Finishing up the brake lines
The batteries now all have a place to live.
https://youtu.be/3bqqs1FmUuc
Time for more wiring!
BMS wiring
https://youtu.be/Agkct0mlJ_E
BMS wiring continues
https://youtu.be/l0EmqIkPM0Y
It's Alive!!!
https://youtu.be/uOTiEmnUNQw
Trouble with the second battery pack
https://youtu.be/3TUlZvarS5A
Taking a break from electrical to paint calipers
https://youtu.be/wQZ3pK5FlKg
DIY aftermarket electronic parking brake. Still having troubles with pack 2.
https://youtu.be/Ci8IeDyotfs
Hey just got caught up on your build, glad to see you're actually using 192 battery cells rather than 12, they're similar in size to the ones used on the Porsche Taycan so they're not unusually massive for EV cells.
But I noticed you're making a serious mistake in the structural design of your battery packs, and you might be making some mistakes in the design of your cooling system.
Generally your battery packs don't have enough lateral support - they should have just as much lateral bracing as there is bracing to keep them from moving fore/aft, but you consistently use much less. Your batteries should stay in the car if it were stood up on its nose or tail or put on its side, since your car will be braking and cornering at around 1G (and possibly accelerating as hard too). And that's without even getting into extra support you might want in case of a crash.
Another potential structural problem is the amount of physical pressure the modules might see and possible need for room for expansion. You need to check on this - cells often need room to expand, if they don't have it they can pressurize themselves when they expand with heat and then catch fire like the Samsung Galaxy Note 7. And because the modules aren't all individually mounted to the pack case, you'll have to check on how much weight they can take - for example in a 1G corner, the module at the outside end of your front pack will have the weight of 2 other modules plus cooling plates pressing on it, and those modules might've expanded a bit from heat too.
Next, potential cooling problems. It looks like you've got each battery module attached to a cooling plate on only one side, are you sure this will get enough heat out of the modules? The OEMs, when they use cooling plates, usually have one layer of modules (with each module containing 1 or 2 layers of cells, it looks like your modules have 2 layers) sandwiched between cooling plates on both sides.
Another potential problem is the Tesla S motor+inverter+diff unit being tied into the rest of the cooling system like any other water-cooled component. As you know the S motor has heat problems, and if it's simply plumbed in with everything else then that heat problem is shared with all the other components, which in turn makes the motor overheat even more easily. If you want better cooling, you could have a radiator at the output of the S powertrain so that the hot fluid from it is cooled before joining the rest of the system, or you could even give it its own separate cooling system.
Edit: Also, as to charge port location, I'd recommend putting it at the front of the car, most EVs have their ports there and public EV chargers are usually positioned at the end of a parking space such that plugging into the car's nose would be most convenient.
I got a bit of spam the other day that made me thing of this project and wonder if its any interest to you
AEM is a decent size play in the race car electronics space (my ECU had an AEM badge but not their software in it) and it looks like they've decided to bring iot to the electric space.
In reply to mke :
Hmm...definately interesting. I will have to do some additional research. Thanks for sharing.
Brakes are finished! Getting so close to the first drive.
https://youtu.be/8jZZW74rBpo
mke said:I got a bit of spam the other day that made me thing of this project and wonder if its any interest to you
AEM is a decent size play in the race car electronics space (my ECU had an AEM badge but not their software in it) and it looks like they've decided to bring iot to the electric space.
I’ve been following this with some interest too, as I’d like to do an EV conversion of my own some day, and this looks like it’ll make things more plug-and-play. There seems to be precious little info about the controller, and my guess is that the Coronavirus situation will only delay it further sadly. I thought this write up from PRI was pretty helpful though:
The car in their booth is using a lot of Cascadia Motion gear (BorgWarner motors) but I imagine they’d also support a Tesla drivetrain as well. Looks like a solid option for the future!
ElectricSuperCar said:Brakes are finished! Getting so close to the first drive.
I’ve been following with some interest both here and on YouTube. This is an awesome project so far, and I can’t wait to see how it goes down the road. Props!
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