[WIP] VW Manx conversion

[tom91]

could someone please point me in the right direction which BMS system is suitable for me

This really depends on what you feel comfortable with. I developed the SimpBMS which is fully opensource https://github.com/Tom-evnut/BMWPhevBMS
Unfortunately due to the stopping of making of the Teensy 3.2 chips i have had to fully redesign it and improve it into a more commercial product which is the EVS-BMS, which is available through my webstore.

Besides that others have taken the code and ported it to other devices like the ESP32 https://github.com/bookofthefuture/BMWPhevBMS-ESP32

These options can all work with the ZombieVerter under the option "SimpBMS"

[Sjanders]

Have you watched Greg's video's yet? Proper deep dive into the packs:

Hi Marcexec, thank you for your message! Yes I did check Greg's vids, very informative! In fact, his vids gave me enough confidence that I would be able to tear down a pack an use it in my own project. I did check out his vid where he used SimpBMS on a Teensy 3.2, but I haven't seen one where he elaborates on cell balancing and how SimpBMS is controlling the charging sequence. But maybe I missed that vid

Cheers

[Sjanders]

This really depends on what you feel comfortable with. I developed the SimpBMS which is fully opensource https://github.com/Tom-evnut/BMWPhevBMS
Unfortunately due to the stopping of making of the Teensy 3.2 chips i have had to fully redesign it and improve it into a more commercial product which is the EVS-BMS, which is available through my webstore.

Besides that others have taken the code and ported it to other devices like the ESP32 https://github.com/bookofthefuture/BMWPhevBMS-ESP32

These options can all work with the ZombieVerter under the option "SimpBMS"

Thanks Tom, I've screened through the EVS product manual on the EVS-BMS. The document gives me a better understanding how things can be done. I will read some more to get a full picture.

Thanks!
Sander

[tom91]

The SimpBMS protocol as per the SimpBMS derived solutions and EVS-BMS can talk with the Zombie then the Zombie can do contactors and charging handling.

You are in the Netherlands, how are you getting your build road legal?

[Sjanders]

Hi Tom,

Thanks again, that sounds what i need! Great!

Road legal...yeah that is a bit of a race against the clock. Previously you could convert your car and have it checked by the authorities, when you get their blessing the conversion is the approved and legal. But...some rules might change halfway 2025 which forces a conversion to use an approved battery pack, or that one develops a pack that needs to be approved, which might need destructive tests...

I will try to get the build finished a.s.a.p. in order to avoid the new rules. Hopefully I'm fast enough. Alternatively I will strap the full BMW pack on the roof of the car

Cheers!

[Sjanders]

Hey,

Today I've doing some measurements on the BMW battery modules and how I could fit the in the buggy. Initially I was thinking about a split battery pack, so 4 modules in the front and 2 in the back for space an weight distribution. But it comes with additional complexity and costs so I skipped that idea.

The plan for now is to place the modules on theire side back to back (or original bottom to original bottom) and instal a heat exchanger in between them. Like so:

This will fit nicely right above the rear torsion bars. Other configurations of all modules in a single pack doesn't fit. I do need to find a solution to connect the modules in series, maybe I can find a way to make som bus bars instead of using the original cables.

Then for the battery box, as I would like to keep the weight down as much as possible, my idea now is to build a carbon fiber (CF) battery box. Does anyone have experience with carbons fiber battery boxes? I've seen manufacturers use CF as battery box, in addition, some existing boxes have plastic covers, so the use of some sort of plastic or polymer is not new.

The idea for my box is to incorporate stainless steel mounting points for the heat exchangers and battery modules into the CF.

Any ideas on this matter?

Thanks!

[jrbe]

Carbon is conductive so any hardware should be isolated to prevent corrosion. It's also strong but brittle. You can add in some kevlar to help out some.

You could do a balsa core box and layer carbon then fibreglass on the inside. A thin layer of fiberglass can help insulate and also protect the carbon.

But you should practice a lot before making a battery box and make sure you've got things right for strength and a good lifetime.

Aluminum is likely your best bet. There's always carbon look vinyl film.

[nkiernan]

The plan for now is to place the modules on theire side back to back (or original bottom to original bottom) and instal a heat exchanger in between them. Like so:

Is it ok to mount these modules on their side? Not all HV modules can be orientated this way

[Sjanders]

Is it ok to mount these modules on their side? Not all HV modules can be orientated this way

I'm only copying others ideas and experiences

Arturk has done a really nice Jag conversion: https://www.youtube.com/watch?v=8RAvX9RylRU&t=399s. Around 5:30 min in the video. This build uses modules upside down and on their sides.

Gregski is also building a pack with half the modules upside down i believe: https://www.youtube.com/watch?v=K60pgbxBZoo.

But to give you an honest answer, I don't know if it's ok....

Edit: I will, of course, take special care to mechanical support of the modules to avoid deformation under stress.

Cheers!

