[WIP] Audi A2 refreshing an old conversion

[Pieter]

Hi all,

I am refreshing an Audi A2 wich has been converted to electric in 2012.
It currently has the following components

• Akoe 132 motor nominal 28kw max 40 kw. mated to the original gearbox.
• DMC PAC950TL01 AC Traction Controller.
• 30s lifepo4 180ah battery pack 108V
• emus bms
• zivan charger
• victron dc/dc converter

The previous owner who bought it from an auction in germany depleted the battery completely on his first drive.
The batteries now seem to be dead reading really low voltages.

I had seen some success from other forum users with the opel corsa e / peugeot 208 battery pack (thank you all for documenting).
I have decided on using those battery modules.
Using four of them in series would give me a 24s battery pack. This would work nicely with the existing charger motor controller etc. I am planning to eventually install several 24s packs each with there own bms and contactors.

[Pieter]

After removing all lifepo4 cells I got the car moving on 4 opel corsa modules https://youtu.be/YooQENT02AY.
I decided to remove the old diesel tank and create another battery box underneath the rear seats. I will place 4 of the 16 modules in the new box and there should be enough space left to place all contactors, bms and charger.

I'm using the existing bms boards in the modules to read out cell voltages and for balancing. I recently got the communication working with clanarn's pcb. see viewtopic.php?t=2181.

[EV_Builder]

Nice! Follow!

[arber333]

I have the same AKOE 132 motor but i had it rewired from 72Vrms to 180Vrms and it runs really good at 320Vdc battery and openinverter.
Its real problem is overheating on the highway and its huge starting torque wich requires 3Hz startslip.
I have had to remove the cutch and install the lovejoy coupling because clutch was getting destroyed.
How do you connect motor to transmission?

With a good battery i could get 80kW into the motor

[Pieter]

thanks for the nice responses.
This is a bit of catch up post.

Front battery box.
The front box is mounted underneath the back seats as I posted about before. There are nuts welded on the bottom for mounting the batteries.
it is glued and screwed in there with automotive window caulk.

Batteries
The batteries are bolted to the battery boxes with M8 all thread. I designed some plates that go between the rods to stiffen it up.

BMS
The battery modules have built in bms functionality. I decided to design a main board for this bms system based on stm32 and max17841b.
Because the battery pack consists of four parallel strings of four modules I want to monitor the current flowing through each path. So my bms main board was designed to read out four Tamura L03S600D15. The board also has 8 drv103 contactor driving circuits on there to be able to fully isolate the four parallel packs. This board definitely needs a V2 and possibly more but it is in some sort of working state. I wrote some code for it to check if everything is safe and close the contactors.

Current events
The car can now move under its own power again with all modules in the car.
I am in the process of designing a BMS main V2.
Meanwhile I went to test the charger that came with the car. It is a Zivan NG3 charger.
This charger is giving an error(red green flashing). I have to look further into that.
Does anyone know the can protocol it is using? because it was hooked up to the last bms with a can connection.
Other ideas for charging solutions are also welcome.
The battery pack consists of four 24s packs in parallel so the max voltage is around 100V.

[arber333]

I remember there is a page for various charger CAN telegrams. Zivan SG3 charger is among them. Maybe NG3 uses the same protocil. It would be logical... https://lithiumate.elithion.com/php/con ... _specs.php

https://www.kit-elec-shop.com/gb/lithiu ... ttery.html
https://www.kit-elec-shop.com/gb/index. ... chment=985