Project validation BMW E30 + Tesla SDU

[ElectricBMW]

Hi,

my name is Thomas...

and i have an empty shell of a BMW E30 and it would be a waste to throw away.
I thought about convertig it some years ago but it was way out of budget.

Times and prices have changed and i want to build it in the near future.

Getting the needed parts and building it is one thing.
Matching the electronics and software is a totaly different thing.

I am no programmer! And this will be my challenge in this project.
Aaaand the german TÜV.

So, my plan:
-Tesla rear SDU on the rear axle of the car with OI board.
(this should be the easy part)
-8-12 HV batterie modules in fitting locations with OI Flying ADC BMS.

First question: Can the OI BMS work with more than 8 modules? Or is 128 cells my max?
If so: is it wise to split battery modules to fill the BMS?


German TÜV:
TÜV Merkblatt 764 is my guide.
Apart from building a TÜV worthy car, there is safety.
I checked HV safety and Throttle safety so far.

One thing on my list is "Ready to Drive"-state and switching "Forward", "Neutral", "Rewerse".

-If i open a door it should switch to "Not Ready/Neutral", right?
-Switchig "Forward" or "Rewerse" should only be possible with Brake switch + Standstill?
I don´t want to hit Rewerse while going Forward and ruin a beautiful day.

This is it for my Newbe-Introduction.
I know there are many more checkmarks to set but above all is the TÜV-guy giving the "GO!"
And me, confident to start.

Thomas...
wishing a nice weekend

[Jack Bauer]

If it were me I'd use an M3 drive unit. Much better inverter but i am biased

[ElectricBMW]

I guess those are over my budget.
SDU + OI Bord+ OI BMS goes for under 2k.
Suitable batteries well under 10k.

[johu]

128 cells is way over SDU voltage. What's the plan there?

Yes direction switching is only possible below a settable speed

[ElectricBMW]

Hi Johannes,

nothing fancy. It will be a ~350V System. Maybe ~390V.

In one of your videos you said 8 BMS Modules is the max to chain together.
I don´t know what HV Battery i buy in the future. Some have 8 some have 12 Modules.

I´d like to have one BMS Module for each Battery Module. Just to have it clean.
But if you say it is overrated and 6 BMS Modules for 96 Cells in whatever configuration is good, i´ll do that. (i´d buy 8 anyway)

[ElectricBMW]

Figuring out Battery Options

I think a 12 Modul-setup would be the way to go in terms of fitment.
I can fit 8 in the enginebay and 4 in the fueltank location.
4 BMS in the front and 2 in the back.

VAG battery modules (ID4 or e-Tron) would be 300kg.
200kg in front
100kg in back + 90kg Motor

Front weight cancels out nicely and rear needs some work.
Overall nice ballance and ~82kwh.