[Sjanders]

Hey all,

I decided to buy an ESP32 dev board and try out SimpBMS software for my BMW battery modules. I used this earlier ported ESP32 code: https://github.com/bookofthefuture/BMWPhevBMS-ESP32. At this moment the ESP Arduino core is at version 3.1.1. I tried to compile the code but ran into some issues with the watchdog timer, after (apparently) solving that issue I ran in to a hole bunch of other issues.

After some more reading I found that there were some major changes from version 2.x to 3.0. Having very little (I mean barely non) experience with programming I was wondering the following:

Has any created a working code for ESP version 3.1.1? If not, at which version has the code proofed to be working?

Many thanks!

BR Sander

[Sjanders]

Hey all,

A small update on my last post:

I've tried out several combinations of board manager versions and library versions and I was able to compile and upload SimpBMS to my ESP32 board. Using library ACAN_ESP32 version 1.1.2 in combination with board manager esp32 version 2.0.11 (all other libraries use the most up to date versions) worked.

But now a new thing to solve has surfaced...it seems that the SPIFFS (Serial Peripheral Interface Flash File System) causes problems.

Code: Select all

Resetting to factory defaults
E (4025) SPIFFS: mount failed, -10025
E (14364) task_wdt: Task watchdog got triggered. The following tasks did not reset the watchdog in time:
E (14364) task_wdt:  - loopTask (CPU 1)
E (14364) task_wdt: Tasks currently running:
E (14364) task_wdt: CPU 0: ipc0
E (14364) task_wdt: CPU 1: IDLE
E (14364) task_wdt: Aborting.

abort() was called at PC 0x400f1f91 on core 0


Backtrace: 0x40083835:0x3ffbec5c |<-CORRUPTED

I've tried several different partition schemes, until now non have been successful. Any one got an idea how to proceed?

Thanks!

[Sjanders]

Hey all,

Another update: so, after checking everything from the ground up I found that I failed installing the right Async TCP library in Arduino IDE. After installing the right one I updated the board manager (ESP32 3.1.1) to the most up to date version and compiled and uploaded everything. After changing the watchdog timer code the serial monitor finally started to spit out something that wasn't related to the previous self caused problems. At this point the error messages were related to the fact I had no CAN transceiver and battery modules connected.

So at this point good progress. Next up: hooking up the BMW modules and learn some new things!

Cheers!

[Sjanders]

Hey all,

So, after spending some time trying to get SimpBMS running on a ESP32 I decided to put that aside and start testing all my components chained together to see if I was able to get a "first motor spin". Previously I tested all components separately using Zombieverter v2.17, that all worked out well. Recently I flashed to v2.20 and some things behaved a little different from what I knew, after a super fast Q&A here on the forum (Thanks Mitchy and Tom) things we're clarified.

For the first spin I hooked up 4 BMW modules (I understood the Outlander rear inverter requires minimum 200V to operate) to the S-BOX and from there is was really easy peasy lemon sqeezy! With the initial tries, the throttle actions gave a kinda choppy motor behavior, but after some modifications of the REGENRPM and THROTRAMP the behaviour was really smooth!

Trust me, I know what all wires are for

Next step in the process: test the Outlander charger. I the mean time I will continue the mechanical side of the build.

Cheers!

[tom91]

test the Outlander charger.

Sure but id wait a bit, I did clean ups in the code to get it working more nicely using proximity detect.

[Sjanders]

Sure but id wait a bit, I did clean ups in the code to get it working more nicely using proximity detect.

Thanks for the heads-up Tom! Enough work to do so that subject can wait!

Do you have an indication on the release date for that code?

Thanks!

[tom91]

Do you have an indication on the release date for that code?

No its not on me to release. I can provide you access to the "Testing branch" when we get to it. You started to document your wiring be good to work on getting something drawn up. This I would say is an ideal "starting" project with readily available parts.

[Sjanders]

No its not on me to release. I can provide you access to the "Testing branch" when we get to it. You started to document your wiring be good to work on getting something drawn up. This I would say is an ideal "starting" project with readily available parts.

Right, I see! When I'm up to it i'll let you know!

And indeed, I experience this as a decent starter project with lots of available parts and of course loads of information and knowledgeable people on this forum.

Cheers!

[Sjanders]

Hey electron heads!

Today I did some minor work on the conversion project, a bit of motor alignment and measurements for some laser cut brackets.

I also test fitted the Outlander inverter and after trying serveral locations this seemed to be the most logical one, other positions were to close to the wheels for my liking. Especially since the back of the buggy is totally open and water can splash around freely on wet roads.

Unfortunately the cable (part #9499D147) motor and inverter is now to short. Preferably I'd like to build a new cable using the original cable connectors/clamps. I tried to disassemble the original connector, by gently tapping the plastic part I was able to remove it's metal housing. Unfortunately, some of the plastic broke during the process, the plastic is really brittle!

So, the idea at this point is to reuse the plastic part, preferably I'd like to buy a fresh new part, and build a longer motor cable. Here on the forum I saw 3D printed parts as an alternative to connect a cable to the motor/inverter, but I'd like to stick to the original connector if possible.

Does any one know if this plastic connector part is available from a dealer of after martket supplier?

Thanks!