I’m not sure about anybody else but if the price of the board is already gonna be 3k+ I think either 12s12p of 30Q or if you could maybe 12s9p of. 40T
IIRC The main benefit of 21700 cells is that they are good for single-stack batteries, because their thickness is less than a double-stack of 18650s. With P-groups this high, size constraints like that are gone, so 30Q would be better because they are king.
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8P of 21700 would be the max, because of the single layer configuration. The height of the enclosure would be 1,5cm thinner compared to the double layer 18650 stack.
esk8 uses high discharge cells like 30q and 40t because we require it.
At 12p levels, unless you are planning to draw 240a battery amps continuous, using 30Q’s are a waste.
You can get cheaper and/or higher capacity brand cells that have a max discharge of 10a per cell and still come out with 120a continuous. Or 15a per cell and have 180a continuous
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Yes, 30Q are rated at 15A and we are aiming ~200A possible continuous discharge, even if it never will be happen in real world.
Not really trying to bash you here, but it looks like some of this seems like a case of “just because you can doesn’t mean you should”… like why ceramic bearings? everyone knows these are a bit of a con…
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We do it do show what’s possible on an electric skateboard. Some people like to know, that their hardware is capable of more than they are. It is reassuring to know, that you are not bottlenecked by your components.
What is your opinion about ceramic bearings? Obviously not everyone knows what you know. Please feel free to share with us your thoughts and experiences. 
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Bearings get quite the discussion on the cycle forums, but here is a nice vid with some hard figures to demonstrate
anyway the short of it is that ceramic is best for high rpm, clean, low load environments like drone propellers and really not good for transport purposes
If you want top notch bearings to handle some abuse use Enduro Bearings (https://www.bike24.de/p1174525.html)
Otherwise just any other quality SKF NSK 2RS sealed one. Whatever friction benefit you get from a ceramic bearing you will loose in your drivetrain belts etc.
Good ceramic bearings are just über expensive (look for Ceramicspeed ones)
In my opinion expensive low friction bearings are stupid in electrified setups. Better have some robust ones with good seals an thick grease.
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Keep me updated for your rides next year I want to ride with you guys , greets from bavaria
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Thanks for the video. It was interesting to such profund tests.
I want to tell you a little bit about the background story why we decided to go for ceramic bearings. Last summer when we started testing parts for the Project X, we all rode just ceramic bearings, since they are coming stock on the Evolve GTRs. We soon started to experiment with different wheel und gear setups. Some of that new wheels had steal bearings inside. During our high speed test on a hot day, we experienced a blocking wheel on one of our skateboards. The reason for the blocking was the bearing. It got so hot that the steel balls got welded together.
I don’d know how it could happen. Either from the lack of enough lube or from some filth that got inside and caused too much friction, but the result was that we never experienced such a problem with ceramic bearings.
We don’t want to use ceramic bearings for the reason of saving one or two Watts, anyway we have 10k of them. The reason for ceramic bearings for us is, to provide such scenarios.
The thing with the lower friction with oil vs. grease and the lack of the protective sealing from the video may be true for the first 100km. But how does it look on longer distances?
- Grease lubes the bearings for longer time than oil. It stays longer in place and doesn’t dry out that fast.
- If you remove the protective sealing you may have 0.1% less friction on the first kms, but after a while dirt will get into the bearings and will cause a lot more friction that you saved before.
And keep in mind the tests were done with bikes going 35km/h. We will reach speeds twice as fast with bearings way lower to the ground.
Besides that ceramic bearings are more water resistent than steal bearings. So, on long term I think sealed ceramic bearings will work best on an electric skateboard with low maintenance.
But we all have to keep in mind, that not all ceramic bearings are the same as not all steal bearings are the same. We testest for example Lazyrolling ABEC 9 steal bearings vs. Zealous ceramic bearings (the white ones) and finde that the Lazyrolling have less inner friction and role indeed better than the Zealous.
So when we will find very good steal bearings that will fully fit our requirements, may be we’ll go with high quality steal bearings. But so far ceramic is our best choice.
That’s the reason why we like to test everything on ourselves and don’t rely only on youtube videos and random forum posts.
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Well it’s good to see you’re testing a lot of these things 
maybe at some point you can share some for your results? As a fair number of components we use aren’t really specifically designed for the way we use them so it’ll be good to see what comes out…
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Great to have you back! 
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We want to test some 7KW 80100 motors.
What supplier you want to see Maytech, Flipsky, APS, or something else? Must be sensored thoug.
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Do you have mounts that will have the bolt pattern of a 80100 motor?
We can build them.
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I would go maytech then.
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Ive heard the new batch of flipsky motors are pretty good (but would probably source from HGLRC if you can) but maytech motors are solid since their larger motors get sizeable bearings to support the stator and if you battle harden them they’re indestructable. Only heard bad things about APS motors.