Whats the expected price of these going to be? Do you need any beta testers?
The BOM is looking at this moment roughly about 60ā¬ for a single main module and about 34ā¬ for a batch of 100, but once I get the HW design tested and locked down I can move onto larger build batches, which will lower the component costs. Iāll have to later look into if it makes more sense to fabricate and and furniture the boards with a third party, or whether to build them in my own space.
I also donāt mind selling just the PCBs (+ possibly components) to those who want to assemble their own boards with the BOM available on github. Honestly I donāt want to nail down the price point to stone at this point in time, but I wouldnāt expect less than 70ā¬ once all the costs have been included.
I will most likely need/want at some point, once the module makes it through my own performance tests and I fix any obvious HW mistakes. Once that time comes I will inform about it in this thread and open up some kind of application form for a limited amount of people. Modules might be provided free of charge, except for shipping and once the beta ends I will either let participants keep their modules for free-of-charge or pay for it with a discounted price for their help and effort.
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Hello there, Iām late and havenāt read the thread completely yet but Ivam very interested if the footprint is this size & it does 12s, discharge protection, anti spark & eswitch can I get in on 1 or 2?
I will read the thread later when I have time thanks for your efforts in producing this
Sorry, the OP is not up to date with the current state of the project. Iāll update it today, so it is up-to-date and new thread readers can more quickly understand what is being designed.
I would recommend starting to read from http://www.electric-skateboard.builders/t/flexibms-first-prototype-kicad-project-files-released-flexible-configuration-and-charging-bms/46117/23
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sounds awesome - canĀ“t wait to test one 
Thanks for the pointers, definitely want a split board here even better a stacked sandwich, I may try to make one or two.
Edit: I get it all now, the bms part is fully designed then we have the option on the switch side of the bosrd to size to discharge amps required, wonder what a pcb of the same size footprint could handle amps wise, also convenience to quickly swap out the switch board innovation 
So at last whatās up with this project? is there some demo vid of it somewhere?
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PCBs are being manufactured at the moment.
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Hopefully this project will succeed.
What would be the price for a 12S around 80A BMS setup?
and how flat would it be?
This project is just beginning and is in prototype stage. I donāt want to start promising any price points yet, because we havenāt even tested the first prototype, whichās PCBs are at the moment being manufactured. Iāll be updating this thread as progress happens.
for more info, refer to this post at this point: http://www.electric-skateboard.builders/t/flexibms-first-prototype-kicad-project-files-released-flexible-configuration-and-charging-bms/46117/162
These prices look fine if you can ensure the quality over long period of time. Book marked.
Update.
Components ordered at the beginning of week and have now arrived.
PCBs are in the country and if lucky Iāll be able to get them tomorrow, so Iāll be able to assemble the first board and do basic functionality checks on it during this weekend.
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Boards are here! Iām going to work on these during the weekend and try to progress towards functional prototype. No component has been soldered yet to the boards in the pictures, I was just placing the bigger components.
The balance circuitry is very dense (as I designed it), I guess Iāl just have to try and solder the components on or cry and solder them on 
Here is the size difference to the old pre-alpha prototype board, and as cliche as it might sound, I thought to myself āoh wow, this board is pretty smallā when I got it out of the packaging.
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Nice is there rosin in your tears? 
I lick and scratch pine trees in the morning for my natural daily rosin dose.
Or if Iām about to crash, I go straight for the good stuff.
EDIT: Itās a joke. Just in case somebody doesnāt know or understand the context.
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Haha good oneā¦pine fresh
for the xt90 connectorā¦just to let you know that there is a new type (already sold but not yet published) from Amassā¦perfect for PCB.let me know if you need the .stp fileā¦cannot upload it hereā¦
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Thanks for the tip!
Iāll look into this once I start designing the Switch-module.
Board is assembled. Havenāt tried to hello world the MCU yet, but thatāll probably be the first thing tomorrow morning.
There was a one major layout goof with the board. The footprint for the LTC6803-3 was incorrect with the wrong specific SSOP-package. The actual IC package was longer and wider than the footprint, but with the same pin pitch, so I managed to squeeze some of the components at the end just a bit further away and then bent the pins on the IC under it, enabling me to still solder it onto the board, although I wouldnāt subject it to a lot of vibration with the fear of some of the solder points breaking loose.
Provided that everything is otherwise working on the board I can start testing and writing code for it. The layout will go into new iteration soon, which I have some improvements in mind and Iām gonna look into putting in the CAN-support as well.
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What if you trim the pins? Seems like enough pad beyond the ic