How do you plan to build the battery to allow for 525A output? Or more like 400A if you say you want 20kw constant.
This isn’t an esk8 any longer, but an electric car whereby you stand on the roof.
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You’ll see, you’ll all see…
The new battery layout actually allows for full connection between series groups. Every cell can have 2 nickel strips to the next cell in the next series group.
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Sometimes reasonable men must do unreasonable things.
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fixed your type-o
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Keep going my friend 
Loving this 
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If you compare 40T to 50E:
If you compare the batteries at Lygte.info you can se that 50E sag the same amount of volt at 10A as 40T in 20A, almost same at 15A VS 30A.
https://lygte-info.dk/review/batteries2012/Common18650comparator.php
40T:
Cont: 20A15P=300 A (300A45 V = 13.5kW)
Peak: 30A15P=450 A (450A45 V = 20.25kW)
50E:
Cont: 10A15P=150 A (150A45 V = 6.25 kW)
Peak: 15A*15P=225 A (225A * 45V = 10,12kW)
I pick 45 volts since batteries sag some and you dont run max volt all the time.
Good luck staying on the board at 20 kW if you get the power down in to the ground.
Saying same as Kaly, Loving this
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What a beast! Totally in love 
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Yes and for this reason is why I couldn’t go with the 50e cell even at 15p. I’ve also read somewhere that cels with higher discharge ratings tend to be able to be cycled longer but I’m not 100% sure about that… (longer useable life cycle)
Edit: this may be indirectly attributed to cells with higher amp output not being used to their full current ability which results in a longer life span… I’d rather use 50-60% of a cells current rating as opposed to 90% of another cells rating
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I think you are on to something here and it is more applicable to smaller packs since average load will be higher per cell. I read somewhere that peak load for like 5-10sec is not so bad for the cells. But continuous load near cell max Amp limit will lower the cell life span.
Lets see here 12s15p with your 4x80100 motors and mudpluggers.
I would guess that it will pull average 40Wh/km but lets say 50Wh/km to have some margin and lets say you average 40 km/h which is high to average i think with 9" muddpluggers
The range of your board at that load should then be 2600Wh / 50Wh/km = 52 km
50Wh/km * 40 km/h = 2000W
2000W / 15 cells / 45 volts = about 3A / cell.
I believe that 3A/cell average load is not much even for 50E cells.
But lets say it would have 20 % lower lifespan than 40T.
40T has about 80% Wh of 50E.
Lets estimate if you charge your 40T to 100% every time and after 500 charges you got 80% wh left.
26000,8= 2080 wh
Lets estimate if you charge 50E to 100% every time and after 500 charges you have 64% wh left.
32400.64= 2070 wh
Then the lifespan of your battery before it is at 80% would be 52 km * 500 cycles = 25000 km. (I think you will have longer range and longer lifespan than that)
I only want to say that I really like that you took 40T cells so you can really get out high peak AMP without high voltage sag for this crazy setup!
I think that it is good to consider this when building a pack for a board.
I was running 2x6374 149 kv, 1:4 geardrive and 50 psi 8" trampa striker last summer (65kg rider) and had an average of 12.9 Wh/km
Average speed was about 30 km/h road and dirt riding.
12.9 Wh/km * 30km/h = 387W
I have a 12s7p 30Q but think now that 35E would be better for this setup since
387W / 45V / 7p = 1.22 A/cell
I peak 105A from the battery with 2x80A on the motors
I think 35E can handle peak of 15A*7p = 105A
This is my thoughts on lifespan and i read that it is best to use the battery between 25-75% charge to get the longest so that is typically what i am doing when i am not going for a very long run.
There are a lot of test with same current during full cycle but very few with a lot of peak loads and peak recharges which we are doing when running. One thing that is happening during high current continuous load is that it heats up the battery which do not happen at even near the same extent at peak loads.
Hope i did not write to much, read if you want and reflect. Good night
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Hey man! Thanks for your analysis
The above number is accurate but doesn’t reflect the full story. Although I may be pulling only 2,000 w while riding at 40km/hr that doesn’t reflect the full numbers that I plan to achieve. I am building this board to handle a constant power use of 20,000w and up to 30,000 w peak. I’m looking for a world record my friend. I’m thinking… semi truck tow.
I am happy with my cell choice of the 40t. That’s what the math says
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UPDATE: I am going with the Hoyt St Midnight puck for my controller.
I chose it for the different control modes, outstanding rider reviews, thumb throttle for precise control, grip tape on the controller (super grippy) , and replaceable shells. Replaceable shells tell me that the guts are worth reusing even if the remote is fucked.
I’m sure it will do me just fine!
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That’s some big kids watts. Might be discussed above, I’ve had great results with tattu packs. I’m planning to put all 4, 6s packs in my board, 12s2p, 28ah. 25c lipos.
This brick is almost the same dimensions as a 12s7p Of 40t I made for @Saturn_Corp. Also a 28ah pack, but amp rating 150s~200.
I know there are other reasons to pick one chemistry over the other, but if you want to literally melt concrete, lipos seem like the ticket.
Nvm, I found you a turn key solution.
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Haha yea I just need a tesla module and i’m good.
I thought about Lipos but I really don’t mind the weight on this board. It actually helps a bit to be heavy, We plan to use this board for some light wake boarding this summer. My current 4wd board just can’t stay on the floor in a straight line without some scary pulling/tail whip from the ass end.
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I love this lol… It’s all about that POWER
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In terms of volume, a 80100 is almost exactly 4 times the volume of a 5065…this board has 16 times the motor volume as my light board…that’s insane
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I know exactly what a single 80100 is capable of. It will happily take 130A and more at peak, the resulting thrust is hard to stand at 15% throttle expo, and that is only a single motor…
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Had 2x vesc6+ on 14s for ~100km on full Trampa build. Battery was never fully charged, only to 56V. I know it was stupid and risky, but there weren’t any problems.
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I’m running 13s6p on escapes.
It works but a bit premature to say for sure. Only tested on one ride so far.
I am using current control and on the bench going full forward full reverse it would fault abs over current with 220 amp spikes.
To overcome this I went with the no hardware limits fw and set absolute max current to 250. No faults occurred afterwards.
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