser finally delivered the missing chips required to complete the boards.



Spent the better part of last month completing the soldering of the PCBs and programming them.

The programming was the trickiest bit as I had to learn a bit about using AVR chips but succeeded in the end.



I got all the boards programmed and have run a couple of tests to make sure they function as required.

Next, I started on the battery tray



Then I test-fitted half of the battery pack,



All clearances checked out with all the pack tests mounted. With both halves in, it leaves enough space for a custom water cooling block that touches both sides of the cooling plates.

Next I connected some of the battery packs to the BMS boards and tested if the monitoring was working as intended.



Everything works as intended, so am now working to build the battery cooling plate before I move to connect all the batteries for a high voltage test run.

I also took some time to complete swapping the Tesla GEN 2 charger board and confirm the parameters for the same. The replacement control board was made off the open-source design by Damien Maguire and the guys over at OpenInverter







Next will be the high voltage tests once I finish putting the battery together.

I am really trying to really push to complete the project considering the delay I have had to deal with due to the Mouser chips/parts shortage.

Blinkin Heck.

Think I'll stick to building Airfix kits.

It's really great to see you back at this.
The work you're doing here is amazing, way, I mostly understand what you are doing but I couldn't do the soldering and would be terrified of damaging the Tesla gear so well done mate.
Just wondering tho have you confirmed the Inverter will run at 230V and continue to work when the cell voltages sag under load?

Alibro said:

It's really great to see you back at this.
The work you're doing here is amazing, way, I mostly understand what you are doing but I couldn't do the soldering and would be terrified of damaging the Tesla gear so well done mate.
Just wondering tho have you confirmed the Inverter will run at 230V and continue to work when the cell voltages sag under load?

Click to expand...

Thank you @Alibro I am also learning as I go.
The 230V was just to test the BMS system, the full system voltage will be 380V which should be sufficient.

tensa4 said:

Thank you @Alibro I am also learning as I go.
The 230V was just to test the BMS system, the full system voltage will be 380V which should be sufficient.

Click to expand...

Cool, it will probably be OK then. I tested my Nissan Leaf inverter at around 220V and it was fine.

Hi Everyone, it has been 4 months since I posted here but that is because I paused on the project to concentrate on work and some personal stuff.
I picked the project up a month ago and the following is a continuation of the progress on the build so far.

Having gained some ground on the electronics, I had stalled a bit because the car was still drivable, that was until the cooling system broke down on a long-distance trip and I decided to drop the ice.

Hi guys, I can not seem to be able to update this thread as I get the error "You do not have permission to view this page or perform this action" whenever I try to upload new photos of the project. Seems I am only allowed to post comments and replies only.
I reported a support ticket but have not got a response in two weeks.

Does anyone know who I can contact to get this resolved or do I just start another thread?

tensa4 said:

Hi guys, I can not seem to be able to update this thread as I get the error "You do not have permission to view this page or perform this action" whenever I try to upload new photos of the project. Seems I am only allowed to post comments and replies only.
I reported a support ticket but have not got a response in two weeks.

Does anyone know who I can contact to get this resolved or do I just start another thread?

Click to expand...

You will just join the list if you can "add a ticket". Its a known problem that has been affecting everyone since a site update.

If you are using a PC to post, you can copy images and paste them into a post. If your images are stored/hosted on the internet, you can use a link to them - depending on where you store them.